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Background: Peri‐implantitis and periodontitis have similar immunological bioprocesses and inflammatory phenotypes. In the inflammatory process, the adaptive immune cells can drive the development of disease. This research investigated the differences and diagnostic significance of peri‐implantitis and periodontitis in adaptive immune responses. Methods: We acquired four GEO datasets of gene expressions in surrounding tissues in healthy person, healthy implant, periodontitis, and peri‐implantitis patients. The structural characteristics and enrichment analyses of differential expression genes were examined. The adaptive immune landscapes in peri‐implantitis and periodontitis were then evaluated using single sample gene set enrichment analysis. The STRING database and Cytoscape were used to identify adaptive hub genes, and the ROC curve was used to verify them. Finally, qRT‐PCR method was used to verify the expression level of Hub gene in activated T cells on the titanium‐containing or titanium‐free culture plates. Results: At the transcriptome level, the data of healthy implant, peri‐implantitis and periodontitis were highly dissimilar. The peri‐implantitis and periodontitis both exhibited adaptive immune response. Except for the activated CD4+T cells, there was no significant difference in other adaptive immune cells between peri‐implantitis and periodontitis. In addition, correlation analysis showed that CD53, CYBB, and PLEK were significantly positively linked with activated CD4+T cells in the immune microenvironment of peri‐implantitis, making them effective biomarkers to differentiate it from periodontitis. Conclusions: Peri‐implantitis has a uniquely immunogenomic landscape that differs from periodontitis. This study provides new insights and ideas into the activated CD4+T cells and hub genes that underpin the immunological bioprocess of peri‐implantitis. [ABSTRACT FROM AUTHOR]

Northeast China (NEC) is the most prominent grain‐producing region in China. However, it is currently facing significant impacts from climate change. Since the climate‐related impacts on crop yield in this region are a major concern for society in the future, quantifying climate change impacts on crop yields in NEC is essential to ensure future food security. This study aimed to quantify the effects of future climate change on crop yields in NEC and explore adaptation strategies using the Crop Growth Model (PCSE) driven by downscaled CMIP6 climate projections under four Shared Socioeconomic Pathways (SSPs) scenarios during 2015–2100. Results showed that there could be average reductions in crop yields of 21.4% for maize and 4.2% for soybean by the year 2100 under SSP585 compared to the 2015 baseline. The increasing temperature was the dominant factor in reducing yields, although elevated CO2 and precipitation offered partial compensation. The optimized planting date brought noticeable benefits for rice and soybean but had limited effects on maize due to heat stress. Relocating rice expansion eastward and implementing earlier planting increased yields by up to 50% but adversely decreased soybean and maize due to competition. This study enriches our comprehension of climate change impacts on NEC agriculture, while also quantifying potential benefits and constraints of evaluated adaptations. The proposed adaptations may help mitigate projected yield declines in other key agricultural regions across the globe. Adjusting crop management practices to capitalize on changing climate factors shows promise as a strategy for sustaining production globally. Plain Language Summary: Northeast China (NEC) is essential for achieving food accessibility and food security in China, but its agricultural production is seriously threatened by climate change. This study investigated how climate change could impact maize, rice, and soybean crop yields in this region from 2015 to 2100, using the PCSE crop model and forcing from the international Coupled Model Intercomparison Project 6 (CMIP6) climate projections. Simulation results suggested rising temperatures would negatively affect crop yields, especially for maize. Increased carbon dioxide and rainfall partially offset these losses. By 2100, average declines were projected for maize (−21%) and soybeans (−4%), respectively. Altering planting dates to match crop needs was an effective adaptation to boost yields, with rice benefiting the most. Relocating rice production eastward and expanding its area substantially increased simulated rice yields (+62%) but decreased other crops due to competition (−32% maize, −28% soybeans). Even with adaptations, some areas still showed yield declines, indicating extra measures may be needed to maintain production. Overall, this study suggests significant risks to crop yields from climate change in Northeast China, with adaptations like optimized planting and strategic crop relocation able to mitigate some but not all of the projected impacts. Key Points: Rising temperatures negatively impacted simulated future crop yields, especially for maizeAdjusting planting dates boosted yields for rice and soybeans but had limited benefits for maizeRelocating and expanding the rice area increased yields substantially [ABSTRACT FROM AUTHOR]

This study develops an unstructured mesh generation tool for land surface modeling using a multi‐scale hexagon discrete mesh. The tool can automatically determine the required mesh resolution for different regions based on multi‐objective criteria such as elevation, slope, land cover, and land use. The refined unstructured meshes demonstrate significant enhancement in the representation of spatial heterogeneity. The tool is coupled with the Common Land Model (CoLM) to enable land surface simulations using unstructured meshes. Evaluations focused on runoff, river discharge, and inundation indicate improved model performance compared to traditional structured mesh‐based CoLM simulations under the same computational cost constraints. This tool provides new capabilities for more efficiently capturing localized land surface processes and extreme events. Plain Language Summary: The traditional square mesh cells used in land surface models (LSMs) have limitations in capturing the hydrological processes in regions with spatial solid heterogeneity, for example, mountains and forest‐grass transition zones. This study develops a new tool to generate unstructured mesh with flexible cell shapes and sizes. The tool can automatically adjust the mesh resolution based on the various land surface features. Thus, it can represent better spatial differences in elevation, vegetation, soil, etc. For example, it can use finer meshes for mountains and coarser meshes for desert areas. The new unstructured meshes are coupled with an existing LSM called Common Land Model. Model testing shows improved runoff, river discharge, and flooding simulation compared to traditional square mesh models under the same computation cost. Overall, the new unstructured mesh modeling approach enables more efficient and accurate simulation of localized land processes and extreme events, for example, droughts and floods. It has significance for disaster prevention and environmental studies. Key Points: An unstructured mesh generation tool for land surface models can automatically refine resolution based on multi‐objective landscape criteriaCoupling refined unstructured meshes with the Common Land Model (CoLM) model improves local hydrological simulation compared to traditional mesh‐based CoLMThe tool enables more efficient and accurate modeling of localized land surface processes and extreme events such as droughts and floods [ABSTRACT FROM AUTHOR]

The Jiaolai Basin, situated in the northern Sulu orogenic belt along East Aisa continental margin, preserves evidence of the extensional events in East Asia and the post‐orogenic evolution of the Sulu orogenic belt during the Cretaceous period. In this study, multiple provenance analyses were employed to reconstruct the source‐to‐sink system of the Laiyang Group within the Jiaolai Basin. These studies reveal a history of northward expansion dictated by two significant rift events. During the early Early Cretaceous period (ca. 135–121 Ma), the Zhucheng and Gaomi sags in southern region developed initially. Subsequently, in the late Early Cretaceous period (ca. 120–113 Ma), the Laiyang sag in northern region emerged. Furthermore, these sags were fed by independent source‐to‐sink systems in their early stages but eventually shared a similar source‐to‐sink system towards the end of the Laiyang Group deposition (ca. 113 Ma). The provenance analysis results indicate that ca. 121 Ma, ultrahigh‐pressure rocks in the northern segment of the Sulu orogenic belt experienced rapid exhumation, while those in the southern segment might have remained concealed until ca. 113 Ma. The two rift events in East Asia, coupled with the alteration in the direction and magnitude of extension documented in the Jiaolai Basin, suggests that trench retreat and the change in subduction direction from E–W to NW–SE of the Izanagi plate played a principal role in driving the extensional events in East Asia during the Early Cretaceous. Our findings imply that the change in Izanagi subduction direction may have occurred ca. 121 Ma.Model depicting the northward expansion evolution of the Jiaolai Basin in East Asia during the Early Cretaceous period. The left column illustrates the new stratigraphic framework as presented in this study. The grey arrows in the diagram indicate the primary provenance directions, with the size of the arrows representing the relative contribution of each source. [ABSTRACT FROM AUTHOR]

