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Understanding the variation of geological interfaces plays a crucial role in the analysis and design of infrastructure systems. Generally, there are two classes of techniques for predicting geological interfaces, for example, interpolation/regression-based techniques and machine-learning-based techniques. In this paper, a Multi-scale Meta-learning Model (M3) methodology is proposed. The new methodology improves the current state-of-the-art techniques by fusing two levels of information: (i) generic characteristics of the sampling locations, for example, coordinates, and (ii) location-specific characteristics, for example, local-scale predictions. The implementation starts from using an array of classic interpolation/regression-based techniques as base learners to provide first-level predictions at a local scale. These predictions are then combined with generic characteristics to train a meta-learner following the stacking ensemble learning framework. In this manner, the location-specific information from the base learners can be simultaneously considered with the generic information in the training process. The variation of rockhead elevation is predicted using the M3 methodology and a comprehensive borehole dataset in Singapore. A detailed comparative study involving several existing methods is also carried out to rigorously validate the M3 methodology. The results show that the M3 methodology achieves 20% improvement in the model performance compared to existing methods, indicating its promising potential in geotechnical site characterization.

We report the first zinc isotope data (expressed as δ66Zn relative to the JMC-Lyon standard) for chromian spinels (Cr-spinels) and coexisting olivines in oceanic peridotites. All spinel-olivine pairs fall on the 1:1 fractionation line in the diagram of δ66Znspinel versus δ66Znolivine, suggesting equilibrium isotope fractionation. Cr-spinels are always isotopically lighter than coexisting olivines (Δ66Znspinel-olivine = δ66Znspinel − δ66Znolivine = −0.50‰ to −0.33‰; n = 13), which is opposite to the positive Zn isotope fractionation between Al-spinel and olivine observed in cratonic peridotites. The “inverse” Zn isotope fractionation between Cr-spinel and olivine is unlikely to have been caused by low-temperature alteration of the oceanic peridotites, given the lack of correlation between Δ66Znspinel-olivine values and chemical indices of serpentinization and weathering (e.g., LOIs, MgO/SiO2). Ionic model calculation indicates that even considering that Zn occurs at both tetrahedral and octahedral sites in the crystal lattice of spinel, the magnitude of equilibrium fractionation is still inconsistent with the observed Zn isotope fractionation between Cr-spinel and olivine. We suggest a “chemical effect” in which the Zn O bond length (tetrahedral site) in spinel increases when Cr substitutes Al in octahedral site, which is corroborated by the striking negative correlation of δ66Zn with Cr# [molar Cr3+/(Cr3+ + Al)] in natural spinels. Therefore, Zn isotopic compositions of natural spinels can be highly variable depending on their chemical compositions. During magma differentiation, zinc is moderately incompatible in silicate minerals (olivine and pyroxene) but highly compatible in Cr-spinels/chromites that have Zn contents tens of times higher than those of basaltic melts. Given its light Zn isotopic composition, chromite crystallization–if any–can evidently elevate δ66Zn and lower Zn contents of the residual melts. Lunar mare basalts are typically characterized by higher δ66Zn and lower Zn contents relative to terrestrial basalts, but modelling suggests that chromite crystallization during magmatic differentiation is unlikely to account for Zn isotopic and elemental data of lunar mare basalts. Global ocean island basalts (OIBs) and some intraplate alkali basalts have systematically higher δ66Zn and higher Zn contents than those of the normal mantle-derived melts (e.g., mid-ocean ridge basalts; MORBs), which contradicts with a chromite crystallization model. Instead, such signatures can reflect recycling of surface carbonates into the Earth’s deep mantle, reinforcing the application of zinc isotopes as a tracer of deep carbonate recycling.

The spatial variability of the properties of natural soils is one of the major sources of uncertainties that can influence the performance of geotechnical structures. The direct Monte-Carlo simulation (MCS) method, although robust and versatile, may incur prohibitively high computational burdens, especially for cases involving low failure probability levels. In this paper, a hybrid strategy that fuses convolutional neural networks (CNNs) and maximum entropy distribution with fractional moments (MaxEnt-FM) is proposed. MaxEnt-FM is a post-processing technique that fits a probability distribution to a set of sample data. The proposed hybrid strategy starts by training a CNN as the metamodel of the time-demanding random field finite element model. The trained CNN is then used to generate sample data, which is subsequently processed using the MaxEnt-FM technique to obtain failure probability. The use of a CNN allows MaxEnt-FM to be carried out without explicit calls to the finite element model. Therefore, the proposed hybrid strategy has the potential to provide a computationally efficient technique to calculate failure probability. For the illustrative slope stability example that has a failure probability of 3 × 10−4, the proposed hybrid strategy yields a less than 10% error in the predicted failure probability with only hundreds of finite element simulations.

