119 research outputs found

    A Discussion on the Detachment Structural Deformation and Its Influence on Pore Structure Evolution in Shale on the Western of the Xuefeng Mountain, South China

    Get PDF
    Detachment structures occur widely in the crust, and it is the commonest and most important deformation type developed in the region between orogenic belts and basins. Organic-rich shale, as the weak layers, usually acts as slippery layers in detachment structural deformation systems. The ā€œcomb-likeā€ and ā€œtough-likeā€ fold belts on the western side of the Xuefeng Mountain result from the multilayer detachment, and their formation is different from the typical Jura type structures. The reason is that there are several detachment layers and detachment systems in the stratigraphic column from the Neoproterozoic upwards to the Mesozoic in the study area. As the stress decoupling role, the shale slippery layers tend to undergo strong deformation in the detachment systems and impacted on pore structure evolution in the shale. In order to obtain the detachment structural deformation and its influence on pore structure evolution in shale on the Middle and Upper Yangtze, the structural and textural, geochemical and mineralogical properties analysis, porosity and pore structure feature investigations are performed using shale samples collected from the same shale bed of the Longmaxi Formations (Lower Silurian) of Western of the Xuefeng Mountain, South China

    Epidermal growth factor receptor restoration rescues the fatty liver regeneration in mice

    Get PDF
    Hepatic steatosis is a common histological finding in obese patients. Even mild steatosis is associated with delayed hepatic regeneration and poor outcomes following liver resection or transplantation. We sought to identify and target molecular pathways that mediate this dysfunction. Lean mice and mice made obese through feeding of a high-fat, hypercaloric diet underwent 70 or 80% hepatectomy. After 70% resection, obese mice demonstrated 100% survival but experienced increased liver injury, reduced energy stores, reduced mitoses, increased necroapoptosis, and delayed recovery of liver mass. Increasing liver resection to 80% was associated with mortality of 40% in lean and 80% in obese mice (P < 0.05). Gene expression profiling showed decreased epidermal growth factor receptor (EGFR) in fatty liver. Meta-analysis of expression studies in mice, rats, and patients also demonstrated reduction of EGFR in fatty liver. In mice, both EGFR and phosphorylated EGFR decreased with increasing percent body fat. Hydrodynamic transfection of EGFR plasmids in mice corrected fatty liver regeneration, reducing liver injury, increasing proliferation, and improving survival after 80% resection. Loss of EGFR expression is rate limiting for liver regeneration in obesity. Therapies directed at increasing EGFR in steatosis might promote liver regeneration and survival following hepatic resection or transplantation

    PKCĪµ Activator Protects Hippocampal Microvascular Disruption and Memory Defect in 3ƗTg-Alzheimer\u27s Disease Mice with Cerebral Microinfarcts

    Get PDF
    BACKGROUND: Current evidence suggests that microvessel disease is involved in Alzheimer\u27s disease (AD). Cerebrovascular disease correlates with cardiovascular disease and is complicated in ā‰ˆ40% of AD patients. The protein kinase C (PKC) Īµ activator DCPLA can stimulate human antigen (Hu) R that prevents degradation and promotes the translation of mitochondrial Mn-superoxide dismutase (MnSOD) and vascular endothelial growth factor-A (VEGF) mRNAs. METHODS: To induce brain microinfarcts, we injected triple transgenic (3ƗTg) and wild-type (WT) control mice with microbeads (20ā€‰Ī¼m caliber) into common carotid arteries, with or without the DCPLA-ME (methyl-ester) for 2ā€‰weeks. After water maze training, mice at 16ā€‰months old were examined for confocal immunohistochemistry at a single cell or microvessel level in the hippocampal CA1 area, important for spatial memory storage, and in the dorsal hippocampus by western blots. RESULTS: In 3ƗTg mice without cerebral microinfarcts, an accelerating age-related increase in (mild) oxidative stress and hypoxia inducible factor (HIF)-1Ī±, but a reduction in VEGF, mitochondrial transcription factor A (TFAM), and MnSOD were associated with capillary loss. The change was less pronounced in arterioles. However, in 3ƗTg mice with cerebral microinfarcts, increasing arteriolar diameter and their wall cells were related with the strong oxidative DNA damage 8-hydroxy-2\u27-deoxyguanosine (8-OHdG), apoptosis (cleaved caspase 3), and sustained hypoxia (increased HIF-1Ī± and VEGF/PKCĪµ/extracellular signal regulated kinase or ERK pathway). Microocclusion enhanced the loss of the synaptic marker spinophilin, astrocytic number, and astrocyte-vascular coupling areas and demyelination of axons. DCPLA-ME prevented spatial memory defect; strong oxidative stress-related apoptosis; sustained hypoxia (by reducing HIF-1Ī± and VEGF); and exaggerated cell repair in arteriolar walls, pericapillary space dilation, neuro-glial-vascular disruption, and demyelination. CONCLUSION: In conclusion, in 3ƗTg mice with cerebral microinfarcts, sustained hypoxia (increased HIF-1Ī± and VEGF signals) is dominant with arteriolar wall thickening, and DCPLA has a protective effect on sustained hypoxia

