Traditionally, the strata of the Luonie Valley, Dechang County, SW Sichuan, China, are considered to contain a suite of felsic volcanic rocks (the Huili Group) that erupted after c. 1050 Ma. However, we report here new age constraints, elemental and Lu–Hf isotope geochemistry for a different suite of older basaltic agglomerate lava, basaltic tuff lava and basalt from the same area, which we name the Luonie Formation. New dating results show that the basaltic volcanic suite of the upper part of the Luonie Formation formed at 1126.1 ± 9.9 Ma, significantly earlier than deposition of the Huili Group, but comparable in age to the 1142 ± 16 Ma Laowushan Formation in central Yunnan Province. Granite intrusion into the Luonie Formation dated 1050.7 ± 12.7 Ma provides crucial supporting evidence for this earlier depositional age. We also report a maximum sedimentary age of c. 1158 Ma for the underlying arkose, implying stratigraphic conformity with the basaltic volcanic rock suite.

The ϵHf(t) values of the basaltic volcanic rocks are mainly positive, indicating that the rocks are mainly derived from the depleted mantle and slightly stained by crustal materials. The characteristics of P*, Nb* and Zr* anomalies also support this view. The distribution patterns of trace and rare earth elements indicate that the basaltic volcanic rocks formed in an extensional setting. The Zr/4–Y–2Nb and Th–Nb/16–Zr/117 discrimination diagrams also provide evidence for this understanding. Lithofacies analysis shows that basaltic volcanic wrocks with the characteristics of both continental and marine facies should be formed in a littoral–neritic environment. We propose here that the evidence is consistent with a phase of continental extension that preceded the convergence of the SW Yangtze Block to form part of Rodinia.

Different kinds of waves and instabilities in the F-region of the ionosphere excited by the relative streaming of the dust beam to the background plasma are studied in the present paper. The dispersion relations of different waves are obtained on different time scales. It is found from our numerical results that there are both a stable upper hybrid wave on the electron vibration time scale and a stable dust ion cyclotron wave on the ion vibration time scale. However, the chaotic behaviour appears on the dust particles vibration time scale due to the relative streaming of the dust particles to the background plasma. Such instabilities may drive plasma irregularities that could affect radar backscatter from the clouds.

The complex sea ice conditions in Arctic waters has different impacts on the legs of the Arctic passage, and ships of specific ice classes face different navigation risks. Therefore, the quantitative analysis of the navigation risks faced in different legs has important practical significance. Based on the POLARIS introduced by IMO, the sea ice condition data from 2011 to 2020 was used to quantify the navigation risk of the Arctic Northeast passage. The risk index outcome (RIO) of the Arctic Northeast Passage were calculated. The navigable windows of the route for ice class 1A ships sailing independently under different sea ice conditions in the last decade were determined, with a navigable period of 91 days under normal sea ice conditions, approximately 175 days under light sea ice conditions and only week 40 close to navigation under severe sea ice conditions. The three critical waters affecting the safety of ships were identified. Combined with the navigable windows and critical waters, recommendations on ship's navigation and manipulation and recommendations for stakeholders were given. The method and results provided reference and support for the assessment of the navigation risk of ships in the Northeast Passage and safety navigation and operations of ships, and satisfied the needs of relevant countries and enterprises to rationally arrange shipment dates and sailing plans based on different ice classes of ships.

In this paper, we designed two different configurations with locally isothermal sidewalls, where the temperature is set to be the bulk temperature, to control the large-scale circulation in turbulent Rayleigh–Bénard convection, namely two-point control and four-point control. At fixed Rayleigh number $Ra=10^8$ and Prandtl number $Pr=2$, a series of direct numerical simulations are performed on both two-dimensional (2-D) and quasi-two-dimensional (quasi-2-D) cavities with both types of control, where the width of the control area is fixed at $\delta _c=0.05$ and the vertical distance from the cavity centre $h_c$ varies from 0 to 0.45 with an interval of 0.05. Our results show that the control effect depends on $h_c$, the control configurations as well as the flow dimensions. For 2-D cavities, both two-point control and four-point control suppress the flow reversal when $h_c \geq 0.05$, accompanied by the enhancement of vertical heat transfer and the strength of the large-scale circulation. For quasi-2-D cavities, the suppression of the flow reversals is obvious with two-point control and $h_c\geq 0.05$, while the effect is rather limited with four-point control. Further experiments with $Pr=5.7$ and $Ra$ up to $7.36\times10^8$ show that two-point control with $h_c=0.15$ can effectively suppress the flow reversal, while two-point control with $h_c=0$ can suppress the reversals at low $Ra=1.93\times 10^8$ and activate them at higher $Ra=7.36\times 10^8$, which agrees well with our numerical simulations.