Back analysis can provide engineers with important information for better decision-making. Over the years, research on back analysis has focused mainly on optimisation techniques, while comparative studies of data-interpretation methodologies have seldom been reported. This paper examines the use of three data-interpretation methodologies on the performance of geotechnical back analysis. In general, there are two types of approaches for interpreting model predictions using field measurements, deterministic versus population-based, both of which are considered in this study. The methodologies that are compared are (a) error-domain model falsification (EDMF), (b) Bayesian model updating and (c) residual minimisation. Back analyses of an excavation case history in Singapore using the three methodologies indicate that each has strengths and limitations. Residual minimisation, though easy to implement, shows limited capabilities of interpreting measurement data with large uncertainty errors. EDMF provides robustness against incomplete information of the correlation structure. This is achieved at the expense of precision, as EDMF yields wider confidence intervals of the identified parameter values and predicted quantities compared with Bayesian model updating. In this regard, a modified EDMF implementation is proposed, which can improve upon the limitations of the traditional EDMF method, thus enhancing the quality of the identification outcomes.

High-silica granites (typically > 70 wt.% SiO2) represent the products of extreme crustal differentiation, but whether their distinctive chemical compositions reflect source lithology or are produced via magmatic differentiation is commonly difficult to discriminate. To provide new insights into this issue, here we present high-precision Mg and Zn isotope data for high-silica, peraluminous leucogranites from the Himalayan orogen. The samples are subdivided into two-mica leucogranite, tourmaline leucogranite and garnet-bearing leucogranite based on their mineral assemblages. The two-mica leucogranites, representing the least evolved Himalayan leucogranites, have similar δ66ZnJMC 3-0749L (mean = 0.31 ± 0.06‰) but heavier δ26MgDSM-3 values (mean = −0.01 ± 0.12‰) relative to more mafic igneous rocks. This indicates that they were formed by anatexis of weathered silicates, consistent with the well-acknowledged metasedimentary source of the Himalayan leucogranites. In contrast, the more evolved tourmaline leucogranites and garnet-bearing leucogranites have lower δ26Mg and higher δ66Zn values compared with the two-mica leucogranites. The extremely low δ26Mg (−1.32‰ to −0.54‰) and high δ66Zn values (0.35–0.69‰) of garnet-bearing leucogranites vary systematically with indices of granitic differentiation (e.g., Zr/Hf, K/Rb, Eu/Eu*, 1/TiO2). Although exsolution of chlorine-rich fluid may result in elevated δ66Zn values, it is unlikely to explain the low δ26Mg signatures of the same samples. Analysis of major Mg-bearing minerals suggests that substantial segregation of tourmaline and/or Fe-Ti oxide could have driven the differentiated leucogranites towards very low δ26Mg values. In this regard, the slightly lower δ26Mg values (mean = −0.17 ± 0.06‰) of tourmaline leucogranites relative to the two-mica leucogranites may also reflect that the former were more differentiated than the latter. Thus, although source heterogeneity may be responsible for the Mg isotopic variations observed in some high-silica granites, our study implies that high-silica granites could be remarkably heterogeneous in terms of Mg isotopes primarily as a result of prolonged fractional crystallization at the late stage of melt evolution. The anomalously light Mg and heavy Zn isotopic signatures of garnet-bearing leucogranites highlight that Mg and Zn isotopes may be treated as important makers of highly fractionated granites in future studies.

