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Corrosion under insulation (CUI) is a crucial issue in the industry. Its importance has been increasingly acknowledged because of the high cost and potential danger of causing severe losses. This review gives essential knowledge of CUI and summarizes the research from several aspects, including lab experiments, field tests, CUI prediction methods and numerical simulation research in porous materials. Insulation material, coating, substrate metallic material of the equipment, operating temperature and surroundings are some critical factors that should be considered in the CUI problem. Experimental research methods of CUI and mass transfer in insulation materials were summarized, as well as the applications of data science in CUI prediction. This review also focuses on simulation researches on heat and moisture transfer in porous insulation materials since numerical simulations are helpful for establishing validated models for CUI by modeling to describe the specific processes and predict environmental conditions of CUI for further corrosion research. Combined experimental and simulation work of CUI would be a practical and effective method for CUI research.

C/C-BN composites and Cf/BN/PyC composites exhibiting different structures for pyrolytic carbon (PyC) and boron nitride (BN) were studied comparatively to determine their oxidation behavior. This study used five types of samples. Porous C/C composites were modified with silane coupling agents (APS) and then fully impregnated in water-based slurry of hexagonal boron nitride (h-BN); the resulting C/C-BN preforms were densified by depositing PyC by chemical vapor infiltration (CVI), resulting in three types of C/C-BN composites. The other two Cf/BN/PyC composites were obtained by depositing a BN interphase and PyC in carbon fiber preforms by CVI; one was treated with heat, and the other was not. This study was focused on determining how the PyC deposition mechanism, morphology and pore structure were affected by the method of BN introduction. In the 600–900 °C temperature range, the Cf/BN/PyC composites and C/C composites underwent oxidation via a mixed diffusion/reaction mode. The C/C-BN composites had a different pore structure due to the formation of nodules comprising h-BN particles; both interfacial debonding and cracking were reduced, resulting in higher resistance to gas diffusion, lower oxidation rate and larger activation energy (Ea) in the temperature range 600–800 °C. In addition, the mechanism for oxidation of C/C-BN composites gradually exhibited diffusion control at 800–900 °C because the formation of h-BN oxidation products healed the defects. The oxidation mechanism was more dependent on pore structure than on BN structure or content.

C/C-BN-SiC composite was prepared by ceramic slurry infiltration combined with resin impregnation and carbonization, and the matrix with continuous distributed self-healing phase was obtained. In this study, the kinetic characteristics and oxidation behavior of the composites with various h-BN/SiC ratios in the temperature range of 600∼1300°C were studied by combining the isothermal oxidation test with the kinetic model. The optimal h-BN/SiC ratio balances the thermal stability and fluidity of the oxidized product, which not only has high thermal stability and low oxygen permeability to acts as an oxygen diffusion barrier but also has a certain fluidity to seal defects.

Dinoflagellates are a diverse group of ecologically significant micro-eukaryotes, prone to the loss and replacement of their plastids via serial endosymbiosis. One such replacement took place in the ancestors of the Kareniaceae, which harbor haptophyte-derived plastids containing the pigment fucoxanthin, instead of the ancestral peridinin dinoflagellate plastid. The metabolic functions of the fucoxanthin plastid are performed by a diverse range of nucleus-encoded and plastid-targeted proteins, which may originate from the haptophyte ancestor of the fucoxanthin plastid, the peridinin-containing ancestor of the dinoflagellate host, and/or from lateral gene transfers. However, the evolutionary composition of fucoxanthin plastid proteomes across the diversity of kareniacean dinoflagellates remains poorly understood. Here, we determine the total composition of the plastid proteomes of seven distantly-related kareniacean dinoflagellates, including newly-sequenced members of three genera (Karenia, Karlodinium, andTakayama). Using a custom plastid-targeting predictor, automatic single-gene tree building and phylogenetic sorting of plastid-targeted proteins, we project relatively limited (~10%) and functionally distinctive contributions of the haptophyte endosymbiont to the fucoxanthin plastid proteome, in comparison to plastid-targeted proteins of dinoflagellate host origin. Considering a concatenated multigene phylogeny of haptophyte-derived plastid proteins, we show that the haptophyte order Chrysochromulinales is the closest living relative of the fucoxanthin plastid donor. We additionally perform detailed analyses of the N-terminal targeting sequences of kareniacean plastid signal peptides, reporting a surprisingly high sequence conservation. Finally, considering planetary-scale distributions of key kareniacean genera and haptophyte orders fromTaraOceans, we suggest ecological and mechanistic factors accompanying the endosymbiotic acquisition of the fucoxanthin plastid.

