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Introduction: Neuroinflammation contributes to secondary injury after traumatic brain injury (TBI), which has been mainly mediated by the microglia. MiR-124 was reported to play an important role in the polarization of microglia by targeting TLR4 signaling pathway. However, the role and mechanism of miR-124 in neuroinflammation mediated by microglia after TBI is unclear. To clarify this, we performed this research. Methods: The expression of miR-124 was first measured by RT-PCR in the injured brain at 1/3/7 days post-TBI. Then, miR-124 mimics or inhibitors administration was used to interfere the expression of miR-124 at 24 h post-TBI. Subsequently, the microglia polarization markers were detected by RT-PCR, the expression of inflammatory cytokines was detected by ELISA, the expression of TLR4/MyD88/IRAK1/TRAF6/NF-κB was measured by WB, and the neurological deficit was evaluated by NSS and MWM test. At last, in vitro experiments were performed to explore the exact target molecule of miR-124 on TLR4 signaling pathway. Results: Animal research indicated that the expression of miR-124 was downregulated after TBI. Upregulation of miR-124 promoted the M2 polarization of microglia and inhibited the activity of TLR4 pathway, as well as reduced neuroinflammation and neurological deficit after TBI. In vitro experiments indicated that miR-124 promoted the M2 polarization of microglia and reduced neuroinflammation by inhibiting TRAF6. Conclusion: This study demonstrated that upregulation of miR-124 promoted the M2 polarization of microglia and reduced neuroinflammation after TBI by inhibiting TRAF6.

The HIsarna process is a new and breakthrough smelting reduction process for hot metal (liquid iron) production from iron ores and coal directly fed into the reactor. The flue gas from the main reactor enters the off-gas system containing small amounts of H2, CO and carbon particles which need to be removed before further treatment by post combustion oxygen injection. A three-dimensional Computational Fluid Dynamics (CFD) simulation of the HIsarna off-gas system is performed and validated using a detailed reaction mechanism and kinetic data for post-combustion of a CO–H2 mixture and carbon particles. Using the validated model, a series of simulations were performed to investigate the effect of water quenching and post combustion oxygen injection. It was found that water quenching can significantly reduce the off-gas temperature. It is also possible to reduce oxygen injection during operations where inlet CO content of the off-gas system is low.

A three-dimensional computational fluid dynamics (CFD) model for the HIsarna off-gas system is set up and validated by real plant data. In the model detailed reaction mechanism and kinetic data for post-combustion of CO-H2 mixture and carbon particles are incorporated. The results are presented and discussed in another study (Part 1) by the same authors. In the present paper, the focus will be on geometry modification of the off-gas system and the effects on the operating parameters. The effect of this modification on heat loss, temperature profile, carbon conversion and gaseous phase composition across the off-gas system is investigated. It is shown that the modified geometry leads to a higher heat loss through the reflux chamber walls which can change the temperature profile and consequently species composition. The modified geometry also offers possibility of higher CO-H2 mixture and carbon particles conversion rate and reduce unwanted emission from the reflux chamber.

In this paper a CFD analysis of HIsarna off-gas system for post combustion of CO-H2-carbon particle mixture is presented to evaluate the effect of different sub-models and parameters on the accuracy of predictions and simulation time. The effects of different mesh type, mesh grid size, radiation models, turbulent models, kinetic mechanism, turbulence chemistry interaction models, including and excluding gas-solid reactions, number of reactive solid particles are investigated in detail. Based on the accuracy of the predictions and agreement with counterpart measured values, the best combination is selected and conclusions are derived. It was found that radiation and turbulence chemistry interaction model have a major effect on the temperature and composition profile prediction along the studied off-gas system, compared to the variations in other models. The effect of these two models becomes even more evident when the temperature and fuel content of the flue gas are high.

