The Qilian Orogen at the northern margin of the Tibetan Plateau is a type suture zone that recorded a complete history from continental breakup to ocean basin evolution, and to the ultimate ...continental collision in the time period from the Neoproterozoic to the Paleozoic. The Qilian Ocean, often interpreted as representing the “Proto-Tethyan Ocean”, may actually be an eastern branch of the worldwide “Iapetus Ocean” between the two continents of Baltica and Laurentia, opened at ≥710Ma as a consequence of breakup of supercontinent Rodinia.
Initiation of the subduction in the Qilian Ocean probably occurred at ~520Ma with the development of an Andean-type active continental margin represented by infant arc magmatism of ~517–490Ma. In the beginning of Ordovician (~490Ma), part of the active margin was split from the continental Alashan block and the Andean-type active margin had thus evolved to western Pacific-type trench–arc–back-arc system represented by the MORB-like crust (i.e., SSZ-type ophiolite belt) formed in a back-arc basin setting in the time period of ~490–445Ma. During this time, the subducting oceanic lithosphere underwent LT-HP metamorphism along a cold geotherm of ~6–7°C/km.
The Qilian Ocean was closed at the end of the Ordovician (~445Ma). Continental blocks started to collide and the northern edge of the Qilian–Qaidam block was underthrust/dragged beneath the Alashan block by the downgoing oceanic lithosphere to depths of ~100–200km at about 435–420Ma. Intensive orogenic activities occurred in the late Silurian and early Devonian in response to the exhumation of the subducted crustal materials.
Briefly, the Qilian Orogen is conceptually a type example of the workings of plate tectonics from continental breakup to the development and evolution of an ocean basin, to the initiation of oceanic subduction and formation of arc and back-arc system, and to the final continental collision/subduction and exhumation.
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► Early Paleozoic oceanic suture zone. ► Qilian ocean generated by break-up of the Rodinia supercontinent. ► Initiation of the subduction in the Qilian Ocean at ~ 520 Ma. ► Ophiolites, arc magmatism and high-pressure metamorphism. ► Ocean subduction and continental collision.
A tholeiite–boninite terrane occurs as a ~4.5-km-thick massif with lavas and intrusions in the Dachadaban (DCDB) area, the middle part of the North Qilian oceanic-type suture zone. It comprises two ...distinct lithological groups: the lower tholeiite unit and the upper boninite unit. The lower tholeiite unit consists of massive lava flows and subordinate gabbro intrusions with MORB-like characteristics that could represent 5–6% melting of an enriched MORB mantle. In contrast, the overlying boninite unit consists of pillow lavas, dolerite dykes and gabbro intrusions and shows high-Ca boninite features that may be formed by continuous melting of the extremely refractory mantle with the aid of a combination of the elevated mantle potential temperature of 1380–1460°C at depths of 42–66km and involvement of slab-derived hydrous fluids/melts. Zircon U–Pb SHRIMP dating shows that lower tholeiite magmatism lasted for at least 12M.y. from 517Ma to 505Ma and upper boninite volcanism occurred between 505 and 487Ma, which is consistent with the earliest age (486±7Ma) of the SSZ-type ophiolite belt immediately north of the Dachaidaban (DCDB) tholeiite–boninite terrane. The lower tholeiites are considered to represent the products of earliest infant arc magmatism by decompression-induced partial melting of the relatively “dry” and fertile upwelling mantle in response to the onset of subduction. The upper boninite unit with younger age of 487±9Ma is interpreted as earliest products of infant arc splitting and subsequent back-arc basin development. Therefore, the long-lived DCDB tholeiite–boninite sequence presents a key lithological record of early stages of supra-subduction zone magmatic activity evolved from subduction initiation at ~517Ma to back-arc extension at ~487Ma.
► Tholeiite–boninite terrane with lower tholeiitic unit and upper boninite unit. ► Infant arc magmaism at about 520Ma. ► Long-lived (~30Myrs) magmatism from tholeiite to boninite. ► Back-arc extension led to the infant arc splitting and eventual back-arc basin spreading. ► Early Paleozoic oceanic suture zone.
Bismuth-based solar cells have exhibited some advantages over lead perovskite solar cells for nontoxicity and superior stability, which are currently two main concerns in the photovoltaic community. ...As for the perovskite-related compound (CH3NH3)3Bi2I9 applied for solar cells, the conversion efficiency is severely restricted by the unsatisfactory photoactive film quality. Herein we report a novel two-step approach high-vacuum BiI3 deposition and low-vacuum homogeneous transformation of BiI3 to (CH3NH3)3Bi2I9for highly compact, pinhole-free, large-grained films, which are characterized with absorption coefficient, trap density of states, and charge diffusion length comparable to those of some lead perovskite analogues. Accordingly, the solar cells have realized a record power conversion of efficiency of 1.64% and also a high external quantum efficiency approaching 60%. Our work demonstrates the potential of (CH3NH3)3Bi2I9 for highly efficient and long-term stable solar cells.
