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Background: Osteosarcoma (OS) is the most common primary tumor of bone in adolescents, and its survival rate is generally less than 20% when metastases occur. Necroptosis, a novel form of programmed necrotic cell death distinct from apoptosis, has been increasingly recognized as a promising therapeutic strategy. This study sought to identify long non-coding RNAs (lncRNAs) associated with necrotizing apoptosis to predict prognosis and target drug use to improve patient survival.Methods: Transcriptomic data and clinical data from 85 OS patients with survival time data and expression profiles from 85 random normal adipose tissue samples were extracted from the UCSC Xena website (http://xena.ucsc.edu/). Nine necroptosis-associated differential prognostic lncRNAs were then identified by analysis of variance, correlation analysis, univariate Cox (uni-Cox) regression, and Kaplan–Meier analysis. Then, patients were randomized into training or testing groups. According to uni-Cox, we obtained prognostic lncRNAs in the training group and intersected them with the abovementioned nine lncRNAs to obtain the final necrotizing apoptosis–related differential prognostic lncRNAs (NRlncRNAs). Next, we performed the least absolute shrinkage and selection operator (LASSO) to construct a risk model of NRlncRNAs. Kaplan–Meier analysis, ROC curves, nomograms, calibration curves, and PCA were used to validate and evaluate the models and grouping. We also analyzed the differences in tumor immunity and drugs between risk groups.Results: We constructed a model containing three NRlncRNAs (AL391121.1, AL354919.2, and AP000851.2) and validated its prognostic predictive power. The value of the AUC curve of 1-, 3-, and 5-year survival probability was 0.806, 0.728, and 0.731, respectively. Moreover, we found that the overall survival time of patients in the high-risk group was shorter than that in the low-risk group. GSEA and ssGSEA showed that immune-related pathways were mainly abundant in the low-risk group. We also validated the differential prediction of immune checkpoint expression, tumor immunity, and therapeutic compounds in the two risk groups.Conclusion: Overall, NRlncRNAs have important functions in OS, and these three NRlncRNAs can predict the prognosis of OS and provide guidance for immunotherapy in OS.

HR-2 is a single-phase austenitic stainless steel with excellent hydrogen embrittlement resistance and a wide range of applications in hydrogen storage pressure vessels. During the powder preparation and additive manufacturing process, burning nitrogen deteriorates its hydrogen embrittlement resistance and mechanical properties. In this paper, HR-2 stainless steel powder was prepared by vacuum induction melting atomization (VIGA), and the HR-2 powder with acceptable nitrogen content was obtained in a nitrogen atmosphere. The effects of process parameters in selective laser melting, including laser energy density on the part density, microstructure, and mechanical properties of the formed specimens, were investigated. The results show the density of the formed samples first increase and then decrease as the energy density increases. With the optimization of process parameters, the density of the parts fabricated by SLM formed HR-2 with low nitrogen can reach more than 99.5%, the tensile strength can reach 735 ± 5 MPa, the yield strength can reach 415 ± 10 MPa, the percentage elongation of 43 ± 5%, and percentage reduction of 44 ± 5%, while the tensile strength of HR-2 with high nitrogen can reach 720 ± 10 MPa, the yield strength can reach 603.5 ± 10 MPa, the percentage elongation of 45 ± 5%, and percentage reduction of 60 ± 5%, which are comparable with the base material of forged HR-2.

Additional file 1: Figure S1. Rarefaction curves in observed_species of all the samples. The rarefaction curves constructed from the sequenced data has been basically stable, indicating that the sequenced data has benn basically stable at this sequencing depth.

Additional file 1: Supporting information including additional methods and figures.

Additional file 2: Figure S2. The taxonomic representation of statistically and biologically differences between High 25(OH)D group and Low 25(OH)D group. The color of discriminative taxa represents the taxa is more abundant in the corresponding group (High 25(OH)D group in blue, Low 25(OH)D group in orange).

Additional file 3: Figure S3. Functional PICRUSt analysis among the LVD and HVD group. Kyoto Encyclopedia of Genes(A) and Genomes and cluster of orthologous group(B) was used to further investigate the mechanism of intestinal flora.

Additional file 4: Figure S4. Heat map for spearman correlation analysis between fecal metabolites and discriminative genera at the family level. Only significant values (p < 0.05 after FDR adjustment) are shown. Orange and blue colors represent significant positive correlations and negative correlations. Darker color represents stronger correlations.

