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Enamel coating, which is of low thermal conductivity and high chemical stability, has been employed for the protection of many hot parts against oxidation. It is composed of multiple oxides, and each oxide component plays a certain role on thermophysical properties. In this paper, a type of silicate enamel coating with different contents of oxide component Al 2 O 3 was prepared on K444 superalloy. Its microstructural evolution and cyclic oxidation behavior at 1000 °C were investigated. Results indicated that the A0 enamel coating, which was free of Al 2 O 3 in composition, suffered from serious crystallization at high temperature. The formation of quartz, cristobalite and SrSiO 3 crystals resulted in significant mass loss during cyclic oxidation. However, precipitation of these crystals was almost completely prohibited in the A10 and A15 coatings with 10 and 15 wt% Al 2 O 3 , respectively. The A10 coating had no mass loss after cyclic oxidation. But much high content of Al 2 O 3 resulted in the formation of abundant long strip crystals of SrAl 2 Si 2 O 8 in the A15 coating, which led to minor spallation. Furthermore, enamel coatings with Al 2 O 3 (above 6 wt%) promoted the formation of a continuous alumina scale at the enamel/alloy interface, which improved oxidation resistance and increased bonding strength. The well grown alumina scale at interface as well as the mild crystallization ensured high spallation resistance of the enamel coating A10. [ABSTRACT FROM AUTHOR]

The aging of microplastics (MPs) is extremely influenced by photochemically-produced reactive intermediates (PPRIs), which are mediated by natural photosensitive substances. Algal extracellular polymeric substances (EPS) can produce PPRIs when exposed to sunlight. Nonetheless, the specific role of EPS in the aging process of MPs remains unclear. This work systematically explored the aging process of polystyrene (PS) MPs in the EPS secreted by Chlorella vulgaris under simulated sunlight irradiation. The results revealed that the existence of EPS accelerated the degradation of PS MPs into particles with sizes less than 1 µm, while also facilitating the formation of hydroxy groups on the surface. The release rate of dissolved organic matter (DOM) from PS MPs was elevated from 0.120 mg·L-1·day-1 to 0.577 mg·L-1·day-1. The primary factor contributing to the elevated levels of DOM was humic acid-like compounds generated through the breakdown of PS. EPS accelerated the aging process of PS MPs by primarily mediating the formation of triplet excited states (3EPS*), singlet oxygen (1O 2), and superoxide radicals (O 2 ∙-), resulting in indirect degradation. 3EPS* was found to have the most substantial impact. This study makes a significant contribution to advance understanding of the environmental fate of MPs in aquatic environments impacted by algal blooms. [Display omitted] • Algae EPS greatly enhanced the microplastic (MP) aging under simulated sunlight. • Photoaging of MP induced by EPS led to changes in MP physicochemical properties. • 3EPS*, 1O 2 , and O 2 ∙- mediated by EPS contributed to the MP aging. • 3EPS* was the dominant specie for accelerating the aging process of MPs. [ABSTRACT FROM AUTHOR]

Herein, a multicomponent bioactive glass (0Z, 46SiO 2 –30CaO–18Na 2 O–6P 2 O 5 , wt.%) is prepared via melting. ZrO 2 is introduced into the bioglass using two different methods, and then three types of glass-ceramic bulks are manufactured using low-cost pressureless sintering. The effect of ZrO 2 addition on the bioactivity and mechanical properties of the bioactive glass-ceramic is assessed. The results indicate that the main crystalline precipitate from the bioactive glass-ceramic is Na 2 Ca(Si 2 O 6). The crystallisation ability of the 5Z glass-ceramic, bioactive glass-ceramic with ZrO 2 added during melting at high temperature, is reduced because ZrO 2 participated in the reconstruction of the glass network. Further, the ZrO 2 addition led to a low rate of cation release when soaked in simulated body fluid, indicating a decreased bioactivity. At the same time, the 5Y bioactive glass-ceramic, prepared by mixing YSZ particles with 0Z using ball-milling, possesses not only the highest mechanical strength (about twice the strength of 0Z) but also a high bioactivity. This study presents a promising method for the production of excellent bioactive glass-ceramic and a candidate (5Y) for the clinical applications where load bearing is required. [ABSTRACT FROM AUTHOR]

In this paper, we study the reaction–diffusion equations with variable coefficients in some bounded domains. At least one of the components of solutions blows up for every initial data in some exponent regions, where the Fujita exponents are determined by the exponents of the sources and the coefficients and the dimension of the domain. We also show the classifications of simultaneous and nonsimultaneous blow-up of the components of solutions. The asymptotic properties are discussed including blow-up rates and sets. Moreover, the upper and the lower bounds of blow-up time are given for all dimensions of domains, respectively. [ABSTRACT FROM AUTHOR]