Variability in subsidence rates within Upper Cretaceous strata of the Western Interior Basin offers crucial insights into the response of surface sedimentation styles to Sevier‐to‐Laramide tectonics and related deep mantle processes. The formation mechanisms of the Late Cretaceous Western Interior Basin in North America have long been a subject of debate. A re‐evaluation of the basin's subsidence history reveals rapid subsidence pulses lasting ca. 2 Myr within longer‐term (average 5.7 Myr) progradational or aggradational clastic wedges. The timing of these wedges, especially the widespread marine flooding resulting from subsidence, is constrained through the calibration of ammonite zonation with absolute dates. Sevier wedges exhibit a different architecture compared to the Laramide wedges. The former recorded initial rapid and widespread marine transgressions followed by long‐term coastal progradation, whereas the latter developed by initial erosional and progradational growth followed by aggradation and long‐term coastal transgression. The Sevier clastic wedges, initially accumulated within a N‐S elongated, long‐wavelength tectonic subsidence zone close to the thrust belt, gradually migrated cratonward. Starting in the early Campanian (ca. 82 Ma), the Laramide Orogeny developed along a NW‐SE trend and then migrated northeastward, roughly consistent with coeval long‐wavelength frontal basin subsidence. The spatio‐temporal variations in long‐wavelength tectonic subsidence indicate a shift in the dynamic subsidence's migration direction from eastward to northeastward, driven by changes in Farallon subduction direction and mode. Our work shows how repeated subsidence behavior in the Sevier‐to‐Laramide transition records evolving architectural responses and the trajectory of coeval dynamic topography. Key Points: Shorter‐term rapid subsidence pulses discerned in longer‐term progradational or aggradational clastic wedges indicate the thrust eventsThe short‐term thrust events of Sevier‐to‐Laramide phase are recorded by different transgression‐regression geometric architecturesThe spatio‐temporal variations of long‐wavelength tectonic subsidence reveal migration of dynamic subsidence induced by plate subduction [ABSTRACT FROM AUTHOR]

Researchers and practitioners insist on equipping supply chains with the adaptive capability to return to a more desirable state after being disrupted. Various resilience capabilities have been emphasized in the literature; however, limited research has linked them to resilience phases and cultural value orientations. Moreover, preparedness and adaption phases have hardly been studied. To address these gaps, we adopted middle‐range theory to investigate agri‐food supply chain (AFSC) resilience to the COVID‐19 crisis in a cross‐country setting. Data were collected from interviews with AFSC practitioners from China and Spain, followed by thematic and comparative analyses. The results indicate that frequently discussed resilience capabilities, such as collaboration, redundancy, flexibility, leadership, and innovation, were implemented across the preparedness, response and recovery, and adaption phases; however, successful AFSC recovery also depends on each country's cultural value orientations. A hierarchical cultural orientation generates sense‐making and collectiveness and further leads to synergy across all AFSC stakeholders, thereby contributing to AFSC response and recovery. Under an egalitarianism cultural orientation that places self‐interest ahead of group goals, organizations are encouraged to make decisions based on their own situational understanding, which contributes to their response and recovery. This study also provides theoretical contributions and managerial and policy implications. [ABSTRACT FROM AUTHOR]

Surface flux estimation is essential to land surface modeling in earth system models. In practice, parameterizations of surface turbulent fluxes are almost all based on the similarity theory. That is, the grid or subgrid mean surface‐layer flow is assumed at equilibrium with the underlying earth surface, and therefore some empirical relations can be used to estimate surface fluxes. In this paper, scale‐dependent estimability of turbulent flux in the unstable surface layer is systematically investigated based on high‐resolution large‐eddy simulation data over a flat and homogeneous domain, representing a typical land surface modeling grid. It is found that turbulent flow in the unstable surface layer inherently fluctuates over a wide range of scales. This kind of fluctuation affects the steady‐state relations between mean atmospheric quantities and underlying earth surface, and hence affects the estimability of surface fluxes. Sensitivity tests show that the relative root mean square error of the estimated surface friction velocity for a subdomain generally increases as the subdomain becomes smaller. The error can be as high as 35% as the subdomain size decreases to the order of the surface layer height. To achieve an error of 10% for all cases, the subdomain size should be at least on the order of the boundary layer height. These findings imply that estimability‐based strategies may be needed for representing subgrid heterogeneity for surface flux estimation in land surface modeling. Plain Language Summary: Flux‐related land surface modeling involves much the representation of subgrid land surface. Land Cover Type (LCT) and Plant Functional Type (PFT) are the two main subgrid land surface representation approaches applied by modern land surface models. The two approaches both use some sort of subgrid "tiling" system. Tiles are defined as spatially aggregation of the area belonging to a land surface type (or category). Applying a novel analysis approach developed in this study and based on high‐resolution large‐eddy simulation data over an ideal domain, representing a typical land surface modeling grid, we find that the multiscale fluctuation of turbulent flow in the unstable surface layer makes the estimability of surface fluxes scale dependent. A subdomain with larger size or sparser distribution tends to achieve higher estimability. It is indicated that to reduce the estimation error to 10% for land surface modeling, the subgrid size should be at least on the order of the boundary layer height. This implies that aggregating small patches into a larger subgrid tile may introduce errors and traditional strategies, such as the LCT and PFT mosaic approaches, are probably not applicable to surface flux estimation. Estimability‐based strategies may need to be developed. Key Points: Multiscale turbulent fluctuations affect local equilibrium in the unstable surface layerFluctuation‐related nonequilibrium in the surface layer yields scale‐dependent surface turbulent fluxUncertainty of surface flux is quantified based on equilibrium‐based classical theory [ABSTRACT FROM AUTHOR]

Non‐invasive and rapid imaging technique at subcellular resolution is significantly important for multiple biological applications such as cell fate study. Label‐free refractive‐index (RI)‐based 3D tomographic imaging constitutes an excellent candidate for 3D imaging of cellular structures, but its full potential in long‐term spatiotemporal cell fate observation is locked due to the lack of an efficient integrated system. Here, a long‐term 3D RI imaging system incorporating a cutting‐edge white light diffraction phase microscopy module with spatiotemporal stability, and an acoustofluidic device to roll and culture single cells in a customized live cell culture chamber is reported. Using this system, 3D RI imaging experiments are conducted for 250 cells and demonstrate efficient cell identification with high accuracy. Importantly, long‐term and frequency‐on‐demand 3D RI imaging of K562 and MCF‐7 cancer cells reveal different characteristics during normal cell growth, drug‐induced cell apoptosis, and necrosis of drug‐treated cells. Overall, it is believed that the proposed 3D tomographic imaging technique opens up a new avenue for visualizing intracellular structures and will find many applications such as disease diagnosis and nanomedicine. [ABSTRACT FROM AUTHOR]

