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The impact of different oxidation atmospheres on the formation of magnesium-bearing magnetite in the Fe3O4–MgO and Fe2O3–MgO systems was investigated using FactSage 8.3 thermodynamic modeling, XRD, XPS, and SEM-EDS. This study also examined the influence of MgO on the compression strength, mineral phase composition, and microstructure of oxidized roasting magnetite pellets. At 500 °C, Fe3O4 oxidized into fine crystalline nuclei of Fe2O3. Subsequently, at 900 °C, Fe2O3 reacted with MgO to completely form magnesia-bearing magnetite. Conversely, in a vacuum, Fe3O4 and MgO did not produce magnesium-bearing magnetite. For the Fe2O3–MgO system under vacuum, only a small quantity of magnesia-containing magnetite was generated when the temperature reached 900 °C, which was substantially less than that produced in an O2 atmosphere from Fe3O4 with MgO. The formation of magnesia-containing magnetite was closely associated with the nucleation of hematite grains during the oxidation roasting process of magnetite. Increasing the MgO content in the pellets led to a higher MgO content in the spinel phase, while the contents in the pyroxene and slag phases remained relatively stable. Additionally, the Fe2+/(Fe2+ + Fe3+) ratio in the pellets increased as the MgO content rose. During the preparation of hematite pellets through the oxidation roasting of magnetite, the oxidation of magnetite to hematite followed by reaction with MgO resulted in the formation of magnesium-bearing magnetite, which subsequently reduced the compressive strength of the pellets.

MgH2, albeit with slow desorption kinetics, has been extensively studied as one of the most ideal solid hydrogen storage materials. Adding such catalyst as Ni can improve the desorption kinetics of MgH2, whereas the catalytic role has been attributed to different substances such as Ni, Mg2Ni, Mg2NiH0.3, and Mg2NiH4. In the present study, Ni nanoparticles (Ni-NPs) supported on mesoporous carbon (Ni@C) have been synthesized to improve the hydrogen desorption kinetics of MgH2. The utilization of Ni@C largely decreases the dehydrogenation activation energy from 176.9 to 79.3 kJ mol−1 and the peak temperature of dehydrogenation from 375.5 to 235 °C. The mechanism of Ni catalyst is well examined by advanced aberration-corrected environmental transmission electron microscopy and/or x-ray diffraction. During the first dehydrogenation, detailed microstructural studies reveal that the decomposition of MgH2 is initially triggered by the Ni-NPs, which is the rate-limiting step. Subsequently, the generated Mg reacts rapidly with Ni-NPs to form Mg2Ni, which further promotes the dehydrogenation of residual MgH2. In the following dehydrogenation cycle, Mg2NiH4 can rapidly decompose into Mg2Ni, which continuously promotes the decomposition of MgH2. Our study not only elucidates the mechanism of Ni catalyst but also helps design and assemble catalysts with improved dehydriding kinetics of MgH2.

Abstract Modern data center topologies often take the form of a multi-rooted tree with rich parallel paths to provide high bandwidth. However, various path diversities caused by traffic dynamics, link failures and heterogeneous switching equipment widely exist in the production datacenter network. Therefore, the multi-path load balancer in data center should be robust to these diversities. Although prior fine-grained schemes such as RPS and Presto make the best use of available paths, However, they are prone to experiencing packet reordering problem under the asymmetric topology. The coarse-grained solutions such as ECMP and LetFlow effectively avoid packet reordering, but easily lead to under-utilization of multiple paths. To cope with these inefficiencies, we propose a load balancing mechanism called PDLB, which adaptively adjusts flowcell granularity according to path diversity. PDLB increases flowcell granularity to alleviate packet reordering under large degrees of topology asymmetry, while reducing flowcell granularity to obtain high link utilization under small degrees of topology asymmetry. PDLB is only deployed on the sender without any modification on switch. We evaluate PDLB through large-scale NS2 simulations. The experimental results show that PDLB reduces the average flow completion time by up to $$\sim$$ ∼ 8-53% over the state-of-the-art load balancing schemes.

