A high-speed rotating rotor system mounted on a moving vehicle is inevitably subjected to parametric excitations and exciting forces induced by base motions. Dynamic characteristics of a ...rotor-bearing system supported by squeeze-film damper with retainer spring subjected to unbalance and support motions are investigated. Using Lagrange’s principle, equations of motion for rotor system relative to a moving support are derived. Under base excitations, steady-state and transient responses are analyzed by frequency–amplitude curve, waveform, orbit, frequency spectrum, and Poincaré map. Changing with rotating speed or base harmonic frequency, journal motions are analyzed by bifurcation diagram. The results indicate that under base axial rotation, increasing base angular velocity, first two critical speeds decrease but resonant amplitudes increase slightly. The journal whirls around the static eccentricity with noncircular orbit. Under base lateral rotation, critical speeds, and resonant amplitudes remain essentially unchanged, but orbit’s deviation is related to base angular velocity. Excited by base harmonic translation, the integral multiples of fundamental frequency
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are stimulated, changing the motions from periodic to quasiperiodic. Overall, it provides a flexible approach with good expandability to predict dynamic characteristics of squeeze-film damped rotor system under base motions.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Under parametric excitations and external forces induced by base motions, dynamic behavior of an on-board rotor system supported by squeeze film damper (SFD) considering fluid inertia was ...investigated. Based on perturbation method, oil-film pressure and three-dimensional velocities were represented by first-order functions of the Reynolds number. Using finite difference and numerical integration, an oil-film inertia SFD model was established to calculate pressure distribution and oil-film forces. Excited by time-varying base motions, dynamic responses and bifurcation behavior of SFD-rotor system were analyzed by Newmark–HHT method. The results indicate that when the journal whirls at a large eccentricity ratio, the pressure distribution is sensitive to oil-film inertia, reducing radial force while increasing tangential force. For high rotating speed and large eccentricity, the inertia effect dampens resonant amplitude. Under base transverse rotations, the journal’s whirling orbits deviate from the bearing’s center, and sub-harmonic frequencies appear with fundamental frequency. Under base harmonic translation, the journal’s motion is transformed from periodic to quasi-periodic, and the stability is gradually deteriorated with harmonic frequency. Overall, a flexible approach is established to calculate dynamic behavior of SFD-rotor system considering oil-film inertia under base motions, which provides technical support for dynamic design of on-board rotor systems in gas turbines.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•This is the first to identify Mesoarchean (3.11–2.85 Ga) rocks in the southern Yangtze Block.•1.94 and 1.89 Ga granitic magmatism recorded in the Cuoke complex.•Multistage crustal growth and ...reworking occurred in the Cuoke complex.•The Yangtze Block experienced intense metamorphism and magmatism in the context of Nuna assembly.
The newly identified Cuoke Complex preserves voluminous early Precambrian granitoids, bearing key information for the early evolution of the Yangtze Block, South China. Here, we report new field observations, petrology, zircon U-Pb-Hf isotopes and trace elements for eight granitoids from this complex. The analyzed zircon domains are of magmatic origin, as evidenced by their oscillatory zoning, high Th/U ratios and magmatic rare earth element patterns. Three trondhjemitic gneisses yield crystallization ages of 3.11–3.06 Ga, documenting the oldest known rocks in the southern Yangtze Block. Their εHf(t) values vary from −3.2 to + 2.6 with depleted mantle two-stage (TDM2) model ages of 3.6–3.3 Ga, indicating reworking of Paleoarchean crustal materials. Three gneissic granitoids crystallized at 2.86–2.85 Ga and reveal a significant episode of granitoid magmatism in the late Mesoarchean. They possess positive εHf(t) values (+0.2 to +5.0) and slightly older TDM2 model ages (3.3–3.0 Ga), suggesting that these granitoids were most likely derived from remelting of juvenile continental crust. Two monzogranites with crystallization ages of 1.94 and 1.89 Ga display negative εHf(t) values (−13.0 to −8.1) and older TDM2 model ages (3.3–3.1 Ga), indicating substantial involvement of ancient crustal materials. Available zircon U-Pb-Hf isotopic data from the Cuoke Complex have revealed that the earliest crustal growth probably occurred in the early Paleoarchean, with significant crustal growth and reworking during the early Mesoarchean, followed by multistage crustal reworking during the late Mesoarchean to Paleoproterozoic. Integrating the results of this study with records from other Archean basement complexes in the Yangtze Block (i.e., Kongling, Zhongxiang, Douling, Yudongzi and Phan Si Pan), we propose that these complexes have diverse formation histories and generally experienced tectonothermal events at ca. 2.0–1.9 Ga, probably responding to the global-scale assembly of the Nuna supercontinent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Deubiquitination of NLRP3 has been suggested to contribute to inflammasome activation, but the roles and molecular mechanisms are still unclear. We here demonstrate that ABRO1, a subunit of the BRISC ...deubiquitinase complex, is necessary for optimal NLRP3‐ASC complex formation, ASC oligomerization, caspase‐1 activation, and IL‐1β and IL‐18 production upon treatment with NLRP3 ligands after the priming step, indicating that efficient NLRP3 activation requires ABRO1. Moreover, we report that ABRO1 deficiency results in a remarkable attenuation in the syndrome severity of NLRP3‐associated inflammatory diseases, including MSU‐ and Alum‐induced peritonitis and LPS‐induced sepsis in mice. Mechanistic studies reveal that LPS priming induces ABRO1 binding to NLRP3 in an S194 phosphorylation‐dependent manner, subsequently recruiting the BRISC to remove K63‐linked ubiquitin chains of NLRP3 upon stimulation with activators. Furthermore, deficiency of BRCC3, the catalytically active component of BRISC, displays similar phenotypes to ABRO1 knockout mice. Our findings reveal an ABRO1‐mediated regulatory signaling system that controls activation of the NLRP3 inflammasome and provide novel potential targets for treating NLRP3‐associated inflammatory diseases.