    Constraints for post-orogenic extension of the northern margin of the Qaidam Basin from the Late Silurianā€“Late Devonian igneous rocks in the Gahaiā€“Nanshan area

    Get PDF
    Objective Ā The northern margin tectonic zone of the Qaidam Basin underwent a transition from oceanic subduction to continental subduction during the Early Paleozoic, resulting in the formation of the ultrahigh-pressure metamorphic zone known as the northern Qaidam tectonic zone (NQTZ). There has been a longstanding debate regarding the collapse time of the NQTZ. The Maoniushan Formation has long been regarded as a sign of the end of orogeny; however, recent studies show that the Maoniushan Formation has spanned a long time, and it is controversial when the orogenic belt began to collapse. This study aims to determine the age and genetic background of the Maoniushan Formation and to understand the tectonic transition process of the northern Qinghaiā€“Tibet Plateau from the Proto-Tethys to the Paleo-Tethys. Ā  Methods Ā Deep-earth samples, including volcanic and intrusive rocks, offer valuable insights into the activity of the crust during this period. In order to investigate the volcaniclastic rocks and granites in the Gahaiā€“Nanshan area, located in the eastern section of the NQTZ, zircon LAā€“ICPā€“MS Uā€“Pb chronology and Luā€“Hf isotope methods were employed to explore the formation age of igneous rocks and the characteristics of source rocks. Ā  Results Ā The zircon Uā€“Pb chronology reveals that the volcaniclastic rocks of the Maoniushan Formation originated approximately 423 Ma. Furthermore, the intrusive granite was formed at 370 Ma, indicating that the volcanic eruption occurred during the Late Silurian, while the subsequent intrusion and crystallization of the granites occurred during the Late Devonian. The zircon Luā€“Hf isotope data reveals that the ĪµHf(t) values of the Late Silurian tuffs are concentrated within the range of ā€“11.5 to ā€“8.3, and the corresponding two-stage Hf model ages are primarily between 1945ā€“2133 Ma. These results indicate that the volcanic rocks predominantly originated from partially melting ancient crustal materials. In contrast, the ĪµHf(t) values of the Late Devonian intrusive granites exhibit a distribution within the range of 3.9ā€“9.1, accompanied by two-stage Hf model ages primarily falling within the 792ā€“1118 Ma range. The results suggest that the granites mainly resulted from partially melting Meso-Neoproterozoic crustal materials. Based on a comprehensive analysis of regional geological and petrological data, it is postulated that the Late Silurianā€“Early Devonian witnessed pronounced orogenesis resulting from continental deep subduction. This event led to substantial crustal thickening in the NQTZ, where the thickened crustal basement of the Oulongbruk experienced partial melting, ultimately giving rise to the volcanic rocks observed during this period. During the Late Devonian, delamination of the thickened crust facilitated the upwelling of the asthenosphere mantle, triggering regional crustal extension. The interaction between mantle material and crust results in the formation of graniticā€“volcanic rocks. Ā  Conclusion Ā The Maoniushan Formation in the region encapsulates a significant period, making it unsuitable to represent the end of orogeny. Late Devonian igneous rocks indicate that the NQTZ entered a period of substantial crustal extension during this time. [ Significance ] The late Devonian igneous rocks of Maoniushan Formation regionally mark the end of orogeny and the beginning of the Paleo-Tethys tectonic domain