We present an experimental study on controlling the number of vortices and the torque in a Taylor–Couette flow of water for Reynolds numbers from 660 to 1320. Different flow states are achieved in the annulus of width $d$ between the inner rotating and outer stationary cylinders through manipulating the initial height of the water annulus. We show that the torque exerted on the inner cylinder of the Taylor–Couette system can be reduced by up to 20 % by controlling the flow at a state where fewer than the nominal number of vortices develop between the cylinders. This flow state is achieved by starting the system with an initial water annulus height $h_0$ (which nominally corresponds to $h_0/d$ vortices), then gradually adding water into the annulus while the inner cylinder keeps rotating. During this filling process the flow topology is so persistent that the number of vortices does not increase; instead, the vortices are greatly stretched in the axial (vertical) direction. We show that this state with stretched vortices is sustainable until the vortices are stretched to around 2.05 times their nominal size. Our experiments reveal that by manipulating the initial height of the liquid annulus we are able to generate different flow states and demonstrate how the different flow states manifest themselves in global momentum transport.

The chase procedure for existential rules is an indispensable tool for several database applications, where its termination guarantees the decidability of these tasks. Most previous studies have focused on the skolem chase variant and its termination analysis. It is known that the restricted chase variant is a more powerful tool in termination analysis provided a database is given. But all-instance termination presents a challenge since the critical database and similar techniques do not work. In this paper, we develop a novel technique to characterize the activeness of all possible cycles of a certain length for the restricted chase, which leads to the formulation of a framework of parameterized classes of the finite restricted chase, called $k$-$\mathsf{safe}(\Phi)$ rule sets. This approach applies to any class of finite skolem chase identified with a condition of acyclicity. More generally, we show that the approach can be applied to the hierarchy of bounded rule sets previously only defined for the skolem chase. Experiments on a collection of ontologies from the web show the applicability of the proposed methods on real-world ontologies.

Dolostones are widely developed in the middle Permian rocks of East Yunnan, China, mainly in the shoal-facies Maokou Formation. The previously reported dolostone formation mechanisms cannot explain the distribution and geochemical characteristics of these dolostones, in particular their strontium, magnesium and oxygen isotope signatures. To help predict the distribution of dolostone reservoirs and reduce the exploration risk and cost, this study proposes a new model of dolomitization: open thermal convection dolomitization. In this new dolomitization model, Mg2+ in dolomitizing fluids originates mostly from seawater, with a minor component coming from deep hydrothermal fluids. Elevated heat flux (in this case due to the nearby Emei mantle plume) causes spatial temperature variations in the fluid along the circulation flow pathways, resulting in fast and pervasive dolomitization of limestone. The proposed model not only explains the characteristics and distribution of dolostones in the study area but also serves as a reference for predicting the distribution of dolostones in other areas subjected to thermal convection.

We find that corporate innovation is positively related to board diversity as measured by a multidimensional index. The benefit of board diversity is more pronounced for firms with more complex operations, more experienced boards, and stronger external governance, suggesting that diverse boards have superior advising capacity. We find evidence to suggest that firms with diverse boards engage in more exploratory innovations and develop new technology in unfamiliar areas. As a result, they create a larger number of both most-cited and uncited patents. Finally, of the six different aspects of board diversity, professional diversity matters the most for corporate innovation.