In present work, nylon 6 (PA6) was grafted onto carbon fiber surface by means of anionic grafting to enhance the interfacial adhesion between carbon fiber and nylon 12. The effect of different ...grafting amount was studied by DTA, the tensile strength of PA6-CF/PA12 composites possessed a highest increase of 30.8% from 53.9 MPa to 70.5 MPa. The SEM of fracture surface of PA6-CF/PA12 composites demonstrated that the mechanical adhesion between carbon fiber and matrix PA12 was improved significantly. The experiments results indicate that it is an effective CF surface treatment to enhance the interfacial bonding with nylon 12 matrix by grafting nylon 6 to carbon fiber surface.
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•Grafting PA6 onto carbon fiber surface is an effective method to enhance the mechanical strength.•The tensile strength possesses a highest increase of 30.8% from 53.9 MPa to 70.5 MPa.•The amount of nylon 6 lies on the amount of initiator and the reaction time.
Nylon 6 (PA6) grafted onto carbon fiber (CF) after chemical oxidation treatment was in an attempt to reinforce the mechanical properties of carbon fiber composites. Scanning electronic microscopy (SEM), Fourier transform infrared analysis (FT-IR), X-ray photoelectron spectroscope (XPS) and thermogravimetric analysis (TG) were selected to characterize carbon fibers with different surface treated. Experimental results showed that PA6 was grafted uniformly on the fiber surface through the anionic polymerization. A large number of functional groups were introduced to the fiber surface and the surface roughness was increased. After grafting PA6 on the oxidized carbon fibers, it played an important role on improving the interfacial adhesion between the fibers and the matrix by improving PA12 wettability, increasing chemical bonding and mechanical interlocking. Compared with the desized CF composites, the tensile strength of PA6-CF/PA12 composites was increased by 30.8% from 53.9 MPa to 70.2 MPa. All results indicated that grafting PA6 onto carbon fiber surface was an effective method to enhance the mechanical strength of carbon fiber/nylon 12 composites.
Androgen receptor splice variant 7 (AR-V7), a form of ligand-independent and constitutively activating variant of androgen receptor (AR), is considered as the key driver to initiate ...castration-resistant prostate cancer (CRPC). Because AR-V7 lacks ligand-binding domain, the AR-targeted therapies that aim to inactivate AR signaling through disrupting the interaction between AR and androgen are limited in CRPC. Thus, the emergence of AR-V7 has become the greatest challenge for treating CRPC. Targeting protein degradation is a recently proposed novel avenue for cancer treatment. Our previous studies have been shown that the oncoprotein AR-V7 is a substrate of the proteasome. Identifying novel drugs that can trigger the degradation of AR-V7 is therefore critical to cure CRPC. Here we show that nobiletin, a polymethoxylated flavonoid derived from the peel of Citrus fruits, exerts a potent anticancer activity via inducing G0/G1 phase arrest and enhancing the sensitivity of cells to enzalutamide in AR-V7 positive PC cells. Mechanically, we unravel that nobiletin selectively induces proteasomal degradation of AR-V7 (but not AR). This effect relies on its selective inhibition of the interactions between AR-V7 and two deubiquitinases USP14 and USP22. These findings not only enrich our understanding on the mechanism of AR-V7 degradation, but also provide an efficient and druggable target for overcoming CRPC through interfering the stability of AR-V7 mediated by the interaction between AR-V7 and deubiquitinase.
It has been well known that androgen receptor (AR) is critical to prostate cancer development and progression. It has also been documented that AR is expressed in more than 60% of breast tumors, ...which promotes the growth of estrogen receptor-negative (ER
)/AR-positive (AR
) breast cancer cells. Thus, AR might be a potential therapeutic target for AR-positive/ER-negative breast cancer patients. Previously we reported that in prostate cancer cells proteasome-associated deubiquitinase ubiquitin-specific protease 14 (USP14) stabilized AR protein level by removing its ubiquitin chain. In the current study, we studied the USP14-AR protein interaction and cell proliferation status after USP14 reduction or inhibition in breast cancer cells, and our results support the conclusion that targeting USP14 is a novel strategy for treating AR-responsive breast cancer. We found that inhibition of USP14 accelerated the K48-ubiquitination and proteasome-mediated degradation of AR protein. Additionally, both genetic and pharmacological inhibition of USP14 significantly suppressed cell proliferation in AR-responsive breast cancer cells by blocking G
/G
to S phase transition and inducing apoptosis. Moreover, AR overexpression inhibited USP14 inhibition-induced events, suggesting that AR deubiquitination by USP14 is critical for breast cancer growth and USP14 inhibition is a possible strategy to treat AR-positive breast cancer.