The environmental benefits of low-carbon technologies, such as photovoltaic modules, have been under debate because their large-scale deployment will require a drastic increase in metal production. This is of concern because higher metal demand may induce ore grade decline and can thereby further intensify the environmental footprint of metal supply. To account for this interlinkage known as the “energy-resource nexus”, energy and metal supply scenarios need to be assessed in conjunction. We investigate the trends of future impacts of metal supplies and low-carbon technologies, considering both metal and electricity supply scenarios. We develop metal supply scenarios for copper, nickel, zinc, and lead, extending previous work. Our scenarios consider developments such as ore grade decline, energy-efficiency improvements, and secondary production shares. We also include two future electricity supply scenarios from the IMAGE model using a recently published methodology. Both scenarios are incorporated into the background database of ecoinvent to realize an integrated modeling approach, that is, future metal supply chains make use of future electricity and vice versa. We find that impacts of the modeled metal supplies and low-carbon technologies may decrease in the future. Key drivers for impact reductions are the electricity transition and increasing secondary production shares. Considering both metal and electricity scenarios has proven valuable because they drive impact reductions in different categories, namely human toxicity (up to −43%) and climate change (up to −63%), respectively. Thus, compensating for lower ore grades and reducing impacts beyond climate change requires both greener electricity and also sustainable metal supply. This article met the requirements for a Gold-Gold JIE data openness badge described at http://jie.click/badges.

Suspension reduction kinetics of hematite ore particles at 1710 K to 1785 K was described by the Johnson-Mehl-Avrami-Kolmogorov model with Avrami exponent of 1.405. The apparent activation energy is 105.5 kJ mol−1 with the rate determining step of nucleation and growth. The reduction degree of the hematite at the endpoint is a linear function of temperature and the logarithmic oxygen potential of the reacting gas. A peak function of reaction rate constant with particle size has been verified in this work, and the maximum value of the reaction rate is located at around 85 µm particle size. The influence of heat transfer on the reaction process has been evaluated. The results suggest that the heating-up process for large particles, 244 µm particles, for instance, cannot be ignored. It can retard the reaction rate compared to small particles. Normally, the reaction rate constant decreases linearly with the increase of ln[p(O2)] of the reacting gas mixture. However, 95 vol pct CO2 in the reacting gas can accelerate the reaction rate of thermal decomposition of hematite due to the emissivity of CO2 gas. It results in a higher reaction rate of 110 µm particles in 95 vol pct CO2-containing gas than that in other less CO2-containing gases.

In order to understand the pre-reduction behaviour of fine hematite particles in the HIsarna process, change of morphology, phase and crystallography during the reduction were investigated in the high temperature drop tube furnace. Polycrystalline magnetite shell formed within 200 ms during the reduction. The grain size of the magnetite is in the order of magnitude of 10 µm. Lath magnetite was observed in the partly reduced samples. The grain boundary of magnetite was reduced to molten FeO firstly, and then the particle turned to be a droplet. The Johnson-Mehl-Avrami-Kolmogorov model is proposed to describe the kinetics of the reduction process. Both bulk and surface nucleation occurred during the reduction, which leads to the effect of size on the reduction rate in the nucleation and growth process. As a result, the reduction rate constant of hematite particles increases with the increasing particle size until 85 µm. It then decreases with a reciprocal relationship of the particle size above 85 µm.

Electrorefining effectively separates metals from their corresponding alloys. To obtain Nd from Cu6Nd alloy, cyclic voltammetry and square wave voltammetry were used to investigate the reduction behavior of Nd3+ and the anode dissolution behavior of Cu6Nd in the NaCl–KCl–0.5mol%NdCl3 melt at 1023 K. According to the analysis of the electrochemical behavior, the cell voltage was determined to be between 0.3 and 1.2 V for separating Nd from Cu6Nd. After electrolysis at 0.6 V for 4 h, the Nd was found at the surface of the Mo cathode without any Cu. For the Fe cathode, a deposition with an atom ratio of Nd: Fe = 1:1 was formed on the surface. However, the low current density of separation remains a great experimental challenge that must be solved.