Chemoselective terpolymerization can produce polymer materials with diverse compositions and sequential structures, and thus have attracted considerable attention in the field of polymer synthesis. However, the intrinsic complexity of three‐component system also brings great chanllenge, in regard to the reactivity and selectivity of different monomers. Herein, we report the terpolymerization of CO2/epoxide/anhydride by a binary organocatalytic C3N3‐Py‐P3/TEB (triethylborane) system. Both the activity and chemoselectivity were highly dependent upon the molar ratio of C3N3‐Py‐P3 to TEB, and sequence‐controlled poly(ester‐carbonate) copolymers were readily synthesized through one‐pot/one‐step methodology by tuning the stoichiometric ratio of phosphazene/TEB. In particular, C3N3‐Py‐P3/TEB with a molar ratio of 1/0.5 exhibited an unprecedentedly high chemoselectivity for ring‐opening alternating copolymerization (ROAC) of cyclohexene oxide (CHO) and phthalic anhydride (PA) first and then ROAC of CO2/CHO. Thus, well‐defined triblock polycarbonate‐b‐polyester‐b‐polycarbonate copolymers can be produced from the mixture of CO2, CHO and PA using a bifunctional initiator. With C3N3‐Py‐P3/TEB=1/1, tapered copolymers were obtained, while random copolymers with high content of polycarbonate (PC) were synthesized with further increasing the amount of TEB. The mechanism of the unexpected chemoselectivity was further investigated by DFT calculations. [ABSTRACT FROM AUTHOR]

We propose a surface flux estimation formula to account for large eddy effects by keeping the boundary layer depth the only added parameter. We develop a novel way to evaluate the estimation formula by using a set of independent large eddy simulations, in which the vertical extents of largest eddies affecting surface layer are confined in a wide range of depths. It is found that these confined vertical extents hold a significant linear relationship (with slope of ∼1) with the inversely estimated vertical extents of affecting large eddies. This close relationship between the two vertical extents verifies the hypothesis that the boundary layer depth is linearly relevant for accounting for large eddy effects. Moreover, the two vertical extents are found to be comparable in value. This implies that the estimation formula we propose here is likely to be valid and applicable to unstable boundary layer in general. Plain Language Summary: Surface flux estimation is crucial to land surface modeling and numerical weather prediction and climate modeling. We recently revealed that large eddies can greatly affect surface fluxes under unstable conditions. But the large eddy effects are usually neglected in traditional surface flux estimation schemes. Here, we propose a surface flux estimation scheme to account for large eddy effects for land surface modeling. We develop a novel way to evaluate the estimation scheme by using a set of independent large eddy simulations, in which the vertical extents of largest eddies affecting surface layer are confined in a wide range of depths. It is found that these confined vertical extents hold a significant linear relationship (with slope of ∼1) with the inversely estimated vertical extents of large eddies that affect the surface layer. This close relationship between the two vertical extents verifies the hypothesis that the boundary layer depth is linearly relevant to account for large eddy effects. Moreover, the two vertical extents are found to be comparable in value. This implies that the estimation formula we propose here is likely to be valid and applicable to land surface modeling in general. Key Points: Surface momentum flux estimation formula considering large eddy effects in unstable boundary layer is further simplifiedThe simplified surface momentum flux estimation formula reflects the varying vertical extent of largest eddiesThese results are obtained by confining the vertical extents of largest eddies in a wide range of depths in large eddy simulations [ABSTRACT FROM AUTHOR]

Background: Central precocious puberty (CPP) is a precocious puberty due to premature activation of the hypothalamic–pituitary‐gonadal axis (HPG). MKRN3 defects are well‐known causes of CPP, while DLK1 mutations were recently identified in a few patients with CPP. Methods: The study was approved by the Institutional Review and the scientific committee of the hospital. The clinical data were collected. Whole‐exome sequencing (WES) was performed to detect causative variants. Key words 'DLK1', 'MKRN3', and "central precocious puberty" were used for literature search in PubMed, Google Scholar, HGMD, and OMIM databases. Results: The patient, a male, whose puberty began before age nine, had significant metabolic abnormalities including overweight, hyperlipidemia, and hyperuricemia. WES detected a recurrent frame‐shift mutation, NM_003836.5:c.479delC(p.P160fs*50) in DLK1 in the patient and his father. Conclusion: The familial DLK1‐CPP was identified in China for the first time, which supported that short stature is predicted in patients with CPP without GnRHa treatment. Therefore, we recommend that children with DLK1‐CPP should be treated as early as possible to improve adult height. The patient in this study had persistent hyperuricemia, further suggests that this antiadipogenic factor represents a link between reproduction and metabolism. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A series of titanium amido complexes (1‐Ti(NMe2)2 to 4‐Ti(NMe2)2) bearing NNO‐tridentate ligands was synthesized from the reactions of phenoxy‐imine‐amine ligands with one equivalent of Ti(NMe2)4. Subsequently, titanium dichloride complexes (1‐TiCl2 to 4‐TiCl2) were prepared by treatment of titanium amido complexes with excess Me3SiCl in toluene. All metal complexes were characterized by 1H and 13C NMR spectroscopy, and the molecular structures of complexes of 2‐Ti(NMe2)2, 2‐TiCl2, and 4‐TiCl2 in the solid state were determined by single‐crystal X‐ray diffraction. Upon activation with MAO, titanium dichloride complexes as single‐site catalysts were extremely active toward ethylene homopolymerization with great control on molecular weight and distribution. In particular, 3‐TiCl2/MAO exhibited an activity as high as 1.35 × 108 g(PE)·mol−1(Ti)·h−1 at 70°C and produced polyethylene with high molecular weight (41.7 × 104 g∙mol−1) and very narrow distribution (Đ = 1.23). In the presence of 1‐octene as comonomer, linear low‐density polyethylenes (LLDPEs) with ultrahigh molecular weights (Mw = 136—326 × 104 g∙mol−1) and narrow distributions (Đ = 1.20—1.50) were successfully synthesized. [ABSTRACT FROM AUTHOR]

The planetary boundary layer height (PBLH) is a fundamental variable of the planetary boundary layer (PBL). The effect of surface heterogeneity is challenging in the PBL parameterization for numerical weather and climate models. Here we use large eddy simulation data to investigate the impact of surface heating heterogeneity on the PBLH spatial variations and mean values over a domain of typical mesoscale model grid size. It is found that this impact depends on background wind condition. Variance decomposition and Fourier spectra both reveal that for the fully developed sheared convective PBL, surface heterogeneity contributes little to the spatial variation of PBLH, except for the case with heterogeneity scale of 14.4 km. This suggests that surface heterogeneity with length scales less than ∼10 km, which is typical for mesoscale modeling, does not induce significant subgrid spatial variation of PBLH. The domain‐averaged PBLH is found to generally increase as surface heterogeneity scale decreases, until reaching the scale on the order of PBLH. The findings can be used to inform the parameterization development of PBL processes over heterogeneous surface. Key Points: Surface heterogeneity with scales less than ∼10 km does not induce significant spatial variation of planetary boundary layer (PBL) height for sheared convective PBLThe highest domain‐averaged PBL height occurs with surface heterogeneity scales on the order of PBL heightImpact of surface heterogeneity depends on background wind condition [ABSTRACT FROM AUTHOR]

