Reinforcement of natural rubber with core-shell structure silica-poly(Methyl Methacrylate) nanoparticles

A highly performing natural rubber/silica (NR/SiO2) nanocomposite with a SiO2 loading of 2 wt% was prepared by combining similar dissolve mutually theory with latex compounding techniques. Before polymerization, double bonds were introduced onto the surface of the SiO2 particles with the silane-coupling agent. The core-shell structure silica-poly(methyl methacrylate), SiO2-PMMA, nanoparticles were formed by grafting polymerization of MMA on the surface of the modified SiO2 particles via in situ emulsion, and then NR/SiO2 nanocomposite was prepared by blending SiO2-PMMA and PMMA-modified NR (NR-PMMA). The Fourier transform infrared spectroscopy results show that PMMA has been successfully introduced onto the surface of SiO2, which can be well dispersed in NR matrix and present good interfacial adhesion with NR phase. Compared with those of pure NR, the thermal resistance and tensile properties of NR/SiO2 nanocomposite are significantly improved

Causal relationships between circulating inflammatory factors and IgA vasculitis: a bidirectional Mendelian randomization study

BackgroundIgA vasculitis (IgAV) is an immune-associated vasculitis, yet its exact etiology remains unclear. Here, we explore the interaction between IgAV and inflammatory factors using bidirectional Mendelian randomization (MR).MethodsWe conducted a bidirectional summary-level MR analysis to delineate the causality of C-reactive protein (CRP), procalcitonin (PCT), and 41 circulating inflammatory regulators with IgAV. Data on genetic variants related to inflammation were obtained from three genome-wide association studies (GWASs) on CRP, PCT, and human cytokines, whereas data on IgAV was from large meta-analyses of GWAS among 216 569 FinnGen Biobank participants. The primary MR analysis was performed using the inverse-variance weighted (IVW) approach, and the sensitivity analyses were carried out using MR-Egger, weighted median, weighted mode, and MR-pleiotropy residual sum and outlier.ResultsThis study revealed the association of CRP higher levels with increased risk of IgAV through IVW method (Estimate odds ratio [OR] = 1.41, 95% confidence interval [CI]: 1.01-1.98, P = 0.04), MR-Egger (OR = 1.87, CI: 1.15-3.02, P = 0.01), weighted median (OR = 2.00, CI: 1.21-3.30, P = 0.01) and weighted mode (OR = 1.74, CI: 1.13-2.68, P = 0.02). Furthermore, elevated IL-8 was strongly implicated with a higher risk of IgAV (IVW OR = 1.42, CI: 1.05-1.92; P = 0.02). Conversely, genetically predicted IgAV was associated with decreased levels of TNF-β (IVW estimate β = -0.093, CI: -0.178 - -0.007; P = 0.033). Additionally, no such significant statistical differences for other inflammatory factors were found.ConclusionOur current study using bidirectional MR analysis provides compelling evidence for a causal effect of CRP, PCT, and circulating inflammatory regulators on IgAV. These findings contribute to a better understanding of the pathogenesis of IgAV and emphasize the potential of targeting inflammatory factors for therapeutic interventions

Landslide Susceptibility Assessment Based on Different MaChine Learning Methods in Zhaoping County of Eastern Guangxi

Regarding the ever increasing and frequent occurrence of serious landslide disaster in eastern Guangxi, the current study was implemented to adopt support vector machines (SVM), particle swarm optimization support vector machines (PSO-SVM), random forest (RF), and particle swarm optimization random forest (PSO-RF) methods to assess landslide susceptibility in Zhaoping County. To this end, 10 landslide disaster-related variables including digital elevation model (DEM)-derived, meteorology-derived, Landsat8-derived, geology-derived, and human activities factors were provided. Of 345 landslide disaster locations found, 70% were used to train the models, and the rest of them were performed for model verification. The aforementioned four models were run, and landslide susceptibility evaluation maps were produced. Then, receiver operating characteristics (ROC) curves, statistical analysis, and field investigation were performed to test and verify the efficiency of these models. Analysis and comparison of the results denoted that all four landslide models performed well for the landslide susceptibility evaluation as indicated by the area under curve (AUC) values of ROC curves from 0.863 to 0.934. Among them, it has been shown that the PSO-RF model has the highest accuracy in comparison to other landslide models, followed by the PSO-SVM model, the RF model, and the SVM model. Moreover, the results also showed that the PSO algorithm has a good effect on SVM and RF models. Furthermore, the landslide models devolved in the present study are promising methods that could be transferred to other regions for landslide susceptibility evaluation. In addition, the evaluation results can provide suggestions for disaster reduction and prevention in Zhaoping County of eastern Guangxi

