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ABSTRACT: This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and jejunum during embryogenesis in Muscovy ducks. The weights of embryos and yolk sac (YS) (5 embryos per replicate, n = 6) were recorded on embryonic days (E)16, E19, E22, E25, E28, E31, and the day of hatch (DOH). The fat and fatty acid contents in YSM, jejunal histology, and gene expression related to fatty acid metabolism in YSM and jejunum were determined in each sampling time. Among the nonlinear models, the maximum growth is estimated at 2.83 (E22.5), 2.67 (E22.1), and 2.60 (E21.3) g/d using logistic, Gompertz, and Von Bertalanffy models, respectively. The weight of YS, and ether extract-free YS as well as the amounts of fat and fatty acids in YS decreased (P < 0.05) linearly, whereas the villus height, crypt depth, villus height/crypt depth, and musculature thickness in jejunum increased (P < 0.05) linearly during embryogenesis. The mRNA expression of CD36, SLC27A4, and FABP1 related to fatty acid uptake as well as the mRNA and protein expressions of PPARα and CPT1 related to fatty acid oxidation increased in a quadratic manner (P < 0.05) in both YS and jejunum, and the maximum values were achieved during E25 to E28. In conclusion, the maximum growth rate of Muscovy duck embryos was estimated at 2.60 to 2.83 g/d on E21.3 to E23.5, while the accumulations of lipid and fatty acid in YS were decreased in association with the increased absorptive area of morphological structures in jejunum. The gene and protein expression involved in fatty acid metabolism displayed a similar enhancement pattern between YSM and jejunum during E25 to E28, suggesting that fatty acid utilization could be strengthened to meet the energy demand for embryonic development.

Microgrids comprising photovoltaic (PV), energy-storage systems and electric vehicles have received increasing attention. However, the increase in renewable energy sources, such as PVs, will introduce uncertainty factors to the frequency response, resulting in frequency fluctuations that can reduce power quality. Hence, we propose an outstanding learning-based control approach that combines a model of physical principles with a Gaussian Process (GP) learning approach. The learning model corrects the physical principles model and estimates its uncertainty. Simulations are performed by comparing the proposed controller with conventional model-predictive controllers. The results indicate that the learning-based controller proposed can adjust the frequency with less overshooting and a lower root mean square error compared to the conventional MPC control method.

Slit fin-and-tube heat exchangers are extensively utilized in industry. The design of fin structure is crucial for improving the performance of heat exchanger and reducing energy losses. In this study, a new type of fin-and-tube heat exchanger with trapezoidal slit fins was proposed in this study. To determine the performance of the fins, physical and mathematical models of heat exchanger with the fin spacing Fp of 2.65 mm were established. The effects of structural parameters on heat exchanger performance were investigated by numerical simulation, which includes the slit height Sh, slit width Sw, transverse tube spacing Pt, and longitudinal tube spacing Pl. The effects of the four structural parameters on the comprehensive performance were analyzed by the evaluation index. The results revealed that the comprehensive performance of trapezoidal slit fins had increased by 9.6 % compared to flat fins. Furthermore, the influence degree of structural parameters on heat transfer performance was obtained based through the orthogonal experiments. The order of influence degree was as follows: Pl > Pt > Sh > Sw. Additionally, the optimal parameter combination was also obtained as follows: Sh = 1.47 mm, Pt = 42 mm, Pl = 27.5 mm, and Sw = 4 mm.

This study reveals the dynamic compressive deformation anisotropy among 316L stainless steel fabricated via wire and arc additive manufacturing process(WAAM). Cylindrical samples extracted from as-built WAAM 316L plate with 35°, 45°, 55°and 90° from scanning direction, were referred to as , , and crystallographic orientations hereinafter, which had been confirmed through backscattered diffraction. Cylindrical samples were subjected to dynamic tests by a split Hopkinson pressure bar. The corresponding mechanical behaviors and deformed microstructures are associated. There are approximately 10% higher dynamic flow stresses from the samples than other samples during dynamic tests at strain rates less than 3500 s−1, which can be attributed to lower density of thinner deformation twins. The lower tendency towards deformation twinning in samples arises from the increase of effective stacking fault energy. WAAM 316L presents an anisotropy of resistance to adiabatic shearing, of which the order is , , and . Two adiabatic shear bands(ASB) in sample present distinct orientation characters, where the sub-grains in the first ASB show and -fiber while that in the subsequent one take -fiber. This micro-texture discrepancy from two ASBs could be contributed to the precondition change of macro texture in the matrix which give birth to.