The Callovian–Oxfordian carbonates in the northeastern Amu Darya Basin of southeastern Turkmenistan, are composed of medium-to thick-bedded, mostly grainy limestones with various skeletal (bivalves, brachiopods, echinoderms, foraminifera, corals, and sponge) and non-skeletal grains (intraclasts, ooids, and peloids). The 6 microfacies types recognized in the Callovianand and 18 microfacies types in Oxfordian carbonates are grouped into two depositional phases, ramp and platform. The Callovian carbonates were deposited on a carbonate ramp, which evolved into a depositional platform in the Oxfordian. The main components of the Oxfordian platform margin complex are reefs and shoals. The principal reef builders are corals, algae and sponges. Regional tectonic movements, eustatic sea-level changes and sedimentation rates were the primary controlling factors of facies evolution during the Callovian–Oxfordian time in the northeastern Amu Darya Basin. [ABSTRACT FROM AUTHOR]

This paper considers both quenching and blowup phenomena to the coupled parabolic equations with zero Dirichlet boundary. Here, one component of the solution represents the density of some chemical and the other denotes its temperature in some ignition process. All the singular phenomena have been obtained including simultaneous and nonsimultaneous blow-up or quenching, which are classified completely by the exponents. The results extend the ones in the previous paper (Liu and Chan, 2011). [ABSTRACT FROM AUTHOR]

This paper deals with simultaneous blow-up solutions to a Dirichlet initial–boundary problem of the parabolic equations u t = div ( a ( x ) ∇ u ) + ∫ Ω u m v s d x and v t = div ( b ( x ) ∇ v ) + ∫ Ω u q v p d x in Ω × [ 0 , T ) . We complete the previous known results by covering the whole range of possible exponents. Then uniform blow-up profile is obtained for all simultaneous blow-up solutions through proving new rules for some auxiliary systems. At last, boundary layer is studied. [ABSTRACT FROM AUTHOR]

Iron oxides play an important role in the transport and transformation of organic phosphorus in aquatic environments. However, the effect of different types of iron oxide on the environmental fate of organic phosphorus has remained unclear. In this study, the photodegradation of the organic phosphorus compound adenosine triphosphate (ATP) via the activity of crystalline (goethite) and amorphous (ferrihydrite) iron oxides was investigated. It was found that ATP was photodegraded by goethite, resulting in the release of dissolved inorganic phosphate under simulated sunlight irradiation. The concentration of ATP on goethite decreased by 75% after 6 h of simulated sunlight irradiation, while the concentration of ATP on ferrihydrite decreased by only 22%. ATR-FTIR spectroscopy revealed that the intensity of the peaks for the P–O and P O stretching vibrations in the goethite−ATP complex decreased significantly more after simulated sunlight irradiation than did those for the ferrihydrite treatment. Combined with the higher TOC/TOC 0 values for the goethite treatment, the results indicate that a more vigorous photochemical reaction took place in the presence of goethite than with ferrihydrite. Reactive oxygen species analysis also showed that hydroxyl and superoxide anion radicals were generated when goethite was exposed to simulated sunlight irradiation, while ferrihydrite did not exhibit this ability. Overall, this study highlights that the type of iron oxide is an important factor in the transformation of organic phosphorus in aquatic environments. [Display omitted] • Transformation of organic phosphorus after adsorption was investigated. • Organic phosphorus adsorbed on goethite underwent photodegradation. • •OH and O 2 •− generated on the gothite, but not ferrihydrite. • Iron minerals mediated the environmental fate of organic phosphorus. [ABSTRACT FROM AUTHOR]

The distinctive features of the Lower Devonian rocks of the Longmenshan area in southwestern China are brachiopod shell concentrations, especially in the Bailiuping, Ganxi and Xiejiawan Formations, where brachiopod shell concentrations occur widely throughout. Depending on the dominant skeletal elements, six types of shell concentrations can be distinguished: Protochonete , Acrospirifer , Howellella , Orientospirifer , polyspecific shell and polyspecific fragments concentrations. According to the shell features, taphonomic signature, host sediments and their relationships, four genetic models of the various shell concentrations are described in this paper. The genetic processes and distributions along an onshore–offshore area were clarified on the base of taphonomic analysis. Pavements of opportunistic species of Protochonetes are autochthonous assemblages living in quieter, deeper, more offshore waters near the maximum storm wave base. The pavements are the result of reduced sedimentation; the substrate was silty and water-saturated with variable turbidity soupy-mud. Transport by high-energy processes is interpreted as the final formation process of polyspecific fragments concentrations with most extensive scope from intertidal zone to the maximum storm wave base. The Acrospirifer , Howellella , and Orientospirifer concentrations have been stirred by storm wave action and quickly buried after short transport tempestite model. They are most easily preserved around the average storm wave-base. The polyspecific shell concentrations, which include large bivalves are autochthonous assemblages living in shallow and relatively quieter water near shore environments. Autochthonous assemblages of the opportunist Protochonetes bailiupingensis occurring in the Bailiuping Formation of the Longmenshan area not only record of storm events, but are also important features to identify and correlate the Bailiuping Formation in the field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Apatite fission-track analysis indicates a multi-stage exhumation history. • There are four peaks are interpreted as significant regional uplift episodes. • Statistical results suggest close relationship between exhumation and uranium mineralization. • Late Cretaceous–early Paleogene and latest Miocene-Present are main mineralization episodes. The phases of tectonic activity and exhumation of the southern margin of the Junggar Basin during the Cretaceous through Cenozoic shows significant relationships with the timing of uranium mineralization episodes. To clarify the succession of metallogenetic stages that were controlled by different phases of uplift and exhumation, apatite fission track (AFT) thermochronology was performed on the Jurassic through Cenozoic sediments from the Manas section in the southern Junggar Basin. The mean ages of the AFT suites range from 63 Ma to 133 Ma, and are younger than the host sediment for the Mesozoic samples and older than the host for the Cenozoic samples. The mean track lengths (MTLs) are between 10 and 11 μm. These results indicate that most of the apatite grain assemblages in these samples experienced complicated annealing histories. AFT ages were combined with thermal history modeling to unravel the timing of the multi-phase regional uplift and exhumation history and to reveal the tectonic constraints on the uranium mineralization. The populations of AFT single-grain ages display four peaks, which are interpreted as regional uplift and cooling episodes: mid-Early Jurassic (189–180 Ma), late Jurassic–early Cretaceous (157–116 Ma), late Cretaceous–early Paleocene (88–59 Ma) and late Eocene–early Oligocene (37–28 Ma). Thermal history modeling indicates two episodes of rapid cooling of the basin sediment deposits during the late Cretaceous–Paleocene (80–50 Ma) and the Pliocene (5 Ma)–Present. A synthesis of the temporal relationship between AFT age peaks, of the modeled time–temperature paths, of a compilation of age data and regional geologic events from the Tianshan mountain belt, suggests a close relationship between tectonic evolution and uranium mineralization. Uranium metallogenesis episodes occurred in conjunction with tectonic uplift and exhumation episodes along the southern margin of the Junggar Basin during the late Cretaceous–early Paleogene and during the latest Miocene-Present. The earlier episode was the primary mineralization stage, and the later episode was a partial transformation stage superimposed on the earlier one. [ABSTRACT FROM AUTHOR]