Additional file 4: Figure S4. Heat map for spearman correlation analysis between fecal metabolites and discriminative genera at the family level. Only significant values (p < 0.05 after FDR adjustment) are shown. Orange and blue colors represent significant positive correlations and negative correlations. Darker color represents stronger correlations.

Additional file 3: Figure S3. Functional PICRUSt analysis among the LVD and HVD group. Kyoto Encyclopedia of Genes(A) and Genomes and cluster of orthologous group(B) was used to further investigate the mechanism of intestinal flora.

Additional file 2: Figure S2. The taxonomic representation of statistically and biologically differences between High 25(OH)D group and Low 25(OH)D group. The color of discriminative taxa represents the taxa is more abundant in the corresponding group (High 25(OH)D group in blue, Low 25(OH)D group in orange).

Absract Polylactic acid (PLA), due to its high mechanical strength, biocompatibility, excellent biodegradability and good processing characteristics, can be used to print the bone scaffold with complex structures, but the poor cell affinity and inflammation resulted by the acidity of intermediate produce still pose a challenge. To address these issues, o-carboxymethyl chitosan (CMC) was used to modify PLA, and the phase miscibility of PLA/CMC blends with different component ratios was investigated by a multi-scale method. Here, molecular simulation and experimental methods were applied to predict the miscibility of polylactic acid and o-carboxymethyl chitosan blends. Results indicated that PLA and CMC are miscible when the concentration of CMC in blends below 20 wt%, and partially miscible at 30 wt% concentration of CMC, but completely immiscible at higher CMC content (>30 wt%). Conclusions from this work can be used to forecast the miscibility of PLA/CMC composites at different compositions and can provide a scientific basis for formula designs of PLA/CMC polymer composites for 3D printing artificial bone scaffolds.

In order to improve the intelligence of automobile management system and improve the efficiency of modern automobile management, this paper puts forward a novel intelligent automobile management system based on a variety of cutting-edge science and technology. The system is mainly based on the Internet platform and integrates a variety of advanced science and technology, such as automation technology, artificial intelligence technology and Internet of things technology. The research results show that the intelligent vehicle management system can improve the intelligence and safety of the vehicle management system, and can realize large-scale batch vehicle management.

Scanning speed is a critical parameter for laser process, which can play a key role in the microstructure evolution of laser melting. In the laser melting of single crystal superalloy, the effects of scanning speed were investigated by experimental analysis and computational simulation. The laser was scanning along [ 7 1 ¯ 0 ] direction on (001) surface in different speeds. Solidification microstructures of dendrites growth direction and the primary dendritic spacing were analyzed by metallograph. Besides, a planar interface during solidification was taken into attention. Experiment results indicated that the primary dendritic spacing and thickness of planar interface decrease with the increase of speed. Through simulation, distribution of dendrites growth velocity and thermal gradient along dendrite growth direction were calculated, and the simulation of dendrites growth direction agreed with the experiment results. Additionally, a constant value was acquired which can be used to predict the primary dendritic spacing. Moreover, according to curve-fitting method and inequality relation, a model was proposed to predict the thickness of planar interface.

A nickel-based superalloy was deposited onto a single crystal substrate based on epitaxial laser metal forming (E-LMF). The microstructure development in two depositions has been researched. For the first time, the crystal orientation of dendrites varying beyond 20° was found when the dendrites deflected in deposition. In addition, a new grain boundary was found between different orientation dendrites in a grain, and the detected grain boundary angle was 23°. The result shows that flowing field in laser pool is responsible for this phenomenon.

High-strength aluminum alloy with Sc-Zr is specially optimized for Selective Laser Melting (SLM). The alloy has a great potential in structurally optimized lightweight parts in the fields of aerospace, nuclear power and automobile due to its good formability, fine microstructure, and excellent mechanical properties. An appropriate heat treatment for this alloy is critical to improve its ultimate tensile strength. However, the effect of heat treatments on the microstructure and mechanical properties of SLMed Al-Mg-Sc-Zr alloy is not fully understood and heat treatment needs to be optimized. In this investigation, the effect of 500 °C homogenization and 330 °C ageing on the microstructure and properties of the SLMed parts were investigated. The results show that a homogenization treatment at 500 °C does not increase the solubility of the alloy elements, but accelerates the precipitation of Sc/Zr elements and recrystallization. Moreover, homogenization with holding time longer than 2 h results in a decrease of mechanical properties including both tensile properties and ductility compared with those of the as-built state. Ageing treatment at 330 °C for 1 h drives the second phase of Al3(ScxZr1-x) to fully precipitate, and long-term ageing for 8 h neither leads to recrystallize nor deteriorates the properties of the alloy. A rapid ageing heat treatment at 330 °C for 1 h was explored, with a tensile strength of 479 MPa, a yield strength of 441 MPa, an elongation after break of 14.5%, and a shrinkage of 45%. Specimens of SLMed Al-Mg-Sc-Zr alloy are strengthened by fine grains whose formation is driven by extremely high temperature gradients and solidification rates, and precipitation of the second phase Al3(ScxZr1-x) caused by ageing. The Orawan bypass mechanism plays an important role in the strengthening of the aged SLMed Al-Mg-Sc-Zr alloy.