The behaviours of Cu, Zn and their isotopes during seafloor fluid-peridotite interaction and its influence on oceanic Cu-Zn cycles were investigated by analyzing a series of unaltered to strongly altered oceanic peridotites. Most of the altered peridotites have δ66Zn values indistinguishable from those of the unaltered ones (0.19 ± 0.05‰; 2SD), suggesting that seafloor alteration generally induces a small Zn isotope fractionation. A few altered samples that seem to have gained Zn have elevated δ66Zn, probably due to adsorption by ubiquitous secondary phases (e.g. goethite). Almost all altered peridotites show Cu loss (up to 90%) and have Cu isotope ratios that are shifted toward heavy values relative to the unaltered ones. Given that Cu is organically-complexed in fluids over a wide range of temperature and such fluids have strong preferences for the heavy isotopes, alteration and weathering alone are unlikely to account for the substantial loss of Cu coupled with elevated δ65Cu. An alternative mechanism is that initial Cu in peridotites was partly lost by alteration and weathering, and then Cu was added via adsorption by secondary mineral phases preferring the heavy Cu isotopes. This is confirmed by leaching experiments that were designed to extract the adsorbed Cu fractions in secondary phases. The results show that the leachates and the residua have, respectively, higher and lower δ65Cu values in comparison with the bulk peridotites, demonstrating that adsorption is an important mechanism for generating heavy copper isotope enrichments in the altered peridotites. In any case, mass balance considerations indicate that oceanic alteration must have resulted in a net input of isotopically light Cu from oceanic peridotites into the ocean. Recent estimates found that the Cu isotopic composition of the modern ocean is imbalanced, because all characterized sinks are isotopically light relative to characterized input fluxes, which requires an additional, isotopically light input. Our results indicate that seafloor alteration of abyssal peridotites is an isotopically light input (δ65Cu = −0.4‰ to −0.1‰) to the modern ocean, up to ∼1‰ lighter than the riverine input (∼0.7‰). First-order flux estimates suggest that this process exerts an important control on the marine budget of Cu. Most of Zn released during seafloor alteration has δ66Zn similar to that of mantle peridotites and this input is thus slightly lighter than the riverine input (∼0.33‰). Current estimates of modern oceanic Zn isotope cycles require consideration of this isotopically light source.

In the literature, the plane-strain assumption usually forms the basis of inverse analyses of excavations, mainly due to the high computational cost of 3D analyses. In this paper, a procedure that quantifies three-dimensional effects of excavation is proposed. Such three-dimensional effects are represented as an uncertainty term that corrects plane-strain-based predictions, thereby offering an alternative approach to perform 3D inverse analysis without excessive computations. The results of an inverse analysis performed on an excavation case history show that (i) the procedure is able to quantify three-dimensional effects reasonably well and (ii) improved predictions of excavation field responses can be obtained.

Some high silica granitic rocks (SiO2 > 70 wt%) show larger Zn isotopic variations (δ66ZnJMC 3-0749L) than less silicic granitic rocks, for which the reasons are unclear. Here we report Zn isotopic data for leucosomes (L, melt) and melanosomes phases (M, residue) in migmatites as well as granitoids from the Dabie orogenic belt, central China. Leucosomes always have higher δ66Zn than their associated melanosomes, with Δ66ZnL–M (δ66ZnL – δ66ZnM) varying widely from 0.08‰ ± 0.07‰ to 0.76‰ ± 0.07‰. High (Th/U)L/M ( Th / U leucosome Th / U melanosome ) ratios of four migmatite samples indicate modification of the leucosomes by fluid exsolution. Rayleigh fractionation modeling suggests that fluid exsolution could be responsible for the elevated δ66Zn in the four leucosomes. Three samples with large Δ66ZnL–M values and positive Eu anomalie, also have high Δ66ZnL-M values, probably due to accumulation of isotopically heavy plagioclase. Equilibrium Zn isotopic fractionation caused by partial melting is modeled to be 0.14‰–0.18‰ (Δ66Znmelt–residual) at 704–820 °C, consistent with the measured diatexite data (Δ66ZnL-M = 0.14‰ ± 0.07‰). The remaining two samples that were not significantly affected by fluid exsolution or plagioclase accumulation yield Δ66ZnL-M values larger than those expected in equilibrium melting and may reflect disequilibrium fractionation between melt and residue during the rapid melt segregation from the source. Our study confirms that Zn isotopes could be significantly fractionated during crustal anatexis and the magnitude of fractionation can be further enhanced by late-stage magmatic differentiation. Therefore, zinc isotope may act as a potential indicator of crust differentiation.