It was not clear how and whether neural stem cells (NSCs) responded to toll-like receptor 2 (TLR2) in the inflammatory environment after traumatic brain injury (TBI). The current study investigated the correlation of TLR2 and NSC proliferation in the dentate gyrus (DG) using the TBI model of rats. Immunofluorescence (IF) was used to observe the expression of BrdU, nestin, and TLR2 in the DG in morphology. Proliferating cells in the DG were labelled by thymidine analog 5-bromo-2-deoxyuridine (BrdU). Three-labelled BrdU, nestin, and DAPI was used for the identification of newly generated NSCs. Western blotting and real-time polymerase chain reaction (PCR) were used to observe the expression of TLR2 from the level of protein and mRNA. We observed that BrdU+/nestin+/DAPI+ cells accounted for 84.30%±6.54% among BrdU+ cells; BrdU+ and nestin+ cells in the DG were also TLR2+ cells. BrdU+ cells and the expression of TLR2 (both protein and mRNA levels) both elevated immediately at 6 hours (h), 24 h, 3 days (d), and 7 d posttrauma and peaked in 3 d. Results indicated that TLR2 was expressed on proliferating cells in the DG (NSCs possibly) and there was a potential correlation between increased TLR2 and proliferated NSCs after TBI. Taken together, these findings suggested that TLR2 was involved in endogenous neurogenesis in the DG after TBI.

To lower the iron losses of the hot metal desulphurisation (HMD) process, slag modifiers can be added to the slag. Slag modifiers decrease the apparent viscosity of the HMD slag. Most common slag modifiers in industry contain fluoride as a fluidiser. However, fluoride leads to a higher magnesium consumption and has health, safety and environment issues. Fluoride-free alternatives like nepheline syenite (NS) and fly ash (or pulverised fuel ash, PFA) can decrease the slag’s apparent viscosity. Experiments with HMD slags containing CaF2, NS and PFA and without slag modifier were performed for slags with a high and an average basicity. The melting points of the slags and their viscosities 1250–1600°C were measured. The experimental results are compared with FactSage calculations. PFA and NS are viable alternatives in the industrial HMD process, as reasonable amounts are sufficient to reach the same lower apparent viscosities and melting points as with CaF2.

Purpose Hepatocellular carcinoma (HCC) has a high incidence in China and exploring effective ways for early diagnosis is an important method to improve the prognosis of patients with HCC. Additional studies reported that. Some kinds of microRNA (miRNA) in plasma will change accordingly during HCC progress, and this change can be used to diagnose HCC, especially with miRNA-122, miRNA-21 and miRNA-96. We were aiming at investigating the values of the exosomal miRNAs in diagnosis and prognosis for HCC patients. Patients and methods Blood samples from 50 patients with HCC and 50 patients with hepatic cirrhosis and 50 healthy volunteers were obtained. The diagnostic accuracy of the plasma and exosomal miRNAs and the comparisons among different groups were measured by the area under the curve (AUC) on receiver operating characteristic (ROC) curve analysis. Results Expression levels of miRNA-21 and miRNA-96 were significantly higher in patients with HCC and of miRNA-122 were significantly lower in HCC compared with cirrhotic patients in both exosomes and plasma. Among different groups, exosomal miRNA-122, miRNA-21 and miRNA-96 were significantly more accurate in diagnosing HCC than those miRNAs in plasma and the alpha-fetoprotein (AFP) level. The miRNA panel had high accuracy in discriminating HCC from the cirrhosis group (AUC 0.924; 95% CI; sensitivity 82%, specificity 92%) and healthy volunteers' group. Exosomal miRNA-21 and miRNA-96 with low expression and miRNA-122 with high expression could be associated with a patient's survival time. However, the miRNA panel could better predict the HCC patient's survival time compared with each miRNA individually. Conclusion This study showed that the expression levels of miRNA-122, miRNA-21 and miRNA-96 in exosomes were more significantly changed than those miRNAs in plasma in patients with HCC compared with cirrhotic patients, and the exosomal miRNA panel containing miRNA-122, miRNA-21 and miRNA-96 could be defined as a diagnostic biomarker for patients with HCC. We also conclude that different expression of exosomal miRNAs, especially the miRNA panel, could predict the HCC patient's prognosis.

