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A computational fluid dynamics coupled population balance model (CFD-PBM) was used to numerically simulate the fluid dynamics of bubble swarms in a bubble column containing non-Newtonian fluids. The effects of superficial gas velocity (Ug), the consistency index (K), and the flow index (n) on bubble size distribution (BSD), gas holdup, and fluid dynamic viscosity in a bubble column were analyzed at both local and overall scales. As Ug increases, the bubble breakup occurs excessively, the gas holdup increases, and the dynamic viscosity decreases. K and n were used to characterize the rheological properties of power law fluid. As K increases, fluid viscosity increases, bubble breakup rate decreases, gas holdup in the top zone is slightly lower than in the middle zone, and dynamic viscosity increases. Within the range of n from 0.45 to 1.07, when n is smallest, the relative frequency of bubbles smaller than the initial size is relatively large, and the overall and local gas holdup are the highest. When n = 1.07, the fluid exhibits shear-thickening properties, and the dynamic viscosity variations are significant. [ABSTRACT FROM AUTHOR]

Background: To identify reliable magnetic resonance imaging (MRI) features that can differentiate confluent fibrosis (CF) from infiltrative hepatocellular carcinoma (HCC). Methods: A retrospective analysis was conducted on Twenty CF patients and 28 infiltrative HCC patients who underwent upper abdomen MRI scans. The imaging features of lesions were analyzed, and the apparent diffusion coefficient (ADC) of lesions were measured. Accuracy, sensitivity and specificity for the diagnosis of CF were calculated for each category individually and combined. Results: Compared to infiltrative HCC, hepatic capsular retraction at the site of lesion, hepatic volume loss at the site of lesion and "nodular surround sign" were more common in patients with CF (all P < 0.001). Hepatic volume loss at the site of lesion, no or mild enhancement in arterial phase, and hyper-enhancing in delayed phase to the background parenchyma showed superior diagnostic accuracy (83.3%, 85.4%, 97.9%, respectively). When the lesion exhibited hepatic volume loss at the site of lesion or no or mild enhancement in arterial phase or hyper-enhancing in delayed phase, a sensitivity of 100.0% for the diagnosis of CF was achieved. When the lesion was positive for any two of three categories, or positive for all three categories, a specificity of 100.0% was achieved. The ADC values of CF were higher than those of infiltrative HCC (P < 0.001). Conclusion: The combination of the hepatic volume loss at the site of lesion, no or mild enhancement in arterial phase, and hyper-enhancing in delayed phase to the background parenchyma can be considered reliable MR features for the diagnosis of CF, as they allow differentiation from infiltrative HCC. [ABSTRACT FROM AUTHOR]

The Palaeo-Mesozoic geodynamic evolution of the Tangjia–Sumdo accretionary complex belt, which separates the North and South Lhasa Terrane, remains controversial. Moreover, the lack of geological records restricts the understanding of the evolution of the Sumdo Palaeo-Tethys Ocean from the middle Permian until the middle Triassic. Here we present zircon U–Pb geochronology, whole-rock geochemistry and Sr–Nd–Hf isotopic compositions of the Yeqing gabbro. Zircon U–Pb geochronology yields ages from 254 ± 1 to 249 ± 1 Ma. In situ Hf isotopic analyses yield ϵ Hf(t) values of −0.2 to +6.3. These samples have high TiO2 (3.69 wt %) and P2O5 (0.78 wt %) contents, with typical patterns like ocean island basalt (OIB). Besides, they are classified as high-Nb basalts (HNBs) based on the high content of Nb (45.3–113.5 ppm). Whole-rock Sr–Nd isotopic compositions are similar to OIB, with initial 87Sr/86Sr of 0.7047–0.7054, 143Nd/144Nd of 0.512526–0.512647 and ϵ Nd(t) of 0.3–2.7. These signatures suggest that the Yeqing gabbro is mainly derived from low-degree melting of the garnet lherzolite mantle. Based on field observations of HNBs intruding into the continental margin and their geochemical characteristics, we infer that the Yeqing gabbro was generated in a subduction environment. Combined with the regional geology of the subduction environment and the evolution of oceanic islands in the Sumdo Palaeo-Tethys Ocean, we propose that the Yeqing gabbro may represent a product of the asthenosphere upwelling through a slab window produced by subduction of seismic ridge in the Sumdo Palaeo-Tethys Ocean, called plume – subduction-zone interaction, during the late Permian to early Triassic. [ABSTRACT FROM AUTHOR]

We report herein a rare example of enantiodivergent aldehyde addition with β‐alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6‐Di‐9‐anthracenyl‐substituted chiral phosphoric acid‐catalyzed asymmetric allylation using β‐vinyl substituted allylic boronate gave alcohols with R absolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with β‐2‐propenyl substituted allylic boronate generated homoallylic alcohol products with S absolute configuration. Unusual substrate‐catalyst C−H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies. [ABSTRACT FROM AUTHOR]

We report herein a rare example of enantiodivergent aldehyde addition with β‐alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6‐Di‐9‐anthracenyl‐substituted chiral phosphoric acid‐catalyzed asymmetric allylation using β‐vinyl substituted allylic boronate gave alcohols with R absolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with β‐2‐propenyl substituted allylic boronate generated homoallylic alcohol products with S absolute configuration. Unusual substrate‐catalyst C−H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies. [ABSTRACT FROM AUTHOR]

Owing to the impact of the Paleo-, Meso-, and Neo-Tethys Oceans, the Triassic evolution of the Lhasa Terrane is complex and remains debated. The little-known subduction of the oceanic lithosphere of the Sumdo Paleo-Tethys Ocean (SPTO) in the Triassic has especially constrained our understanding of the evolution of the Lhasa Terrane. We investigated the newly identified Triassic granite and metabasalt in the Sumdo area to detail new constraints regarding the Triassic subduction of the SPTO oceanic lithosphere and evolution of the Lhasa Terrane. Zircon LA-ICP-MS U Pb dating for granite and metabasalt yielded crystallization ages of 238.4–236.1 Ma. The granites were strongly peraluminous I-type granites with weakly fractional crystallization. High Nb contents (on average 51.91 ppm), low ε Hf (t) values (−19.7 to +2.8), and ε Nd (t) values (−2.86 to −2.2) suggest that the granites were likely generated by mixing of mantle melts and their induced melts of ancient crustal materials. Metabasalts were analogous to island arc tholeiite with negative Th, Nb, Ti, Zr, and Hf anomalies and positive ε Nd (t) values (+6.1 to +7.1), demonstrating that the magma was likely derived from the partial melting of the depleted mantle metasomatized by subduction fluids. Combined with Triassic magmatism in the Lhasa Terrane, we consider that a divergent double subduction of the SPTO oceanic lithosphere produced the Early Triassic to early Late Triassic magmatism (248–221 Ma) concentrating on both sides of the SPTO suture zone. The Middle Triassic granites and metabasalts in this study were formed in the continental and intra-oceanic arcs, respectively, of the SPTO. Subsequently, closure of the SPTO and collision between the central- and southern Lhasa Terrane might have triggered the subduction of the Indus–Yarlung Tsangbo oceanic lithosphere broadly generating the late Late Triassic magmatism (217–201 Ma) in the Lhasa Terrane. • Middle Triassic I-type granite and tholeiite occurred in the Central Lhasa Terrane. • Mixing of the mantle- and ancient crustal melts produced the I-type granite. • Partial melting of the depleted mantle metasomatized by fluids formed the tholeiite. • They were resulted in the subduction of the Sumdo Paleo-Tethys Oceanic lithosphere. [ABSTRACT FROM AUTHOR]