During the Cenozoic a typical lacustrine tempestite deposition was developed in the Lulehe and Xichagou sections of the Qaidam Basin. The sedimentary structures of these two sections above are examined here in detail, which consist of storm erosion, storm tear, storm wave and rapid storm-generated sedimentary structures after storm processes, such as groove casts, scour structures, cutoff structures, hummocky cross-stratification (HCS), parallel bedding and graded bedding. On the basis of these sedimentary characteristics and the vertical facies sedimentary sequence, the causes of the sedimentary succession are analyzed and a Cenozoic sedimentary model of the Qaidam Basin containing shallow proximal, transitional and deep distal tempestites is established. According to the tempestite scale and HCS wavelength, the Cenozoic storm was obviously more intense in the basin's Upper Ganchaigou formation than that in the Lower Youshashan formation. This variation indicates that a paleoclimatic transition largely corresponded with the second uplift of the whole Qinghai-Tibet Plateau. The discovery of a Cenozoic tempestite in the Qaidam Basin is significant in the paleogeographic, paleoclimate and paleostructural fields, which provides a new insight in further study of the Qinghai-Tibet Plateau uplift. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reflux seepage, burial and hydrothermal types of dolomite in the Cambrian Sanshanzi Formation are petrographically and geochemically identified. • Reflux seepage dolomitization was formed by high-salinity and Mg2+-enriched fluid penetrates downward into the limestone, and the dolomite has low δ 13C, high Sr and low Mn contents. • Burial dolomitization was due to the limestone deeply buried during the diagenetic stage and formed under a high-temperature and pressure environment. • Hydrothermal dolomitization occurred during Mg2+-rich hydrothermal fluid invaded, and the dolomite characterized by saddle dolomite with a positive δ Eu anomaly, and a low δ 18O value. The Cambrian Sanshanzi Formation is an important dolomite horizon in the Ordos Basin of northern China, and is well exposed in the western part of that basin. This paper focuses on the petrography and geochemistry of dolomites in this formation with an aim to provide a better understanding of their genesis. Reflux seepage, burial, and hydrothermal dolomites are identified in the Sa nshanzi Formation. Reflux seepage dolomites include dolomitic grainstone and powder crystal dolomite, and have high Sr and low Mn contents, a high CaO/MgO ratio and low δ 13 C values, and the reflux seepage dolomitization was formed by high-salinity and Mg2+-enriched fluid penetrates downward into the limestone. Burial dolomites are the main type of dolomite distributed through the Sanshanzi Formation. Burial dolomites are composed of fine- to coarse-crystal dolomite and have low Sr and high Mn contents, a low CaO/MgO ratio, and high δ 13C values. The features of high salinity, strong reducibility and negative δ 18O values indicate the burial dolomites formed under high-temperature and high-pressure conditions, the burial dolomitization was due to the limestone deeply buried during the later diagenetic stage. Hydrothermal dolomites are mainly characterized by saddle dolomite features, a positive δ Eu anomaly, and low δ 18O values, and the hydrothermal dolomitization occurred during Mg2+-rich hydrothermal fluid invaded. The reflux seepage and hydrothermal dolomite developed in local areas, with the hydrothermal dolomite affected by the distribution of faults. [ABSTRACT FROM AUTHOR]