An innovative electroslag remelting furnace with a water-cooled electrode was introduced to recycle the rejected electrolytic manganese metal (EMM) scrap. To clarify the desulfurization process in the rejected EMM scrap, a transient three-dimensional comprehensive numerical model was elaborated. Using the magnetic potential vector approach, the respective electromagnetic fields were calculated via the Maxwell equations. The Lorentz force and the Joule heating fields were derived as phase distribution functions and interrelated via the momentum and energy conservation equations as source terms, respectively. The molten manganese metal droplet motion, as well as the fluctuation of the slag–metal interface, was described by the volume-of-fluid (VOF) approach. Besides, the solidification was modeled via the enthalpy-based technique. A thermodynamic module was established to estimate the sulfur mass transfer rate between the molten manganese metal and the molten slag. Furthermore, a factor related to the magnitude and frequency of the alternating current and the physical properties of the melt was introduced to include the electro-emulsification phenomenon. An experiment has been carried out with a commercial-scale ESR device. The predicted values of the slag temperature and sulfur content in the final manganese ingot were found to agree reasonably with the corresponding measured data. Under continuous melting of the rejected EMM scrap, molten manganese metal droplets are formed at the domain inlet, grow, and fall down. Highly conductive molten manganese metal droplets significantly change distributions of the current streamline, the Joule heating, and the Lorentz force around and within it. Moreover, droplets are inclined to rotate and move inside the mold. With the renewal of the slag–manganese interface, sulfur in the molten manganese metal is constantly transferred to the molten slag. With the applied current ranging from 3000 to 4000 A, the average sulfur content of the manganese ingot dropped from 0.0447 to 0.0291 pct, and thus, the desulfurization rate rose from 55.3 to 70.9 pct.

Galvanized steel scrap flow and injection into the HIsarna reactor are investigated using discrete element method (DEM). The scrap particle is fed into the reactor through an inclined chute and hits the slag surface where the zinc content is evaporated and solid particles melt. A DEM model is setup and validated using experimental data obtained from the exact plant-scale chute geometry and scrap particles. Using the DEM model, the effect of chute inclination, injection elevation, injection mode (batch and continuous), batch size, and flowrate on particle distribution and exerted pressure on the slag surface are investigated. It is found that continuous mode of injection is the most suitable method to increase the spread of particles and also to reduce the exerted pressure on the slag surface. Placing dent-like obstacles at the tip of the chute significantly increases the impact area, especially for batchwise injection, thus reducing force and pressure on the slag surface that minimizes the risk of liquid splash. Larger particle impact area is also beneficial to obtain higher zinc evaporation rate from particle surface and also to minimize the slag surface temperature disturbance.

HIsarna reactor is characterized by a high raw materials versatility and is therefore attractive for processing secondary iron sources. Among the materials that can be recycled through HIsarna, zinc-bearing material has drawn a special attention. Based on the plant data, once dust-containing Zinc was injected into the main reactor, a final collected dust with a zinc content of 16% was achieved which opened up possibilities of higher enrichment for direct reuse in Zn smelting as a secondary source and an alternative for Zn ore (the primary source). However Zn vapor can react with iron oxide to form zinc ferrite (ZnFe2O4), which is an undesired product. Hence, the main focus of this study is to minimize the formation of ZnFe2O using thermodynamic (FactSage) and computational fluid dynamic tools. After detecting regions with high potential of ZnFe2O4 formation, proper geometrical and operational modifications of the off-gas system is proposed to minimize the formation of zinc ferrite.

Objective: Myocardial injury is a severe complication in population exposed to high altitude. As a new biomarker for inflammatory response, neutrophil to lymphocyte ratio (NLR) has been widely used to predict the prognosis of various diseases. In this study, we intend to explore the risk factors for myocardial injury at high altitude and examine the relationship between NLR level and development of myocardial injury.Methods: Consecutive patients admitted to a secondary general hospital at high altitude from June 2019 to May 2020 were selected into this retrospective study. Clinical and biochemical data were collected. According to the results of lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase isoenzymes (CK-MB), and aspartate amino transferase (AST), patients were divided into myocardial injury group and normal group.Results: A total of 476 patients were enrolled in this study. Myocardial injury occurred in 158 patients (33.2%). We found that altitude, NLR, hemoglobin, total bilirubin, total cholesterol, and lipoprotein A in myocardial injury group were significantly higher than that in normal group (P < 0.05), while platelet count in myocardial injury group was significantly lower than that in normal group (P < 0.05). Logistic multivariate regression analysis revealed that there was an independent relationship between myocardial injury and smoke, NLR, hemoglobin (P < 0.05). By using Spearman correlation analysis, NLR was proved to have a significant positive correlation with LDH, CK, and CK-MB (P < 0.05) instead of AST. A receiver operating characteristic (ROC) curve was drawn to demonstrate that NLR could significantly predict the occurrence of myocardial injury with an area under the curve (AUC) of 0.594 (95% CI: 0.537–0.650, P < 0.05), and the level of 2.967 (sensitivity = 38.0%, specificity = 83.6%) was optimal cutoff value.Conclusion: The incidence of myocardial injury is high in population at high altitude. Smoke, hemoglobin, and NLR are independent factors related to myocardial injury. As a convenient and efficient marker, NLR is found to be closely associated with myocardial enzymes and have a predict role in the occurrence of myocardial injury. This study will provide a theoretical basis on NLR for the early diagnosis of myocardial injury at high altitude.

