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In order to clarify the dephosphorization mechanism of DRI (Direct Reduced Iron) derived from hydrogen reduced high-phosphorus iron ore during the electric arc furnace melting process, slag was prepared using reagent-grade powder based on the gangue mineral composition of high-phosphorus oolitic hematite. By incorporating varying amounts of CaO, FeOx, and reduced iron powder, experiments simulating the dephosphorization of melting separation slag from DRI with different basicity and metallization rates were conducted at 1873 K. The results show that phosphorus in the iron primarily exists in the form of Fe–P–O spherical slag inclusions and FexP, while in the slag, phosphorus mainly resides within the silicate phases. As the amount of CaO added increases, there is a significant decrease in the phosphorus content within the slag inclusions, and the P-containing compounds in the iron gradually shift from FexP and Fe3(PO4)2 to FeO. As the dephosphorization capacity of the slag increases, the distribution of phosphorus-rich phases in the rapidly cooled slag becomes more extensive. When the basicity increases to 3, the phosphorus-rich phases in the slag transition to 2CaO·SiO2 and 3CaO·SiO2. When the basicity is fixed at 2.5, regulating the metallization rate can control the FeOx content in the molten slag, thereby enhancing the dephosphorization ability of slag. The results show that under conditions of a DRI basicity of 2.5 and a metallization rate of 85%, slag/metal separation can produce low-phosphorus iron with 0.022 wt% P, achieving a dephosphorization rate exceeding 95%.

A top-fired heating furnace is a type of heating equipment for the heat carrier used in the dry retorting process of oil shale. This study explores the energy consumption and pollutant emissions of such furnaces, focusing on the influence of the excess air coefficient and air staging ratio on the NO emission characteristics of the combustion chamber outlet, using the numerical simulation method. The research shows that with the increase of the excess air coefficient α, the combustion chamber temperature and the NO emission value of the combustion chamber outlet first increase and then decrease, reaching a peak at α = 1.05. The combustion chamber temperature directly affects the NO emission value, showing the change law of thermodynamic NO with temperature. When the air is staged, the factors affecting the NO emission value are more complicated, and the amount of NO generation is not only affected by the uniformity of combustion temperature but also by the mixing characteristics. When the proportion of secondary air is 30%, the mixing fraction distribution is the most uniform, the mixing effect of fuel gas and air is the best, and the NO emission value at the combustion chamber outlet is the lowest.

The purpose of this study is to introduce an air nozzle on top of a top-fired heating furnace designed for oil shale retorting, using numerical simulations to delineate enhanced gas flow, heat transfer, and combustion in the furnace. Traditional heating flow fields, temperatures, and nitric oxide (NO) emission behaviors were carefully studied alongside furnaces fitted with various top jet systems. Our findings conclude that the introduction of top air supply leads to the development of a stable vortex pair in the combustion chamber, enhancing flame stability. Moreover, the incorporation of the top jet structure noticeably enhances the combustion chamberâs temperature and homogeneity, retaining the benefits of swirl combustion, optimizing high-speed entrainment effects, promoting gas flow stratification, and substantially reducing NO production. With the implementation of the top air supply, NO emission is reduced to below 50 mg/Nm3, while peak incomplete combustion heat loss decreases to less than 1%, which successfully helps achieve the goal of improving thermal efficiency, saving energy, and reducing emissions from the heating furnace.