Summary: Sphingosine‐1‐phosphate (S1P) is a bioactive sphingolipid metabolite. The past decade has witnessed exponential growth in the field of S1P research, partly attributed to drugs targeting its receptors or kinases. Accumulating evidence indicates that changes in the S1P axis (i.e., S1P production, transport, and receptors) may modify metabolism and eventually mediate metabolic diseases. Dysfunction of the mitochondria on a master monitor of cellular metabolism is considered the leading cause of metabolic diseases, with aberrations typically induced by abnormal biogenesis, respiratory chain complex disorders, reactive oxygen species overproduction, calcium deposition, and mitophagy impairment. Accordingly, we discuss decades of investigation into changes in the S1P axis and how it controls mitochondrial function. Furthermore, we summarize recent scientific advances in disorders associated with the S1P axis and their involvement in the pathogenesis of metabolic diseases in humans, including type 2 diabetes mellitus and cardiovascular disease, from the perspective of mitochondrial function. Finally, we review potential challenges and prospects for S1P axis application to the regulation of mitochondrial function and metabolic diseases; these data may provide theoretical guidance for the treatment of metabolic diseases. [ABSTRACT FROM AUTHOR]

Apolipoprotein A-I binding protein (AIBP), a secreted protein, has been shown to play a pivotal role in the development of atherosclerosis. The function of intracellular AIBP, however, is not yet well characterized. Here, we found that AIBP is abundantly expressed within human and mouse atherosclerotic lesions and exhibits a distinct localization in the inner membrane of mitochondria in macrophages. Bone marrow-specific AIBP deficiency promotes the progression of atherosclerosis and increases macrophage infiltration and inflammation in low-density lipoprotein receptor-deficient (LDLR−/−) mice. Specifically, the lack of mitochondrial AIBP leads to mitochondrial metabolic disorders, thereby reducing the formation of mitophagy by promoting the cleavage of PTEN-induced putative kinase 1 (PINK1). With the reduction in mitochondrial autophagy, macrophages polarize to the M1 proinflammatory phenotype, which further promotes the development of atherosclerosis. Based on these results, mitochondrial AIBP in macrophages performs an antiatherosclerotic role by regulating of PINK1-dependent mitophagy and M1/M2 polarization. 9wPYiwBcJkigAW4BX-B6DE Video Abstract [ABSTRACT FROM AUTHOR]

Computations and experiments leading to new chiral phosphoric acids (CPAs) for epoxide thionations are reported. Density functional theory calculations reveal the mechanism and origin of the enantioselectivity of such CPA‐catalyzed epoxide thionations. The calculated mechanistic information was used to design new efficient CPAs that were tested experimentally and found to be highly effective. Bulky ortho‐substituents on the 3,3′‐aryl groups of the CPA are important to restrict the position of the epoxide in the key transition states for the enantioselectivity‐determining step. Larger para‐substituents significantly improve the enantioselectivity of the reaction. [ABSTRACT FROM AUTHOR]

Computations and experiments leading to new chiral phosphoric acids (CPAs) for epoxide thionations are reported. Density functional theory calculations reveal the mechanism and origin of the enantioselectivity of such CPA‐catalyzed epoxide thionations. The calculated mechanistic information was used to design new efficient CPAs that were tested experimentally and found to be highly effective. Bulky ortho‐substituents on the 3,3′‐aryl groups of the CPA are important to restrict the position of the epoxide in the key transition states for the enantioselectivity‐determining step. Larger para‐substituents significantly improve the enantioselectivity of the reaction. [ABSTRACT FROM AUTHOR]

Calculating the temperatures of magmas from which granitoid rocks solidify is a key task of studying their petrogenesis, but few geothermometers are satisfactory. Zircon saturation thermometry has been the most widely used because it is conceptually simple and practically convenient, and because it is based on experimental calibrations with significant correlation of the calculated zircon saturation temperature (TZr) with zirconium (Zr) content in the granitic melt (i.e., TZr ∝ ZrMELT). However, application of this thermometry to natural rocks can be misleading, resulting in the calculated TZr having no geological significance. This thermometry requires Zr content and a compound bulk compositional parameter M of the melt as input variables. As the Zr and M information of the melt is not available, petrologists simply use bulk-rock Zr content (ZrBULK-ROCK) and M to calculate TZr. In the experimental calibration, TZr shows no correlation with M, thus the calculated TZr is only a function of ZrMELT. Because granitoid rocks represent cumulates or mixtures of melt with crystals before magma solidification and because significant amount Zr in the bulk-rock sample reside in zircon crystals of varying origin (liquidus, captured or inherited crystals) with unknown modal abundance, ZrBULK-ROCK cannot be equated with ZrMELT that is unknown. Hence, the calculated magma temperatures TZr using ZrBULK-ROCK have no significance in both theory and practice. As an alternative, we propose to use the empirical equation T S i O 2 (°C) = -14.16 × SiO2 + 1723 for granitoid studies, not to rely on exact values for individual samples but focus on the similarities and differences between samples and sample suites for comparison. This simple and robust thermometry is based on experimentally determined phase equilibria with T ∝ 1/SiO2. [ABSTRACT FROM AUTHOR]

To establish the dynamic model of machine tool structure is an important means to assess the performance of the machine tool structure during the cutting process. It is necessary to study the dynamics of the machine tools in different configurations for the sake of analyzing the dynamic behavior of the machine tools in the entire workspace. In this paper, a robust approach is presented to build an efficient and reliable dynamic model to evaluate the position-dependent dynamics of the twin ball screw (TBS) feed system. First, the TBS feed system is divided into several components, and a finite element (FE) model is built for each component. Second, the Craig-Bampton method is proposed to reduce the order of the substructures. Third, a multipoint constraints (MPCs) method was introduced to model the mechanical joint substructures of the TBS system, and the spring-damper element (SDE) is employed to connect the condensation nodes. Finally, a series experimental tests and full-order FE analysis are conducted on the self-designed TBS worktable in the four positions to validate the effectiveness of the proposed dynamic model. The results show that the proposed approach evaluates accurately the position-dependent behavior of the TBS system. [ABSTRACT FROM AUTHOR]