Due to the limited neurogenesis capacity, there has been a big challenge in better recovery from neurological dysfunction caused by stroke for a long time. Neural stem cell (NSC) programmed death is one of the unfavorable factors for neural regeneration after stroke. The types of death such as apoptosis and necroptosis have been deeply investigated while the pyroptosis of NSCs is not quite understood. Although it is well accepted that hyperbaric oxygen (HBO) alleviates the oxygen-glucose deprivation (OGD) injury after stroke and reduces programmed death of NSCs, whether NSC pyroptosis is involved in this process is still unknown. Therefore, this study is aimed at studying the potential effect of HBO treatment on NSC pyroptosis following OGD exposure, as well as its influence on NSC proliferation and differentiation in vitro. The results revealed that OGD increased NOD-like receptor protein 3 (NLRP3) expression to induce the pyroptotic death of NSCs, which was rescued by HBO treatment. And the upregulated lncRNA-H19 functioned as a molecular sponge of miR-423-5p to target NLRP3 for NSC pyroptosis following OGD. Most importantly, it was confirmed that HBO exerted protection of NSCs against pyroptosis by inhibiting lncRNA-H19/miR-423-5p/NLRP3 axis. Moreover, HBO restraint of lncRNA-H19-associated pyroptosis benefited the proliferation and neuronal differentiation of NSCs. It was concluded that HBO attenuated NSC pyroptosis via lncRNA-H19/miR-423-5p/NLRP3 axis and enhanced neurogenesis following OGD. The findings provide new insight into NSC programmed death and enlighten therapeutic strategy after stroke.

The effect of high-altitude (HA) on venous thromboembolism (VTE) and its mechanism remains ambiguous. To clarify this, we aimed to conduct a meta-analysis and systematic review to evaluate the incidence of VTE at HA and comparatively low altitude (LA) and figure out the intrinsic risk factors such as susceptibility genes of patients with VTE at HA.We selected studies that explored the risk factors for HA and VTE by searching PubMed, Embase, and Web of Science to analyze the impact of HA on VTE. All relevant studies before August 2021 were screened using the terms ([high altitude] OR [plateau] OR [mountain]) AND ([venous thromboembolism] OR [deep vein thrombosis] OR [pulmonary embolism]). Latest studies on the gene of HA-VTE patients were also summarized and analyzed.Fifteen studies were eventually assessed, and the overall numbers of subjects with and without VTE were 1475 and 286,926 respectively. The overall incidence of VTE, deep vein thrombosis (DVT) and pulmonary embolism (PE) in the HA group was significantly higher than that in the LA group (P0.01). The overall incidence of VTE, DVT and PE in the HA group was significantly higher than that in the LA group at 30 days post operation (P0.05, P0.05 and P0.01, respectively). At 90 days post operation, incidence of VTE and PE in the HA group was higher than that in the LA group (P0.01and P0.01, respectively), but there was no difference in the incidence of DVT (P = 0.07). Regarding endogenous factors, the analysis of genes in patients with HA-VTE revealed numerous targeted genes such as ANG, ACE, lncRNA-LINC00 659/UXT-AS1 and GP4.We observed a significant association between HA and the overall incidence of VTE and that at 30/90 days post operation, indicating that HA may be a risk factor for VTE.

Electrolytic production of metallic neodymium is carried out in fused neodymium fluoride salts containing neodymium oxide. Two major challenges pertaining to neodymium production in fluoride salts are a) low solubility of neodymium oxide in fluoride melt, b) possibility of anodic gas evolution (CO, CO2, CF4, C2F6). In this study, iron is used as a reactive anode in the electrolysis process, promoting electrochemical dissolution of iron into the melt, preventing PFC (perfluorocarbon) gas evolution at the anode. Further, the rare earth oxide is converted to rare earth fluoride by the use of iron fluoride formed as the result of iron dissolution. Thus, the fluoridizing agent is constantly regenerated in-situ which enables the continuous conversion of neodymium oxide feed. The cathodic product is Nd Fe alloy which can be used as a master alloy for the production of NdFeB magnets.