Intraplate basaltic volcanism commonly exhibits wide compositional ranges from silica-undersaturated alkaline basalts to silica-saturated tholeiitic basalts. Possible mechanisms for the compositional transition involve variable degrees of partial melting of a same source, decompression melting at different mantle depths (so-called ‘lid effect’), and melt-peridotite interaction. To discriminate between these mechanisms, here we investigated major-trace elemental and Sr–Nd–Mg–Zn isotopic compositions of a suite of intraplate alkaline and tholeiitic basalts from the Datong volcanic field in eastern China. Specifically, we employed Mg and Zn isotope systematics to assess whether the silica-undersaturated melts originated from a carbonated mantle source. The alkaline basalts have young HIMU-like Sr and Nd isotopic compositions, lower δ26Mg (-0·42‰ to -0·38‰) and higher δ66Zn (0·40‰ to 0·46‰) values relative to the mantle. These characteristics were attributable to an asthenospheric mantle source hybridized by carbonated melts derived from the stagnant Pacific slab in the mantle transition zone. From alkaline to tholeiitic basalts, δ26Mg gradually increases from -0·42‰ to -0·28‰ and δ66Zn decreases from 0·46‰ to 0·28‰ with decreasing alkalinity and incompatible trace element abundances (e.g. Rb, Nb, Th and Zr). The Mg and Zn isotopic variations are significantly beyond the magnitude (

In recent years, the random field finite-element method (FEM) has been used increasingly in geotechnical engineering to carry out analyses that account for the inherent spatial variability ...

The three-phase four-leg inverter can effectively solve the problem of asymmetric output waveform when the system is equipped with unbalanced and nonlinear loads. A mathematical model of the inverter can be established in a rotating coordinate system, and proposing a control strategy based on improved repetitive control. By decoupling the four-leg inverter into three single-phase inverters, closed-loop control of positive and negative zero-sequence components is achieved, ensuring the accuracy and dynamic stability of the system. A simulation using Simulink is designed on this technology and presented to verify the correctness and feasibility of the method. System using the method proposed in this paper has high output waveform quality under unbalanced, nonlinear, and sudden load changes. At the same time, it has strong unbalanced load capacity, good dynamic and static performance, and meets the requirements of industrial design.

How distributed power access distribution networks bring the greatest benefits is closely related to the optimal configuration of distributed power supplies. This paper studies the grid-connected planning problem of DG, establishes the distribution network of DG model with the least active loss, power generation and power purchase cost as the objective function, and uses the improved hybrid particle swarm optimization (PSO) algorithm to access the distributed power supply for distribution network. The algorithm is based on the traditional particle swarm optimization algorithm and adopts the strategy of inertia weight adjustment based on dispersion, adjusts the weight according to the population environment information, and introduces the elite aging mechanism and replacement mechanism to apply the dual-population co-evolution. The strategy allows information between the various groups to be shared, so that the genetic and particle populations co-evolve in the process of optimization. However, by analyzing to the IEEE33 standard node power distribution system, the results show that the reasonable configuration of DG can effectively reduce the network loss and cost, and the proposed model and algorithm are reasonable and feasible.

The soft pack power battery’s lug is prone to welding through and missing welding during the welding process due to its low flatness. A welding track detection system for the soft-pack power battery tabs is designed to solve the soft-pack power battery tabs’ welding difficulties. The system uses a laser sensor to perform non-contact detection on the welding surface of the tab. The system uses a laser sensor to perform non-contact detection on the welding surface of the lug. Then filter the collected data, and perform a non-uniform B-spline curve-fitting on the processed data to generate a welding track curve. Finally, welding the tabs according to the welding track curve can improve the tabs’ welding quality. The experimental results show that the average deviation between the fitted curve and the measured data points is 0.0817 mm, which has a good fitting effect and high calculation accuracy. It can be used on other occasions where this function is needed.