BackgroundHealthcare resources are necessary for individuals to maintain their health. The Chinese government has implemented policies to optimize the allocation of healthcare resources and achieve the goal of equality in healthcare for the Chinese people since the implementation of the new medical reform in 2009. Given that no study has investigated regional differences from the perspective of healthcare resource agglomeration, this study aimed to investigate China’s healthcare agglomeration from 2009 to 2017 in China and identify its determinants to provide theoretical evidence for the government to develop and implement scientific and rational healthcare policies.MethodsThe study was conducted using 2009–2017 data to analyze health-resource agglomeration on institutions, beds, and workforce in China. An agglomeration index was applied to evaluate the degree of regional differences in healthcare resource allocation, and spatial econometric models were constructed to identify determinants of the spatial agglomeration of healthcare resources.ResultsFrom 2009 to 2017, all the agglomeration indexes of healthcare exhibited a downward trend except for the number of institutions in China. Population density (PD), government health expenditures (GHE), urban resident’s disposable income (URDI), geographical location (GL), and urbanization level (UL) all had positive significant effects on the agglomeration of beds, whereas both per capita health expenditures (PCHE), number of college students (NCS), and maternal mortality rate (MMR) had significant negative effects on the agglomeration of institutions, beds, and the workforce. In addition, population density (PD) and per capita gross domestic product (PCGDP) in one province had negative spatial spillover effects on the agglomeration of beds and the workforce in neighboring provinces. However, MMR had a positive spatial spillover effect on the agglomeration of beds and the workforce in those regions.ConclusionThe agglomeration of healthcare resources was observed to remain at an ideal level in China from 2009 to 2017. According to the significant determinants, some corresponding targeted measures for the Chinese government and other developing countries should be fully developed to balance regional disparities in the agglomeration of healthcare resources across administrative regions.

An improved method for rockbolt fracture is proposed in this paper to determine the exact fracture position of rockbolts simulated using cable structural elements (cableSELs) in FLAC3D. This method employs the total elongation of the free segment of the rockbolt as the fracture criterion. The maximum deformation position is identified by comparing the length of each cableSEL in the free segment, leading to the fracture. The simulation results validated through a rockbolt tensile test closely match actual conditions. The proposed method was used to optimize the roadway support in deep extra-thick coal seams (DECSs). Optimized parameters were obtained by simulating and analyzing different lengths and spacings of rockbolts and anchor cables. The field implementation conducted shows that the optimized deformation and support strength of the roadway meet safety needs.

Abstract Soil and water assessment tool (SWAT) model was used to calculate the runoff, nitrogen and phosphorus emissions in the Dagu River Basin from 2002 to 2012 and provided preliminary suggestions on environmental protection measures. Calibration on hydrological watershed parameters was obtained from data obtained from multiple representative stations. Cluster analysis was used to group all stations, and the parameters of different representative stations were applied to the entire geographical area to reflect the hydrological conditions of the basin. Additionally, the spatiotemporal changes and pollution source characteristics of nitrogen and phosphorus were analyzed. Anthropogenic sources—chemical fertilizer loss and livestock breeding—accounted for 49.9–29.6% of total nitrogen (TN) and 41.4% and 40.3% of total phosphorus (TP), respectively. Non-point sources accounted for 85.8% of the TN and 89.4% of the TP. Six landscape management practices were set up to evaluate the reduction effect on non-point source pollution loads, and comprehensive measures were proposed to reduce TN (TP) by ~ 70%. According to water quality model, the response relationship between river control and nutrient distribution in Jiaozhou Bay is calculated. Based on the findings, we propose an optimal control scheme for non-point source pollution in the Dagu River Basin and other similar basins.

ObjectiveThe study aimed to measure time trends of inequalities of the geographical distribution of health facilities and workforce in Shanghai from 2010 to 2016 and used a spatial autocorrelation analysis method to precisely detect the priority areas for optimizing health resource reallocation in metropolises like Shanghai in developing countries.MethodsThe study used secondary data from the Shanghai Health Statistical Yearbook and the Shanghai Statistical Yearbook from 2011 to 2017. Five indicators on health resources, namely, health institutions, beds, technicians, doctors, and nurses, were employed to quantitatively measure the healthcare resource in Shanghai. The Theil index and the Gini coefficient were applied to assess the global inequalities in the geographic distribution of these resources in Shanghai. Global and local spatial autocorrelation was performed using global Moran's index and local Moran's index to illustrate the spatial changing patterns and identify the priority areas for two types of healthcare resource allocation.ResultsShanghai's healthcare resources showed decreasing trends of inequalities at large from 2010 to 2016. However, there still existed an unchanged over-concentration distribution in healthcare facilities and workforce density among districts in Shanghai, especially for doctors at the municipal level and facility allocation at the rural level. Through spatial autocorrelation analysis, it was found that there exhibited a significant spatial autocorrelation in the density distribution of all resources, and some identified priority areas were detected for resource re-allocation policy planning.ConclusionThe study identified the existence of inequality in some healthcare resource allocations in Shanghai from 2010 to 2016. Hence, more detailed area-specific healthcare resource planning and distribution policies are required to balance the health workforce distribution at the municipal level and institution distribution at the rural level, and particular geographical areas (low–low and low–high cluster areas) should be focused on and fully considered across all the policies and regional cooperation to ensure health equality for municipal cities like Shanghai in developing countries.