The oxygen supply process is a key operation in the metallurgy field, as it injects oxygen in addition to dynamic energy into the molten bath using an oxygen lance or a submerged nozzle. During the basic oxygen furnace (BOF) steelmaking process, the control process of the oxygen lance has a great influence on the slag melting, impact cavity shape, and chemical reaction rate. In this article, the preheating method has been used to further increase the initial velocity and impaction ability of supersonic multi-jets. A computational fluid dynamics model was built to investigate the behaviors of the generated supersonic oxygen multi-jets as per different oxygen preheating temperatures. Moreover, a series of experiments has been conducted to verify the reliability of the simulation results. The results showed that higher preheating temperatures significantly increased the initial axial velocity of the oxygen jet at the Laval nozzle exit and that they accelerated the downtrend of the oxygen jet velocity because of the more obvious entrainment phenomenon among the oxygen multi-jets. In addition, it was found that higher preheating temperatures only resulted in limited improvements on the impact area, but they reduced the oxygen utilization rate at high ambient temperatures.

In this study, with 2.5D needle punched carbon felt as reinforcement, hexagonal boron nitride (h-BN) was introduced through chemical vapor infiltration (CVI) and slurry impregnation (SI) methods, and then pyrocarbon was deposited through CVI to convert the BN-containing preform into carbon fiber reinforced carbon-boron nitride binary matrix composites (C/C-BN). The microstructure and mechanical properties of C/C-BN(P) composites prepared by SI combined with CVI were compared with those of C/C-BN(CVI) composites prepared by CVI. The tribological behavior of C/C-BN(P) composites containing different contents of h-BN fillers and C/C-BN(CVI) composites with and without heat treatment was investigated by the ball-on-disk technique in dry sliding conditions using GCr15 steel balls and Si3N4 balls as sliding counterparts at two different sliding speeds (v = 0.2 and 0.8 m/s), and compared with the C/C composites used as a reference. C/C-BN(P) composites exhibit improved tribological behavior, which can be explained by the combined effect of SI and CVI on the microstructure and mechanical properties, leading to changes in the wear mechanism of the C/C-BN composites. The excellent reinforcement is attributed to the integrity structure of the C/C-BN(P), which can make the self-lubricating friction layer stably exist on the surface of the material and significantly reduce the friction coefficient and wear loss of the C/C-BN(P) composite. Furthermore, the mechanical and tribological properties of C/C-BN(P) composites can be adjusted by using different volume content of h-BN. The present work shows that C/C-BN(P) composites have wide application prospects as anti-friction and wear-resistant materials.

An intramolecular anaerobic Mukaiyama hydration-initiated tandem reduction/condensation/acyl migration/aromatization reaction was developed, which enabled the rapid construction of indole-fused 8-10 membered lactones starting from cyclic 2-allyl-2-(2-nitrophenyl)-1,3-diketones. A nitro substituent in the substrates acted as both an oxygen source in the Mukaiyama hydration step and a nitrogen source in a tandem indole ring construction step. Our reaction features mild conditions, atom economy, and inexpensive reagents and it can be conveniently scaled up to a gram scale in modest yields. A rational reaction mechanism was also proposed based on previous reports and control experiments.