In this work, a novel low-cost and robust approach is developed to covert Ti-bearing blast furnace slag (Ti-slag) to the main feed stock of photoassisted NH3 selective catalytic reduction (Photo NH...

In order to recognize the dripping and the carburizing behaviors of the molten iron within the coke packed bed in the flash ironmaking process, a transient three-dimensional numerical model was developed. The volume of fluid (VOF) approach is used to describe the movement of the molten iron and the argon gas. The porous medium module is employed to define the momentum, heat, and mass transfer between the coke packed bed and the molten iron. Moreover, a factor is introduced to consider the influence of the ash film on the carburization process. A reasonable agreement between the experiment and simulation is obtained. The results indicate that the molten iron flows downward from the upper crucible to middle crucible. After entering the middle crucible, the molten iron spreads around within the coke packed bed and simultaneously moves downward. The carbon is, therefore, transferred from the coke to the molten iron. With the 47-mm-height coke packed bed, the carbon content in the molten iron after the carburization decreases from 3.19 to 1.97 pct, while the coke diameter ranges from 2 to 5 mm. With the 2-mm-diameter coke, the carbon content in the molten iron after the carburization increases from 2.84 to 4.81 pct, while the coke packed bed height increases from 37 to 97 mm.

The leaching characteristics and mechanism of synthetic CaO-Al 2 O 3 slags in alkaline solution at atmospheric pressure have been studied. The purpose of the study is to have a better understanding of the leaching part of the Pedersen process, as an alternative to the Bayer process for alumina production. The crystalline slags containing CaAl 2 O 4 , Ca 3 Al 2 O 6 , CaAl 4 O 7 , and Ca 12 Al 14 O 33 phases, and leaching residues (predominantly CaCO 3 ) are characterized by X-ray Diffraction and semi-quantitative analysis. Of the leaching characteristics in a solution containing 120 g/L Na 2 CO 3 , the slag with the highest amount of Ca 12 Al 14 O 33 phase is the most leachable one in the CaO-Al 2 O 3 system with about 95% of alumina extraction. The leaching extent is confirmed employing Inductively Coupled Plasma-High Resolution-Mass Spectrometer (ICP-HR-MS) analysis, and it decreases by 0.4% for every percent of the bayerite (Al(OH) 3 ) formation during the leaching. The less stable form of CaCO 3 , i.e., vaterite, is formed over the leached slag particles that consist 33–49 wt% CaO, while Ca 3 Al 2 (OH) 12 (tricalcium alumina hydrate) precipitated at relatively low concentrations (< 6 wt%) in all residue. The non-bridging oxygen (NBO) over tetrahedral structure (T) index shows that the atomic structure may affect the leaching extent of the slags, the lower NBO/T index of the phase is the more difficult for the phase to leach or depolymerize. However, the Ca 12 Al 14 O 33 phase is an exception case where it has “free” O-ions at the center of the cage structure, which makes it easily depolymerize, therefore, the NBO/T index for the Ca 12 Al 14 O 33 phase becomes irrelevant. Furthermore, the morphology and size evolution of the obtained residue measured with laser particle analyzer indicates the agglomeration behavior of the residue particles during the leaching process.

HIsarna is a promising ironmaking technology to reduce CO 2 emission. Information of phase transformation is essential for reaction analysis of the cyclone reactor of the HIsarna process. In addition, data of density and volume of the ore particles are necessary for estimation of the residence time of the particles in the cyclone reactor. Phase transformation of iron ore particles was experimentally studied in a drop-tube furnace under simulated cyclone conditions and compared with thermodynamic calculation. During the pre-reduction process inside the reactor, the mineralogy of iron ore particles transforms sequentially from hematite to sub-oxides. The density changes of the particles during the melting and reduction can be predicted based on the phase composition and temperature. Therefore, density models in the studies were evaluated with reported experimental data of slag. As a result, a more reliable density model was developed to calculate the density of the formed slag containing mainly FeO–Fe 2 O 3 . The density and volume of the partially reduced ore particles or melt droplets were estimated based on this model. The results show that the density of the ore particles decreases by 15.1% at most along the progressive reduction process. Furthermore, the model results also indicate that heating, melting and reduction of the ore could lead to 6.63–9.37% swelling of the particles, which is mostly contributed by thermal expansion. It would result in corresponding variation in velocity of the ore particles or melt droplets during the flight inside the reactor.