Objectives: To explore the role of DNA methyltransferase 1 (DNMT1) in the development of auditory system using zebrafish as experimental model. Methods: Morpholino oligonucleotide was used to induce Dnmt1 deficiency. RNA sequencing, in situ hybridization (ISH), whole genomic bisulfide sequencing (WGBS) and immunostaining were used to investigate the morphologic alterations and mechanisms. Results: We found that downregulation of Dnmt1 induced decreased number of neuromasts and repressed cell proliferation of primordium in the developing posterior lateral line system of zebrafish. The ISH data uncovered that Fgf signalling pathway was inhibited and the expression of chemokine members cxcr4b, cxcr7b and cxcl12a were interfered, while lef1 expression was increased after inhibiting Dnmt1. Additionally, Dnmt1 downregulation led to malformed otoliths and deformed semicircular canals, and hair cell differentiation in utricle and saccule was inhibited severely. The in situ staining of otic placode markers pax2/5 and fgf 3/8/10 was decreased when Dnmt1 downregulated. The WGBS analysis demonstrated that the global methylation status was markedly downregulated, and cell cycle genes were among those most differently expressed between Dnmt1 morphants and the controls. Further ISH analysis confirmed the findings by RNA‐seq and WGBS assay that cdkn1a and tp53 were both upregulated after knockdown of Dnmt1. Conclusion: Our results revealed that Dnmt1 is essential for the development of zebrafish auditory organ through regulating cell cycle genes together with Wnt and Fgf signalling pathways. [ABSTRACT FROM AUTHOR]

Arguments for recognizing autogenic vs. allogenic signals in the stratigraphic record are still far from settled, as is the decoding of unsteady allogenic responses to climate vs. tectonic forcing. We offer the case of late Mesozoic Xuanhua basin in the western Yanshan fold‐and‐thrust belt of North China to make these points. The study area is an intramontane basin that has allowed detailed structural, sedimentological, and provenance analyses in a kilometre‐thick succession (the Tuchengzi Formation) of alluvial fan, fluvial, lake‐delta and lacustrine deposits. Extensive geological mapping provided confidence of near‐basinwide later correlation of strata, revealing two large‐scale upward‐coarsening (CU) successions each 80–240 m thick, with prominent vertical changes from lacustrine through deltaic and fluvial to alluvial fan deposits. Two intervals of thrust‐related growth strata identified in the Tuchengzi Fm suggest that the CU successions were the signals of tectonic uplift and accommodation change related to Likouquan and the Mapu thrusting. In the lower CU succession, there is a stacking (30+) of small‐scale (3–16 m thick) upward‐fining cyclothems that are argued to have been generated by alternating wet‐dry climate cycles. The wet half‐cycle is argued to have initiated with high sediment and water discharge of flood‐generated mass flows into the lake and ended with accumulation of lacustrine mudstones as lake level rose. The lake deposits include the maximum flooding during the wet half‐cycle. The dry half‐cycle was characterized by continued lacustrine deposits, but increased evidence of subaerial exposure (rooting, paleosols, and mudcracks) argued to result from falling of the lake level under dry conditions. [ABSTRACT FROM AUTHOR]

Organophosphazenes combined with triethylborane (TEB) were selected as binary organocatalyts for the copolymerization of CO2 and epoxides. Both the activity and selectivity were highly dependent on the nature of phosphazenes. 2,4,6‐Tris[tri(1‐pyrrolidinyl)‐iminophosphorane]‐1,3,5‐triazine (C3N3‐Py‐P3) with a relatively low basicity (pKa=26.5 in CD3CN) and a bulky molecular size (φ=1.3 nm) exhibited an unprecedented efficiency (TON up to 12240) and selectivity (>99 % polymer selectivity and >99 % carbonate linkages) toward copolymerization of CO2 and cyclohexene oxide (CHO), and produced CO2‐based polycarbonates (CO2‐PCs) with high molar masses (Mn up to 275.5 kDa) at 1 MPa of CO2 and 80 °C. Surprisingly, this binary catalytic system achieved efficient CO2/CHO copolymerization with TOF up to 95 h−1 at 1 atm pressure and room temperature. [ABSTRACT FROM AUTHOR]

Multivalent metal‐ion hybrid capacitors (MMHCs) have drawn much attention in recent years because of their advantages of high energy density (similar to metal‐ion batteries) as well as high power density, high rate capability, and ultra‐long cycle life. However, there are still challenges in developing high‐performance MMHCs, e. g. high‐capacity capacitive materials are particularly needed to be developed to match high‐energy battery‐type electrodes. Therefore, designing novel electrode materials and exploring suitable electrolytes are of particular importance. Herein, we focus on the recent progress of MMHCs in relation to their cathode/anode materials, electrolytes, electrochemical properties, and energy storage mechanisms. Additionally, the current challenges or bottlenecks and future research trends regarding MMHCs are summarized. This review provides a comprehensive understanding of the research framework of MMHCs and will be beneficial in the development of high‐performance MMHC devices. [ABSTRACT FROM AUTHOR]

The configuration and kinematics of fold‐thrust belts are essential for clarifying the plate boundary conditions through which ancient orogenic belts evolved. Temporal and spatial variations in extension versus contraction within convergent plate margins are related to changes in plate kinematics and subduction geometry. The Yanshan Mountains, located along the northeastern margin of the North China Craton and bounded by the Central Asian Orogenic Belt to the north and the Pacific subduction zone to the east, underwent multiple phases of intra‐continental deformation during the Mesozoic. The issue of whether early Mesozoic deformation was extensional or contractional has remained controversial. New regional structural mapping and detailed sedimentological investigations, coupled with age constraints provided by zircon U‐Pb geochronology, provide sufficient temporal and spatial resolution to show that shortening and thrust‐top basin systems dominated during the early Mesozoic. Our results show that the Dengzhangzi Basin within the Lingyuan fold‐thrust belt developed during the construction of a major Late Triassic Chapeng antiformal‐stack duplex system, with episodic, east‐vergent forward‐breaking thrusts and subsequent 'beheading' by out‐of‐sequence, top‐to‐east thrusting in the latest Triassic or earliest Jurassic. The neighbouring Guojiadian Basin in the east was generated during top‐to‐SSE sinistral transpression along the Niuyingzi thrust system in the Middle to earliest Late Jurassic. These results support a new model of early craton decratonization involving (a) thrusting along the northern margin of the North China Craton and (b) transpressional deformation in the east driven by the Central Asian Ocean collision and flat‐slab subduction of the Palaeo‐Pacific Plate beneath the East Asian continental margin. Our findings suggest that large‐scale shortening and crustal/lithospheric thickening, triggered by flat‐slab subduction in the North China Craton, were fundamental components of craton decratonization. Subsequent slab roll‐back during the Cretaceous led to lithospheric thinning and crustal extension in the North China Craton. [ABSTRACT FROM AUTHOR]

The kinematics of plate tectonics, deformation, and dynamic topography are strong indicators of coupling between plates and the mantle. East Asia is characterized by the presence of an unusually large horizontal slab that lies within the mantle transition zone. How this feature evolved and is linked to plate tectonics, deformation, and topography is poorly understood. Here, we show four‐dimensional geodynamic modeling results constrained by a new deforming plate reconstruction that fits mantle architecture inferred from seismic tomography. We find that the subducted western Pacific slab was progressively torn by the Philippine Sea plate rotating clockwise during the Miocene and that northwestward mantle flow contributed to shaping the horizontal slab during subduction, leading to dynamic subsidence along the East Asia margin. The rather subdued change in dynamic topography, predicted from those models that fit the horizontal slab in the mantle, is consistent with the variation in residual topography, recorded in the stratigraphy, within only about ±200 m over the last 50 Myr during a period of no large marine inundation or retreat. The tectonics and topography of East Asia strongly contrast with those of Southeast Asia and are reflective of slabs ephemerally stagnating in the mantle below East Asia while avalanching into the lower mantle below Southeast Asia. Key Points: Trench‐trench‐trench triple junction shift‐induced tearing of the Pacific slab and contributed to shaping the horizontal slabThe dynamic topography fits with variation in residual subsidence by approximately ±200 m over the last 50 MyrThe subdued topography of East Asia was a response to stagnant slabs in the mantle [ABSTRACT FROM AUTHOR]