Abstract: This paper considers blow-up solutions for reaction–diffusion equations, complemented by homogeneous Dirichlet boundary conditions. It is proved that there exist initial data such that one block or two (separated or contiguous) blocks of components blow up simultaneously while the others remain bounded. As a corollary, a necessary and sufficient condition is obtained such that any blow-up must be the case for at least two components blowing up simultaneously. We also show some other exponent regions, where any blow-up of components must be simultaneous. Moreover, the corresponding blow-up rates and sets are discussed. The results extend those in Liu and Li [B.C. Liu, F.J. Li, Non-simultaneous blow-up of components for nonlinear parabolic systems, J. Math. Anal. Appl. 356 (2009) 215–231]. [Copyright &y& Elsevier]

Abstract: This paper deals with u t =Δu + u m (x, t)e pv(0,t), v t =Δv + u q (0, t)e nv(x,t), subject to homogeneous Dirichlet boundary conditions. The complete classification on non-simultaneous and simultaneous blow-up is obtained by four sufficient and necessary conditions. It is interesting that, in some exponent region, large initial data u 0(v 0) leads to the blow-up of u(v), and in some betweenness, simultaneous blow-up occurs. For all of the nonnegative exponents, we find that u(v) blows up only at a single point if m >1(n >0), while u(v) blows up everywhere for 0⩽ m ⩽1 (n =0). Moreover, blow-up rates are considered for both non-simultaneous and simultaneous blow-up solutions. [Copyright &y& Elsevier]

Abstract: This work deals with non-simultaneous and simultaneous blow-up solutions for , , subject to homogeneous Dirichlet boundary conditions. We obtain the complete results of non-simultaneous and simultaneous blow-up solutions for any fixed point in any general bounded domain. The critical exponents of non-simultaneous blow-up are proposed. [Copyright &y& Elsevier]

Abstract: This paper deals with blow-up solutions in parabolic equations coupled via nonlocal nonlinearities, subject to homogeneous Dirichlet conditions. Firstly, some criteria on non-simultaneous and simultaneous blow-up are given, including four kinds of phenomena: (i) the existence of non-simultaneous blow-up; (ii) the coexistence of non-simultaneous and simultaneous blow-up; (iii) any blow-up must be simultaneous; (iv) any blow-up must be non-simultaneous. Next, total versus single point blow-up are classified completely. Moreover, blow-up rates are obtained for both non-simultaneous and simultaneous blow-up solutions. [Copyright &y& Elsevier]

Abstract: This paper deals with localized parabolic equations , with homogeneous Dirichlet boundary conditions, where is any fixed point in a bounded domain of . The optimal classification of non-simultaneous and simultaneous blow-up phenomena is proposed for all of the nonnegative exponents. Moreover, uniform blow-up profiles are obtained for all kinds of simultaneous blow-up solutions. [Copyright &y& Elsevier]

Abstract: This paper deals with the non-simultaneous and simultaneous blow-up for some parabolic systems coupled via nonlinear boundary flux . For radially symmetric solutions, we obtain that one component can blow up by itself and may provide sufficient help to the blow-up of the other ones under suitable initial data. In particular, such phenomena happen for every initial data in some exponent regions. It is interesting that there exist initial data such that any two components blow up simultaneously, either of which blows up depending on itself and also can give sufficient help to the other components blowing up simultaneously. A necessary and sufficient condition is obtained on the simultaneous blow-up of at least two components for all initial data. Moreover, the non-simultaneous and simultaneous blow-up rates and sets are determined. [Copyright &y& Elsevier]

Abstract: This paper deals with simultaneous and non-simultaneous blow-up solutions for heat equations coupled via exponential sources, subject to null Dirichlet boundary conditions. The main results complete the previously known results on the optimal classification for simultaneous and non-simultaneous blow-up solutions by covering the whole ranges of exponents. Moreover, all kinds of simultaneous and non-simultaneous blow-up rates are obtained. [Copyright &y& Elsevier]

Abstract: The critical exponents are established for a nonlinear diffusion system with convection, which are described clearly by the signs of two parameters solving the so-called characteristic algebraic system. It is proved that the convection plays an important role in determining the critical properties of solutions in the balance case. This greatly improves the authors’ previous paper for the same model. [Copyright &y& Elsevier]

Abstract: The paper deals with the radially symmetric solutions of , , subject to null Dirichlet boundary conditions. For the blow-up classical solutions, we propose the critical exponents for non-simultaneous blow-up by determining the complete and optimal classification for all the non-negative exponents: (i) There exist initial data such that () blows up alone if and only if (), which means that any blow-up is simultaneous if and only if , . (ii) Any blow-up is () blowing up with () remaining bounded if and only if , (, ). (iii) Both non-simultaneous and simultaneous blow-up may occur if and only if , . Moreover, we consider the blow-up rate and set estimates which were not obtained in the previously known work for the same model. [Copyright &y& Elsevier]

Abstract: This work deals with heat equations coupled via nonlinear boundary flux which obey different laws. We give a complete classification for non-simultaneous and simultaneous blow-up by covering all of the possible exponents. [Copyright &y& Elsevier]