Triadic silica-supported polyhexamethylene guanidine@nano-hydroxyapatite (HAP) composites were prepared and employed in a micro-column system for solid phase extraction of Cr (VI) with its determination by flame atomic absorption spectrometry (FAAS). It is found that the triadic silica-supported nano-HAP composites can efficiently adsorb Cr (VI) at pH 4.0–6.0, but absorb almost no Cr (III). The detection has a good linear range of 0.3–300 μg L−1, a detection limit of 0.09 μg L−1 (3σ, n = 11) and a precision of 1.3% (20 μg L−1, n = 11) on Cr (VI). The adsorption mechanisms are mainly electrostatic attraction and the channel effect. This method was successfully applied to the determination of chromium contents in cereal and water samples with recoveries of 99.5–109.8%.

Abstract Background Cancer metastasis and drug resistance have traditionally been studied separately, though these two lethal pathological phenomena almost always occur concurrently. Brain metastasis occurs in a large proportion of lung cancer patients (~ 30%). Once diagnosed, patients have a poor prognosis surviving typically less than 1 year due to lack of treatment efficacy. Methods Human metastatic lung cancer cells (PC-9-Br) were injected into the left cardiac ventricle of female athymic nude mice. Brain lesions were allowed to grow for 21 days, animals were then randomized into treatment groups and treated until presentation of neurological symptoms or when moribund. Prior to tissue collection mice were injected with Oregon Green and 14C-Aminoisobutyric acid followed by an indocyanine green vascular washout. Tracer accumulation was determined by quantitative fluorescent microscopy and quantitative autoradiography. Survival was tracked and tumor burden was monitored via bioluminescent imaging. Extent of mutation differences and acquired resistance was measured in-vitro through half-maximal inhibitory assays and qRT-PCR analysis. Results A PC-9 brain seeking line (PC-9-Br) was established. Mice inoculated with PC-9-Br resulted in a decreased survival time compared with mice inoculated with parental PC-9. Non-targeted chemotherapy with cisplatin and etoposide (51.5 days) significantly prolonged survival of PC-9-Br brain metastases in mice compared to vehicle control (42 days) or cisplatin and pemetrexed (45 days). Further in-vivo imaging showed greater tumor vasculature in mice treated with cisplatin and etoposide compared to non-tumor regions, which was not observed in mice treated with vehicle or cisplatin and pemetrexed. More importantly, PC-9-Br showed significant resistance to gefitinib by in-vitro MTT assays (IC50 > 2.5 μM at 48 h and 0.1 μM at 72 h) compared with parental PC-9 (IC50: 0.75 μM at 48 h and 0.027 μM at 72 h). Further studies on the molecular mechanisms of gefitinib resistance revealed that EGFR and phospho-EGFR were significantly decreased in PC-9-Br compared with PC-9. Expression of E-cadherin and vimentin did not show EMT in PC-9-Br compared with parental PC-9, and PC-9-Br had neither a T790M mutation nor amplifications of MET and HER2 compared with parental PC-9. Conclusion Our study demonstrated that brain metastases of lung cancer cells may independently prompt drug resistance without drug treatment.

The failure of tube heat exchangers is an acute problem in industry and, in most cases, is due to the solid particle erosion of a few tubes. Identifying the critical erosion surfaces and thereafter changing the particle impingement pattern on the surfaces is one of the solutions to increase the lifetime of heat exchangers. In this work the fluid flow, solid particle motion and metal erosion of different two-pass copper-tube heat exchangers were simulated with a refined model and the sophisticated RANS-SST approach. The results showed the importance of the model in capturing the asymmetrical flow, uneven fluid distribution through tube bundle and other flow features for better erosion prediction. The erosion characteristics of three heat exchangers were compared to evaluate their structure with respect to producing low erosion. The simulations provided basic data for identifying the critical areas and damage locations of each heat exchanger. It was found that the particle separation in the inlet header altered the critical erosion locations but did not significantly affect the erosion rate. Theerosion rates at critical areas were also predicted. The results can be applied for predicting the service life and improving the structure of tube heat exchangers.