Ischemic stroke is one of the leading causes of disability and mortality. The collaterals provide an alternative pathway to preserve the ischemic brain tissue, and determine the penumbra range, where the neurons are salvageable. Therefore, accurately monitoring the collaterals and identifying the penumbra are crucial. Herein, a low-immunogenic nanoprobe-based MRI strategy is developed to simultaneously identify the infarct core, collaterals distribution, and ischemic penumbra distributions. The low-immunogenic nanoprobe was constructed by covalently attaching self-peptide on the surface of biocompatible Fe3O4 nanoparticles as a stealth coating. Both in vitro and in vivo experiments clearly revealed that the nanoprobes can effectively avoid capture by macrophages, and exhibited prolonged blood half-life to continuously enhance the contrast of blood vessels in a longer time window in susceptibility-weighted imaging (SWI), which enabled the delineation of the collaterals and ischemic penumbra. More importantly, combined with the diffusion-weighted imaging (DWI), the infarct core, collateral vessels, and the ischemic penumbra range can be identified simultaneously. In this context, the stroke progress including infarct core growth, collateral vessel formation, and penumbra distribution, can be better understood. This nanoprobe-based strategy thus offers a practical route for precise diagnosis of ischemic stroke, which remains a challenge for conventional MRI strategies.

Background: Hepatocellular carcinoma (HCC), a malignancy with high mortality and recurrence rates, has very limited options for treatment strategies. Dehydrocostus lactone (DL) is the principal quality marker extracted from Aucklandia lappa Decne. and has been demonstrated to possess excellent anticancer activity. The key purpose of this study was to explore the therapeutic effects and potential mechanisms of DL on HCC. Methods: The effect of DL on the cell viability of HCC cell lines (HepG2 and SK-HEP-1) and normal human hepatocyte cell line (L-O2) was examined by CCK8, colony formation, and BeyoClickTMEdU-488 assays; Hoechst 33,258 staining and flow cytometry were utilized to determine the impact of DL on apoptosis; the sensitivity of HCC cells to DL was explored by adding Z-VAD-fmk. In addition, the expression of apoptosis-related proteins Bax, Bcl-2, and PARP was detected by western blotting; the expression of p-H2AX was investigated by western blotting and immunofluorescence staining; cell cycle distribution was observed using flow cytometry; the migration ability and invasiveness of HCC cells were assessed by wound healing assay and transwell assay; immunoblotting was applied to visualize the levels of EMT markers in the two HCC cell lines. Transcriptome sequencing was performed to reveal the underlying mechanisms of DL anti-tumor; western blotting and qRT-PCR were employed to verify the mRNA and protein abundance of p53, p21, and CDK2; HepG2 xenograft in mice was used to test the anti-tumor effects of DL in vivo. Results: DL suppressed the proliferation of HCC cell lines (HepG2 and SK-HEP-1) but had little effect on a normal human liver cell line (L-O2). In addition, DL also induced apoptotic death of the HCC cells by activating Bax and downregulating Bcl-2. The antiproliferative effects of DL could be attributed to increased DNA damage and G1-phase cell cycle arrest. Moreover, DL inhibited HCC cell invasiveness and migration in vitro by decreasing the levels of β-catenin, N-cadherin, and TCF8/ZEB1, and increasing the E-cadherin level. RNA sequencing indicated that DL exerted its anti-hepatoma effects partly via regulation of p53-p21-CDK2 signaling. These results were validated by our in vivo experiments, in which DL markedly suppressed the growth of HepG2 xenografts in a mouse model without any toxic side effects, which corresponded to decreased expression of Ki67 and MMP9 in the tumor tissues. Conclusion: DL has significant anti-cancer effects in both in vivo and in vitro HCC models, and therefore could be further developed as a promising drug for the treatment of HCC.