Synopsis
ABRO1 binds to NLRP3 in an S194 phosphorylation‐dependent manner upon priming, subsequently acting as a scaffold to assemble the BRISC. NLRP3 activation signals then trigger the BRISC‐dependent removal of K63‐linked ubiquitin on NLRP3 LRRs, followed by assembly of the NLRP3 inflammasome.
Abro1−/− and Brcc3−/− macrophages show specific defective activation of the NLRP3 inflammasome.
ABRO1 binds to NLRP3 upon priming, which dependents on the phosphorylation of NLRP3 at S194 and the activity of JNK kinase.
ABRO1 recruits BRISC to NLRP3, and mediates the BRISC‐dependent removal of K63‐linked ubiquitin on NLRP3 LRRs upon stimulation with activators.
Mice lacking ABRO1 or BRCC3 exhibit severely reduced inflammation in response to in vivo models of NLRP3 activation.
Loss of the substrate‐targeting ABRO1 subunit of BRISC deubiquitinase attenuates NLRP3‐associated inflammatory diseases in mice, making BRISC a potential new target for treatment of such conditions.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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•We present the rarely reported early Paleoproterozoic magmatic records in the Yangtze Block.•The ca. 2.36 Ga Cuoke monzogranites formed within post-collisional setting.•They were ...likely derived from a source comprising mainly Mesoarchean crustal materials.•The SW Yangtze Block likely underwent a collision event related to the Arrowsmith orogeny.•A spatial connection between Yangtze and Laurentia in the Columbia supercontinent is favored.
The early Paleoproterozoic is an essential period for understanding the early tectonic evolution of the Yangtze Block and its reconstruction in the Columbia supercontinent, whereas these issues are largely unknown due to the scarce preservation of early Paleoproterozoic geological records. This study presents rarely reported early Paleoproterozoic granitoids from the southwestern Yangtze Block, with integrated studies of zircon U-Pb ages, Lu-Hf isotopic compositions and whole-rock geochemistry. Magmatic zircon U-Pb dating for two monzogranite samples yields weighted mean 207Pb/206Pb ages of 2359 ± 16 Ma and 2363 ± 16 Ma, providing unambiguous evidence for the presence of early Paleoproterozoic magmatism in the Yangtze Block. All the samples have high A/CNK values of 1.30–1.61, typical of S-type granite. These rocks have low total REE contents of 72.5–139.0 ppm with marked enrichment in LREEs ((La/Yb)N = 10.73–23.83) and conspicuously negative Eu anomalies (Eu/Eu* = 0.46–0.55). The rocks exhibit uniform primitive mantle-normalized trace element patterns with enrichment in Rb, Th, U and Pb and depletion in Sr, Nb, Hf and Ti. These dated zircon grains have consistent negative εHf(t) values of −6.2 to −2.8 and TDM2 ages of ca. 2.97–3.16 Ga, indicative of Mesoarchean crustal materials as their magma source. Considering the existence of the ca. 2.36 Ga regional high-grade tectono-metamorphic event, we propose that the ca. 2.36 Ga monzogranites were most likely generated in the early stage of post-collisional extension. Therefore, the southwestern Yangtze Block likely experienced a collision event during ca. 2.40–2.36 Ga, indicative of the involvement of the Yangtze Block in the ca. 2.5–2.3 Ga Arrowsmith orogeny of Laurentia. In addition, a series of accretionary events might also have occurred in the western Yangtze Block before the final assembly of the Columbia supercontinent, implying a tight spatial connection between the Yangtze Block and northwestern Laurentia within this global-scale supercontinent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cooperation in prisoner’s dilemma game can be promoted significantly by introducing memory effects. In this work, we assume that the changing probability of strategy is determined by the agents’ ...accumulative payoff in all time steps. We have numerically investigated robustness of cooperation by introducing an attack probability, with which an individual in cooperation clusters becomes a defector. It is found that the density of cooperators at stable states decreases with the attack probability in traditional memoryless models. However, in the memory-based model, the density of cooperators cannot reach a stable state even if the attack probability is very small. The more the increase of the attack probability, the faster the vanishment of the cooperators. Our work could be helpful to understand the emergence of cooperation in systems consisting of selfish individuals. It suggests a new method to study whether cooperation can be maintained in noisy environments.