The mammary gland, a unique exocrine organ, is responsible for milk synthesis in mammals. Neonatal growth and health are predominantly determined by quality and quantity of milk production. Amino acids are crucial maternal nutrients that are the building blocks for milk protein and are potential energy sources for neonates. Recent advances made regarding the mammary gland further demonstrate that some functional amino acids also regulate milk protein and fat synthesis through distinct intracellular and extracellular pathways. In the present study, we discuss recent advances in the role of amino acids (especially branched-chain amino acids, methionine, arginine and lysine) in the regulation of milk synthesis. The present review also addresses the crucial questions of how amino acids are transported, sensed and transduced in the mammary gland.

The head-on collision between two dust-acoustic solitary waves in a non-magnetized, collisionless and strongly coupled dust plasma has been studied. The application scope of the analytical solution of the head-on collision is given in the present paper by using the particle-in-cell simulation method. It is noted that the analytical results are valid if the amplitudes of both of the solitary waves are small enough. The effects of the coupling parameters on both the head-on collision and the waveform are also studied in the present paper.

Compared with commercial polyolefin membranes, polyacrylonitrile (PAN) membrane prepared by electrostatic spinning has higher porosity, electrolyte uptake, thermal stability, and lithium-ion conductivity, etc. However, poor mechanical performance has largely limited the application of electrospun PAN separators. In this study, PAN/polyimide (PI) composite membrane is prepared by electrostatic spinning to improve the mechanical and electrochemical performances. Scanning electron microscopy, thermal analysis method, and electrochemical methods were used for evaluation of the electrospun composite membrane. The results show that the composite membrane possesses good thermal stability and exhibits better mechanical performance than pristine PAN membrane (increasing by 1.1 times in tension strength). The addition of PI can increase porosity and fluid absorption rate obviously. In addition, the composite membrane has high ionic conductivity (18.77 × 10−4 S/cm), wide electrochemical window (about 4.0 V), and excellent cycling performance. It can retain a discharge specific capacity of 153 mA h/g even after 50 cycles at 0.5 C. The electrospun PAN/PI membrane may be a promising candidate for lithium-ion battery separators.

The finite element simulations show that non-equibiaxial residual stresses (RS) can shift the load–depth curve from the unstressed curve and cause elliptical remnant indentation in spherical indentation. Thus the relative load change between stressed and unstressed samples and the asymmetry of elliptical remnant indentation were employed as characteristic parameters to evaluate the magnitude and directionality of RS. Through theoretical and numerical analysis, the effects of RS on indentation load and remnant impression as well as the affect mechanism were systematically discussed. Finally, two equations which could provide foundations for establishing spherical indentation method to evaluate non-equibiaxial RS were obtained.

We construct a growth model with status preference to explore the effects of patents on innovation and social welfare. We find a nonmonotonic effect of patent protection on innovation. Additionally, the growth-rate-maximizing degree of patent protection decreases when the strength of status preference is larger. The effect of patent protection on social welfare is ambiguous, depending on the strength of status preference. Moreover, wealth inequality widens as patent protection is reinforced. Finally, by using cross-section regression analysis, we document that a nonmonotonic relationship between patent protection and economic growth is statistically significant and that the growth-rate-maximizing degree of patent protection decreases with the strength of status preference.

We present experimental studies of higher-order modes of the flow in turbulent thermal convection in cells of aspect ratio ($\unicode[STIX]{x1D6E4}$) 1 and 0.5. The working fluid is water with the Prandtl number ($Pr$) kept at around 5.0. The Rayleigh number ($Ra$) ranges from $9\times 10^{8}$ to $6\times 10^{9}$ for $\unicode[STIX]{x1D6E4}=1$ and from $1.6\times 10^{10}$ to $7.2\times 10^{10}$ for $\unicode[STIX]{x1D6E4}=0.5$. We found that in $\unicode[STIX]{x1D6E4}=1$ cells, the first mode, which corresponds to the large-scale circulation (LSC), dominates the flow. The second mode (quadrupole mode), the third mode (sextupole mode) and the fourth mode (octupole mode) are very weak, on average these higher-order modes each contains less than 4 % of the total flow energy. In $\unicode[STIX]{x1D6E4}=0.5$ cells, the first mode is still the strongest but less dominant, the second mode becomes stronger which contains 13.7 % of the total flow energy and the third and the fourth modes are also stronger (containing 6.5 % and 1.1 % of the total flow energy respectively). It is found that during a reversal/cessation, the amplitude of the second mode and the remaining modes experiences a rapid increase followed by a decrease, which is opposite to the behaviour of the amplitude of the first mode – it decreases to almost zero then rebounds. In addition, it is found that during the cessation (reversal) of the LSC, the second mode dominates, containing 51.3 % (50.1 %) of the total flow energy, which reveals that the commonly called cessation event is not the cessation of the entire flow but only the cessation of the first mode (LSC). The experiment reveals that the second mode and the remaining higher-order modes play important roles in the dynamical process of the reversal/cessation of the LSC. We also show direct evidence that the first mode is more efficient for heat transfer. Furthermore, our study reveals that, during the cessation/reversal of the LSC, $Nu$ drops to its local minimum and the minimum of $Nu$ is ahead of the minimum of the amplitude of the LSC; and reversals can be distinguished from cessations in terms of global heat transport. A direct velocity measurement reveals the flow structure of the first- and higher-order modes.