A low-density carbon/carbon (C/C) composite/silane coupling agent/hexagonal boron nitride (h-BN) hybrid reinforcement was prepared by grafting polyethyleneimine (PEI)-encapsulated modified h-BN fillers onto a carbon fiber surface using 3-aminopropyltriethoxysilane (APS) as the connection to improve the distribution uniformity of h-BN fillers in quasi-three-dimensional reinforcements and the interfacial properties between the fibers/pyrocarbon (PyC) in the C/C-BN composites obtained after densification by chemical vapor infiltration (CVI). The microstructure and chemical components of the hybrid reinforcement were investigated. The transmission electron microscopy (TEM) sample was prepared using a focused-ion beam (FIB) for the h-BN/PyC interfacial zone. The interlaminar shear strength (ILSS) and impact toughness were analyzed to inspect the composites’ interfacial properties. The results show that APS and h-BN are uniformly grafted on the fiber surface in the chopped fiber web inside the C/C composite without a density gradient, and agglomeration occurred and significantly increasing the fiber surface roughness. The highly ordered h-BN basal plane may affect the order degree of PyC near the h-BN/PyC interface. The addition of h-BN reduces the PyC texture near it, causing the annular cracks to disappear gradually. The lower PyC texture and the rougher fiber surface strengthen the interfacial bond of the fiber/matrix. Consequently, the ILSS strength of the C/C-BN composites first increases and then decreases as the h-BN filler content increases and is always higher than that of the C/C composite, while the addition of h-BN fillers weakens its impact toughness. When the h-BN content in the C/C-BN composite is 10 vol%, the ILSS of the C/C-BN composites was 15.6% higher than that of the C/C composites. However, when the h-BN content is excessive (15 vol%), the densely grafted h-BN will bridge each other, reducing the subsequent CVI densification efficiency to form a loose interface, causing a decrease in the shear strength.

In the duplex steelmaking process, the oxygen flow rate is suppressed to reduce the increasing rate of the temperature in the molten bath, resulting in severe dynamic conditions. To improve the mixing effect of the molten bath, a Laval nozzle structure designed for combination gas has been proposed. In this research, five types of Laval nozzle structure have been built based on the combination gas content, and both numerical simulations and experiments are performed to analyze the flow field of the supersonic jet. The axial velocity and oxygen concentration were measured in the experiment, which agreed well with the numerically simulated data. The results show that both initial axial velocity and potential core length increase with the flow rate of combination gas. Further, applying a higher N2 flow rate could improve the oxygen utilization rate at different ambient temperatures, but this issue increases the oxygen utilization rate, however, the latter can be reduced at higher ambient temperatures.

GPNCA is a long non-coding RNA with unknown functions. In this study, using data from 9 cancers obtained from The Cancer Genome Atlas (TCGA), GPNCA was identified as overexpressed in cancer vs. normal tissues. The upregulation of GPNCA was associated with poor overall prognosis in colon, liver, renal clear cell and breast cancers. The upregulation of GPNCA was partly due to enhanced H3K27ac occupancy on its promoter region via EP300 and KAT2A/GCN5. The overexpression of GPNCA was positively related to tumor metastasis in colon cancer and poor disease-free and recurrence-free survival in colon and liver cancer. Both gene ontology (GO) enrichment and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis indicated that GPNCA was closely linked to regulation of gene transcription and post-transcriptional modifications, which was further supported by in vitro cell cytoplasmic and nuclear RNA purification assessments. Furthermore, GPNCA was associated with cell growth. Our in vitro experiments demonstrated that GPNCA silencing inhibited tumor growth via inhibiting its nearby gene GSK3B. Taken together, these findings highlight GPNCA as a biomarker for cancer diagnosis and a potential target for future cancer drug development.

The Laval nozzle is used widely in steelmaking processes to increase the velocity of an oxygen jet up to approximately 2 Mach numbers. The present research is aimed at determining the effect of the Laval nozzle structure on a supersonic oxygen jet flow field. Both one-dimensional isoentropic flow theory and a characteristic-line method were used to design five-hole oxygen lances of two types and, applicable to oxygen multijets, to analyze their flow field characteristics by a series of numerical simulations and experimental studies. When compared to the conventional oxygen lance designed according to the one-dimensional isoentropic flow theory, the new oxygen lance designed with employment of the characteristic-line method is more effective in both suppressing the shock wave generation and improving the initial axial velocity of oxygen jets under the same test conditions. As a result, a larger impaction cavity was generated by the new oxygen lance and the mass transfer within oxygen, liquid slag, and molten steel was enhanced.

The System #2 flow loop used in this study is a 4−inch−diameter, high−temperature, high−pressure system. In situ corrosion and electrochemical measurements were performed using a homemade flat corrosion specimen and a three−electrode probe. The experiment results show that temperature has an accelerated influence on the corrosion of antibacterial alloy steel. With the increase of temperature and the presence of O2 in the environment, a loose and porous corrosion product film was formed on the surface of the resistant steel, which made it easier for the corrosion medium to enter the corrosion product film from the pore, thus accelerating the corrosion.