Abstract: This paper deals with heat equations coupled via nonlinear boundary flux , , . A necessary and sufficient condition for the existence of only one component blowing up for nondecreasing in time and radially symmetric solutions. Three kinds of exponent regions are obtained as follows, (i) only one component blows up for every initial data; (ii) the existence of two components blowing up simultaneously while the third one remains bounded, also with two kinds of blow-up rates and ; (iii) e.g.,  remains bounded and blow up simultaneously with blow-up rate for every initial data. Moreover, the eight kinds of simultaneous blow-up rates and blow-up sets are discussed. [Copyright &y& Elsevier]

Oolitic ironstones are widely distributed in South China, particularly in Middle and Upper Devonian strata, and are referred to as Ningxiang-type iron deposits. The hybrid siliciclastic-carbonate deposits of the Lower Devonian Yangmaba Formation iron-enriched interval (dominated by hematite ooids and chamosite ooids) are recognized in the Shigouli section of the Longmenshan area, Sichuan Basin. The Yangmaba Formation ironstones differ from other Devonian Ningxiang-type oolitic ironstones: The Ninxiang-type ironstone deposits are commonly interpreted to have been deposited in a narrow coastal zone or inland restricted bays and lagoons with clastic and carbonate sedimentary sequences; by contrast, the studied oolitic ironstones are interpreted to have been deposited in a shoreface zone to inner shelf based upon field and petrographic investigations. Our study shows that this oolitic ironstone consists of dominantly hematite ooids and chamosite ooids. Major element and trace element discrimination diagrams, PAAS (Post-Archaean average Australian sedimentary rock) normalized REE (Rear earth element) patterns, and positive Ce/Ce* anomalies show evidence of a hydrogenous origin. The weathering of adjacent terrestrial rocks from the formation of the palaeo-land surface is interpreted to be the main Fe source for the oolitic ironstones. Environmental energy and redox conditions are the important factors controlling ironstone formation and distribution of the hybrid deposits of the Yangmaba Formation in the Shigouli section of the Longmenshan area. Oolitic ironstones formed in oxidizing conditions of the upper shoreface zone include the carbonate concentric ooids with slightly hematite ooids occurring in higher energy upper oxidizing shoreface subzone, moderately hematite concentric ooids deposited in middle oxidizing shoreface subzone of fluctuant environmental energy, and hematite ooids present in lower oxidizing shoreface subzone of lower-energy conditions or weakly agitated environment. The chamosite concentric ooids and superficial ooids formed in reducing conditions of the lower shoreface and upper offshore transition. The former occurred in upper reducing shoreface subzone near the fair weather wave base, and the chamosite superficial ooids were deposited in lower reducing shoreface subzone and upper offshore transition that was affected by episodic high energy events. • Chamositic and hematitic ooids were deposited in the early Devonian. • The distribute model of ferruginous ooids that deposited in shoreface has been built in hybrid deposition. • Hydrodynamic and redox conditions are the important control factors of ferruginous ooids formation and distribution. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the blow-up behavior of radial solutions to a parabolic system multi-coupled via inner sources and boundary flux. We first obtain a necessary and sufficient condition for the existence of non-simultaneous blow-up, and then find five regions of exponent parameters where both non-simultaneous and simultaneous blow-up may happen. In particular, nine simultaneous blow-up rates are established for different regions of parameters. It is interesting to observe that different initial data may lead to different simultaneous blow-up rates even with the same exponent parameters. [Copyright &y& Elsevier]

Abstract: This paper deals with a reaction-diffusion equation with inner absorption and boundary flux of exponential forms. The blow-up rate is determined with the blow-up set, and the blow-up profile near the blow-up time is obtained by the Giga–Kohn method. It is observed that the blow-up rate and profile are independent of the nonlinear absorption term. [Copyright &y& Elsevier]

Haplogroup G predisposes one to an increased risk of osteoarthritis (OA) occurrence, while haplogroup B4 is a protective factor against OA onset. However, the underlying mechanism is not known. Here, by using trans-mitochondrial technology, we demonstrate that the activity levels of mitochondrial respiratory chain complex I and III are higher in G cybrids than in haplogroup B4. Increased mitochondrial oxidative phosphorylation (OXPHOS) promotes mitochondrial-related ATP generation in G cybrids, thereby shifting the ATP generation from glycolysis to OXPHOS. Furthermore, we found that lower glycolysis in G cybrids decreased cell viability under hypoxia (1% O 2 ) compared with B4 cybrids. In contrast, G cybrids have a lower NAD + /NADH ratio and less generation of reactive oxygen species (ROS) under both hypoxic (1% O 2 ) and normoxic (20% O 2 ) conditions than B4 cybrids, indicating that mitochondrial-mediated signaling pathways (retrograde signaling) differ between these cybrids. Gene expression profiling of G and B4 cybrids using next-generation sequencing technology showed that 404 of 575 differentially expressed genes (DEGs) between G and B4 cybrids are enriched in 17 pathways, of which 11 pathways participate in OA. Quantitative reverse transcription PCR (qRT-PCR) analyses confirmed that G cybrids had lower glycolysis activity than B4 cybrids. In addition, we confirmed that the rheumatoid arthritis pathway was over-activated in G cybrids, although the remaining 9 pathways were not further tested by qRT-PCR. In conclusion, our findings indicate that mtDNA haplogroup G may increase the risk of OA by shifting the metabolic profile from glycolysis to OXPHOS and by over-activating OA-related signaling pathways. [ABSTRACT FROM AUTHOR]