Excavation is a complex multistage problem, where field responses of soil properties such as deflections at one stage of the operation depend on responses at the preceding stage. In order to help asset managers make better decisions and thus improve safety, soil properties should be accurately identified using sensor-data collected at the current stage. This task is not easy to accomplish, mainly because of its intrinsic ambiguity. Sensors usually only measure effects (e.g., field responses) but not causes (e.g., soil parameter values). A strategy that helps meet this challenge is to perform inverse analysis to validate soil parameter values. Error-Domain Model Falsification (EDMF) is a methodology that achieves this goal. More precisely, EDMF helps identify good behavior models of excavation by falsifying soil parameter values for which the predictions of the corresponding behavior models cannot explain field-response measurements collected by sensors. However, a remaining challenge is the identification of soil parameter values that are not falsified by EDMF, especially when the computation of the predictions is time-consuming. This paper proposes a new framework that combines EDMF and an optimization algorithm for efficient identification of soil parameter values. Results on a full-scale excavation site in Singapore show that the new framework is robust and accurate, and it has the potential to improve current practice, which relies primarily on surrogate models without uncertainty.

In order to develop a secure and competent technique to express the human immune gene for fighting infections, we cloned and expressed the BD2/3 using VR1020 (a eukaryotic expression plasmid). BD2/3 contains human β-defensin 2 (BD2) and human BD3. To explore safe and effective DNA delivery molecules in vitro and in vivo, the fusion genes of BD2/3 were used as an immune-labelled gene to verify transfection effectivness of modified chitosan (CS). Plasmid of VR1020-BD2/3 was packed with biomaterials: CS, average molecular weight: 25000D; polyethylene glycol-O-chitosan-polyethylenimine (PEG-O-CS-PEI); liposomes (LP); polyamine cationic liposomes (PCL); polyamine cationic liposomes of protamine (PCL-protamine) by ionotropic gelation. We observed that BD2/3 fusion gene showed high bioactivity in vitro and in vivo. The BD2/3 fusion protein inhibited the proliferation of bacteria (S. aureus, S. pneumoniae, P. aeruginosa and E. coli). The Kunming mice were immune to these nanoparticles and we analyzed their delivery efficiency and gene expression effect. BD2/3 results in multiple changes of innate and required immune system of mice. BD2/3 increases expression of IgG, IgG1, IgG2a, IL-2, IL-6, IFN-γ, as well as of lymphocytes and monocytes. Following challenge with virulent E. coli, CD4+ and CD8+ positive T-cell counts were highly elevated in the BD2/3 immunized mice, resulting in higher survival rates of mice. These results indicate that nanoparticles containing modified CS and BD2/3 are potentially safe and effective drugs in vivo to improve the immunity against bacterial infection and enhance innate immunity and adaptive immunity against infectious diseases.

Highlights • Knockdown of TGF-β1 gene expression by shRNA inhibited PRRSV replication in pig immune cells and increased the viability of infected cells. • Silencing TGF-β1 gene expression by shRNA enhanced the antiviral immunity and reduced PRRSV yield in the infected cells. • Silence of TGF-β1 gene expression by shRNA can facilitate the control of PRRSV infection in pigs., Transforming growth factor beta 1 (TGF-β1) was of importance in the pathogenesis of porcine reproductive and respiratory syndrome virus (PRRSV). To determine whether knockdown of TGF-β1 gene expression could facilitate the control of PRRSV infection, specific sequences for expressing shRNA targeted to porcine TGF-β1 gene were synthesized and cloned into pSilencer 3.1-H1 neovector. Then they were used to transfect peripheral blood mononuclear cells of Tibetan pig (Tp-PBMCs) followed by PRRSV inoculation. The positive recombinant plasmids were screened for inhibition of TGF-β1 gene expression by real-time quantitative RT-PCR. Conversely, the mRNA level of PRRSV in shRNA treated Tp-PBMCs dramatically decreased, and there were significant increases of the transcription of immune genes, such as interleukin-2 (IL-2), interleukin-4 (IL-4), interferon-alpha (IFN-α), interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), toll-like receptor 3 (TLR3), toll-like receptor 7 (TLR7), Myeloid differentiation primary response gene (88) (MyD88), and interleukin-27p28 (IL-27p28). However, the expressions of IL-8 and IL-10 genes significantly reduced in comparison to the control infected cells. In addition, transfection with the shRNA plasmids significantly elevated the viability of immune cells. Therefore the knockdown of TGF-β1 gene expression by shRNA not only inhibits the replication of PRRSV but also improves immune responsiveness following viral infection, suggesting a novel way to facilitate the control of PRRSV infection in pigs.