This paper reports on the re-engineering of standard five-strand tundish designs into a five-strand asymmetric tundish, which resulted in a non-uniform rate and bias for each strand. We sought to improve the casting conditions by optimizing the liquid steel flow-field in the tundish. Both a water modelling experiment and a numerical simulation were performed to analyze the flow-field according to various diversion hole diameters and injection angles. The results showed that the average residence time decreased as the diameter of the diversion holes increased. As the injection angle was increased, the average residence time initially decreased and then increased. The liquid steel from the ladle shroud rapidly extended to the #2 and #3 strands in the original tundish, which reduced the likelihood of inclusion collision and coalescence.

Ziqing Wang,1,2 Weijie Liao,2,3 Fuhai Liu,2,4 Tingpeng Yang,2 Weidong Xie,2,3 Meijian Liao,3,4 Dayong Gu,5 Yaou Zhang2,3 1School of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China; 2State Key Laboratory of Chemical Oncogenomics, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, People’s Republic of China; 3Key Laboratory in Healthy Science and Technology, Division of Life Science, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, People’s Republic of China; 4Department of Pathology, Xuzhou Medical University, Xuzhou 221104, People’s Republic of China; 5Department of Laboratory Medicine, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen 518035, People’s Republic of ChinaCorrespondence: Yaou ZhangState Key Laboratory of Chemical Oncogenomics, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, People’s Republic of ChinaTel +86-755-2603-6884Email zhangyo@sz.tsinghua.edu.cnDayong GuDepartment of Laboratory Medicine, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen 518035, People’s Republic of ChinaTel +86-13602601597Email wanhood@163.comPurpose: Long non-coding RNAs (lncRNAs) have been shown to be involved in many human diseases. In this study, we aimed to reveal the role and molecular mechanism of lncRNA EPB41L4A-AS1 in type 2 diabetic mellitus (T2DM)-related inflammation.Methods: To explore the relationships between the expression of EPB41L4A-AS1 and inflammatory factors in the blood of T2DM patients, we analyzed peripheral blood mononuclear cell (PBMC) expression microarrays of T2DM patients and expression microarrays of PBMC treated with lipopolysaccharide (LPS) from the GEO database. The relationship between EPB41L4A-AS1 and phospho-p65 was explored by Western blotting (WB) and immunofluorescence. The interactions between EPB41L4A-AS1 and myeloid differentiation factor 88 (MYD88) were also verified through quantitative real-time PCR, WB, and chromatin immunoprecipitation. Glycolysis and mitochondrial stress were detected by Seahorse.Results: EPB41L4A-AS1 showed very low expression, which was significantly negatively correlated with levels of inflammatory factors in PBMCs of T2DM patients and PBMCs treated with LPS. These results were verified by cell experiments on PBMC and THP-1 cells. Knockdown of EPB41L4A-AS1 led to the phosphorylation and nuclear translocation of p65 and thus activated the NF-κB signaling pathway; it also reduced the enrichment of H3K9me3 in the MYD88 promoter and increased expression of MYD88. Overall, EPB41L4A-AS1 knockdown promoted the level of glycolysis and ultimately enhanced the inflammatory response.Conclusion: EPB41L4A-AS1 knockdown activated the NF-κB signaling pathway through a MYD88-dependent regulatory mechanism, promoted glycolysis, and ultimately enhanced the inflammatory response. These results demonstrate that EPB41L4A-AS1 is closely associated with inflammation in T2DM, and that low expression of EPB41L4A-AS1 may be used as an indicator of chronic inflammation and possible diabetic vascular complications in T2DM patients.Keywords: inflammation, diabetes, EPB41L4A-AS1, NF-κB, MYD88

Objective: Sex hormones have been linked to fractures in older women. The purpose of this present study was to investigate the prognostic impact of preoperative sex hormone levels on 30-day mortality in older women undergoing hip fracture surgery.Patients and Methods: A total of 157 female subjects with hip fractures were eligible for the study conducted from January 2010 to December 2019. The serum levels of sex hormones [follicle-stimulating hormone, prolactin, progesterone, testosterone, luteinizing hormone, and 17-β-estradiol (E2)] were measured at admission. To evaluate the prognostic significance of sex hormone levels, Cox proportional hazard models and Kaplan–Meier analyses were applied.Results: Of the 157 subjects, 13 (8.28%) deceased within 30 days. The deceased subjects had lower progesterone (P = 0.021) and E2 (P < 0.001) levels than the surviving group. Higher progesterone (HR = 0.168, 95% CI = 0.037–0.673) and E2 (HR = 0.857, 95% CI = 0.690–0.968) levels were the key protective factors for 30-day mortality in older women undergoing hip fracture surgery. Survival analysis showed that subjects with lower E2 or/and progesterone levels had a significantly higher percentage of 30-day mortality (log-rank test, P < 0.05).Conclusion: E2 and progesterone might be effective predictors of 30-day mortality in older women undergoing hip fracture surgery.