A well‐constrained plate deformation model may lead to an improved understanding of sedimentary basin formation and the connection between subduction history and over‐riding plate deformation. Building quantitative models of basin kinematics and deformation remains challenging often due to the lack of comprehensive constraints. The Bohai Bay Basin (BBB) is an important manifestation of the destruction of the North China Craton, and records the plate kinematic history of East Asia during the Cenozoic. Although a number of interpretations of the formation of the BBB have been proposed, few quantitative basin reconstruction models have been built to test and refine previous ideas. Here, we developed a quantitative deformation reconstruction of the BBB constrained with balanced cross‐sections and structural, stratigraphic and depositional age data. Our reconstruction suggests that the basin formation process was composed of three main stages: Paleocene‐early Eocene (65–42 Ma) extension initiation, middle Eocene‐early Oligocene (42–32.8 Ma) extension climax and post‐Oligocene (32.8–0 Ma) post‐extensional subsidence. The deformation of the BBB is spatially heterogeneous, and its velocity directions rotated clockwise during the basin formation process. The reconstruction supports the interpretation that the BBB formed via strike‐slip faulting and orthogonal extension and that the basin is classified as a composite extensional‐transtensional basin. We argue that the clockwise rotation of the basin velocity field was driven by the counter‐clockwise rotation in the direction of Pacific Plate subduction. The kinematics of the BBB imply that the Pacific Plate may have been sufficiently coupled to the over‐riding East Asian Plate during the critical period of Pacific Plate reorganization. The new reconstruction provides a quantitative basis for studies of deformation processes not only in the vicinity of the BBB, but also more broadly throughout East Asia. [ABSTRACT FROM AUTHOR]

Tectonics in North China and adjacent areas were dominated by the Pacific Plate subduction since the Jurassic. Although the extension‐dominated tectonics in North China since the Early Cretaceous can be well explained by the Pacific Plate subduction, it is still not well understood why North China and adjacent areas underwent intense compression (Yanshanian orogeny) during the Late Jurassic and why these regions rapidly switched to extension‐dominated tectonics during the Early Cretaceous. Plate reconstructions suggest that East Asia was moving rapidly in the direction opposite the trench during the Jurassic when North China was undergoing strong compressional deformation. This relationship between back‐arc deformation and overriding plate's motion seems to contradict previous compilations and geodynamic models. We suggest that large‐scale mantle convection and exotic terrane accretions along the East Asian margin have jointly contributed to the Yanshanian orogeny across North China during the Jurassic. We verify this hypothesis with numerical geodynamic models. Our numerical experiments also suggest that large‐scale downwelling mantle flow beneath Asia has promoted continued subduction beneath the Asian margin despite the subduction was often punctuated by collisional and accretionary events. Key Points: North China and adjacent areas suffered strong compressional tectonics when they were drifting in the direction opposite the trenchExotic terrane accretion and large‐scale mantle convection jointly contributed to the strong compression in North ChinaLarge‐scale mantle convection promoted long‐term, continued subduction beneath the Asian margin [ABSTRACT FROM AUTHOR]

Soil thermal conductivity (STC) is an important physical parameter in modeling land surface processes. Previous studies on evaluations of STC schemes are mostly based on direct measurements of local conditions, and their recommendations cannot be used as a reference in selecting STC schemes for land modeling use. In this work, seven typical STC schemes are incorporated into the Common Land Model to evaluate their applications in land surface modeling. Statistical analyses show that the Johansen (1975) scheme and its three derivatives, Côté and Konrad (2005, https://doi.org/10.1139/t04‐106), Balland and Arp (2005, https://doi.org/10.1139/s05‐007), and Lu et al. (2007, https://doi.org/10.2136/sssaj2006.0041), are significantly superior to the other schemes with respect to both STC estimations and their applications in modeling soil temperature and the partitioning of surface available energy in the Common Land Model. The Balland and Arp (2005, https://doi.org/10.1139/s05‐007) scheme ranks at the top among the selected schemes. Uncertainty analyses based on single‐point and global simulations both show that the differences in STC estimations can induce significant differences in simulated soil temperature in arid/semiarid and seasonally frozen regions, especially at deep layers. The hydrology‐related variables are slightly affected by STC variations, but slight changes in these variables can induce notable changes in soil temperature by altering soil thermal properties. These results emphasize the important role of STC in modeling soil thermodynamics and suggest the necessity of further developing STC schemes based on land modeling applications. According to the evaluation analyses, we recommend the Balland and Arp (2005, https://doi.org/10.1139/s05‐007) scheme as a more suitable selection for use in land surface models. Plain Language Summary: Soil thermal conductivity (STC) is essential for simulating soil temperature and heat flux in land surface models. Previous studies have proposed quite a few parameterization schemes to estimate STC. Although many works have tried to determine which scheme performed best, most of them were based on direct measurements from specific experimental conditions or local soil samples, and few studies have considered the performances of STC schemes in land surface modeling. Here, we present an evaluation of seven typical STC schemes based on their land modeling applications. The results show that four of the schemes, the Johansen (1975) scheme, Côté and Konrad (2005, https://doi.org/10.1139/t04‐106) scheme, Balland and Arp (2005, https://doi.org/10.1139/s05‐007) scheme, and Lu et al. (2007, https://doi.org/10.2136/sssaj2006.0041) scheme, perform comparatively better than the other schemes and that the Balland and Arp (2005, https://doi.org/10.1139/s05‐007) scheme ranks at the top. Uncertainty analyses demonstrate that soil thermodynamics are strongly sensitive to STC estimates, especially in dry and partly frozen regions. This relationship highlights the important role of STC in modeling land surface processes. Currently, we recommend the Balland and Arp (2005, https://doi.org/10.1139/s05‐007) scheme as a good selection for use in land surface models. Key Points: Seven typical soil thermal conductivity schemes are evaluated by incorporation into the Common Land ModelThe Johansen (1975) scheme and its three derivatives perform better than the others, with the Balland and Arp (2005, https://doi.org/10.1139/s05‐007) scheme ranking at the topUncertainty analyses show strong effects of soil thermal conductivity on soil thermodynamics in arid/semiarid regions and seasonally frozen regions [ABSTRACT FROM AUTHOR]