•We introduce the accumulative payoff in all time steps.•Cooperation can be significantly promoted by introducing the accumulative payoff.•We introduce random defective mutations into cooperative clusters.•Robustness of cooperation is analyzed in such an invasive noise.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study manifested the effects of polysaccharides from Ganoderma lucidum strain S3 (GLP S3) on chronic pancreatitis (CP) therapy and intestinal microbiota modulation in mice induced by ...diethyldithiocarbamate (DDC). The GLPS3 was prepared from cultured mycelium and markedly alleviated the pancreatitis in mice through decreasing lipase, AMS, IFN-γ and TNF-α level as well as increasing SOD and total antioxidant activity. Furthermore, high throughput sequencing analysis revealed that GLPS3 altered the composition and diversity of intestinal microbiota, especially, decreased the relative abundance of phylum Bacteroidetes and increased that of phylum Firmictutes. At the genus level, supplementation of GLPS3 increased the relative abundance of the beneficial bacteria such as Lactobacillales, Roseburia and Lachnospiraceae. These results disclosed the potential therapy mechanism of GLPS3 on chronic pancreatitis might be intestinal microbiota dependent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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•1.18–1.14 Ga A-type monzogranites were identified in the SW Yangtze Block.•The A-type monzogranites formed by partial melting of ancient granitic sources.•Continental rifting took ...place extensively in the Yangtze Block at ca. 1.2–1.1 Ga.•The Yangtze Block was not yet part of the Rodinia in the late Mesoproterozoic.
The late Mesoproterozoic tectonic history of the Yangtze Block, South China in the context of the supercontinent cycles remains poorly understood due to the scarce preservation of geological records of this age. In this study, we report petrology, whole-rock geochemistry, zircon U-Pb ages and Hf-Nd isotopes for newly identified late Mesoproterozoic monzogranites from the southwestern Yangtze Block. SHRIMP and LA-ICP-MS zircon U-Pb dating results reveal that these monzogranites crystallized at ca. 1.18–1.14 Ga. All the studied samples possess typical geochemical signatures of A1-type granite, such as relatively high SiO2 (73.31–77.50 wt.%), Na2O + K2O (7.14–8.09 wt.%) and Zr + Nb + Ce + Y (362–445 ppm) contents, zircon saturation temperatures (825–851 °C), and low Y/Nb ratios (0.78–1.04). They have negative whole-rock εNd(t) values from −6.9 to −5.7 and zircon εHf(t) values from −7.4 to −2.5, with consistent Nd and Hf model ages of 2.4–2.1 Ga. The parental magmas for these monzogranites were generated by partial melting of the early Paleoproterozoic crustal materials at low pressure and high temperature. Taking into account of the coeval within-plate mafic magmatism in the southwestern Yangtze Block, these ca. 1.18–1.14 Ga A1-type monzogranites were most likely emplaced in a continental rift setting. Available data indicate continental rifting may have occurred extensively in the Yangtze Block at 1.2–1.1 Ga, followed by oceanic plate subduction starting at 1.1 Ga. We propose the Yangtze Block was an isolated plate during 1.2–1.1 Ga and started to drift toward the Rodinia supercontinent at ca. 1.1 Ga, favoring the proposal that a coherent supercontinent did not yet exist in the late Mesoproterozoic.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Infectious hematopoietic necrosis virus (IHNV) is an important pathogen that causes significant economic losses to salmon trout farming. Although vaccines have been invented for the treatment of ...IHNV, findings from our previous survey show that breeding enterprises and farmers require effective oral drugs or immune enhancers. However, studies on the development of oral drugs are limited. In the present study, we used bioinformatics methods to predict the protein targets of andrographolide (Andro) in IHNV. Cells were infected with IHNV, and the effect of andrographolide was explored by evaluating the expression levels of genes implicated in oxidative stress, activities of antioxidant enzymes, and the expression of genes implicated in apoptosis and necrosis. In the present study, cells were divided into NC, IHNV, IHNV+10 μM andrographolide, and IHNV+20 μM andrographolide groups. qRT-PCR was performed to determine the expression level of genes, and an antioxidant enzyme detection kit was used to evaluate the activities of antioxidant enzymes. Fluorescent staining was performed using a reactive oxygen species detection kit (ROS) and Hoechst 33342/PI double staining kit, and the mechanism of alleviation of apoptosis and oxidative stress andrographolide after IHNV infection was determined. The results indicated that andrographolide inhibits viral growth by binding to the NV protein of IHNV and increasing the antioxidant capacity of the body through the CTSK/BCL2/Cytc axis, thereby inhibiting the occurrence of IHNV-induced apoptosis. This is the first study to explore the antagonistic mechanism of action of andrographolide in alleviating IHNV infection. The results provide valuable information on alternative strategies for the treatment of IHNV infection during salmon family and provide a reference for the use of andrographolide as an antioxidant agent in agricultural settings.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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