Obesity is a global public health issue. Obesity-related chronic low-grade inflammation (meta-inflammation) can lead to aberrant adipokine release and promote cardiometabolic diseases and obesity-related tumors. However, the mechanisms involved in the initiation of inflammatory responses in obesity and obesity-related tumors as well as metastasis are not fully understood. In this study, we found that the increased tumor necrosis factor-alpha (TNF-α) in adipocytes promoted the lung metastasis of MC38 colon cancer cells via Fas signaling. The release of TNF-α and interleukin (IL)-6 by Fas signaling in adipocytes was caused by the activation of the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways mediated by the interaction of Fas with Bmx, a non-receptor tyrosine kinase. Moreover, the Fas/Bmx complex is involved in the inflammation of adipocytes via Fas at the Tyr189 site and SH2 domain of Bmx. This is the first study to report the interaction between Fas and Bmx in adipocyte inflammation, which may provide clues for the development of potential new treatment strategies for obesity-related diseases. [ABSTRACT FROM AUTHOR]

We report herein the development of stereodivergent syntheses of enantioenriched homoallylic alcohols using chiral nonracemic α‐CH2Bpin‐substituted crotylboronate. Chiral phosphoric acid (S)‐A‐catalyzed asymmetric allyl addition with the reagent gave Z‐anti‐homoallylic alcohols with excellent enantioselectivities and Z‐selectivities. When the enantiomeric acid catalyst (R)‐A was utilized, the stereoselectivity was completely reversed and E‐anti‐homoallylic alcohols were obtained with high E‐selectivities and excellent enantioselectivities. By pairing the chirality of the boron reagent with the catalyst, two complementary stereoisomers of chiral homoallylic alcohols can be obtained selectively from the same boron reagent. DFT computational studies were conducted to probe the origins of the observed stereoselectivity. These reactions generate highly enantioenriched homoallylic alcohol products that are valuable for rapid construction of polyketide structural frameworks. [ABSTRACT FROM AUTHOR]

We report herein the development of stereodivergent syntheses of enantioenriched homoallylic alcohols using chiral nonracemic α‐CH2Bpin‐substituted crotylboronate. Chiral phosphoric acid (S)‐A‐catalyzed asymmetric allyl addition with the reagent gave Z‐anti‐homoallylic alcohols with excellent enantioselectivities and Z‐selectivities. When the enantiomeric acid catalyst (R)‐A was utilized, the stereoselectivity was completely reversed and E‐anti‐homoallylic alcohols were obtained with high E‐selectivities and excellent enantioselectivities. By pairing the chirality of the boron reagent with the catalyst, two complementary stereoisomers of chiral homoallylic alcohols can be obtained selectively from the same boron reagent. DFT computational studies were conducted to probe the origins of the observed stereoselectivity. These reactions generate highly enantioenriched homoallylic alcohol products that are valuable for rapid construction of polyketide structural frameworks. [ABSTRACT FROM AUTHOR]

• The development of omics technology provides a powerful tool for studying VC. • Multi-omics analysis provides a more comprehensive understanding of the pathophysiological mechanism of VC. • Omics technology promotes the clinical diagnosis of VC. Vascular calcification (VC), the pathological process of hydroxyapatite mineral deposition in the vascular system, is closely associated with aging, atherosclerotic plaque formation, cardiovascular disease (CVD) and diabetes mellitus (DM). Studies have shown that VC is related to cellular phenotypic changes, extracellular vesicles, disordered calcium and phosphate homeostasis, and an imbalance between inducers and inhibitors of VC. Unfortunately, there is currently no effective preventive or targeted treatment for pathologic condition. The rapid evolution of omics technology (genomics, epigenomics, transcriptomics, proteomics and metabolomics) has provided a novel approach for elucidation of pathophysiologic mechanisms in general and those associated with VC specifically. Here, we review articles published over the last twenty years and focus on the current state, challenges, limitations and future of omics in VC research and clinical practice. Highlighting potential targets based on omics technology will improve our understanding of this pathologic condition and assist in the development of potential treatment options for VC related disease. [ABSTRACT FROM AUTHOR]

• The development of omics technology provides a powerful tool for studying VC. • Multi-omics analysis provides a more comprehensive understanding of the pathophysiological mechanism of VC. • Omics technology promotes the clinical diagnosis of VC. Vascular calcification (VC), the pathological process of hydroxyapatite mineral deposition in the vascular system, is closely associated with aging, atherosclerotic plaque formation, cardiovascular disease (CVD) and diabetes mellitus (DM). Studies have shown that VC is related to cellular phenotypic changes, extracellular vesicles, disordered calcium phosphate homeostasis and an imbalance between inducers and inhibitors of VC. Unfortunately, there is currently no effective preventive or targeted treatment for this disorder. Recently, the evolution of omics technology (genomics, epigenomics, transcriptomics, proteomics and metabolomics) has paved the way for elucidation of complex biochemical processes and, as such, may provide new insight on VC. Accordingly, we conducted a review of articles published over the last twenty years and herein focus on current and future potential of omics technology in clarifying mechanisms of this disease process. Identification of new biomarkers will provide additional tools in characterizing this pathology and will further assist in the development of potential therapeutic targets. [ABSTRACT FROM AUTHOR]

The time kinetics of hot carrier degradation (HCD) is modeled using a reaction diffusion drift (RDD) framework. It is incorporated into Sentaurus Device TCAD and validated using conduction mode HCD data in n- and p-channel MOSFETs and FinFETs. RDD-enabled TCAD calculates carrier-energy-initiated generation of interface traps (Δ NIT) and the impact of the resulting localized charges on device parametric drift. HCD at various gate (VG) and drain (VD) biases spanning various modes (VG ≤ and > VD) are simulated for low stress VD (< 3 V). The self-heating (SH)-effect-induced temperature (T) increase is invoked for FinFETs. Data from various experiments are analyzed and a wide range of power-law time kinetics slope (n) is explained. [ABSTRACT FROM AUTHOR]