The zinc (Zn) stable isotope system has great potential for tracing planetary formation and differentiation processes due to its chalcophile, lithophile and moderately volatile character. As an initial approach, the terrestrial mantle, and by inference, the bulk silicate Earth (BSE), have previously been suggested to have an average δ 66 Zn value of ∼+0.28‰ (relative to JMC 3-0749L) primarily based on oceanic basalts. Nevertheless, data for mantle peridotites are relatively scarce and it remains unclear whether Zn isotopes are fractionated during mantle melting. To address this issue, we report high-precision (±0.04‰; 2SD) Zn isotope data for well-characterized peridotites ( n = 47) from cratonic and orogenic settings, as well as their mineral separates. Basalts including mid-ocean ridge basalts (MORB) and ocean island basalts (OIB) were also measured to avoid inter-laboratory bias. The MORB analyzed have homogeneous δ 66 Zn values of +0.28 ± 0.03‰ (here and throughout the text, errors are given as 2SD), similar to those of OIB obtained in this study and in the literature (+0.31 ± 0.09‰). Excluding the metasomatized peridotites that exhibit a wide δ 66 Zn range of −0.44‰ to +0.42‰, the non-metasomatized peridotites have relatively uniform δ 66 Zn value of +0.18 ± 0.06‰, which is lighter than both MORB and OIB. This difference suggests a small but detectable Zn isotope fractionation (∼0.1‰) during mantle partial melting. The magnitude of inter-mineral fractionation between olivine and pyroxene is, on average, close to zero, but spinels are always isotopically heavier than coexisting olivines (Δ 66 Zn Spl-Ol = +0.12 ± 0.07‰) due to the stiffer Zn-O bonds in spinel than silicate minerals (Ol, Opx and Cpx). Zinc concentrations in spinels are 11–88 times higher than those in silicate minerals, and our modelling suggests that spinel consumption during mantle melting plays a key role in generating high Zn concentrations and heavy Zn isotopic compositions of MORB. Therefore, preferential melting of spinel in the peridotites may account for the Zn isotopic difference between spinel peridotites and basalts. By contrast, the absence of Zn isotope fractionation between silicate minerals suggests that Zn isotopes are not significantly fractionated during partial melting of spinel-free garnet-facies mantle. If the studied non-metasomatized peridotites represent the refractory upper mantle, mass balance calculation shows that the depleted MORB mantle (DMM) has a δ 66 Zn value of +0.20 ± 0.05‰ (2SD), which is lighter than the primitive upper mantle (PUM) estimated in previous studies (+0.28 ± 0.05‰, 2SD, Chen et al., 2013b; +0.30 ± 0.07‰, 2SD, Doucet et al., 2016). This indicates that the Earth’s upper mantle has a heterogeneous Zn isotopic composition vertically, which is probably due to shallow mantle melting processes.

Carbon in the form of carbonate in sediments and altered oceanic crust can be transported into the mantle by subducted slabs, but how to identify recycled carbonate and decipher its storage depths in the mantle still requires to be investigated for typical subduction zones. Here we investigate possible carbonate recycling related to subduction of the Neo-Tethyan oceanic slab, by a combined study of Mg and Zn isotopes on three types of Cenozoic mantle-derived lavas from central Myanmar. The calc-alkaline lavas have arc-like geochemical characteristics and originated from the mantle wedge. These rocks have high δ26Mg (−0.20‰ to +0.03‰), interpreted to be caused by the input of Mg-rich fluids from dehydration of altered subducted slab. The alkali basalts of suite I are depleted in Nb and Ta and were derived from partial melting of the lithospheric mantle, which have normal δ26Mg and δ66Zn. By contrast, the alkali basalts of suite II display OIB-like trace element patterns and originated from the asthenospheric mantle. They possess extremely low δ26Mg (−0.66‰ to −0.48‰) and high δ66Zn (0.57‰ to 0.77‰) that is typically characterized by marine carbonates. No known processes (e.g., magmatic processes and diffusion effects) can account for the coupling of low δ26Mg and high δ66Zn except source heterogeneity caused by recycled magnesian carbonates (magnesite ± dolomite). This is supported by Mg-Zn-Sr isotopic mixing modelling that suggests a “magnesian carbonate + pyroxenite” source. Since calcic carbonate transforms to magnesite at depths of >300 km during subduction, carbonates carried by the Neo-Tethyan oceanic slab may have been recycled into the mantle transition zone as revealed by seismic tomography observations on central Myanmar.