A vectorization analysis technique for crystal growth and microstructure development in single-crystal weld was developed in our previous work. Based on the vectorization method, crystal growth and stray grain distribution in laser surface remelting of single crystal superalloy CMSX-4 were investigated in combination of simulations with experimental observations. The energy distribution of laser was taken into consideration in this research. The experimental results demonstrate that the simulation model applies well in the prediction of dendrite growth direction. Moreover, the prediction of stray grain distribution works well except for the region of dendrites growing along the [100] direction.

According to the principle of plasma spraying, air plasma spraying Al2O3-13 wt % TiO2/NiCrAl coating (AT13) on Q235 steel-substrate have some important disadvantages of high porosity, poor adhesive to substrate and low cohesive within the coating. Owing to such weaknesses, an enhancing densification and improving bonding of plasma-sprayed AT13 with an appropriate post air heat treatment is an effective method. On the basis of our final experimental results, post air heating treatment could improve the bonding strength and micro-structure of AT13. The AT13 shows the highest bonding strength and lowest Porosity when heating up to 560°C for 6 hours. Such performances may be because the re-crystallizing, reaction-diffusion of element diffusion and compressive stress of transitional layer. However, air heating temperature higher than 560°C led to the decline of the bonding strength. The excessive oxidizing products and compressive stress of oversized transitional layer could be contributed to the phenomenon.

Reagents are optimized for the simultaneous determination of trace amounts of Cu2+, Cd2+ and Co2+ in zinc sulfate solution, which contains an extremely large excess of Zn2+. First, the reagents and their doses for the experiment are selected according to the characteristics of the zinc sulfate solution. Then, the reagent doses are optimized by analyzing the influence of reagent dose on the polarographic parameters (i.e. half-wave potential E 1/2 and limiting diffusion current I p ). Finally, the optimization results are verified by simultaneously determining trace amounts of Cu2+, Cd2+ and Co2+ in the presence of an extremely large excess of Zn2+. The determination results indicate that the optimized reagents exhibit wide linearity, low detection limits, high accuracy and good precision for the simultaneous determination of trace amounts of Cu2+, Cd2+ and Co2+ in the presence of an extremely large excess of Zn2+.

A geometric analysis technique for crystal growth and microstructure development in single-crystal welds had been previously developed. And the effect of welding conditions on the tendency of stray grains formation during solidification was researched. In the present work, these analytical methods were further extended. Combined with an original vectorization method, a 3D Rosenthal solution was used to determine thermal conditions of the welds. Afterward, the dendrite growth orientation, the dendrite growth velocity and the thermal gradient along dendrite direction were calculated and lively plotted. Finally, the tendency of stray grains formation in the solidification front was forecasted and its distribution was presented with a 3D plot. The results indicate that substrate orientation has some impacts on the crystal growth pattern, dendrite growth velocity, distribution of thermal gradient and stray grain. Based on the research methods proposed in this work, any substrate crystallographic orientation can be studied, and predicted stray grains distribution can be visualized.

To resolve the overlapping linear sweep voltammetric peaks (LSVPs) in the case of small signals overlapping to a very big one, a parameter optimization method based on state-transition-algorithm (STA) is investigated. First, four special state transformation operators of STA are introduced and a parameter optimization method is proposed. Then, the overlapping LSVPs are obtained by simultaneously determining trace amounts of Cd2 + and Co2 + in the presence of a high concentration of Zn2 + based on optimized reagents. Finally, overlapping LSVPs are resolved into independent sub-peaks using the proposed method. The resolution results show that the goodness-of-fit of fitting curve in describing the overlapping LSVPs is more than 97%. It indicates that the proposed method is reasonable and effective for the resolution of overlapping LSVPs in the case of high signal ratio which is more than 50.