In order to accurately analyze the safety management efficiency of China's coal enterprises, based on the panel data of 14 coal listed enterprises in 2012–2018, this paper analyzes the overall technical efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) of safety management of sample enterprises by the Data Envelopment Analysis (DEA) model, and builds Tobit model of random panel effect to evaluate the impact of business management and safety investment on safety management efficiency. The results show that: in 2012–2018, the average values of TE, PTE and SE of sample enterprises are respectively 0.674, 0.777 and 0.864; all have great room for improvement. The development of PTE and SE in most sample enterprises is unbalanced; TE of sample enterprises does not significantly improve, and shows a trend of rising-decreasing-rising; safety investment, enterprise scale and labor productivity are significantly positively related to safety management technical efficiency, while safety training person time and employees quality are negatively correlated. This paper identified the positive and negative effects of various influencing factors on the safety management efficiency of coal enterprises, and analyzed the main reasons that hinder the improvement of safety efficiency, and puts forward corresponding countermeasures and suggestions, which are helpful for coal enterprises to effectively improve their safety management efficiency and economic efficiency. [ABSTRACT FROM AUTHOR]

In this paper, the attitude tracking control problem of output feedback is investigated. A finite time extended state observer (FTESO) is designed through the homogeneous Lyapunov method to estimate the virtual angular velocity and total disturbances. Based on these estimated states, a finite time attitude tracking controller is developed. The numerical simulations are given to illustrate the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

We report a dual function asymmetric catalysis by a chiral phosphoric acid catalyst that controls both enantioselective addition of an achiral α‐vinyl allylboronate to aldehydes and pseudo‐axial orientation of the α‐vinyl group in the transition state. The reaction produces dienyl homoallylic alcohols with high Z‐selectivities and enantioselectivities. Computational studies revealed that minimization of steric interactions between the alkyl groups of the diol on boron and the chiral phosphoric acid catalyst influence the orientation of α‐vinyl substituent of the allylboronate reagent to occupy a pseudo‐axial position in the transition state. [ABSTRACT FROM AUTHOR]

We report a dual function asymmetric catalysis by a chiral phosphoric acid catalyst that controls both enantioselective addition of an achiral α‐vinyl allylboronate to aldehydes and pseudo‐axial orientation of the α‐vinyl group in the transition state. The reaction produces dienyl homoallylic alcohols with high Z‐selectivities and enantioselectivities. Computational studies revealed that minimization of steric interactions between the alkyl groups of the diol on boron and the chiral phosphoric acid catalyst influence the orientation of α‐vinyl substituent of the allylboronate reagent to occupy a pseudo‐axial position in the transition state. [ABSTRACT FROM AUTHOR]

Herein we report the controllable synthesis of NaYF4:Yb3+/Er3+via mesoscale regulation through the introduction of Li+/K+ into a hydrothermal system. The crystal evolution process of β-NaYF4:Yb3+/Er3+ is investigated based on the reaction parameters. The mesoscale growth process includes four stages: (1) nucleation, (2) aggregation, (3) orientation growth, and (4) ripening. Through the introduction of Li+/K+ into the hydrothermal environment, super-small β-NaYF4:Yb3+/Er3+ upconversion nanoparticles can be obtained. [ABSTRACT FROM AUTHOR]

The nonsynchronous error of the dual-driven feed system seriously affects the positioning and machining accuracy of CNC machine tools. Improving the positioning error is an extremely important task as it determines the geometric accuracy of the manufactured parts. In this paper, a Multivariate Orthogonal Polynomial Regression model has been developed to predict the positioning error in terms of motion parameters such as position and speed of the X1 and X2 axes of the dual-driven worktable. Orthogonal Experimental Design has been engaged in conducting experiments. The positioning errors are measured by a dual-frequency laser interferometer. In addition, a real-time error compensation system is developed based on the proposed active compensation control strategy in the dual-driven feed system controlled by Beckhoff motion control card. Experimental results show that the proposed positioning error model and error compensation strategy can be utilized as an effective manner to improve the accuracy of dual-driven CNC machine tools. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Early Carboniferous clastic sediments in the North Lhasa Terrane was mainly from the Indian continent and partly from the Australian continent. • The North Lhasa Terrane may be located at the northern margin of the Indian- and Australian continent during the Early Carboniferous. • The reduction of Grenvillian detrital zircons in the Yongzhu Formation might be associated with the Early Carboniferous rifting process in the eastern Lhasa Block. The Lhasa Block was located at the northern margin of East Gondwana before it drifted away, but its exact paleogeographic location in the Late Paleozoic remains controversial. The Late Paleozoic strata in the Lhasa Block, especially the Lower Carboniferous, for which the rock assemblage and sedimentary age have been described but the in-depth research on provenance and tectonic environment are still lacking, may provide vital information about its paleogeographic location. This study presents a systematic field geological survey of the Lower Carboniferous Yongzhu Formation, along with U-Pb dating and Hf isotope analysis of detrital zircons. The detrital zircons U-Pb data revealed major age peaks at 530 and 980 Ma as well as several subordinate age peaks at 784, 890, 1160, 1514, 1690, 2480, and 2600 Ma. The Hf isotopes of the detrital zircons showed similarity with zircons from the Indian continent on the age peaks at 980 and 890 Ma and with those from the Australian continent on the age peaks at 1160 and 2600 Ma, which indicates mixed provenance for the Yongzhu Formation. From this study, we infer that the Lhasa Block might have been located at the northern margin of the Indian and Australian continents during the Early Carboniferous. The weaker age peak at 1160 Ma of the Lower Carboniferous compared to the Pre-Carboniferous and Upper Carboniferous-Lower Permian might be related to the opening of the Sumdo Paleo-Tethys Ocean. [ABSTRACT FROM AUTHOR]

This paper considers application of the fault tree method to analyze types and reasons for failure of an annular blowout preventer (BOP). In combination with fuzzy relation analysis theory, we have calculated the fuzzy importance of basic events which can lead to failure plus the correlation coefficient for the minimum cut sets. Consequently, we can obtain the degree of correlation between the top event and the minimum cut sets. We have determined the key factors influencing stable operation of the annular BOP. Our results can provide a theoretical basis for use and improvement of an annular BOP. [ABSTRACT FROM AUTHOR]

In present work, the deformation behavior of AZ31 Mg alloy with surface mechanical attrition treatment (SMAT) had been studied. The microstructure and mechanical properties of AZ31 Mg alloy with SMAT were investigated. The results indicated that a gradient nanostructure could be formed in sample by SMAT, in which the grain size increased gradually from surface to matrix. A depth-dependent gradient microhardness was also formed due to the corresponding gradient microstructure. Yield strength and ultimate tensile strength of AZ31 Mg alloy with SMAT were significantly improved combining with decrease of fracture elongation. The effect of SMAT on anisotropy of mechanical properties of AZ31 alloy had been discussed and analyzed. The plastic anisotropy of the sample increased significantly after SMAT, which was related to the texture variation of rolled sheet and special deformation behavior of gradient nanostructure. Finally, in order to illuminate the difference in deformation behavior between fine and coarse grained microstructure, the in-situ tensile deformation behavior of AZ31 Mg alloy with one-side gradient structure had been studied by SEM. The deformation mechanism of AZ31 Mg alloy with gradient structure had been put forward. [ABSTRACT FROM AUTHOR]