The phonocardiogram (PCG) is an important analysis method for the diagnosis of cardiovascular disease, which is usually performed by experienced medical experts. Due to the high ratio of patients to doctors, there is a pressing need for a real-time automated phonocardiogram classification system for the diagnosis of cardiovascular disease. This paper proposes a deep neural-network structure based on a one-dimensional convolutional neural network (1D-CNN) and a long short-term memory network (LSTM), which can directly classify unsegmented PCG to identify abnormal signal. The PCG data were filtered and put into the model for analysis. A total of 3099 pieces of heart-sound recordings were used, while another 100 patients’ heart-sound data collected by our group and diagnosed by doctors were used to test and verify the model. Results show that the CNN-LSTM model provided a good overall balanced accuracy of 0.86 ± 0.01 with a sensitivity of 0.87 ± 0.02, and specificity of 0.89 ± 0.02. The F1-score was 0.91 ± 0.01, and the receiver-operating characteristic (ROC) plot produced an area under the curve (AUC) value of 0.92 ± 0.01. The sensitivity, specificity and accuracy of the 100 patients’ data were 0.83 ± 0.02, 0.80 ± 0.02 and 0.85 ± 0.03, respectively. The proposed model does not require feature engineering and heart-sound segmentation, which possesses reliable performance in classification of abnormal PCG; and is fast and suitable for real-time diagnosis application.

The top-blowing supersonic oxygen jet is now used widely in steelmaking and metal refining processes. However, the ambient temperature and oxygen flow rate is changed during top-blowing pro...

The coherent jet technology was widely used to improve the stirring effect of molten bath in steelmaking field, and the key to this technology was to form a low-density zone around the main oxygen ...

Coherent jet technology was been widely used in the electric arc furnace steelmaking process to protect the kinetic energy of supersonic oxygen jets and achieve a better mixing effect. For this technology, the total temperature distribution of the shrouding jet has a great impact on the velocity of the main oxygen jet. In this article, a supersonic shrouding nozzle using a preheating shrouding jet is proposed to increase the shrouding jet velocity. Both numerical simulation and experimental studies were carried out to analyze its effect on the axial velocity, total temperature and turbulence kinetic energy profiles of the main oxygen jet. Based on these results, it was found that a significant amount of kinetic energy was removed from the main oxygen jet when it passed though the shock wave using a high-temperature shrouding jet, which made the average axial velocity of the coherent jet lower than for a conventional jet in the potential core region. However, the supersonic shrouding nozzle and preheating technology employed for this nozzle design significantly improved the shrouding gas velocity, forming a low-density gas zone at the exit of the main oxygen jet and prolonging the velocity potential core length.

Coherent jet technology has been widely used in EAF steelmaking process because of the longer potential core length and stronger impacting power of the supersonic oxygen jet. However, more oxygen and fuel gas are consumed to achieve excellent characteristics of coherent jets, which causes the increase in steelmaking cost. Computational fluid dynamics simulation and experimental measurement of the coherent jets with CH4 + N2 mixed fuel gas were carried out aiming at reducing the consumption of fuel gas. The numerical simulation results showed good agreement with the experimental data. As a result, high proportion of N2 negatively affects the combustion of CH4, which is not good for the protection of oxygen jets. While the gas composition is 75% CH4 + 25% N2, the N2 addition to the CH4 leads to an expanding of CH4 combustion zone, and the energy generated by the combustion reaction could be delivered to the molten bath more efficiently, which is one control scheme with high performance–price ratio.