This paper deals with a parabolic p (x) -Laplace equation with logarithmic source u q (x) log u. The singular properties of solutions are determined completely by classifying the initial energy. Moreover, we obtain a new extinction rate of solutions, where the order of the extinction rate is greater than the maximum of variable exponent q (x). This kind of extinction rate could reflect the influence of logarithmic functions on the extinction of solutions more reasonably. [ABSTRACT FROM AUTHOR]

During the Middle Ordovician, the Great Ordovician Biodiversification Event (GOBE) saw an accelerated diversification pulse in the marine metazoan richness, which has been linked to the oceanic and climatic changes. Here we have examined a deep-water slope succession, Xijinhe section, in Lower Yangtze region by integrating sedimentological and geochemical methods. This study highlights that the climatic and oceanic destabilization might have substantially impacted the marine biodiversity during the Middle Ordovician in South China. Three phases are identified based on lithological and geochemical variations. During Phase I across the Early–Middle Ordovician transition (Floian–Dapingian), the TOC and abundances of redox sensitive elements (RSE) are relatively depleted, suggesting a suboxic-oxic environment in the slope area of Yangtze Sea. The continental chemical weathering intensity transits from stable to unstable in Phase I indicated by CIA (chemical index of alteration) that gradually fluctuate to lower values, potentially caused by the secular cooling. The slowly ameliorating climate and redox conditions advanced the biodiversification across the Early–Middle Ordovician transition. During the Phase II in the Darriwilian, the continental chemical weathering intensity continues to decrease and the concentrations of RSE start to rise. The values of Mn(%)*Co(ppm) become consistently lower than 0.4, and the bio-limited elements such as P, Ba, and Ni are substantially enriched correspondingly. This phenomenon implicates that a secular cooling climate would have resulted in oceanic destabilization by improving upwelling of deeper anoxic/euxinic and eutrophic water into epicontinental sea, potentially causing a deceleration in the biodiversification during the Darriwilian in South China. The Phase III across the Middle–Late Ordovician transition, witnesses the continuous decrease of CIA values and highest abundances of TOC and RSE though some minor fluctuations, indicating a possibly even more drastic oceanic destabilization relative to Phase II. Deeper anoxic/euxinic water continuously intruded and shoaled into the shelf area during the Phase III due to the enhanced upwelling. Consequently, the habitat of marine organisms in shallow water was contracted, and becoming harsher. Additionally, bio-limited elements such as P were released from anoxic sediments and recycle into the seawater during the Middle Ordovician, boosting primary productivity level and may further deplete oxygen in seawater. This unstable oceanic state during the Middle Ordovician, particularly Darriwilian, represented by high nutrients content in epi-continental sea and expanding anoxic/euxinic water, could be attributable for the deceleration of biodiversification in South China and potentially the spatially variable paces of biodiversification in different paleo-continents during the main phase of the GOBE. • Sedimentology and geochemistry of Ordovician shales in South China spanning GOBE were reported. • Three phases of climatic and redox evolutions during Early-Middle Ordovician in South China. • The destabilization of ocean current and redox structure caused the contraction of habitat in South China. [ABSTRACT FROM AUTHOR]

This paper deals with a semilinear weighted parabolic problem in general bounded domains, subject to zero Dirichlet boundary conditions, where the weighted functions depend not only on space variable but also on time variable. Fujita exponents for blow-up and global existence of solutions are determined by using semigroup methods and the comparison principle, which are composed by the dimensions of the space domains and the eight exponents in nonlinear coupled sources and the space–time weighted functions. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with a reaction-diffusion system multi-coupled via inner sources and nonlinear boundary flux. The necessary and sufficient condition for the existence of non-simultaneous blow-up is proposed. Some regions of parameters are determined where both simultaneous and non-simultaneous blow-up can occur. In addition, sufficient conditions for non-simultaneous blow-up under any positive initial data are obtained. [Copyright &y& Elsevier]

• Tribo-corrosion of stainless steel in molten zinc alloy is studied. • Without wear, Fe2Al5Znx layer forms and protects steel from dramatic corrosion. • The synergy of corrosion and wear accounts for 90 % of material loss. • Corrosion induces brittle scale and embrittlement at subsurface, accelerating wear. • Wear promotes formation of less-protective FeZn 10 scale, accelerating corrosion. The failure of 316 stainless steel under tribo-corrosion in molten zinc alloy (Zn-0.2Al, wt%) at 460 °C was investigated and compared with corrosion or the sole wear. In the absence of wear, intact Fe 2 Al 5 Zn x layer forms and protects the steel from dramatic corrosion. Without liquid-metal corrosion, the steel suffers from plastic deformation on friction and slight adhesive wear. While for tribo-corrosion, the synergy of corrosion and wear accounts for 90 % of material loss. Firstly, corrosion generates a brittle scale and leads to embrittlement at subsurface, which accelerate wear. Secondly, wear promotes the formation of less-protective FeZn 10 scale, accelerating corrosion. [ABSTRACT FROM AUTHOR]