• A fully physical TCAD framework to model the NBTI is validated with differently processes MOSFET measured data. • RD model with ABDWT model for interface trap generation, RDD model for bulk trap generation, ABDWT model for hole trapping is used. • Framework Validation in TCAD in 3D FinFETs and GAA-FETs is in progress. A physics-based framework is incorporated in TCAD to model the primary mechanisms responsible for Negative Bias Temperature Instability (NBTI) in P channel High-K Metal Gate (HKMG) MOSFETs. Three underlying mechanisms are treated including interface trap generation-passivation via a Reaction-Diffusion (RD) model and its charge occupancy via an Activated Barrier Double Well Thermionic (ABDWT) model, hole trapping and de-trapping in pre-existing defects in the gate stack are modeled via an ABDWT model, and bulk trap generation-passivation is modeled via a Reaction-Diffusion-Drift (RDD) model. The framework is used to model measured NBTI time-kinetics for DC stress-recovery and various mixed DC-AC gate pulse segments for planar devices. Furthermore, the same framework is also used to test NBTI behavior in 3D FinFETs. [ABSTRACT FROM AUTHOR]

Late Permian to early Triassic gabbro in North Lhasa, Tibet: evidence for plume - subduction-zone interaction of the Palaeo-Tethys ocean - RETRACTION The following article has been retracted at the request of the authors: Duan M-L, Xie C-M, Wang B, Song Y-H, Li W-q, and Hao Y-j. Late Permian to early Triassic gabbro in North Lhasa, Tibet: evidence for plume - subduction-zone interaction of the Palaeo-Tethys ocean. The first and corresponding authors initiated this retraction with the permission of all authors. [Extracted from the article]

Silicon bandgap limits the reduction of operation voltage when downscaling device sizes. This increases the electrical field within-a-device and hot carrier aging (HCA) is becoming an important reliability issue again for some CMOS technologies. For nanodevices, there are a number of challenges for characterizing their HCA: the random charge–discharge of traps in gate dielectric causes “within-a-device-fluctuation (WDF),” making the parameter shift uncertain after a given HCA. This can introduce errors when extracting HCA time exponents and it will be shown that the lower envelope of the WDF must be used. Nanodevices also have substantial device-to-device variation (DDV) and multiple tests are needed for evaluating their standard deviation ( $\sigma )$ and mean value ( $\mu $ ). Repeating the time-consuming HCA tests is costly and a voltage-step-stress method is applied to reduce the number of tests by 80%. For a given number of devices under tests (DUTs), there is a little information on the accuracy of the extracted $\sigma $ and $\mu $ . We will develop a method to provide this information, based on the defect-centric model. For 40 DUTs with an average of ten traps per device, the extracted $\mu $ and $\sigma $ has an accuracy of ±14% and ±24%, respectively, with a 95% confidence. [ABSTRACT FROM PUBLISHER]

We have successfully developed a series of novel and modular ferrorence-based amino-phosphine-alcohol (f-Amphol) ligands, and applied them to iridium-catalyzed asymmetric hydrogenation of various simple ketones to afford the corresponding chiral alcohols with excellent enantioselectivities and conversions (98-99.9 % ee, >99 % conversion, turnover number up to 200 000). Control experiments and density functional theory (DFT) calculations have shown that the hydroxyl group of our f-Amphol ligands played a key role in this asymmetric hydrogenation. [ABSTRACT FROM AUTHOR]

The access transistor of SRAM can suffer both positive bias temperature instability (PBTI) and hot carrier aging (HCA) during operation. The understanding of electron traps (ETs) is still incomplete and there is little information on their similarity and differences under these two stress modes. The key objective of this paper is to investigate ETs in terms of energy distribution, charging and discharging properties, and generation. We found that both PBTI and HCA can charge ETs which center at 1.4 eV below conduction band ( Ec ) of high-k dielectric, agreeing with theoretical calculation. For the first time, clear evidences are presented that HCA generates new ETs, which do not exist when stressed by PBTI. When charged, the generated ETs’ peak is 0.2 eV deeper than that of preexisting ETs. In contrast with the power law kinetics for charging the preexisting ETs, filling the generated ETs saturates in seconds, even under an operation bias of 0.9 V. ET generation shortens device lifetime and must be included in modeling HCA. A cyclic and antineutralization ETs model is proposed to explain PBTI and HCA degradation, which consists of preexisting cyclic ETs, generated cyclic ETs, and antineutralization ETs. [ABSTRACT FROM AUTHOR]

The Qinling Orogen was a consequence of continental collision of the South China Craton with the North China Craton in the Triassic and caused widespread granitoid magmatism. However, the petrogenesis of these granitoids remains controversial. In this paper, we choose the Baijiazhuang (BJZ) and Lvjing (LJ) plutons in the West Qinling Orogen for a combined study of the zircon U–Pb geochronology, whole-rock major and trace element compositions and Sr–Nd–Hf isotopic characteristics. We obtained zircon crystallization ages of ~ 216 Ma and ~ 212 Ma for the BJZ and the LJ plutons, respectively. The granitoid samples from both plutons have high K 2 O metaluminous to peraluminous compositions. They are enriched in large ion lithophile elements (LILEs), light rare earth elements (LREEs) and depleted in high field-strength elements (HFSEs) with significant negative Eu anomalies. The BJZ samples have initial Sr isotopic ratios of 0.7032 to 0.7078, ε Nd ( t ) of − 10.99 to − 8.54 and ε Hf ( t ) of − 10.22 to − 6.41. The LJ granitoids have initial Sr isotopic ratios of 0.7070 to 0.7080, ε Nd ( t ) of − 5.37 to − 4.58 and ε Hf ( t ) of − 3.64 to − 1.78. The enriched isotopic characteristics of the two plutons are consistent with their source being dominated by ancient continental crust. However, two BJZ samples show depleted Sr isotope compositions, which may infer possible involvement of mantle materials. Mantle-derived melt, which formed from partial melting of mantle wedge peridotite facilitated by dehydration of the subducted/subducting Mianlue ocean crust, provide the required heat for the crustal melting while also contributing to the compositions of these granitoids. That is, the two granitic plutons are magmatic responses to the closure of the Mianlue ocean basin and the continental collision between the Yangtze and South Qinling crustal terranes. [ABSTRACT FROM AUTHOR]