Assessment impacts of climate variability and LULC change on net primary productivity in the process of rapid urbanization: a case study in Jianghan Plain of China

The goal of this study is to investigate the spatiotemporal variation characteristics of LULC and to explore the impact of climate variability and LULC change on regional NPP in Jianghan Plain from 2000 to 2010 based on the CASA model, remote sensing data sets, meteorological data and LULC data. The results are summarized as follows: (1) the significant geographical variations are characterized mainly by the transformation from farmland to wetlands and constructive land. (2) The highest yield of NPP was 557.37 gC/m2 in 2007, and the lowest yield was 483.45 gC/m2 in 2009. (3) NPP spatial distribution has obvious uneven characteristics on the regional scale. (4) The correlation analysis shows that the correlation coefficient between annual total NPP and the annual precipitation and annual temperature was –0.4471 and 0.6296, respectively. Finally, the results may provide scientific information for investigating the influence of climate variability and LULC change on regional NPP in China

A facile synthesis of mesoporous silica nanoparticle and its morphology manipulation by varying pH value

 Mesoporous silica nanoparticles (MSNs) with particle size of20 nm have been synthesised through the template directed method at low temperature. The pH value of the reaction solution was found to have a great impact on the morphology of the final products. The morphology of resultant MSNs were investigated through transmission electron microscope. The mesoporous structure was examined by Brunauer-Emmett-Teller and Barrett-Joyner-Halenda methods. The results suggested that the high pH value had a great effect on the morphology of the final MSNs. Higher pH value intensified the interaction between particles. The pH value less than 10 is good for the formation of nanoparticles, while at pH 12, a silica framework with heterogeneous mesopore structure can be obtained

The high renaissance properties of porous three dimensional graphene using one step reduction and its application in flexible conductor

 A super conductive graphene with continuous three dimensional (3D) porous structures that can potentially be used as flexible conductors has been produced by one step reduction of graphene oxide (GO) film. The high renaissance properties have been demonstrated by mechanical and electrical results where a noticeable increase in the electrical conductivity to 3850 S/cm has been demonstrated after embedding the 3D graphene foam into nearly insulated polydimethylsiloxane (PDMS). The graphene integrated PDMS film has a higher strain up to 100% elongation compared with the strain of only 60% for PDMS. Fourier transform infrared (FTIR) and x-ray photoemission spectroscopy (XPS) results reveal that most oxidized groups have been removed, which contributes to the renaissance of most outstanding properties of graphene because of the recovery of sp2 carbon structures

Synthesis and Antiproliferative Activity of Steroidal Thiosemicarbazone Platinum (Pt(II)) Complexes

Steroidal compounds exhibit particular physiological activities. In this paper, some steroidal thiosemicarbazones platinum (Pt(II)) complexes were synthesized by the condensation of steroidal ketones with thiosemicarbazide using estrone, chenodeoxycholic acid, and 7-deoxycholic acid as starting materials and complexation of steroidal thiosesemicarbazones with Pt(II). The complexes were characterized by IR, NMR, and MS, and their antiproliferative activities were evaluated. The results showed that some steroidal thiosemicarbazones platinum (Pt(II)) complexes displayed moderate cytotoxicity to HeLa and Bel-7404 cells. Thereinto, complex 6 showed an excellent inhibited selectivity to HeLa cells with an IC50 value of 9.2 μM and SI value of 21.7. At the same time, all compounds were almost inactive to HEK293T (normal kidney epithelial cells). The information obtained from the studies may be useful for the design of novel chemotherapeutic drugs

Identification of Hydrothermal Alteration Minerals for Exploring Gold Deposits Based on SVM and PCA Using ASTER Data: A Case Study of Gulong

Dayaoshan, as an important metal ore-producing area in China, is faced with the dilemma of resource depletion due to long-term exploitation. In this paper, remote sensing methods are used to circle the favorable metallogenic areas and find new ore points for Gulong. Firstly, vegetation interference was removed by using mixed pixel decomposition method with hyperplane and genetic algorithm (GA) optimization; then, altered mineral distribution information was extracted based on principal component analysis (PCA) and support vector machine (SVM) methods; thirdly, the favorable areas of gold mining in Gulong was delineated by using the ant colony algorithm (ACA) optimization SVM model to remove false altered minerals; and lastly, field surveys verified that the extracted alteration mineralization information is correct and effective. The results show that the mineral alteration extraction method proposed in this paper has certain guiding significance for metallogenic prediction by remote sensing