Modeling land surface processes requires complete and reliable soil property information to understand soil hydraulic and heat dynamics and related processes, but currently, there is no data set of soil hydraulic and thermal parameters that can meet this demand for global use. In this study, we propose a fitting approach to obtain the optimal soil water retention parameters from ensemble pedotransfer functions (PTFs), which are evaluated using the global coverage National Cooperative Soil Survey Characterization Database and show better performance for global applications than our original ensemble estimations (median values of PTFs) as done in Dai et al. (2013, https://doi.org/10.1175/JHM‐D‐12‐0149.1). Soil hydraulic conductivities are still estimated as the median values of multiple PTFs, and the results are shown to perform comparably to the estimates from the existing precision‐advanced models. Soil thermal properties are estimated following the schemes identified by Dai et al. (2019a, http://arxiv.org/abs/1908.04579), which evaluated several highly recommended schemes based on their land modeling applications. Using these approaches, we develop two global high‐resolution data sets of soil hydraulic and thermal parameters based on Global Soil Dataset for Earth System Models (GSDE) and SoilGrids soil composition databases. The delivered variables include six basic soil properties, four soil hydraulic parameters in the Campbell (1974, https://doi.org/10.1097/00010694‐197406000‐00001) model, five soil hydraulic parameters in the van Genuchten (1980, https://doi.org/10.2136/sssaj1980.03615995004400050002x) model, and four soil thermal properties. The delivered data sets are available at a 30″ × 30″ geographical spatial resolution and provide four sets of vertical profiles following the resolutions of SoilGrids, Noah‐Land Surface Models (LSM), Joint UK Land Environment Simulator (JULES), and Common Land Model/Community Land Model (CoLM/CLM). The data sets can be used in both regional and global applications. Plain Language Summary: The parameters of soil hydraulic and thermal properties are essential to the modeling of land surface processes, but no data set is currently available for global use. Using some newly proposed and existing widely used schemes, we developed two global high‐resolution data sets of soil hydraulic and thermal parameters based on two commonly used soil composition databases (Global Soil Dataset for Earth System Models [GSDE] and SoilGrids). The delivered variables include multiple basic soil properties and all the required parameters for solving soil hydraulic and heat dynamics and related processes. The data sets follow the vertical profiles of SoilGrids data set and four land surface models (i.e., Noah‐Land Surface Models [LSM], Joint UK Land Environment Simulator [JULES], Common Land Model [CoLM], and Community Land Model [CLM]). The data sets can be used in both regional and global applications. Key Points: A new fitting approach is proposed to obtain the optimal soil water retention parameters from ensemble pedotransfer functionsThe adopted approaches for soil hydraulic parameter estimations are evaluated to be superior or comparative to other approachesGlobal maps of soil hydraulic and thermal parameters for use in land models are produced based on two soil composition data sets [ABSTRACT FROM AUTHOR]

The Yanshan fold‐thrust belt is a significant intraplate deformation belt along the northern margin of North China Craton and records multiple phases of deformation during the Mesozoic. However, the specific tectonic evolution of the Yanshan belt during the Mesozoic has long been debated. In particular, many arguments exit regarding whether a contractional or extensional context dominated the Yanshan belt in the Late Jurassic‐Early Cretaceous. One reason for this argument is the poor understanding of the tectono‐sedimentary relationship preserved in the sedimentary records. A lack of evidence of syntectonic sediments makes it more difficult to reconstruct this relationship. The Chicheng basin in the western Yanshan belt contains complete Upper Jurassic‐Lower Cretaceous succession and is bounded by marginal faults. New regional geological mapping, detailed sedimentary facies analysis, and recognition of two growth strata packages help reconstruct the tectono‐sedimentary relationship in the Chicheng basin. Additionally, zircon U‐Pb dating provides constraints on the timing of the deformation. Our results suggest that the dynamic sediment dispersal system in the Chicheng basin during the Late Jurassic‐Early Cretaceous were controlled by two phases of thrusting, including the activities of the Shangyi‐Pingquan fault during 162–147 Ma, and the Fengning‐Longhua fault during 140–135 Ma. Therefore, we propose that the western Yanshan belt was in a contractional context during the Late Jurassic‐Early Cretaceous. Our findings indicate that the tectonic setting of the Yanshan belt experienced a prominent transition from E‐W trending structures to NE‐SW trending structures and that this transition was probably related to subduction of the Paleo‐Pacific plate beneath the East Asian continent. Key Points: Two packages of growth strata associated with fault‐related folding were recognized in the Late Jurassic‐Early Cretaceous Chicheng basinSedimentary and provenance analyses reveal the three‐stage evolution of the Chicheng basin during the Late Jurassic‐Early CretaceousThe Yanshan belt was under NW‐SE compression by the subduction of the Paleo‐Pacific plate during the Late Jurassic‐Early Cretaceous [ABSTRACT FROM AUTHOR]

Global deep‐time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic–Cenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 × 106 km2 in the Late Jurassic (~160–155 Ma), driven by a vast network of rift systems. After a mid‐Cretaceous drop in deformation, it reaches a high of 48 x 106 km2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate‐mantle system. Key Points: We present a plate motion model including distributed deformation from the Triassic to the presentThe model includes most major rifts and orogens formed since the breakup of the supercontinent PangeaOur optimized mantle reference frame minimizes trench migration and net rotation [ABSTRACT FROM AUTHOR]

The present‐day architecture of subducted slabs in the mantle as inferred from seismic tomography is a record of plate tectonics through geological time. The unusually large slab that lies nearly horizontally above the 660‐km mantle discontinuity beneath East Asia is presumably from subduction of the Pacific plate. Numerical models have been used to explore the mechanical and geophysical factors that contribute to slab stagnation, but the evolution of this horizontal structure is not fully understood because of uncertainties in the plate‐tectonic history and mantle heterogeneity. Here we show that forward mantle‐flow models constrained by updated tectonic reconstructions can essentially fit major features in the seismic tomography beneath East Asia. Specifically, significant tearing propagated through the subducted western Pacific slab as the Philippine Sea plate rotated clockwise during the Miocene, leading to internal slab segmentation. We believe this tearing associated with Philippine Sea plate rotation also affects the horizontal configuration of slabs. Plain Language Summary: The present‐day architecture of subducted slabs in the mantle as inferred from seismic tomography is a record of plate tectonics through geological time. The structure of the mantle below East Asia is dominated by a flat slab which extends more than 2,300 km laterally inland (Liu, Zhao, et al., 2017, https://doi.org/10.1016/j.epsl.2017.02.024, https://doi.org/10.1016/j.earscirev.2017.10.012). The origin of this unusual but globally significant flat‐slab structure has been the subject of considerable discussion in the literature through a series of global and high‐resolution seismic inversions. Is this phenomenon caused by unusual regional processes, or have some global mantle processes been overlooked? Here we reproduce this highly unusual flat‐slab structure with a four‐dimensional computational model and argue that this slab is a natural consequence of the plate‐tectonic evolution of East Asia. We provide a solution to this problem through a combination of new plate‐tectonic reconstructions and a 4‐D computational approach that assimilates plate tectonics with the physics of mantle convection. This paper reports a new paradigm for the East Asia margin, where the regional tectonics are characterized by the development of a typical trench‐trench‐trench triple junction, and resultant significant tearing that propagated through the subducted western Pacific slab as the Philippine Sea plate rotated clockwise during the Miocene. Key Points: A new plate reconstruction of East Asia fully depicts the NE migration of a trench‐trench‐trench triple junction since 30 MaThis triple‐junction migration led to the overlapping, tearing, and detachment of subducted slabs in East AsiaLarge–scale ambient mantle flow should have contributed to the formation of the horizontal slab [ABSTRACT FROM AUTHOR]

The article focuses on the importance of the plate tectonic reconstruction in collecting geological data.