Sensor-based human activity recognition is an emerging research field. It is an important application of Internet of Things (IoT). and has very promising application prospects in health care/recovery, elder/invalid people assistant, smart home/office, etc. Accuracy is one of the most important evalution standards of activity recognition, and appropriate features and classifiers are important accuracy factors. We first extract a novel feature called correlation feature. By combining the theory of compressive sensing and sparse representation, we propose a multi-task compressive sensing method and use it as the classifier to resolve the problem of activity recognition. Finally, we conduct a large amount of experiments on a set of benchmarks with Leave-One-Subject-Out cross validation. Experimental results show that the extracted feature and the proposed method are effective in improving the accuracy of sensor-based activity recognition. Moreover, compared to the corresponding single task method, the proposed classifier can reduce the execution time by nearly 56%. [ABSTRACT FROM AUTHOR]

Objective To investigate the incidence and risk factors of human papillomavirus type 16 (HPV16) infection among women through health screenings in Tianjin urban area. Methods A total of 2 000 women from Tianjin urban area were recruited for this study, and potential risk factors were investigated by questionnaire as well as by collecting cervical exfoliated cells from the participants. HPV type was examined using polymerase chain reaction and pyrosequencing technology, then the risk factors of HPV16 infection were examined by chi square test and the multiple factor logistic regression analysis. Results Among those 2 000 women who received health screenings, a total of 271 cases were HPV positive (13.55%). HPV16 accounts for the most common human papillomavirus types (39.5%, 107/271) while HPV58 account for 15.13% (41/271)and HPV18 account for 9.59% (26/271). Factors related to HPV16 infection were investigated include smoking history, initial age of sex (>25 years old or not), number of pregnancies (≥2 or not), number of sexual partners (≥2 or not) and contraception measures (condom or other ways) with χ²=6.268, 8.540, 4.951, 7.123, 6.053, 5.019, respectively. (P < 0.05). Age, alcohol intake, education level and previous gynecologial examination did not differ significantly among HPV16 positive patients compared to those with negative HPV. Multiple factor Logistic regression model analysis showed that the independent factors were smoking history and initial age for sex (≤25 years old)(P < 0.05). Conclusion HPV16 is the most common type of cervical infection among women in Tianjin urban area. Changing inappropriate sexual behavior and smoking cessation are effective measures to prevent HPV16 infection and reduce incidence of cervical cancer. [ABSTRACT FROM AUTHOR]

SRAM is vulnerable to device-to-device variation (DDV), since it uses minimum-sized devices and requires device matching. In addition to the as-fabricated DDV at time-zero, aging induces a time-dependent DDV (TDDV). Bias temperature instability (BTI) is a dominant aging process. A number of techniques have been developed to characterize the BTI, including the conventional pulse- \(I\) – \(V\) , random telegraph noises, time-dependent defect spectroscopy, and TDDV accounting for the within-device fluctuation. These techniques, however, cannot be directly applied to SRAM, because their test conditions do not comply with typical SRAM operation. The central objective of this paper is to develop a technique suitable for characterizing both the negative BTI (NBTI) and positive BTI (PBTI) in SRAM. The key issues addressed include the SRAM relevant sensing Vg, measurement delay, capturing the upper envelope of degradation, sampling rate, and measurement time window. The differences between NBTI and PBTI are highlighted. The impact of NBTI and PBTI on the cell-level performance is assessed by simulation, based on experimental results obtained from individual devices. The simulation results show that, for a given static noise margin, test conditions have a significant effect on the minimum operation bias. [ABSTRACT FROM PUBLISHER]

As a kind of improved SCR, the steel lazy-wave riser (SLWE) gained more and more application in the development of deepwater oil and gas field. The configuration of the SLWE is of great significance in its design process. Under ocean current, the configuration and mechanical parameters of the SLWE vary a lot. A model of multipoint boundary-value differential equations based on the nonlinear large deformation beam theory was proposed to simulate the responses of the SLWE under ocean current. Numerical program was built to get the approximate solution to the theoretical model and parametric analysis was conducted to study the influences of different ocean currents on the configuration of the SLWE. Eesults show that the axial tension force at the touchdown point of the SLWE increases distinctly with the rise of the ocean current velocity, which deserves full consideration in the configuration design of the SLWE. The proposed model makes an important reference for the performance analysis of the deepwater SLWE. [ABSTRACT FROM AUTHOR]

Background: Metastasis accounts for the most deaths in patients with hepatocellular carcinoma (HCC). Receptor activator of nuclear factor kappa B ligand (RANKL) is associated with cancer metastasis, while its role in HCC remains largely unknown. Methods: Immunohistochemistry was performed to determine the expression of RANK in HCC tissue (n = 398). Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to examine the expression of RANK, E-cadherin, N-cadherin, vimentin, Snail, Slug, Twist and MMPs in HCC cells. Wound healing and Transwell assays were used to evaluate cell migration and invasion ability. Results: We found that expression of RANK, the receptor of RANKL, was significantly higher in HCC tumor tissues than in peritumor liver tissues (p<0.001). Constitutive expression of RANK was detected in HCC cell lines, which can be up-regulated when HCC cells were stimulated with RANKL. Notably, in vitro experiments showed that activation of RANKL-RANK axis significantly promoted migration and invasion ability of HCC cells. In addition, RANKL stimulation increased the expression levels of N-cadherin, Snail, and Twist, while decreased the expression of E-cadherin, with concomitant activation of NF-κB signaling pathway. Moreover, administration of the NF-κB inhibitor attenuated RANKL-induced migration, invasion and epithelial-mesenchymal transition of HCC cells. Conclusions: RANKL could potentiate migration and invasion ability of RANK-positive HCC cells through NF-κB pathway-mediated epithelial-mesenchymal transition, which means that RANKL-RANK axis could be a potential target for HCC therapy. [ABSTRACT FROM AUTHOR]

Zinc (Zn) isotope data for mid-ocean ridge basalts (MORB) are scarce. The possible effects of MORB differentiation and mantle compositional heterogeneity on MORB Zn isotope compositions are poorly understood. In this paper, we report Zn isotope data of MORB lavas from the East Pacific Rise (EPR) at 10°30′N, which are understood to have been derived by a similar extent of melting from a compositionally uniform mantle source but manifest significantly varying extents of magma differentiation (MgO = 7.38–1.76 wt%) to demonstrate unequivocal Zn isotope fractionation during MORB differentiation. These lavas have a small δ66Zn (relative to the JMC-Lyon standard) range of 0.21–0.32‰, with an average of 0.26 ± 0.07‰ (2SD, N = 24), overlapping with literature data. However, δ66Zn values show significant correlations with indices of magma differentiation (e.g., MgO and CaO), with the more differentiated samples having isotopically heavier Zn. We can thus conclude that MORB differentiation can lead to ∼0.1‰ δ66Zn elevation, which is similar to that observed in Hawaiian Kilauea Iki lava lake samples. Fractional crystallization of olivine and clinopyroxene at MgO > ∼3.5 wt% and clinopyroxene and Fe–Ti oxides dominated by ilmenite at MgO < ∼3.5 wt% results in the observed Zn isotope fractionation. The δ66Zn values for primitive N-MORB and MORB source mantle are estimated to be ∼0.22‰ and ∼0.17‰, respectively. Furthermore, we observe a positive correlation between δ66Zn and [La/Sm] N in primitive (MgO = 7.58–9.01 wt%) literature MORB, indicating the existence of possible Zn isotope heterogeneity in the oceanic upper mantle. We thus predict heavy Zn isotope enrichment in mantle sources for E-MORB samples with high [La/Sm] N , which requires future testing. [ABSTRACT FROM AUTHOR]