The self-powered wireless sensor systems are highly sought for the information era, as they are able to link everything together, yet without the need for electric power supply. They have been exploited for applications in various fields, particularly for environment-related ones. Here, we propose a fully self-powered triboelectric nanogenerator (TENG)-based wireless traffic monitoring system for real-time monitoring of illegally entered electric motorbikes on the footpaths, and flow rates of pedestrians and motorbikes, and speed and driving direction of electric motorbikes on non-motorized lanes. The TENG was used to directly convert the energy from pedestrian’s stepping and electric motorbike’s rolling into an oscillating signal with encoded sensing information, and transmit it to the receiver wirelessly via magnetic resonance coupling. Results showed that the multi-variable traffic monitoring system can identify pedestrians and motorbikes, check the illegally entered motorbikes on the footpath, and measure speed of the motorbikes with an accuracy of over 94%, monitor driving direction of electric motorbikes on non-motorized lanes. The self-powered wireless traffic monitoring system is simple in structure, low cost, easy to install, and spontaneous response to the traffic condition, and does not contain electronic devices, microcontrollers and transmission chips but the passive components, hence it has great application potential as a green intelligent traffic monitoring system.

Intelligent traffic light control system belongs to the field of transportation public safety control. So far, the traffic light control system on the market cannot change the working time of the traffic lights according to the actual traffic flow, which is not conducive to the easing of the traffic flow and easy to cause traffic jams. Therefore, it is necessary to solve the problem of the existing traffic light control system which cannot adjust the working hours of the traffic light according to the actual road conditions, so as to alleviate the traffic jam at the intersection to a certain extent. In this paper, the design of intelligent traffic light control system uses AT89C51 MCU as the core device. The system controls the traffic of different times and different conditions, and it can alleviate traffic jam to a certain extent. This paper analyzes the hardware and software designes of intelligent traffic light control system, and simulates traffic light control by simulation software. The system of this paper is simple in structure, economical and practical, reliable in operation and it can effectively dredge the traffic.

During the electric arc furnace steelmaking process, the coherent jet technology was widely used to protect the kinetic energy of the supersonic oxygen jet and achieve better mixing effects. Comparing with the conventional oxygen lance, the coherent lance could increase the surface area of impaction cavity, resulting in a better stirring effect and higher reaction rate. However, there was limited research about the effect of restriction structure for the coherent lance tip on the flow field characteristic of the main oxygen jet. In this research, three kinds of restriction structures have been investigated by numerical simulation and combustion experiment at room and high ambient temperature conditions. Then an optimum restriction structure would be tested in a 75 t electrical arc furnace steelmaking process to verify its metallurgical property.

In this study, 2.5D carbon fiber reinforced pyrocarbon matrix composites with a BN interphase (Cf/BN/PyC) were prepared by chemical vapor infiltration. Through comparing the distribution of thermal residual stress and the evolution of the interface microstructure of composite before and after heat treatment, the reason why the structure and orientation of the BN interphase in the Cf/BN/PyC composite deviate from the layered structure required for the expected compliant interface was analyzed. The results show that the crystalline skin of Cf affects the order of BN near the Cf/BN interface, thereby forming BN interphase with a structural gradient from the beginning. The infiltration process of pyrocarbon interacts with the growth and rearrangement process of BN, resulting in incomplete crystallization of BN. After heat treatment at 1600°C, BN interphase with high crystallinity in the nano-domain but disordered orientation is formed, although it can also debond the interface according to He and Hutchinson's model. The BN grain orientation deviates from the fiber axis mainly due to multi-factor coupling, in which the axial residual thermal stress generated at the Cf/BN/PyC interface is the main influencing factor. Understanding the influence of the heat treatment (HT) on the atomic-domain orientation change and structural evolution during the preparation of boron nitride (BN) interphase by chemical vapor infiltration paves us an effective way to modify the preparation of interphase with low fracture energy.

The stirring ability and flow field characteristic of conventional and nozzle twisted oxygen lance (Twisted angles are 4°, 8° and 12°, respectively) on the molten bath were analysed. The mixing time, impacting depth and impacting radius are measured. Flow field characteristics of multi-phase flow are calculated by numerical simulation. Compared with conventional oxygen lance at industrial application research, it shows that the 8° oxygen lance could stir molten better in steelmaking process for the 120t dephosphorisation converter. These findings agree well with the experimental results of the water experiments and the numerical simulations. Finally, an optimal twisted angle is determined.