Pentamode material (PM) is a special fluid-like acoustic metamaterial with intrinsic broadband merits. The unit cells of PM acoustic devices were based on single-material in previous reports, whose features make the available fabrication techniques very limited and the corresponding fabrication is not economic. In this investigation, a novel PM configuration composed of multi-materials is proposed to facilitate the designing and fabrication of PM devices. The novel multiphase PM configuration contains three parts: honeycomb-corrugation latticed microstructures, mass adjusting weights and interconnecting phases. The mass adjusting weights are bond to metallic latticed structure via interconnecting materials, while metallic lattices are fabricated by stamping forming technique. Simulated Annealing algorithm integrated with numerical homogenization method is developed for optimization of PM designing. A water impedance matching multiphase PM device based on this novel configuration was designed and verified in this study, and it was revealed from both numerical simulation and experiments that the designed multiphase PM device mimicked the acoustic properties of water below 25 kHz. The results indicate that the multiphase PM configuration exhibits superior performance on many aspects such as withstanding much higher hydrostatic pressure, cutting down manufacturing cost by 90% and reducing construction period by 98% compared with conventional techniques.

The field of two-dimensional (2D) nanomaterial-based cancer immunotherapy combines research from multiple subdisciplines of material science, nano-chemistry, in particular nano-biological interactions, immunology, and medicinal chemistry. Most importantly, the “biological identity” of nanomaterials governed by bio-molecular corona in terms of bimolecular types, relative abundance, and conformation at the nanomaterial surface is now believed to influence blood circulation time, bio-distribution, immune response, cellular uptake, and intracellular trafficking. A better understanding of nano-bio interactions can improve utilization of 2D nano-architectures for cancer immunotherapy and immunotheranostics, allowing them to be adapted or modified to treat other immune dysregulation syndromes including autoimmune diseases or inflammation, infection, tissue regeneration, and transplantation. The manuscript reviews the biological interactions and immunotherapeutic applications of 2D nanomaterials, including understanding their interactions with biological molecules of the immune system, summarizes and prospects the applications of 2D nanomaterials in cancer immunotherapy.

Hydrogels have blossomed as superstars in various fields, owing to their prospective applications in tissue engineering, soft electronics and sensors, flexible energy storage, and biomedicines. Two-dimensional (2D) nanomaterials, especially 2D mono-elemental nanosheets (Xenes) exhibit high aspect ratio morphology, good biocompatibility, metallic conductivity, and tunable electrochemical properties. These fascinating characteristics endow numerous tunable application-specific properties for the construction of Xene-based hydrogels. Hierarchical multifunctional hydrogels can be prepared according to the application requirements and can be effectively tuned by different stimulation to complete specific tasks in a spatiotemporal sequence. In this review, the synthesis mechanism, properties, and emerging applications of Xene hydrogels are summarized, followed by a discussion on expanding the performance and application range of both hydrogels and Xenes. Public summary: • Two-dimensional mono-elemental nanosheets (Xenes) endow tunable application • Synthesis mechanism, properties, and applications of Xene hydrogels are summarized • Expanding performance and applications of both hydrogels and Xenes are presented

A precise springback prediction is of great significance to reduce the manufacturing time and also to improve the forming quality for frame-rib parts. Based on Sobol and improved grey relation analysis, a novel prediction algorithm for springback of frame-rib parts in rubber forming process is proposed in this paper. First of all, the mapping model between springback angle and geometric parameters of the flange is established by using the response surface method and experiment. With the obtained mapping model, the weight of each parameter on springback is calculated by Sobol global sensitivity analysis method. Afterwards, a novel method for springback prediction is presented by incorporating k nearest-neighbor within improved grey relation analysis. A case study on springback angle prediction for the flange of rib part is given to validate the applicability and effectiveness of the proposed approach. Furthermore, by comparing the predicted values with the actual value of 18 cases, the high accuracy and stability of the proposed algorithm are further demonstrated.