Variability of nanometer-size devices is a major challenge for circuit design. Apart from the as-fabricated variability, the postfabrication degradation introduces a time-dependent variability, originating from statistical distribution of charge location and number. The existing characterization techniques do not always capture the maximum degradation. Some of them does not separate the device-to-device variation from the charging fluctuation within the same device, either. The objective of this paper is to develop a new analysis method for characterizing time-dependent device-to-device variation, accounting for within-device fluctuation (TVF). The TVF captures the maximum degradation, separate device-to-device variation from within-device fluctuation, and reduce the data points by three orders of magnitude. It is shown that the popular data acquisition at discrete time points does not capture the fluctuation well and drain current must be measured continuously. The TVF shows that degradation has two components—a fluctuation with time and one whose discharge is not observed under a given bias. Although both of them increase with stress time, the correlation between them is weak, indicating two different origins. [ABSTRACT FROM AUTHOR]

Hydrogenation of alkenes is one of the most fundamental transformations in organic synthesis, and widely used in the petrochemical, pharmaceutical, and food industries. Although numerous hydrogenation methods have been developed, novel types of catalysis with new mechanisms and new hydrogen sources are still desirable. Thioxanthone (TX) is widely used in energy‐transfer photoreactions, but rarely in photoredox processes. Herein we show that a catalytic amount of TfOH as a co‐catalyst can tune the properties of TX to make it a photoredox catalyst with highly enhanced oxidative capability in the hydrogenation of carbonylated alkenes with the cheap petroleum industrial product p‐xylene serving as the hydrogen source. Deuterium can also be introduced by this method by using D2O as the D source. To the best of our knowledge, this is the first example of using p‐xylene as a hydrogen source. [ABSTRACT FROM AUTHOR]

Hydrogenation of alkenes is one of the most fundamental transformations in organic synthesis, and widely used in the petrochemical, pharmaceutical, and food industries. Although numerous hydrogenation methods have been developed, novel types of catalysis with new mechanisms and new hydrogen sources are still desirable. Thioxanthone (TX) is widely used in energy‐transfer photoreactions, but rarely in photoredox processes. Herein we show that a catalytic amount of TfOH as a co‐catalyst can tune the properties of TX to make it a photoredox catalyst with highly enhanced oxidative capability in the hydrogenation of carbonylated alkenes with the cheap petroleum industrial product p‐xylene serving as the hydrogen source. Deuterium can also be introduced by this method by using D2O as the D source. To the best of our knowledge, this is the first example of using p‐xylene as a hydrogen source. [ABSTRACT FROM AUTHOR]

Defects in gate oxide cause breakdown and shorten device lifetime. Early works mainly focused on generation process that converts a precursor into a charged defect. Although it can be neutralized through “recovery,” the defect is still there and will recharge when resuming stress. Recently, we have shown that this is not always the case and some defects can be lost, but a detailed investigation is missing. The central objective of this work is to accurately define and extract the loss, separate it from slowdown, and evaluate their enhancement of device lifetime. Loss is defined as elimination of defects, while slowdown means that recharging a “hardened” precursor takes longer than charging a fresh one. Clear evidences show that losses originate from permanent components, i.e., generated interface states and antineutralization positive charges, while slowdown occurs to both permanent and recoverable components. Loss is thermally accelerated, but slowdown of recoverable component is not. This improved understanding adds slowdown and losses to the existing framework for defects. For the first time, we report that the losses and slowdown enhance device lifetime by a factor of 2.6–4.3, for an allowed threshold voltage shift of 20–45 mV. [ABSTRACT FROM AUTHOR]

Abstract: Five cadinane sesquiterpenoids, named stereumin A (1), B (2), C (3), D (4) and E (5) were isolated from the CHCl3 extract of the culture broth of the fungal strain CCTCC AF 207024. Based on the sequences at the internal transcribed spacer (ITS) region and partial 28S rDNA, this fungus was identified as a Stereum sp. The structures of the five compounds were elucidated using spectroscopic data from 1D, 2D NMR and HRESIMS experiments, and the structures of 1 and 2 were further confirmed by single-crystal X-ray diffraction analysis. Compounds 1–5 showed nematicidal activities against the nematode Panagrellus redivivus at 400 mg l−1. Among these five compounds, compounds 3 and 4 killed 84.4% and 94.9% of P. redivivus, respectively in 48h. [Copyright &y& Elsevier]

Purpose: The purpose of this article is to understand the current research status and future development trends in the field of numerical simulation on rock mass grouting. Design/methodology/approach: This article first searched the literature database (EI, Web of Science, CNKI, etc.) for keywords related to the numerical simulation of rock mass grouting to obtain the initial literature database. Then, from the initial database, several documents with strong relevance to the numerical simulation theme of rock mass grouting and high citation rate were selected; some documents from the references were selected as supplements, forming the sample database of this review study (a total of 90 articles). Finally, through sorting out the relationship among the literature, this literature review was carried out. Findings: The numerical simulation of rock mass grouting is mainly based on the porous media model and the fractured media model. It has experienced the development process from Newtonian fluid to non-Newtonian fluid, from time-invariant viscosity to time-varying viscosity, and from generalized theoretical model to engineering application model. Based on this, this article summarizes four scientific problems that need to be solved in the future in this research field: the law of grout distribution at the cross fissures, the grout diffusion mechanism under multi-field coupling, more accurate grouting theoretical model and simulation technology with strong engineering applicability. Originality/value: This research systematically analyzes the current research status and shortcomings of numerical simulation on rock mass grouting, summarizes four key issues in the future development of this research field and provides new ideas for the future research on numerical simulation on rock mass grouting. [ABSTRACT FROM AUTHOR]