High-temperature reduction processes of iron oxide particles suspension are promising in carbon emission abatement. Recently, researchers have contributed abundant knowledge of the reaction mechani...

MicroRNA-124 (miR-124) is a brain specific miRNA that is highly expressed in microglia. The upregulation of miR-124 contributes to M2 polarization of microglia, which is beneficial to neurogenesis. Exosomes are lipid membrane vesicles that can deliver miR-124 into the brain. However, whether miR-124 enriched exosomes (Exo-miR-124) can regulate the polarization of microglia and affect hippocampus neurogenesis after traumatic brain injury (TBI) is unknown. To clarify this, the Exo-miR-124 was first constructed, and then was intravenously administrated into rats via tail vein with the dose of 3 × 109 particles/each rat at 24 h post TBI. The polarization of microglia in hippocampus was evaluated through measuring the signature genes and cytokines of M1/M2 phenotype by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immune sorbent assay (ELISA) at 7/14/21/28 days after TBI. Hippocampus neurogenesis was evaluated through detecting the proliferation marker BrdU/SOX2 and differentiation marker BrdU/NeuN by immunofluorescence (IF) at 7 and 28 days after TBI respectively. Neurological function was evaluated by neurological severity score (NSS) and morris water maze (MWM) at 7/14/21/28 and 24–28 days after TBI respectively. To explore the underlying mechanisms, the mRNA expression of TLR4 pathway molecules in hippocampus were measured by RT-PCR, and the polarization of microglia and the activation of TLR4 pathway in BV2 cells were measured after exosome treatment as well. Results demonstrated that Exo-miR-124 treatment promoted the M2 polarization of microglia, enhanced neurogenesis in hippocampus, and improved function recovery after TBI. The M2 polarization effect of Exo-miR-124 was produced through inhibiting TLR4 pathway, which was verified in hippocampus and BV2 microglia. In conclusion, Exo-miR-124 treatment promoted M2 polarization of microglia and improved hippocampal neurogenesis and functional recovery after brain injury, which might be a strategy to improve the outcome of TBI.

Objective: Traumatic brain injury (TBI) induces immunosuppression in the acute phase, and the activation of the sympathetic nervous system (SNS) might play a role in this process, but the mechanism involved is unknown. Herein, we explored the impact of acute (a)TBI on the peripheral immune system and its correlation with the SNS and the T cell exhaustion marker, PD-1 (programmed cell death-1). Methods: Flow cytometry (FCM) was performed to analyze the expression of T cell markers and intracellular cytokines, interferon-γ and tumor necrosis factor-α, and the T cell exhaustion marker, PD-1, in the peripheral blood mononuclear cells (PBMCs) of TBI rats. Enzyme-linked immunosorbent assay (ELISA) was performed to analyze the concentration of norepinephrine (NE) in the serum. Propranolol was administrated to block the SNS in vivo and NE stimulation was used to imitate the activation of the SNS in vitro. Results: We found that the concentration of NE was significantly elevated after TBI, and the dysfunction of CD4+ and CD8+ T cells was reversed by the SNS blocker propranolol in vivo and imitated by the SNS neurotransmitter NE in vitro. The expression of PD-1 on CD4+ and CD8+ T cells was upregulated after aTBI, which was reversed by propranolol administration in vivo and imitated by NE stimulation in vitro. Furthermore, the PD-1 blocker reversed the dysfunction of CD4+ and CD8+T cells in vitro. Conclusion: Our findings demonstrated that aTBI activated the SNS, and further upregulated the expression of PD-1 on CD4+ and CD8+ T cells, which, in turn, impaired their function and contributed to immunosuppression.