Objective To explore the mechanism of Wnt5a on keratinocyte involved in the peripheral sensitization of complex regional pain syndrome type-Ⅰ (CRPS-Ⅰ) by regulating the expression of MMP9, and search for potential therapeutic strategies. Methods Cultured HaCaT cells were treated with oxygen glucose deprivation/re-oxygenation (OGD/R). The early stage of mitochondrial damage and membrane potential changes after OGD/R and the effects of Box5 (Wnt5a inhibitor) at different concentrations (20 μmol/L, 40 μmol/L) on MMP9 were explored. Adult male Sprague-Dawley rats were divided into Control group(n=8), CPIP group (n=8), Box5 (20) group (n=8) and Box5 (40) group (n=8). The rat chronic post-ischemia pain (CPIP) model was established to mimic the pathophysiological process of CRPS-Ⅰ. Box5 (20) group and Box5 (40) group were treated with intraplantar injection of 20 μmol/L and 40 μmol/L Box5 100 μL, respectively. The changes of mechanical withdrawal threshold and thermal withdrawal latency were measured within two weeks, and the skin inflammatory infiltration and keratosis were observed by HE staining. The expression of MMP9 was observed by immunofluorescence, and the levels of IL-1β and TNF-α in dorsal root ganglion of different groups were detected by ELISA. Results Vitro experiment: After OGD/R treatment, the mitochondrial atrophy was observed in OGD/R group under transmission electron microscope and the average fluorescence intensity of MMP9 was found to increase significantly (P

Objective To elucidate whether coffee consumption and caffeine intake was associated with various subtypes of pain based on extensive data from publicly accessible databases. Methods The information was extracted from three cycles of the American National Health and Nutrition Examination Survey (1999—2000, 2001—2002, 2003—2004), encompassing data on coffee consumption, pain information, and 11 covariates (including age, gender, race, etc.). Multinomial logistic regression in three models were utilized for analysis. Results A total of 13 428 participants were included in this study, with a mean age of (49.79±19.06)years and a male-to-female ratio of 0.9∶1. Daily coffee intake: non-drinker 7794(58.0%), > 0-2 cups 2077(15.5%), > 2 cups 3557(26.5%); daily caffeine intake: without intake 7794(58.0%), > 0-200 mg 3152(23.5%), > 200 mg 2482(18.5%); pain situation: no pain or pain duration < 24 h 10 202(76.0%), acute pain 910(6.8%), subacute pain 369(2.7%), chronic pain 1947(14.5%). After weighting, 13 428 participants were expected to represent 190 million(190 709 157) U.S. citizens aged ≥20 years, and the overall prevalence of acute, subacute, and chronic pain in the U.S. population during that period was estimated to be 8%, 3%, and 16%, respectively. Without adjusting for covariates, individuals who consumed more than 2 cups of coffee or 200 mg of caffeine per day exhibited an elevated risk of chronic pain compared to non-coffee/caffeine drinkers, with an odds ratio of 1.354(95% CI: 1.187-1.544) and 1.372(95% CI: 1.185-1.587), respectively. After adjusting for partial covariates including age, sex, and race, individuals who consumed more than 2 cups of coffee or more than 200 mg of caffeine per day still demonstrated an increased risk of chronic pain with an odds ratio of 1.243(95% CI: 1.083-1.427) and 1.249 (95% CI: 1.072-1.456), respectively. However, after all covariates were adjusted, there was no significant association between coffee/caffeine consumption and chronic pain. Furthermore, the number of cups of coffee consumed or caffeine intake showed no significant correlation with acute and subacute pain. Conclusions Compared with nondrinkers, heavy daily coffee drinkers may be more likely to have chronic pain, but it is affected by multiple factors. Basic research and prospective clinical studies are needed to further determine the causality in this association.

Abstract Purpose To characterize the phenotype and genotype of a Chinese family with autosomal‐dominant retinitis pigmentosa (RP) accompanied by iris coloboma. Methods The proband, a 34‐year‐old male, was examined with his family by using fundus photography, optical coherence tomography (OCT), autofluorescence, and full‐field electroretinography (ffERG). Genetic analyses were conducted through whole‐exome sequencing (WES) to screen for variations. Results Three members of this Chinese family were shown to be bilateral iris coloboma. The male proband and his mother exhibited typical RP feature. The proband's late grandfather had been documented manifestation of iris coloboma. The mode of inheritance was confirmed to be autosomal dominance. Through linkage analysis and WES, a heterozygous variation in the miR‐204 gene (n.37C>T), a noncoding RNA gene, was identified in these three members. Conclusions In this third independent and the first Asian family, the existence of a miR‐204 variant associated with RP accompanied by iris coloboma was confirmed. Our findings reinforce the significance of miR‐204 as an important factor influencing visual function in the retina. When phenotypes like RP accompanied by iris coloboma in an autosomal‐dominant pattern, including in Chinese patients, miR‐204 aberrations should be considered.