Abstract: Porous organic polymers (POPs) have been considered as prominent adsorbents for volatile iodine. So far, both crystalline and amorphous POPs have accomplished excellent iodine capture capability. Considering the difficulty and challenges in preparing perfect crystalline POPs, more explorations into developing versatile amorphous POPs are needed. Herein, amorphous POPs based on the Schiff‐base reaction were designed and synthesized for volatile iodine removal. Four amorphous POPs products named as NDB‐H, NDB‐S, ADB‐HS, and ADB‐S obtained under different solvothermal conditions were investigated in terms of their morphologies, porosity, and their iodine enrichment performance in detail. It is noteworthy that excellent efficiency for removing iodine vapor was acquired for NDB‐S (≈425 wt %), ADB‐HS (≈345 wt %), and ADB‐S (≈342 wt %). Remarkably, NDB‐H exhibited an iodine capture capacity up to ≈443 wt %. Excellent reusability was obtained as well. Amorphous NDB‐H has accomplished an extremely high iodine capture performance, illustrating the great chance to exploit versatile amorphous POPs for iodine enrichment and removal based on Schiff‐base chemistry. [ABSTRACT FROM AUTHOR]

ABSTRACT: The random copolymers poly(LA‐ran‐CL) have improved properties of degradability, mechanical strength, elasticity, and permeability over the PLA and PCL homopolymers. However, the synthesis of such copolymers is still a great challenge in polymer chemistry. In this contribution, we develop a simple but well‐designed phenoxyimine Al complex (4) with bulky Ph2CH groups, which achieves controlled random copolymerization of rac‐LA and ɛ‐CL in a living manner (Ð = 1.06–1.09). The reactivity ratios of rac‐LA and ɛ‐CL (rLA and rCL) are 1.09 and 1.05 and the average sequence lengths of the lactidyl unit (LLA) and the caproyl unit (LCL) are in the range of 1.9–2.0 at different stages of conversion. In marked contrast, Al complexes (1–3) having less bulky substituents on the ligands only produce gradient copolymers. Furthermore, this strategy of catalyst design would be readily extended to other catalytic systems including β‐ketiminato Al complex (5). © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 611–617 [ABSTRACT FROM AUTHOR]

A new superbase, the cyclic trimeric phosphazene base (CTPB), was prepared with high yield and purity. In the presence of alcohol, the CTPB serves as a highly efficient organocatalyst for ring-opening polymerization of the 'non-polymerizable' γ-butyrolactone to offer well-defined poly(γ-butyrolactone) with high conversions (up to 98 %) at −60 °C. The produced polymers have high molecular weights (up to 22.9 kg mol−1) and low polydispersity distributions (1.27-1.50). NMR analysis of initiation process and the structural analysis of resulting polymers by MALDI-TOF suggest a mechanism involving an activating initiator which leads only to linear polymers with BnO/H chain ends. [ABSTRACT FROM AUTHOR]

In the transitional period between the Middle and the Late Triassic, the Indochina orogeny caused two tectonic events in South China: (1) the formation and uplift of the Qinling-Dabie orogenic belt along the northern margin of the South China Plate, due to its collision with the North China Plate; and 2) the development of a 1300-km-wide intra-continental orogen in the southeastern part of the South China Plate, which led to a northwestward movement of the foreland thrust-fold zone. These tectonic events resulted in the ending of the Yangtze Platform, and were a stable paleogeographic factor from the Eidacaran to the end of the Middle Triassic. This platform was characterized by the widespread development of shallow-water carbonates. After the end of the Yangtze Platform, the upper Yangtze foreland basin (or Sichuan foreland basin) was formed during the Late Triassic and became a accumulation site of fluvial deposits that are composed of related strata of the Xujiahe Formation. In western Sichuan Province, the Xujiahe Formation overlies the Maantang Formation shallow-water carbonate rocks of the Xiaotangzi Formation siliciclastic rocks (from shelf shales to littoral facies). The sequence-stratigraphic framework of the Upper Triassic in the upper Yangtze foreland basin indicates a particular alluvial architecture, characterized by sequences composed of (1) successions of low-energy fluvial deposits of high-accommodation phases, including coal seams, and (2) high-energy fluvial deposits of low-accommodation phases, including amalgamated river-channel sandstones. The spatial distribution of these fluvial deposits belonging to the Xujiahe Formation and its relative strata is characterized by gradual thinning-out, overlapping, and pinching-out toward both the east and south. This sedimentary record therefore expresses a particular sequence-stratigraphic succession of fluvial deposits within the filling succession of the foreland basin. The sequence-stratigraphic framework for the Upper Triassic in the Upper Yangtze region provides a record of the end of the Yangtze Platform and the formation of the upper Yangtze foreland basin. [ABSTRACT FROM AUTHOR]

A branch of the Paleo-Tethys Ocean once separated the north China plate from the south China plate. However, the mode of closure of the northeastern Paleo-Tethys Ocean during the Late Paleozoic to Early Mesozoic has been debated. One reason for this debate is that the collisional suture zone was later buried by large-scale thrust faults in the southern Qinling-Dabieshan orogen, which made it difficult to reconstruct the amalgamation of the supercontinent in central China. New regional geologic mapping provides stratigraphic and structural constraints on the mechanism of this ocean closure. Our results indicate that dextral transpressional suturing in the southern Qinling-Dabieshan foreland fold-thrust belt resulted in the formation of the northern Yangtze foreland basin, where the stratigraphy precisely shows the time-transgressive closure of the ocean, and the orogenic sediments shed over 1000 km westward from eastern China to the closing Paleo-Tethys. Therefore, we propose an oblique subduction model to describe the closure of the Paleo-Tethys Ocean. Our findings suggest that prolonged slab pull during the oblique subduction of the oceanic plate continued to drive deep continental subduction, thereby forming high- and ultrahigh-pressure metamorphic rocks and leading to sustained ocean closure. [ABSTRACT FROM AUTHOR]

Tobacco is a complex chemical matrix. The analysis of trace alkaline flavors in tobacco is very difficult because of the limited peak capacity of monodimensional GC. In the present study, a home-assembled twin-oven GC- GC- MS system, with MS detection in both dimensions, has been applied to the analysis of 20 alkaline volatiles in a variety of cut-tobacco samples. By transferring nine and six heart-cuts from the first apolar column to the second polar column in two separate runs, the potential mutual interference of adjacent isomeric targets and the complex matrix could be removed. For comparative purposes, a systematic comparison of both quantification and qualification results for the cut-tobacco sample as quality control was conducted between GC- GC- MS and GC- MS. The results showed that GC- GC- MS provided higher accuracy in peak assignment and quantification. And in GC- MS, the interferences of co-elution had caused both low matched similarity in peak assignment and false-negative/-positive results in quantification for some targets. Advantages of the developed GC- GC- MS method in the analysis of alkaline flavors are its high resolving power, reliability, and simplicity. [ABSTRACT FROM AUTHOR]