    Numerical analysis of an implicit fully discrete local discontinuous Galerkin method for the fractional Zakharovā€“Kuznetsov equation

    Get PDF
    In this paper we develop and analyze an implicit fully discrete local discontinuous Galerkin (LDG) finite element method for a time-fractional Zakharovā€“Kuznetsov equation. The method is based on a finite difference scheme in time and local discontinuous Galerkin methods in space. We show that our scheme is unconditional stable andĀ LĀ 2Ā error estimate for the linear case with the convergence rateĀ Ā through analysis

    Rice Hypersensitive Induced Reaction Protein 1 (OsHIR1) associates with plasma membrane and triggers hypersensitive cell death

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>In plants, HIR (Hypersensitive Induced Reaction) proteins, members of the PID (Proliferation, Ion and Death) superfamily, have been shown to play a part in the development of spontaneous hypersensitive response lesions in leaves, in reaction to pathogen attacks. The levels of HIR proteins were shown to correlate with localized host cell deaths and defense responses in maize and barley. However, not much was known about the HIR proteins in rice. Since rice is an important cereal crop consumed by more than 50% of the populations in Asia and Africa, it is crucial to understand the mechanisms of disease responses in this plant. We previously identified the rice HIR1 (OsHIR1) as an interacting partner of the OsLRR1 (rice Leucine-Rich Repeat protein 1). Here we show that OsHIR1 triggers hypersensitive cell death and its localization to the plasma membrane is enhanced by OsLRR1.</p> <p>Result</p> <p>Through electron microscopy studies using wild type rice plants, OsHIR1 was found to mainly localize to the plasma membrane, with a minor portion localized to the tonoplast. Moreover, the plasma membrane localization of OsHIR1 was enhanced in transgenic rice plants overexpressing its interacting protein partner, OsLRR1. Co-localization of OsHIR1 and OsLRR1 to the plasma membrane was confirmed by double-labeling electron microscopy. Pathogen inoculation studies using transgenic <it>Arabidopsis thaliana </it>expressing either OsHIR1 or OsLRR1 showed that both transgenic lines exhibited increased resistance toward the bacterial pathogen <it>Pseudomonas syringae </it>pv. <it>tomato </it>DC3000. However, <it>OsHIR1 </it>transgenic plants produced more extensive spontaneous hypersensitive response lesions and contained lower titers of the invading pathogen, when compared to <it>OsLRR1 </it>transgenic plants.</p> <p>Conclusion</p> <p>The OsHIR1 protein is mainly localized to the plasma membrane, and its subcellular localization in that compartment is enhanced by OsLRR1. The expression of OsHIR1 may sensitize the plant so that it is more prone to HR and hence can react more promptly to limit the invading pathogens' spread from the infection sites.</p

    Projective Quasiparticle Interference of a Single Scatterer to Analyze the Electronic Band Structure of ZrSiS

    Full text link
    Quasiparticle interference (QPI) of the electronic states has been widely applied in scanning tunneling microscopy (STM) to analyze the electronic band structure of materials. Single-defect induced QPI reveals defect-dependent interaction between a single atomic defect and electronic states, which deserves special attention. Due to the weak signal of single-defect-induced QPI, the signal-to-noise ratio (SNR) is relatively low in a standard two-dimensional QPI measurement. In this paper, we introduce a projective quasiparticle interference (PQPI) method, in which a one-dimensional measurement is taken along high-symmetry directions centered on a specified defect. We apply the PQPI method to a topological nodal-line semimetal ZrSiS. We focus on two special types of atomic defects that scatter the surface and bulk electronic bands. With enhanced SNR in PQPI, the energy dispersions are clearly resolved along high symmetry directions. We discuss the defect-dependent scattering of bulk bands with the non-symmorphic symmetry-enforced selection rules. Furthermore, an energy shift of the surface floating band is observed and a new branch of energy dispersion (q6) is resolved. This PQPI method can be applied to other complex materials to explore defect-dependent interactions in the future.Comment: 21 pages, 5 figures, supplementary 3 pages, 2 figure
    • ā€¦
    corecore