In the evolving business landscape, utility firms are undergoing transformative digital changes. The purpose of this study is to examine the unexplored link between utility firms' digital ...transformation and performance, by utilizing unique data from Chinese listed utilities. Empirical findings show a positive correlation between digital transformation and enhanced performance, with financial constraints and environmental performance as identified mechanisms. The research enriches understanding of digital transformation's economic consequences, providing practical insights for implementation, especially for environmentally conscious firms. Considering textual analysis and sample size limitations, future studies could assess utility firms' digital transformation across diverse economies with a more thorough evaluation of a firm's level of digital transformation.
Metal-organic frameworks are recognized as active electrode materials for rechargeable batteries due to their structural diversity, abundant electrochemical active sites and large ion diffusion ...channels. Herein, nickel-terephthalic acid metal-organic frameworks (Ni-PTA MOFs) with different crystal and morphology structures are synthesized via a facile solvothermal method by simply adjusting the nature of solvent. Due to the fewest guest molecules and porous structure, the Ni-PTA resulting from the combinations of DMF and EtOH exhibits the comparatively higher chemical/thermal stability and shortened ion diffusion pathway. As a result, it exhibits a high discharge/charge capacity of 2196.4 and 1762.3 mAh g
−1
at the first cycle and retains 1300 mAh g
−1
after 50 cycles at 100 mA g
−1
when tested as anode materials for Li-ion batteries. Even when the current density reaches 4000 mA g
−1
, it maintains a capacity of 452 mAh g
−1
. This work provides possibilities for regulating the crystal and morphology structure of MOFs as high performance anode materials for lithium ion batteries.
Prostate cancer (PCa) remains a challenge worldwide. Due to the development of castration-resistance, traditional first-line androgen deprivation therapy (ADT) became powerlessness. Epidermal growth ...factor receptor (EGFR) is a well characterized therapeutic target to treat colorectal carcinoma and non-small cell lung cancer. Increasing studies have unraveled the significance of EGFR and its downstream signaling in the progression of castration-resistant PCa.
MTS, colony formation and Edu staining assays were used to analyze the cell proliferation of PCa cells. Flow cytometry was used to analyze PCa cell cycle distribution and cell apoptosis. Western blot was used to measure the expression of key proteins associated with cell cycle progression, apoptosis and EGFR signaling pathways. Transfection of exogenous small interfering RNA (siRNA) or plasmid was used to intervene specific gene expression. Nude mouse model was employed to test the in vivo effect of Spautin-1.
The current study reveals that Spautin-1, a known inhibitor of ubiquitin-specific peptidase 10 (USP10) and USP13, inhibits EGFR phosphorylation and the activation of its downstream signaling. Inhibition of EGFR signaling induced by Spautin-1 leads to cell cycle arrest and apoptosis of PCa in a USP10/USP13 independent manner. The application of Spautin-1 reduces the expression of glucose transporter 1 (Glut1) and dramatically induces cell death under glucose deprivation condition. In vivo experiments show a potent anti-tumor effect of Spautin-1 alone and in combination with Enzalutamide.
This study demonstrates the therapeutic potential of EGFR signaling inhibition by the use of Spautin-1 for PCa treatment.
Breast cancer has the highest incidence and mortality in women worldwide. There are 70% of breast cancers considered as estrogen receptor α (ERα) positive. Therefore, the ERα-targeted therapy has ...become one of the most effective solution for patients with breast cancer. Whereas a better understanding of ERα regulation is critical to shape evolutional treatments for breast cancer. By exploring the regulatory mechanisms of ERα at levels of post-translational modifications, we identified the deubiquitinase USP15 as a novel protector for preventing ERα degradation and a critical driver for breast cancer progression. Specifically, we demonstrated that USP15 promoted the proliferation of ERα
, but not ERα
breast cancer, in vivo and in vitro. Meanwhile, USP15 knockdown notably enhanced the antitumor activities of tamoxifen on breast cancer cells. Importantly, USP15 knockdown induced the downregulation of ERα protein via promoting its K48-linked ubiquitination, which is required for proliferative inhibition of breast cancer cells. These findings not only provide a novel treatment for overcoming resistance to endocrine therapy, but also represent a therapeutic strategy on ERα degradation by targeting USP15-ERα axis.
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