Abstract Materials with a layered structure have attracted tremendous attention because of their unique properties. The ultrathin nanosheet structure can result in extremely rapid intercalation/de-intercalation of Na ions in the charge–discharge progress. Herein, we report a manganese oxide with pre-intercalated K and Na ions and having flower-like ultrathin layered structure, which was synthesized by a facile but efficient hydrothermal method under mild condition. The pre-intercalation of Na and K ions facilitates the access of electrolyte ions and shortens the ion diffusion pathways. The layered manganese oxide shows ultrahigh specific capacity when it is used as cathode material for sodium-ion batteries. It also exhibits excellent stability and reversibility. It was found that the amount of intercalated Na ions is approximately 71% of the total charge. The prominent electrochemical performance of the manganese oxide demonstrates the importance of design and synthesis of pre-intercalated ultrathin layered materials.

Objective: To evaluate the treatment effects and stability of Forsus appliance therapy.

Although emerging evidence indicates that deep-sea water contains an untapped reservoir of high metabolic and genetic diversity, this realm has not been studied well compared with surface sea water. The study provided the first integrated meta-genomic and -transcriptomic analysis of the microbial communities in deep-sea water of North Pacific Ocean. DNA/RNA amplifications and simultaneous metagenomic and metatranscriptomic analyses were employed to discover information concerning deep-sea microbial communities from four different deep-sea sites ranging from the mesopelagic to pelagic ocean. Within the prokaryotic community, bacteria is absolutely dominant (~90%) over archaea in both metagenomic and metatranscriptomic data pools. The emergence of archaeal phyla Crenarchaeota, Euryarchaeota, Thaumarchaeota, bacterial phyla Actinobacteria, Firmicutes, sub-phyla Betaproteobacteria, Deltaproteobacteria, and Gammaproteobacteria, and the decrease of bacterial phyla Bacteroidetes and Alphaproteobacteria are the main composition changes of prokaryotic communities in the deep-sea water, when compared with the reference Global Ocean Sampling Expedition (GOS) surface water. Photosynthetic Cyanobacteria exist in all four metagenomic libraries and two metatranscriptomic libraries. In Eukaryota community, decreased abundance of fungi and algae in deep sea was observed. RNA/DNA ratio was employed as an index to show metabolic activity strength of microbes in deep sea. Functional analysis indicated that deep-sea microbes are leading a defensive lifestyle.

The alignment of nanostructures in materials such as lyotropic liquid crystal (LLC) templated materials has the potential to significantly improve their performances. However, accurately characterising and quantifying the alignment of such fine structures remains very challenging. In situ small angle X-ray scattering (SAXS) and molecular dynamics were employed for the first time to understand the hexagonal LLC alignment process with magnetic nanoparticles under a magnetic field. The enhanced alignment has been illustrated from the distribution of azimuthal intensity in the samples exposed to magnetic field. Molecular dynamics simulations reveal the relationship between the imposed force of the magnetic nanoparticles under magnetic field and the force transferred to the LLC cylinders which leads to the LLC alignment. The combinational study with experimental measurement and computational simulation will enable the development and control of nanostructures in novel materials for various applications.

Benzo[a]pyrene (BaP), a well-known environmental carcinogen, promotes oxidative stress and DNA damage. Curcumin and vitamin E (VE) have potent antioxidative activity that protects cells from oxidative stress and cellular damage. The objectives of the present study were to investigate the adverse effects of BaP on normal human lung epithelial cells (BEAS-2B), the potential protective effects of curcumin and VE against BaP-induced cellular damage, and the molecular mechanisms of action. MTT assay, flow cytometry, fluorescence microplate assay, HPLC, qRT-PCR, and western blot were performed to analyze cytotoxicity, cell cycle, reactive oxygen species (ROS), BaP diol-epoxidation (BPDE)-DNA adducts, gene expression, and protein expression, respectively. Curcumin or VE prevented cells from BaP-induced cell cycle arrest and growth inhibition, significantly suppressed BaP-induced ROS levels, and decreased BPDE-DNA adducts. While CYP1A1 and 1B1 were induced by BaP, these inductions were not significantly reduced by curcumin or VE. Moreover, the level of activated p53 and PARP-1 were significantly induced by BaP, whereas this induction was markedly reduced after curcumin and VE co-treatment. Survivin was significantly down-regulated by BaP, and curcumin significantly restored survivin expression in BaP-exposed cells. The ratio of Bax/Bcl-2 was also significantly increased in cells exposed to BaP and this increase was reversed by VE co-treatment. Taken together, BaP-induced cytotoxicity occurs through DNA damage, cell cycle arrest, ROS production, modulation of metabolizing enzymes, and the expression/activation of p53, PARP-1, survivin, and Bax/Bcl-2. Curcumin and VE could reverse some of these BaP-mediated alterations and therefore be effective natural compounds against the adverse effects of BaP in lung cells.