Background: To investigate changes in the corneal thickness profile in juvenile myopia after overnight wear of orthokeratology lenses (OK).Methods: A total of 53 juveniles (53 right eyes) successfully wore OK between January 2016 and July 2017 and they were reviewed one day, one week and one month after first wearing it. Epithelial and corneal data were obtained by optical coherence tomography (OCT). Changes in uncorrected visual acuity, refractive error, corneal refractive power, and epithelial and corneal thickness were analyzed before and after wear of OK.Results: The corneal epithelium was reshaped after 1 day of OK; the myopia degree was reduced, and uncorrected visual acuity reached 0 logMAR at 1 week. The central (2 mm) average epithelial thickness was 52.04 ± 2.35 μm, 49.25 ± 2.67 μm, 45.91 ± 2.80 μm, and 47.53 ± 3.44 μm before and after 1 day, 1 week, and 1 month of OK, respectively (t = 4.497, 9.741, and 7.340, respectively, P<0.001). The central epithelium was thinnest at 1 week, when the average thinning of 6.13 ± 1.67 μm accounted for approximately 11.78 % ± 3.21 % of the total epithelium thickness at baseline. The epithelial thickness of the reverse curve zone was 51.83 ± 2.49 μm, 57.62 ± 3.01 μm, 59.43 ± 3.19 μm, and 60.22 ± 2.75 μm before and after 1 day, 1 week, and 1 month of OK, respectively, showing a significant increase over time (t=-4.752, -6.208, and -6.848, respectively, P < 0.001).Conclusion: In the early stage of OK, the corneal epithelium was redistributed very quickly. The central epithelium became thin, while the epithelium of the reverse curve zone correspondingly thickened. Effectively reduced the refractive power of the cornea equivalent to the effect of adding a concave spectacle lens, which ensures uncorrected vision after removal of the lenses. [ABSTRACT FROM AUTHOR]

This paper deals with a reaction–diffusion equation with nonlocal inner source and nonlocal boundary flux. Besides the influence of exponents, we find out that the weighted functions and the measure of the domain could lead to the existence of global solutions for any initial data. Larger weighted functions require smaller initial data in guaranteeing the existence of global solutions to the problem. Blow-up rates are obtained under different dominations of nonlinearities in one dimensional space. The upper and lower bounds of blow-up time are determined for all spatial dimensions, respectively. Moreover, the solutions blow up only on the boundary when the nonlocal flux dominates the blow-up. [ABSTRACT FROM AUTHOR]

In order to reduce contamination levels from diverse sources, it is important to understand the factors affecting the natural ecosystems that are impacted by coastal and marine pollution. In this study, we used GIS and remote sensing techniques to investigate and evaluate the distribution of heavy metals (Fe, Mn, Zn, Cr, Pb, Co, and Cu) in surface sediments along Tamil Nadu's East Coast (from Besant Nagar to Sathurangapattinam). The CF and Igeo of metals indicate that sediments contain no evidence of Fe, Mn, or Zn metal pollution in the sediments, with only mild contamination from Co, Cu, and Pb. In contrast, the sediment samples were found to be significantly contaminated with Cr. Heavy metal contamination occurs in the following order, according to our research: Cr > Pb > Cu > Co > Mn > Zn > Fe. Except for sites 8, 10, 11, and 13, where PLI>1 implies that there is no pollution in this area, the PLI values show that most of the locations are contaminated. The ecological risk index (ERI) values for five metals in the study areas are as follows: Cr > Pb > Cu > Mn > Zn. The sediment samples fall into the low-risk and highly polluted to dangerous sediment categories for SPI, according to the Risk index (RI). Based on the Mean Effect Range-Median Quotient (M-ERM-Q), Cu, Pb, Zn, and Cr metals in the research region have a 9–21% probability of being harmful. Statistical approaches show that the majority of heavy metals in sediments are of natural origin. The spatial distribution of heavy metals in surface sediments provides the conceptual framework for practical strategies to protect coastal areas. Many shreds of evidence indicate that anthropogenic inputs from the surrounding land area are primarily responsible for the deposition of these heavy metals in the coastal zone. [Display omitted] [ABSTRACT FROM AUTHOR]