Monochlorobenzene (MCB) pollution in the groundwater has attracted extensive attention due to its high toxicity and refractory. Ferrous-activated persulfate process (Fe2+/PS) is feasible to degrade MCB; however, the slow redox cycle of Fe2+/Fe3+ and the narrow valid pH range limit its application. In this study, cysteine (Cys) cooperating with the Fe2+/PS process (Fe2+/Cys/PS) can be employed to enhance the MCB degradation owing to its reduction and complexation ability, in which the effects of Cys, Fe2+, PS concentrations, and the value of pH were evaluated. Existences of sulfate radicals (SO4 −) and hydroxyl radicals (HO ) were confirmed by radical scavenger tests and Electron paramagnetic resonance (EPR) studies, in which HO was mainly responsible for MCB degradation in Fe2+/Cys/PS process. According to the aforementioned results, a potential mechanism and a plausible pathway of MCB degradation were proposed. The Fe2+/Cys complex can be repeatedly reused in practical applications. Likewise, the excellent performance of Fe2+/Cys/PS process in the degradation of MCB was also observed in the real groundwater. In summary, the novel Fe2+/Cys/PS process might provide a potentially effective technique for remediation of organic-contaminated groundwater.

A resolution method based on Gaussian-like distribution for overlapped linear sweep polarographic peaks was proposed to simultaneously detect the polymetallic components, such as Zn(II) and Co(II), coexisting in the leaching solution of zinc hydrometallurgy. A Gaussian-like distribution was constructed as the sub-model of overlapped peaks by analyzing the characteristics of linear sweep polarographic curve. Then, the abscissas of each peak and trough were pinpointed through multi-resolution wavelet decomposition, the curve and its derivative curves were fitted by using nonlinear weighted least squares (NWLS). Finally, overlapped peaks were resolved into independent sub-peaks based on fitted reconstruction parameters. The experimental results show that the relative error of half-wave potential pinpointed by multi-resolution wavelet decomposition is less than 1% and the accuracy of I p fitted by NWLS is higher than 96%. The proposed resolution method is effective for overlapped linear sweep polarographic peaks of Zn(II) and Co(II).

Food-derived Angiotensin-I-Converting Enzyme (ACE)-inhibitory peptides have safety advantages over synthetic peptides. The application of complex enzymatic (alcalase and trypsin) in producing such peptides from goat milk casein seldom be focused. In this study, the pH, complex protease ratio (CPR) and enzyme to substrate ratio (E/S) were optimized by Response surface methodology (RSM). The optimized conditions were: pH 8.4, CPR 1:1, and E/S 8.5%. In these conditions, the ACE-inhibitory activity of the obtained hydrolysates reached 91.99%. The response model was qualified to predict the reaction optimization. Hydrolysate fragments were purified consecutively. A fraction G2-2a exhibited highest ACE-inhibitory activity 93.50% with IC50 value of 72.14 μg/mL.

In precision agriculture there exist two sorts of data—high‐dimensional space data and property data. We propose a precision fertilisation method based on a spatial fuzzy clustering algorithm and apply it to the National 863 Project “Corn Precision Task Systems Research and Application”. Our research methods include: (1) use of DGPS and GIS to obtain and to process soil spatial information and property information; (2) use of fuzzy clustering analysis to carry out systematic soil nutrient research and to develop classification models; (3) use of the 8‐adjacent connection traverse algorithm to carry out spatial clustering analysis and to apply the results to spatial clustering. This two‐stage clustering method is superior to the more traditional single‐stage clustering methods. Based on clustering results, we can make corn precision fertilisation decisions and can also make decisions relating to other precision agricultural field management issues and operations. It is shown by experiment that thi...

It has been reported that copper melted in a graphite crucible at high temperature will give off its oxygen content mainly as CO and partially as CO(2). Thus if oxygen in copper is determined by means of apparatus designed to measure only CO as the reaction product, the results are obviously liable to error. Methods of suppressing formation of CO(2) during the fusion process are proposed. When the oxygen is determined by gas chromatography, formation of CO(2) can be suppressed by adding a 0.5% Si-1.5% NiCu bath-alloy together with the copper sample or by inserting a spectrographically pure carbon rod into the graphite crucible used for the fusion. When the oxygen is determined by coulometry, formation of CO(2) can be suppressed by the addition of the SiNiCu bath-alloy or by appropriate modification of the graphite crucible to obtain an optimum working temperature. The results obtained by either method are in agreement with those obtained by a modified vacuum fusion method in which CO and CO(2) can both be measured. These methods have been validated by analysis of two standard reference materials.