Formaldehyde (FA) is a well-known irritant, and it is suggested to increase the risk of immune diseases and cancer. The present study aimed to evaluate the distribution of major lymphocyte subsets and cytokine expression profiles in the peripheral blood of FA-exposed workers. A total of 118 FA-exposed workers and 79 controls were enrolled in the study. High performance liquid chromatography, flow cytometry, and cytometric bead array were used to analyze FA in air sample and formic acid in urine, blood lymphocyte subpopulations, and serum cytokines, respectively. The FA-exposed workers were divided into low and high exposure groups according to their exposure levels. The results showed that both the low and high FA-exposed groups had a significant increase of formic acid in urine when compared to the controls. Both the low and high exposure groups had a significant increase in the percentage of B cells (CD19+) compared to the control group (p

Estrogen receptor (ER) is a nuclear receptor and the insulin-like growth factor-I (IGF-I) receptor (IGF-IR) is a transmembrane tyrosine kinase receptor. Estrogen and IGF-I are known to have synergistic effects on the growth of breast cancer cells. Recently, non-nuclear effects of ER have been under investigation. To study the mechanism involved in this process, we have used MCF-7 breast cancer cell lines transfected with IGF-IR anti-sense cDNA (SX13, MCF-7(SX13)) that resulted in 50% reduction of IGF-IR. In MCF-7 cells, estradiol (E2) and IGF-I induced the rapid association of ER to IGF-IR, however, the interaction was abrogated in MCF-7(SX13) cells. In addition, NWTB3 cells (NIH3T3 cells overexpressing IGF-IR) were transiently transfected with ERα, the ER-IGF-IR interaction was induced by both E2 and IGF-I. Moreover, ERα regulated the IGF-I signaling pathways through phosphorylation of ERK1/2 and Akt and the interaction of ER-IGF-IR potentiated the cell growth. Finally, E2 and IGF-I stimulated translocation of ER from the nucleus to the cytoplasm. Taken together, these findings reveal that the interaction of the ER and IGF-IR is important for the non-genomic effects of ER.

Beneficial effects of green tea polyphenols (GTP) against obesity have been reported, however, the mechanism of this protection is not clear. Therefore, the objective of this study was to identify GTP-targeted genes in obesity using the high-fat-diet-induced obese rat model. A total of three groups (n = 12/group) of Sprague Dawley (SD) female rats were tested, including the control group (rats fed with low-fat diet), the HF group (rats fed with high-fat diet), and the HF+GTP group (rats fed with high-fat diet and GTP in drinking water). The HF group increased body weight as compared to the control group. Supplementation of GTP in the drinking water in the HF+GTP group reduced body weight as compared to the HF group. RNA from liver samples was extracted for gene expression analysis. A total of eighty-four genes related to obesity were analyzed using PCR array. Compared to the rats in the control group, the rats in the HF group had the expression levels of 12 genes with significant changes, including 3 orexigenic genes (Agrp, Ghrl, and Nr3c1); 7 anorectic genes (Apoa4, Cntf, Ghr, IL-1β, Ins1, Lepr, and Sort); and 2 genes that relate to energy expenditure (Adcyap1r1 and Adrb1). Intriguingly, the HF+GTP group restored the expression levels of these genes in the high-fat-induced obese rats. The protein expression levels of IL-1β and IL-6 in the serum samples from the control, HF, and HF+GTP groups confirmed the results of gene expression. Furthermore, the protein expression levels of superoxide dismutase-1 (SOD1) and catechol-O-methyltransferase (COMT) also showed GTP-regulated protective changes in this obese rat model. Collectively, this study revealed the beneficial effects of GTP on body weight via regulating obesity-related genes, anti-inflammation, anti-oxidant capacity, and estrogen-related actions in high-fat-induced obese rats.

The development of novel targeted therapies has become an important research focus for lung cancer treatment. Our previous study has shown leptomycin B (LMB) significantly inhibited proliferation of lung cancer cells; however, p53 wild type lung cancer cells were resistant to LMB. Therefore, the objective of this study was to develop and evaluate a novel therapeutic strategy to sensitize LMB-resistant lung cancer cells by combining LMB and doxorubicin (DOX). Among the different treatment regimens, pretreatment with DOX (pre-DOX) and subsequent treatment with LMB to A549 cells significantly decreased the 50% inhibitory concentration (IC50) as compared to that of LMB alone (4.4 nM vs. 10.6 nM, P