An increasing number of high Concrete-Faced Rockfill Dams (CFRDs) have been and are being built in highly seismic hazardous regions. Because there are few examples, the failure mechanisms for each damaged CFRD still remain unclear, which prevents a rational evaluation of aseismic performance of a CFRD. In this paper, a series of large-scale shaking table tests are conducted to determine the dynamic failure modes of CFRDs, especially the failure mechanism of the face slab. A type of model slab material is developed according to similitude rules. Particle Image Velocimetry (PIV) is used and improved to track the motion of each grain and subsequently measure the entire velocity field of the deforming cross-sections of dam models. The failure processes of the dams, the failure mechanisms of the slab fractures and the slab dislocations are discussed based on the experimental results. The experiments indicate that large deformations of the uppermost part of the dam caused the face slab to curve upward and crack. Another important fracture morphology of the face slab is the dislocation of its joint. The change in the granular fabric caused the granular slope to slide down and thrust outward, eventually dragging the upper half of the face slab down against its lower half; this motion is accompanied by the formation of a joint dislocation. Therefore, the stability and anti-deformation ability of both the downstream slope and the crest region of the upstream slope should be improved to withstand earthquake. The results of the shaking table model tests are consistent with the numerical simulation, and both results support the prototype dam׳s seismically induced failure characteristics.

A finite element method model has been elaborated to study the localized corrosion around a MnS inclusion particle in stainless steel, taking into account the three electrochemically active phases of the matrix, passive film and MnS inclusion. The simulation results show the evolution of this micro-galvanic corrosion process, which is initiated by MnS dissolution, followed by the simultaneous dissolution of the inclusion and matrix, and finally, the MnS inclusion stops dissolving and turns to be cathodic, leaving the matrix as the only corroding phase (“trenching” process). The deposition kinetics of the corrosion products and pH distribution around the corroding area are also predicted.

When m value is above 21, If the horizontal load has not reached the design value of the theoretical ultimate bearing capacity, the foundation pile will first appear bending failure. That is to say, when m value is greater than 21, the horizontal bearing capacity of pile group bearing platform foundation begins to depend on the bending strength of pile itself. The ultimate horizontal bearing capacity of pile group bearing platform foundation in actual engineering has been difficult to reach the ideal design value。 When the value of M is less than 21, the actual horizontal ultimate bearing capacity is consistent with the theoretical calculation, when the m value is greater than 21, the actual horizontal ultimate bearing capacity can be calculated according to the simplified formula proposed in this paper.

2.5D carbon fiber (Cf)-reinforced carbon and boron nitride dual matrix composites (C/C-BN) were prepared by a combined process of C/C silanization, hexagonal boron nitride (h-BN) slurry impregnation, and chemical vapor infiltration (CVI). The surface morphology of Cf after each step of modification, the fracture surface and microstructure of the C/C-BN composites were systematically characterized by scanning electron microscopy. Through the hydrolysis of silane, a polysiloxane network was successfully formed inside the porous C/C composites, which provided more attachment sites for the subsequent grafting of h-BN filler and the deposition of pyrocarbon (PyC). The microstructure and mechanical properties of the C/C-BN composites containing three different of h-BN fillers content were studied in comparison with pure C/C composites. The TEM characterization of the h-BN filler/PyC interface confirmed that the different crystal planes of the h-BN grains affect the structure of the PyC deposited thereon. The results show that the uniformly distributed h-BN filler reduces the size, thermal shrinkage anisotropy, and texture of the PyC deposited around it, resulting in the disappearance of the interlayer cracks in the matrix and the enhancement of the cohesion of the composite. The tight physical bond at the interface is due to the radial compressive stress caused by the thermal mismatch between the fiber, matrix, and h-BN fillers. Therefore, as the h-BN fillers content increases, the flexural strengths, compressive strength of the C/C-BN composites increase, which are both greater than that of C/C composite, and the compression properties gradually tended to be isotropic. However, when the h-BN content in the C/C composite is excessive (such as the volume content of 15 vol%), the densification efficiency of the subsequent CVI is reduced. As a result, the compactness of the transition interface and mixed matrix composed of h-BN and PyC decreased, which led to the decrease of mechanical properties of the composites.