To investigate the soil-layer configuration requirement for numerical studying large-eddy scale atmosphere and land surface interactions, we conduct two experiments with an atmosphere and land surface coupled large-eddy model, one with the 'usual' soil-layer configuration and the other with a finer one. It is found that the former configuration prevents the soil to respond to atmospheric large eddies and the soil acts solely as a fixed external condition to the atmospheric turbulence, and is thus inadequate for large-eddy atmosphere and land surface coupled modeling. It is shown that soil-layer configuration has a profound impact on the simulated atmospheric boundary layer dynamics. Copyright © 2013 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The Xunhua, Guide and Tongren intermontane basin system in the NE Tibetan Plateau, situated near the Xining basin to the N and the Linxia basin to the E, is bounded by thrust fault-controlled ranges. These include to the N, the Riyue Shan, Laji Shan and Jishi Shan ranges, and to the S the northern West Qinling Shan ( NWQ). An integrated study of the structural geology, sedimentology and provenance of the Cenozoic Xunhua and Guide basins provides a detailed record of the growth of the NE Tibetan Plateau since the early Eocene. The Xining Group ( ca. 52-21 Ma) is interpreted as consisting of unified foreland basin deposits which were controlled by the bounding thrust belt of the NWQ. The Xunhua, Guide and Xining subbasins were interconnected prior to later uplift and damming by the Laji Shan and Jishi Shan ranges. Their sediment source, the NWQ, is constrained by strong unidirectional paleocurrent trends towards the N, a northward fining lithology, distinct and recognizable clast types and detrital zircon ages. Collectively, formation of this mountain-basin system indicates that the Tibetan Plateau expanded into the NWQ at a time roughly coinciding with Eocene to earliest Miocene continental collision between India and Eurasia. The Guide Group ( ca. 21-1.8 Ma) is inferred to have been deposited in the separate Xunhua, Guide and Tongren broken foreland basins. Each basin was filled by locally sourced alluvial fans, braided streams and deltaic-lacustrine systems. Structural, paleogeographic, paleocurrent and provenance data indicate that thrust faulting in the NWQ stepped northward to the Laji Shan from ca. 21 to 16 Ma. This northward shift was accompanied by E-W shortening related to nearly N-S-striking thrust faulting in Jishi Shan after 11-13 Ma. A lower Pleistocene conglomerate (1.8-1.7 Ma) was deposited by a through-flowing river system in the overfilled and connected Guide and Xunhua basins following the termination of thrust activity. All of the basin-mountain zones developed along the Tibetan Plateau's NE margin since Indian- Tibetan continental collision may have been driven by collision-induced basal drag of old slab remnants in the manner of N-dipping and flat-slab subduction, and their subsequent sinking into the deep mantle. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A series of titanium amido complexes (1‐Ti(NMe2)2 to 4‐Ti(NMe2)2) bearing NNO‐tridentate ligands was synthesized from the reactions of phenoxy‐imine‐amine ligands with one equivalent of Ti(NMe2)4. Subsequently, titanium dichloride complexes (1‐TiCl2 to 4‐TiCl2) were prepared by treatment of titanium amido complexes with excess Me3SiCl in toluene. All metal complexes were characterized by 1H and 13C NMR spectroscopy, and the molecular structures of complexes of 2‐Ti(NMe2)2, 2‐TiCl2, and 4‐TiCl2 in the solid state were determined by single‐crystal X‐ray diffraction. Upon activation with MAO, titanium dichloride complexes as single‐site catalysts were extremely active toward ethylene homopolymerization with great control on molecular weight and distribution. In particular, 3‐TiCl2/MAO exhibited an activity as high as 1.35 × 108 g(PE)·mol−1(Ti)·h−1 at 70°C and produced polyethylene with high molecular weight (41.7 × 104 g∙mol−1) and very narrow distribution (Đ = 1.23). In the presence of 1‐octene as comonomer, linear low‐density polyethylenes (LLDPEs) with ultrahigh molecular weights (Mw = 136—326 × 104 g∙mol−1) and narrow distributions (Đ = 1.20—1.50) were successfully synthesized. [ABSTRACT FROM AUTHOR]

A series of trichlorotitanium complexes containing 2-(1-(arylimino)propyl)quinolin-8-olates was synthesized by stoichiometric reaction of titanium tetrachloride with the corresponding potassium 2-(1-(arylimino)propyl)quinolin-8-olates and was fully characterized by elemental analysis, nuclear magnetic resonance spectroscopy, and by single-crystal X-ray diffraction study of representative complexes. All titanium complexes, when activated with methylaluminoxane, exhibited high catalytic activity toward ethylene polymerization [up to 1.15 × 106 g mol−1(Ti) h−1] and ethylene/α-olefin copolymerization [up to 1.54 × 106 g mol−1 (Ti) h−1]. The incorporation of comonomer was confirmed to amount up to 2.82 mol % of 1-hexene or 1.94 mol % of 1-octene, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

A series of 6‐(benzimidazol‐2‐yl)‐N‐organylpyridine‐2‐carboxamide were synthesized and transformed into 6‐benzimidazolylpyridine‐2‐carboxylimidate as dianionic tridentate ligands. Bis(2‐(6‐methylpyridin‐2‐yl)‐benzimidazolyl)titanium dichloride (C1) and titanium bis(6‐benzimidazolylpyridine‐2‐carboxylimidate) (C2–C8) were synthesized in acceptable yields. These complexes were systematically characterized by elemental and NMR analyses. Crystallographic analysis revealed the distorted octahedral geometry around titanium in both complexes C1 and C4. Using MAO as cocatalyst, all complexes exhibited from good to high catalytic activities for ethylene polymerization. The neutral bis(6‐benzimidazolylpyridine‐2‐carboxylimidate)titanium (C2–C8) showed high catalytic activities and good stability for prolonged reaction time and elevated reaction temperature; however, C1 showed a short lifetime in catalysis as being observed at very low activity after 5 min. The elevated reaction temperature enhanced the productivity of polyethylenes with low molecular weights, whereas the reaction with higher ethylene pressure resulted in better catalytic activity and resultant polyethylenes with higher molecular weights. At higher ratio of MAO to titanium precursor, the catalytic system generated better activity with producing polyethylenes with lower molecular weights. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3411–3423, 2008 [ABSTRACT FROM AUTHOR]

6‐Benzimidazolylpyridyl‐2‐carboximidic half‐titanocene complexes, Cp′TiLCl (Cp′ = C5H5, MeC5H4, C5Me5, L = 6‐benzimidazolylpyridine‐2‐carboxylimidic, C1–C13), were synthesized and characterized along with single‐crystal X‐ray diffraction. The half‐titanocene chlorides containing substituted cyclopentadienyl groups, especially pentamethylcyclopentadienyl groups were more stable, while those without substituents on the cyclopentadienyl groups were easily transformed into their dimeric oxo‐bridged complexes, (CpTiL)2O (C14 and C15). In the presence of excessive amounts of methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), all half‐titanocene complexes showed high catalytic activities for ethylene polymerization. The substituents on the Cp groups affected the catalytic behaviors of the complexes significantly, with less substituents favoring increased activities and higher molecular weights of the resultant polyethylenes. Effects of reaction conditions on catalytic behaviors were systematically investigated with catalytic systems of mononuclear C1 and dimeric C14. With C1/MAO, large MAO amount significantly increases the catalytic activity, while the temperature only has a slight effect on the productivity. In the case of C14/MAO catalytic system, temperature above 60 °C and Al/Ti value higher than 5000 were necessary to observe good catalytic activities. In both systems, higher reaction temperature and low cocatalyst amount gave the polyethylenes with higher molecular weights. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3396–3410, 2008 [ABSTRACT FROM AUTHOR]

The Dabieshan orogenic belt is a zone of long-lived shortening with late-stage extension that formed during Mesozoic time in central China. Regional basin analysis coupled with structural cross sections provides a means of reconstructing the paleogeography of the region from Triassic continental collision through early Tertiary extension. The overall distribution of different basin types in the orogenic belt indicates that there was a prolonged period of shortening throughout the Mesozoic that became less intense over time. Meanwhile, extension became more common from Jurassic into Tertiary time. Either compression or extension was isochronous but limited to different geographic regions and/or crustal levels or alternated repeatedly orogen-wide through time. Nonetheless, the orogen underwent gradual transition from overall shortening and crustal thickening to dominantly extension and rift basin formation although these events overlapped in time from the Jurassic through Early Cretaceous. Penecontemporaneous compression and extension across the orogen may reflect long-term (>100 m.y.) shortening and crustal thickening leading to gravitational spreading of the resultant thick crustal welt. We suspect that this prolonged history of shortening across two nearby (∼100 km apart) suture zones played some role in the exhumation of ultrahigh-pressure rocks from beneath the Dabieshan. [ABSTRACT FROM AUTHOR]