Spectrometer miniaturization is desired for handheld and portable applications, yet nearly no miniaturized spectrometer is reported operating within terahertz (THz) waveband. Computational strategy, which can acquire incident spectral information through encoding and decoding it using optical devices and reconstruction algorithms, respectively, is widely employed in spectrometer miniaturization as artificial intelligence emerges. We demonstrate a computational miniaturized THz spectrometer, where a plasmonic filter array tailors the spectral response of a blocked-impurity-band detector. Besides, an adaptive deep-learning algorithm is proposed for spectral reconstructions with curbing the negative impact from the optical property of the filter array. Our spectrometer achieves modest spectral resolution (2.3 cm−1) compared with visible and infrared miniaturized spectrometers, outstanding sensitivity (e.g., signal-to-noise ratio, 6.4E6: 1) superior to common benchtop THz spectrometers. The combination of THz optical devices and reconstruction algorithms provides a route toward THz spectrometer miniaturization, and further extends the applicable sphere of the THz spectroscopy technique.

Antimicrobial peptides have antibacterial effects on various pathogenic microorganisms, including natural antimicrobial peptides and synthetic antimicrobial peptides. According to the structure of natural antimicrobial peptides, synthetic antimicrobial peptides can be obtained by recombining different functional domains, adjusting the original amino acid sequence, or completely redesigning the peptides from scratch. Antimicrobial peptides can inhibit the growth of various cariogenic microorganisms and the formation of microbial biofilms. They also reduce acid production and acid resistance of microorganisms. Natural antimicrobial peptide genes can be used as genetic susceptibility markers for predicting the development of caries, thus, showing potential applications in the prevention and treatment of dental caries. The instability of natural antimicrobial peptides and the inability to achieve targeted sustained release limit their application in the prevention and treatment of oral caries. Synthetic antimicrobial peptides can enhance their stability and the antibacterial effect. Synthetic antimicrobial peptides can also be polymerized with common oral adhesives to reduce the incidence of microleakage after filling treatment for caries and to prevent the occurrence of secondary caries. The pH-sensitive antimicrobial peptides are slowly released to promote remineralization in the process of caries. However, the safety and biocompatibility of synthetic antimicrobial peptides are worse than those of natural antimicrobial peptides. Moreover, the combined effect of antibacterial peptides and anticaries drugs, such as fluoride, is still uncertain. Therefore, in this paper, we will review the design methods, application and underlying mechanisms of antimicrobial peptides to introduce novel methods and ideas for the prevention and treatment of dental caries.

The development of the oxy-fuel porous media combustion technique not only takes advantage of the characteristics of porous media combustion, such as a relatively low lean-burn limit and small volume, but also dramatically facilitates carbon capture and storage. In this paper, a two-layer porous burner model is established, in which a two-temperature equation model is adopted for calculation purposes. Differences in combustion behaviour between oxy-fuel and air-fuel conditions are compared. The results show that the difference in physical properties between CO2 and air is the main reason for the significant variation of combustion behaviours under the conditions of oxy-fuel compared to air-fuel. The specific performance is lower combustion temperature and flame propagation speed. The temperature under oxy-fuel combustion conditions is 300 K lower than that under air-fuel combustion conditions at an equivalence ratio of 0.6, and the stable range of oxy-fuel combustion is only approximately 50% of air-fuel combustion. The impact of porous media material parameters on combustion behavior has been investigated. These variables include the equivalence ratio, material thermal conductivity, volume heat transfer coefficient, and extinction coefficient, while the ratio of O2/CO2 remains fixed at 0.21/0.79. The influence of these variables on the stable velocity range and temperature field is consistent, but a large difference in values occurs. Reducing the thermal resistance of the burner by adjusting the properties of the porous matrix can increase the velocity limit of stable combustion. However, even if the thermal conductivity and extinction coefficient are increased by 5 times, there will be no significant impact on the stable range. Reducing the pore size of the combustion zone by 50% will increase the stable range by over 100%.