• The Milankovitch cycles are well preserved in the Dameigou Formation. • Coal seams derive organic matter from submerged and floating aquatic plants, as well as terrestrial higher plants. • Differences in the sources of organic matter in coal seams are driven by a combination of eccentricity, obliquity, and precession. Coal seams, as a terrestrial carbon sink, are not only important sedimentary and energy mineral resources but also excellent recorders of paleoclimate change. The study of coal-bearing strata is particularly significant in exploring the relationship between geological records and orbital forcing. However, the understanding of the relationship between coal seams of different sources of organic matter and astronomical cycles is incomplete. This study focuses on the Dameigou Formation, a typical Jurassic coal seam in the Qaidam Basin, Northwestern China. Organic petrology analysis, biomarker analysis, and whole-rock mineral analysis were combined to reconstruct the vegetation types and paleolake water level changes during coal seam deposition. In addition, using a time-series analysis method and high-precision gamma-scanning data from Well D1, we established a floating astronomical timescale and a time-depth model for cyclostratigraphical analysis. The results show that the Dameigou Formation, as coal-bearing strata, preserves well-developed Milankovitch cycles, and the climatic conditions and vegetation types during coal formation vary among different coal seams. Different patterns of variation in eccentricity, obliquity, and procession determine the thickness of the coal seam. This study is of great significance for understanding the astronomical factors that influenced climate evolution and coal deposition during the Middle Jurassic. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are considered to influence the bioavailability of heavy metals through direct adsorption, but this neglects the distribution of heavy metal chemical speciation indirectly influenced by MPs by altering geochemical properties. The present study aims to explore the link between the fractionation distribution of cadmium (Cd2+) and changes in geochemical properties in sediments induced by polyethylene terephthalate microplastics (PET-MPs). The PET-MPs reduced the acid-soluble fraction of Cd2+ in sediments and increased its organically bound fraction. In addition, the concentration of bioavailable Cd2+ in the sediment decreased by 4.09–25.96 % with increasing PET-MPs doses and aging. Whereas the thermal aging of PET-MPs led to a decrease in the molar ratio of oxygen-containing functional groups and the BET surface area, which is not favorable for improving the adsorption capacity of PET-MPs. On the other hand, the correlation analysis demonstrated the key role of PET-MPs in increasing the content of sediment organic matter and its humification level, which indirectly led to a decrease in Cd2+ bioavailability. The microbial analysis demonstrated that PET-MPs increase the relative abundances of Chloroflexi , hexokinase, and 6-phosphofructose kinase in sediments, thereby increasing the humification level of sediment organic matter. The present study provides a new perspective for understanding the environmental risks of MPs-altered heavy metals. [Display omitted] • MPs transformed Cd2+ into less bioavailable fractions in sediments. • Thermal aging enhanced MPs' inhibitory effect on Cd2+ bioavailability in sediments. • MPs reduced Cd2+ bioavailability by raising sediment OM and humification levels. • MPs-induced changes in sediment geochemical properties affect Cd2+ bioavailability. [ABSTRACT FROM AUTHOR]

• The Junggar Basin was in a dry environment during Jurassic. • The tectonic setting was continental island arc and active continental margin. • The source rocks are mainly felsic rocks in the upper crust. • Provenance of Jurassic sandstones in the southern margin of the Junggar Basin. Jurassic strata in the southern margin of the Junggar Basin are located in the piedmont zone of the North Tianshan Mountains in Xinjiang, China. Due to multiple tectonic movements, the basin has a complicated history of structural deformation. Accurate reconstructions of the tectonic setting, provenance attributes and paleoclimatic characteristics of the Jurassic strata in the area are vital to facilitate mineral resources prospecting (such as coal, oil, natural gas and uranium) in the basin. Here we used scanning electron microscopy, major and trace elements analyses (including rare earth elements; REE), clay mineralogy and heavy mineral composition in outcrop samples, to analyze the paleoclimate, tectonic setting, source rock properties and provenance characteristics in the southern margin of the Junggar Basin during the Jurassic period. The results are as follows: (1) according to major and trace elements and clay mineral assemblages, the degree of drought increased slightly from the Early Jurassic to the Late Jurassic concomitant increase. (2) Major and minor element discrimination and REE patterns indicate that the material was sourced from continental island arc and active continental margin environments, primarily from upper crustal felsic source rocks (mainly greywacke and arkose). (3) Heavy mineral and whole rock analyses show that the provenances of the Lower Jurassic sandstones were mainly from the primarily Zaire Mountain, North Tianshan Mt.-Middle Tianshan Mt., while the Upper Jurassic sediments were sourced from the primarily North Tianshan Mountain, Zaire Mountain, Middle Tianshan Mountain. [ABSTRACT FROM AUTHOR]

The Qaidam Basin in the northeastern part of the Tibetan Plateau preserves a continuous and thick Cenozoic sedimentary succession, which is of great significance to studying the aridification of inland Asia. Based on the normalized concentrations (element/Al) and chloride content records of the lacustrine sediments in deep drilling well SS9 in the western Qaidam Basin, the change in the aridity of inland Asia during the late Middle Eocene was investigated. The results show that the Al-normalized concentrations of Na and Cl, which are indicator elements of saline lake sediments, increased sharply at ~38 Ma. The peaks in the Ga/Al and chloride values indicate that the salinity of the lake was extremely high at ~38 Ma. Based on these results, the sudden decrease in the sedimentation rate, the chemical weathering index, the hematite content, and the (smectite + illite/smectite)/illite ratios, the Qaidam Basin experienced abrupt aridification during this period. The decrease in water vapor transport caused by the final retreat of the Paratethys Sea from the southern Tarim Basin may have been the main reason for the changes in the arid environment in the Qaidam Basin during the late Middle Eocene. Long-term global cooling and the uplift of the Altyn Tagh may have played a role in the background conditions. • Normalized concentrations were introduced as indicators of climatic evolution. • A continental record of abrupt aridification that occurred at ~38 Ma was provided. • Final retreat of the Paratethys Sea in the southern Tarim Basin was the main factor. [ABSTRACT FROM AUTHOR]