Automated cell classification is an important yet a challenging computer vision task with significant benefits to biomedicine. In recent years, there have been several studies attempted to build an artificial intelligence-based cell classifier using label-free cellular images obtained from an optical microscope. Although these studies showed promising results, such classifiers were not able to reflect the biological diversity of different types of cell. While in terms of malignant cell, it is well-known that intracellular actin filaments are altered substantially. This is thought to be closely related to the abnormal growth features of tumor cells, their ability to invade surrounding tissues and also to metastasize. Therefore, being able to classify different types of cell based on their biological behaviors using automated technique is more advantageous. This article reveals the difference in the actin cytoskeleton structures between breast normal and cancer cells, which may provide new information regarding malignant changes and be used as additional diagnostic marker. Since the features cannot be well detected by human eyes, we proposed the application of convolutional neural network (CNN) in cell classification based on actin-labeled fluorescence microscopy images. The CNN was evaluated on a large number of actin-labeled fluorescence microscopy images of one human normal breast epithelial cell line and two types of human breast cancer cell line with different levels of aggressiveness. The study revealed that the CNN performed better in the cell classification task compared to a human expert.

Background LncRNAs have been found to be involved in various aspects of biological processes. In this study, we aimed to uncover the molecular mechanisms of lncRNA EPB41L4A-AS1 in regulating glycolysis and glutaminolysis in cancer cells. Methods The expression of EPB41L4A-AS1 in cancer patients was analyzed in TCGA and GEO datasets. The level of cellular metabolism was determined by extracellular flux analyzer. The relationship between p53 and EPB41L4A-AS1 was explored by qRT-PCR, luciferase assay and ChIP assay. The interactions between EPB41L4A-AS1 and HDAC2 or NPM1 were determined by RNA immunoprecipitation, RNA pull-down assay and RNA-FISH- immunofluorescence. Findings EPB41L4A-AS1 was a p53-regulated gene. Low expression and deletion of lncRNA EPB41L4A-AS1 were found in a variety of human cancers and associated with poor prognosis of cancer patients. Knock down EPB41L4A-AS1 expression triggered Warburg effect, demonstrated as increased aerobic glycolysis and glutaminolysis. EPB41L4A-AS1 interacted and colocalized with HDAC2 and NPM1 in nucleolus. Silencing EPB41L4A-AS1 reduced the interaction between HDAC2 and NPM1, released HDAC2 from nucleolus and increased its distribution in nucleoplasm, enhanced HDAC2 occupation on VHL and VDAC1 promoter regions, and finally accelerated glycolysis and glutaminolysis. Depletion of EPB41L4A-AS1 increased the sensitivity of tumor to glutaminase inhibitor in tumor therapy. Interpretation EPB41L4A-AS1 functions as a repressor of the Warburg effect and plays important roles in metabolic reprogramming of cancer.

Background To compare the efficacy and safety of K-wire tension band fixation (KTB) with other alternative approaches (cannulated screws, cable pin, and ring pin) for treatment of patella fractures by performing a meta-analysis. Methods PubMed and EMBASE databases were searched for all relevant studies. Standardized mean difference (SMD) or relative risk (RR) and their corresponding 95% confidence intervals (CIs) were calculated for continuous or dichotomous outcomes via either a fixed- or random-effect model using Stata 13.0 software. Results Nine literatures involving 949 patients (581 in the KTB group and 368 in the control group) were included. Pooled analysis showed there were no differences in the success rate, operative time, healing time, and number of infections between patients undergoing KTB and others. However, the incidence of complications (RR = 8.04, 95% CI = 4.45–14.53; p

The coherent jets are now used widely in electric arc furnace steelmaking process to increase the stirring ability, reaction rates, and energy efficiency. However, there has been limited research on the basic physics of the coherent jets. In the present study, the characteristics of flow field of supersonic coherent jet in hot and cold condition were studied. The total temperature and axial velocity were measured by combustion experiment. Flow field characteristics of supersonic coherent jet were simulated by Fluent software. The detailed chemical kinetic mechanism is presently used for the modeling of reactions. It consists of 53 species, plus Ar and N2, for a total of 325 reversible reactions. The present study showed that the shrouding flame decreases the entrainment of the ambient gas to the central supersonic jet, which results in a low expansion rate for the coherent supersonic jet. The higher ambient temperature can prolong the potential core of coherent jet and conventional jet. However, the potential core of coherent jet reduces with oxygen temperature increasing, which is opposite to conventional jet.