The random field finite element method (RF-FEM) provides a robust tool for carrying out slope reliability analysis that incorporates the spatial variability of soil properties. However, it has a major drawback of being computationally very time-consuming. To address this common criticism, the current study proposes a novel metamodel-based method for efficient slope reliability analysis in spatially variable soils. The proposed method involves the use of Convolutional Neural Networks (CNNs) as metamodels of the random field finite element model. With proper training using a small but sufficient number of random field samples, the CNN can potentially replace the computationally demanding random field finite element analyses for Monte-Carlo simulations. This paper examines the capability of CNNs to learn high-level features that contain information about the random variabilities in both spatial distribution and intensity, and the accuracy of the subsequent predictions of the RF-FEM results. Application of the proposed method to slope reliability analysis in spatially variable soils is illustrated and compared against other metamodel-based approaches, using a case study involving a multi-layered soil system with randomly varying cohesion c and the friction angle ϕ. The results show that (i) the proposed CNN approach predicts a probability of slope failure that is within 5% of the corresponding value obtained using direct RF-FEM Monte-Carlo simulations, but at a small fraction of the computational cost, and (ii) the proposed method also compares favourably against other metamodel-based methods in terms of computational efficiency and accuracy.

Available data in the literature have demonstrated a broad magnesium (Mg) isotope range for mantle and lower continental crustal rocks, implying an isotopically heterogeneous continental lithosphere, but its origin has not been thoroughly understood. Here, to investigate the primary cause of lithospheric Mg isotopic heterogeneity, we report major-trace elements, Sr and Mg isotope data for thirty deep-seated mafic xenoliths, which sampled different lithospheric depths in the southeastern North China Craton (NCC). The xenoliths are classified into three types based upon petrology and mineralogy, sampling from middle continental crust (Group I), lower continental crust (Group II) and lithospheric mantle (Group III), respectively. The Group I xenoliths have mantle-like to slightly high δ26Mg values ( − 0.32 ‰ to + 0.01 ‰ ), whereas some of the Group II xenoliths have very low δ26Mg values ( − 0.93 ‰ to − 0.07 ‰ ), reflecting substantial reaction with intracrustal carbonate-derived fluids. Combined with data in the literature, the results suggest that the Mg isotopic composition of the lower continental crust is much more heterogeneous and lighter on average relative to the middle continental crust. Except for one sample, the Group III xenoliths have extremely low δ26Mg values ( − 1.23 ‰ to − 0.73 ‰ ), the lightest among values already reported for mantle-derived rocks including peridotites and basalts. They also have highly variable 87Sr/86Sr ratios, of 0.70387 to 0.71675. The covariation of Mg and Sr isotopes in Group III xenoliths can be explained by Mg and Sr isotopic exchange reactions during mantle metasomatism, implying that the sub-continental mantle has been significantly modified by fluids derived from recycled carbonate-pelite bearing oceanic crust. Together with the metasomatism age of ∼400 Ma obtained for one Group III xenolith, the results provide new evidence for the presence of extremely low-δ26Mg rocks in the lithosphere and indicate ancient carbonate recycling during Paleo-Tethys slab subduction. Experimental and computational studies have demonstrated that the solubility of carbonate in aqueous fluids increases with increasing pressures. Therefore, we suggest that the decreasing δ26Mg values of mantle-derived rocks with increasing depths across cratonic lithosphere, as found in the NCC and other regions, have probably been caused by carbonate metasomatism to various extents at different lithospheric depths.

A large set of zinc (Zn) stable isotope data for continental basalts from eastern China were reported to investigate the application of Zn isotopes as a new tracer of deep carbonate cycling. All of the basalts with ages of 120 Ma basalts from eastern China (0.27±0.06‰0.27±0.06‰; 2sd). Given that Zn isotope fractionation during magmatic differentiation is limited (≤0.1‰), the elevated δ66Zn values reflect the involvement of isotopically heavy crustal materials (e.g., carbonates with an average δ66Zn of ∼0.91‰) in the mantle sources. SiO2 contents of the