In hot metal desulphurisation (HMD) the slag will hold the removed sulphur. However, the iron that is lost when the slag is skimmed off, accounts for the highest costs of the HMD process. These iron losses are lower when the slag has a lower viscosity, which can be achieved by changing the slag composition. A lower slag basicity decreases the viscosity of the slag, but also lowers its sulphur removal capacity, therefore optimisation is necessary. In this study, the optimal HMD slag composition is investigated, considering both the sulphur removal capacity and the iron losses. In part I the theory is discussed and in part II the optimal slag is validated with plant data, laboratory experiments and a thermodynamic analysis.

The optimal hot metal desulphurisation (HMD) slag is defined as a slag with a sufficient sulphur removal capacity and a low apparent viscosity (ηslag) which leads to low iron losses. In part I of this study, the fundamentals behind the optimal slag were discussed. In this part these fundamentals are explored by a Monte Carlo simulation, based on FactSage calculations, plant data analysis and melting point and viscosity measurements of the optimal slag. Furthermore, the applicability of knowing the optimal slag composition for an industrial HMD is discussed.

The circular economy demands waste utilization for the production of high-value products, and this requires the development of novel processing routes. In this study, rare earth (La and Ce) oxides were completely (>99%) recovered from polishing waste by a combined novel reductive acid leaching and alkali treatment process. About 70% of rare earths were dissolved during the first leaching step. The undissolved rare earth compounds are converted to oxides/hydroxides by alkali treatment and dissolved in the acid solution – the 2nd leaching step – for the complete recovery of rare earths. The recovered rare earth oxides were used for producing in-situ high-value Al-La-Ce alloys with fused salt electrolysis. Mechanical properties of our Al-La-Ce alloys are similar to the known high temperature Al-Ce alloys. This development of new alloys by our novel process helps in utilization of both overproduced primary La and Ce oxides as well as La and Ce recovered from polishing waste.

HIsarna is a novel ironmaking process with great raw materials versatility that is attractive for various secondary resources. Among the materials that can be recycled, there is steel scrap which is fed to the furnace bath through an inclined chute. The velocity distribution of the scrap particles along the chute affects the particles’ distribution on the liquid slag and, thereupon, the efficient operation of the reactor. In this study, the flow of steel scrap particles along an inclined chute with the same dimensions as those of the actual chute of the HIsarna plant is investigated experimentally and numerically. The simulations are validated using chute tip velocity and mass fractions collected at the different compartments of a sampling device. Translational and angular velocity distributions along and across the chute are reported, and the effect of different parameters are investigated. The impact of the shape of the particles on the simulation process is found to be negligible. The angular velocity distribution in cross-sections of the chute exhibited a V-shaped orientation, whereas the translational velocity displayed similar values across the cross-sections. Moreover, translational velocity appeared to increase with increasing inclination angles, whereas angular velocity increased with decreasing batch size.

Objective To explore the change of the expression of microRNA-124-3p (miR-124-3p) in injured hippocampus of rats and investigate the role of miR-124-3p in neuranagenesis after traumatic brain injury (TBI). Methods The healthy male rats were randomly divided into a sham-operated group, TBI group, miR-124-3p agomir group and miR-124-3p antagomir group. TBI models were constructed by controlled cortical injury (CCI) device for all the groups except for the sham-operated group. The miR-124-3p agomir (1 nmol) was given to the miR-124-3p agomir group and miR-124-3p antagomir (1 nmol) to the miR-124-3p antagomir group via lateral ventricular injection, and equivalent solvent was given to the sham-operated group and TBI group after injury. The injured hippocampus of rats was collected at 12 hours, 1 day, 3, 7 days after injury. The real-time PCR and Western blot analysis were used to examine the expression of miR-124-3p and Delta-like 1 (DLL1) in the injured hippocampus. Immunofluorescence histochemistry was used to examine the expression levels of 5-bromodeoxyuridine (BrdU), neuronal nuclear antigen (NeuN) and nestin in the injured hippocampus. Bioinformatics software was used to predict and dual luciferase reporter assay to validate the regulatory relationship between miR-124-3p and DLL1. Results The miR-124-3p and DLL1 expression in the TBI group were significantly higher than those in the sham-operated group; compared with the TBI group, the miR-124-3p agomir group had significantly increased expression of miR-124-3p and significantly decreased expression of DLL1 in the injured hippocampus, and miR-124-3p antagomir group had significantly decreased expression of miR-124-3p and significantly increased expression of DLL1. Compared with the sham-operated group, the BrdU