Interleukin (IL)-13-associated signal pathway plays an important role in schistosomiasis hepatic fibrosis. In this study we tried to investigate the effects of corilagin to ameliorate schistosomiasis hepatic fibrosis through regulating IL-13-associated signal pathway in vitro and in vivo. Cellular model was set up with hepatic stellate cells-T6 cells stimulated by rIL-13 and male Balb/c mice were infected with Schistosoma japonicum cercariaeas as animal model. Liver histological changes were observed with haematoxylin and eosin staining. Masson staining was employed to observe the change of egg granulomas. Expression of Col (collagen) and Col III were examined with Immunohistochemistry. Western bolt was employed to detect the JAK-1 and IL13Rα1 proteins. The mRNA expression of Col I, Col III, IL-13, JAK-1 and IL13Rα1 were tested by quantitative polymerase chain reaction. As a result, less inflammatory changes were found in all corilagin groups compared with model group and praziquantel group. The mRNA levels of Col I, Col III, IL-13, JAK-1 and IL13Rα1 were significantly decreased after corilagin intervention (P < 0·01). JAK-1 and IL-13Rα1 protein levels were also greatly decreased in the corilagin groups (P < 0·01). In conclusion, corilagin could ameliorate schistosomiasis hepatic fibrosis by down-regulating the expression of IL-13 and signal molecules in IL-13 pathway.

Alkaline rock and carbonatite complexes, including the Prairie Lake complex (NW Ontario), are widely distributed in the Canadian region of the Midcontinent Rift in North America. It has been suggested that these complexes were emplaced during the main stage of rifting magmatism and are related to a mantle plume. The Prairie Lake complex is composed of carbonatite, ijolite and potassic nepheline syenite. Two samples of baddeleyite from the carbonatite yield U–Pb ages of 1157.2±2.3 and 1158.2±3.8 Ma, identical to the age of 1163.6±3.6 Ma obtained for baddeleyite from the ijolite. Apatite from the carbonatite yields the same U–Pb age of ~1160 Ma using TIMS, SIMS and laser ablation techniques. These ages indicate that the various rocks within the complex were synchronously emplaced at about 1160 Ma. The carbonatite, ijolite and syenite have identical Sr, Nd and Hf isotopic compositions with a 87Sr/86Sr ratio of ~0.70254, and positive εNd(t)1160 and εHf(t)1160 values of ~+3.5 and ~+4.6, respectively, indicating that the silicate and carbonatitic rocks are co-genetic and related by simple fractional crystallization from a magma derived from a weakly depleted mantle. These age determinations extend the period of magmatism in the Midcontinent Rift in the Lake Superior area to 1160 Ma, but do not indicate whether the magmatism is associated with passive continental rifting or the initial stages of plume-induced rifting.

Photometric data increase with large survey projects running. The huge volume of data influences the means and methods to deal with them. As such, the techniques of photometric redshift estimation based on photometric data must be developed and improved.

We probe many kinds of approaches used for photometric redshift estimation of quasars, including KNN (K-nearest neighbor algorithm), Lasso (Least Absolute Shrinkage and Selection Operator), PLS (Partial Least Square regression), ridge regression, SGD (Stochastic Gradient Descent) and Extra-Trees.