Summary: Quantifying structural dissimilarities between networks is a fundamental and challenging problem in network science. Previous network comparison methods are based on the structural features, such as the length of shortest path and degree, which only contain part of the topological information. Therefore, we propose an efficient network comparison method based on network embedding, which considers the global structural information. In detail, we first construct a distance matrix for each network based on the distances between node embedding vectors derived from DeepWalk. Then, we define the dissimilarity between two networks based on Jensen-Shannon divergence of the distance distributions. Experiments on both synthetic and empirical networks show that our method outperforms the baseline methods and can distinguish networks well. In addition, we show that our method can capture network properties, e.g., average shortest path length and link density. Moreover, the experiment of modularity further implies the functionality of our method.

This paper is to study the influence of composition, microstructure and pore characteristics on the rock mechanical properties. Five kinds of sandstone compositions were analyzed by using X-ray diffraction instrument. And the microstructure was observed by using scanning electron microscope. Then the pore distribution characteristic was investigated by using the low field nuclear magnetic resonance equipment. Finally, the uniaxial compression test was carried out to investigate the mechanical characteristics by using RMT150C mechanics experimental system and the uniaxial compressive strength, Poisson’s ratio and elastic modulus were obtained. Compared to the analysis of the composition, structure and pore distribution and mechanical properties of the five kinds of sandstones, the relationship among composition, structure, pore distribution and mechanical properties was obtained. The results show that the composition, microstructure, pore distribution and mechanical properties of sandstone are closely related. With the decrease of feldspar and quartz particles, the compressive strength and elastic modulus increase, while the porosity decreases. Keywords: Mechanical characteristics, Pore characteristics, Microstructure, Composition, Scanning electron microscope

The paper presents the influence of varying immediate roof thickness on the lower strong roof strata movement and failure pattern in longwall coal mining with large mining height. The investigation is based on 58 geological drill holes and hydraulic shield pressure measurements around the longwall Panel 42105 of the Buertai Mine in Inner Mongolia Autonomous Region, China. The longwall Panel 42105 is characterized by relatively soft immediate roof strata of varying thickness superposed by strong strata, herein defined as lower strong roof. A voussoir beam model is adopted to interpret the structural movement of the lower strong roof strata and shield pressure measurements. It is shown that when the immediate roof is relatively thick, the broken overlying lower strong roof tends to form a stable voussoir beam with previously broken layer, thus not exerting high pressure on the hydraulic shield and working face. When the immediate roof is relatively thin, the broken overlying lower strong roof tends to behave as a cantilever beam, thus exerting higher pressure on the hydraulic shield and working face. Comparison of model predictions with measured time-weighted average shield pressure (TWAP) shows good agreement.

The balance between crop yield, quality and soil nutrient status can be manipulated by exploiting nutrient interactions. Field experiments were conducted in citrus orchards in Danjiangkou, Hubei Province to assess the effects of N (0, 0.3, 0.6 and 0.9 kg plant−1), P (0, 0.1, 0.2, 0.3 kg plant−1), K (0, 0.15, 0.30, 0.45 kg plant−1) and their interactions on residual nutrient content in soils, and the yield and quality of satsumas. The results showed that the effects of N and K fertilizers on the yield and quality of satsumas were greater than those of P fertilizers. Appropriate application rates of N (0.6 kg plant−1), P (0.3 kg plant−1) and K (0.15 kg plant−1) significantly improved yield and quality. Lack or excess or inappropriate ratios of N, P and K fertilizer can affect the absorption and utilization of nutrients and reduce yield and quality. The best fertilizer combination, determined by comprehensively considering yield, quality and environment, was N0.3P0.2K0.3, which delivered moderate yield, high fruit quality and low potential risk of pollution. The amount of fertilizer in this case was 0.3 kg N, 0.2 kg P, 0.3 kg K per plant, which is lower than the current recommended application rates (0.5–0.8 kg N, 0.2–0.5 kg P, 0.25–0.64 kg K, respectively). The economic benefit did not decrease because of a decline of yield, but increased slightly because of the improved fruit quality and the reduction in fertilizer input, compared with the treatment with the highest yield. Therefore, we suggest that it is necessary to consider the quality of agricultural products and environmental protection when applying fertilizer and to reduce N and P fertilizer input and appropriately increase the proportion of K. Keywords: Interaction of NPK fertilizer, Citrus, Balanced fertilization, Optimum fertilization rate, Yield, Quality