To develop a cost-effective molecular regulator to improve growth metabolism and immunity of animals, a recombinant plasmid co-expressing fatty acid desaturase (mFat-1) and pig insulin growth like factor 1 (IGF-1) genes was constructed by the 2 A self-cleavage technique. After entrapment within modified chitosan nanoparticles (chitosan modified with polyethyleneglycol–polyethylenimine, CPP), the recombinant plasmid was injected intramuscularly into mice. Compared with controls, co-expression of mFat-1 and IGF-1 significantly raised the level of serum IGF-1, and increased the liver and muscle docosa hexaenoic acid (DHA) content. Th and Tc cell levels were also elevated, as were expression levels of serum IL-4 and IL-6 genes. These results demonstrate that the immunity and metabolism of an animal can be effectively improved by co-expression of mFat-1 and IGF-1 genes in vivo, which may contribute to further development of novel immunomodulators with beneficial effects on growth metabolism and immunity.

IL-15 cDNA of Tibetan pig was firstly cloned from its activated lymphocytes, and then was sub-cloned into VR1020 to construct recombinant VRTIL-15 plasmid to study the in vitro and in vivo biological effects on animal. The VRTIL-15 was entrapped with chitosan modified with PEG-PEI (CS-PEG-PEI) to transfect HEK293 cells for the preliminary study of its expression in eukaryotic cells. The total RNA of HEK293 cell was isolated in 48h, and the successful expression of IL-15 was detected by RT-PCR and the supernatant of HEK293 cells was found to stimulate significant proliferation of lymphoblasts of pig. Subsequently, VRTIL-15 packed with CS-PEG-PEI was utilized to intramuscularly inoculate Kunming female mice at the age of 21 days. Their bloods were collected before and after inoculation on 1, 2, 3, 4 and 5 weeks to detect the changes of innate and adaptive immunity of animals. The results were found that Th and Tc, specific antibody to FMD, IgG, IgG1, IgG2a content markedly increased in the blood of treated mice compared with the control group (P

Increase of interleukin-10 (IL-10) induced by Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) infection has been intensely studied to inhibit the anti-viral responses of host pigs. Blockade of expression of IL-10 receptor (IL-10R) by RNA interference (RNAi) may relieve the immunosuppression caused by excessive IL-10 in PRRSV infection. The recombinant short hairpin expressing plasmid targeted to pig IL-10Rα was transfected into peripheral blood mononuclear cells of Tibetan pig (Tp-PBMCs) prior to PRRSV inoculation, then the replication of PRRSV and immune responses in Tp-PBMCs were evaluated. The recombinant interfering plasmid greatly decreased PRRSV yield. The transcriptional level of IL-10Rαwas obviously inhibited by recombinant interfering plasmid; the expression of IL-10 was also down-regulated, while that of TGF-β1 was not affected. Furthermore, the recombinant plasmid notably up-regulated the mRNA levels of TLR3, TLR7, IFN-α, IFN-γ, IL-2, IL-4, IL-12p40 and MyD88, while that of IL-8 was apparently decreased; In addition, cell viability of Tp-PBMCs was clearly enhanced by the interfering recombinant plasmid. Our results suggest that knockdown the expression of pig IL-10Rα can evidently inhibit the PRRSV infection and enhance the anti-viral immune responses of pig immune cells, which may be a promising way for preventing virus infection and developing new effective immune-regulator to strengthen the host immunity against PRRS.

The novel reco mbinant euka ryotic VRPIL4/ 6 p lasmid, the secretory VR1020 vector containing fused pig IL-6 and IL-4 genes, was encapsulated with chitosan nanoparticles (CNP) prepared by use of ionotropic gelat ion method and then used to inoculate intramuscularly forty 14-day-old piglets using 0.5, 1.0 or 1.5mg/per anima l, which were simu ltaneously injected with inactivated Mycoplasma hyopneumoniae vaccine and challenged on 10 weeks post vaccination, which were designated as group A1, A2 and A3. Blood was collected every two weeks fro m the piglets after vaccination to detect the changes in immunoglobulin, specific antibod y, IL-2, IL-4, IL-6, IFN-γ and immune ce lls. Co mpared to the control piglets with VR1020-CNP, the concentration of Ig G, IgA and IgM, specific antibody, interleukins and IFN-γ significantly increased in the sera of the groups treated with the fusion genes fro m 14 to 70 days after vaccination (P0.05 or P