• The sliding mode is fast continuous and nonsingular. • The controller reduces the chattering and renders high-precision performance. • The corresponding parameters are easy to adjust. • The conservativeness of the proposed controller is reduced. • The stability and robustness have been verified by the simulation and experiments. In this paper, a fast terminal sliding mode controller is designed for an active suspension gravity compensation system with unknown bounds of uncertainties and disturbances. A robust finite-time convergence estimator is used to estimate the velocity and the disturbances. The estimator can guarantee that the speed of the estimation errors converge faster than the displacement tracking errors by regulating its gains. The corresponding stability and robustness of the closed-loop system are proved. In particular, the proposed control scheme can reduce the chattering effectively and render the high-precision tracking performance that have been verified by the simulation and experiments. [ABSTRACT FROM AUTHOR]

Time series of ground subsidence can not only be used to describe motion produced by various anthropocentric and natural process but also to better understand the processes and mechanisms of geohazards and to formulate effective protective measures. For high-accuracy measurement of small baseline subset interferometric synthetic aperture radar (SBAS-InSAR), atmospheric turbulence and decorrelation noise are regarded as random variables and cannot be accurately estimated by a deterministic model when large spatio-temporal variability presents itself. Various weighting methods have been proposed and improved continuously to reduce the effects of these two parts and provide uncertainty information of the estimated parameters, simultaneously. Network-based variance-covariance estimation (NVCE) and graph theory (GT) are the two main weighting methods which were developed on the basis of previous algorithms. However, the NVCE weighting method only focuses on the influence of atmospheric turbulence and neglects the decorrelation noise. The GT method weights each interferogram in a time series by using the Laplace transformation. Although simple to implement, it is not reasonable to have an equal weight for each pixel in the same interferogram. To avoid these limitations, this study presents a new weighting method by considering the physical characteristics of atmospheric turbulence and decorrelation noise in SBAS-InSAR images. The effectiveness of the proposed method was tested and validated by using a set of simulated experiments and a case study on a Hawaiian island. According to the GPS-derived displacements, the average RMSE of the results from the new weighting method was 1.66 cm, indicating about an 8% improvement compared with 1.79, 1.80 and 1.80 cm from the unweighted method, the NVCE method and the GT method, respectively. [ABSTRACT FROM AUTHOR]

Water vapor is the most variable constituent in the atmosphere and plays an important role in climate studies, mesoscale meteorology modeling and numerical weather forecasting. Being able to penetrate clouds, interferometric synthetic aperture radar (InSAR) shows great potential in atmospheric water vapor mapping. But InSAR can only measure differential water vapor between two acquisitions. In this paper, we formulate a general framework by constructing the Gauss-Markov model and developing the estimation method to retrieve the non-differential water vapor from Small BAseline Subset InSAR (SBAS-InSAR). To address the rank-deficiency in the Gauss-Markov model, we propose a new constraint, i.e., the temporal mean of water vapor being invariant. Simulated and real data experiments are conducted to validate the effectiveness of the framework and the advantages of the proposed constraint. The results show that the new constraint can offer an estimation more robust than the two traditional ones, i.e., the temporal mean of water vapor being zero and single or multiple epoch water vapor referencing. In addition, we found that there exists a constant bias, which equals to the temporal mean of water vapors, between the solutions under the new constraint and that under the constraint of the temporal mean of water vapor being zero. Finally, the possible methods to evaluate the temporal mean of water vapor are discussed. • Formulating a general framework and developing the estimation method to retrieve the non-differential PWV from TS-InSAR. • Proposing a new constraint to address the rank-deficiency in Gauss-Markov model. • Funding a constant bias between the solutions under the new constraint and that under one of the existing constraints. • Proving the equivalency between the new method and the rule of minimum-norm least-squares. [ABSTRACT FROM AUTHOR]

Nanocrystalline surface layers and gradient nanostructures are produced in AZ31 Mg alloy through surface mechanical attrition treatment (SMAT). The grain sizes in the surface layer of the alloy are significantly refined to a nanoscale after SMAT. A gradient nanostructure is formed in which the grain size increases gradually from surface to matrix. The microhardness of the surface layer and the tensile strength of the alloy are significantly improved, but with a certain loss of fracture elongation. SEM photographs of tensile fracture of samples after SMAT show that the fractures of the GNS layer are brittle fractures with poor toughness, while the plasticity of the matrix is better, and the fractures exhibit typical ductile features. To investigate the effect of SMAT on the textural evolution of AZ31 Mg alloy, electron backscatter diffraction is used to analyze the as-received sample and samples after SMAT. The non-basal plane orientation is increased and the basal texture is significantly weakened in the fine-grained layer after SMAT. The weakening of the basal texture reduces the anisotropy of the mechanical properties of Mg alloys, which is beneficial for their industrial application. • The texture gradient of gradient nanostructured AZ31 magnesium was found by electron backscatter diffraction. • The grain refinement mechanism of gradient nanostructure AZ31 magnesium alloy was obtained. • The microstructural evolution of gradient nanostructured AZ31 magnesium alloy was displayed. [ABSTRACT FROM AUTHOR]

• HPV16 infection is the most prevalent in Tianjin which is tightly relevant to cervical cancer progression. • E-p variant is the most prevalent type followed by As variant in Tianjin urban healthy women screening. • As variant appears higher carcinogenic potential than E-p, and is positively related to the severity of cervical lesions. • E-G350 was only detected in HSIL and cervical cancer, indicating E-G350 is possibly related to elevated risk of lesions. The aim of this study is to investigate distribution of human papillomavirus (HPV) 16 variants in screening healthy women and the potential association between HPV 16 variants and progression of cervical lesions. For this study a total of 2000 healthy women in Tianjin urban area and 212 patients who were HPV 16 positive and underwent colposcopy were analyzed for HPV 16 variants by pyrosequencing. The results show that the HPV 16 was the most prevalent genotype in Tianjin healthy women and five HPV 16 variant types were detected. The HPV 16 variants were determined by sequencing parital E6 region and the detected variants were European prototype E-T350 (E-p), E-G350, E-C109 G, Asian (As) and Asian-American (AA), among which the E-p variant was the most prevalent (82.76%) followed by As variant. Interestingly, in patients with suspected cervical lesions the most prevalent variant was As variant (54.9%) by increasing significance with severity of cervical diseases (OR 4.337; 95% CI 1.248–15.067; P = 0.021), and followed by HPV 16 E-p variant while E-G350 variant only appeared in HSIL and cervical cancer. Our results show that HPV 16 E-p variant was more prevalent than As in Tianjin healthy screening women while As variant was the most frequently type in HSIL and cervical cancer. It is suggested that the mutation of HPV 16 Asian variants, comparing with HPV 16 E-p variants, might contribute to the transformation from HPV 16 persistent infection to cervical cancer. [ABSTRACT FROM AUTHOR]