TurboID, a proximity labelling method based on mutant biotin ligase, is an efficient new technique for recognizing protein-protein interactions and has been successfully applied to living cells. Sialic acid is typically the terminal monosaccharide attached to many glycoproteins and plays many important roles in many biological processes. However, the lack of enrichment methods for terminal sialic acid glycosylation in vivo hinders the identification and analysis of this glycosylation. Here, we introduce TurboID to identify terminal sialic acid glycosylation in living cells. SpCBM, the carbohydrate-binding domain of sialidase from Streptococcus pneumoniae, is fused with TurboID and overexpressed in HeLa cells. After streptavidin-based purification and detection by mass spectrometry, 31 terminal sialic acid N-glycosylated sites and 1359 putative terminal sialic acid glycosylated proteins are identified, many of which are located in the cytoplasm and nucleus.

The nano-SiC/AlSi7Mg mixed powder was prepared by mechanical mixing method. The specimens of nano-SiC particle reinforced AlSi7Mg composite were fabricated by selective laser melting (SLM). The relative density, phase and microstructure were observed and analyzed, and the microhardness and tensile properties were tested. The results show that the relative densities of SLM nano-SiC/AlSi7Mg composite are increased firstly and then decreased with the increase of scanning speed and scanning space, and the maximum relative density reaches 99.75%. The microstructure of specimens is similar to that of SLM-formed Al-Si alloys, and the network-structured Si phase is uniformly embedded in the α-Al matrix. There are nano-SiC agglomerates and Mg2Si phase in the α-Al matrix, which has a similar distribution to Si. Compared with AlSi7Mg, the microstructure of specimens is changed from columnar to equiaxed grain, and the grains are significantly refined (the average grain size is 1.36 μm). Due to the addition of SiC, grain refinement strengthening and solid solution strengthening are produced, and the hardness and strength of composite are significantly improved. The hardness, tensile strength and yield strength reach 137.3HV, 448.3 MPa and 334.7 MPa, respectively. However, the elongation is reduced to 3.9%, and the fracture mode is mainly brittle fracture.

In order to study the melting and falling off of the iced conductor under DC ice melting process by considering a lgj-400 / 50 transmission conductor as a research object, Ansys LS-DYNA model is used for simulating the response of materials under short periods of high-intensity loads and a nonlinear structural dynamics model is used to establish the finite element model of split conductor system in the actual process. In the process of finite element analysis, solid45 element is used to model the conductor layer by layer. During the calculation process, the life and death element method is used to transform its element stiffness matrix to near zero icing element for accurately simulating the actual situation during ice melting. Currently, the research on the deicing of the split conductor mostly equates the split conductor to a single conductor for calculation. In the actual ice melting operation, the split conductor system has a phenomenon of asynchronous deicing, so it is necessary to analyze the deicing of different sub-conductors. The results show that the jump height of the deicing conductor under DC deicing is smaller than that of the normal deicing. The jump height and tension of conductor deicing decrease with an increase in the deicing current. When the sub-conductors of the four-bundle conductor spacer system are not deiced synchronously, the two sub-conductors on the diagonal and two sub-conductors below are deiced, the split conductor system is relatively stable. When the sub-conductors under other working conditions are not deiced synchronously, the four-bundle conductor spacer system has lateral swing, resulting in torsional risk, which causes conductor wear and strand breaking accidents.

The single-lap joints with different overlap lengths were bonded by carbon fiber reinforced plastics (CFRP) laminate, and their failure load, fracture process and strain fields were characterized by digital image correlation (DIC) and universal testing machine. The effects of overlap length on the tensile properties, fracture process, strain distribution and failure characteristics of single lap joints were studied. The results show that with the development of overlap length, the average shear strength of joints is decreased firstly and then tends to be stable. The secondary bending effect of joints caused by the eccentric load during the stretching process becomes more significant with the increase of overlap length, the end deformation of the lap area is increased, and the initial failure position of joints changes from one end to both ends of the lap area. The strain concentration area at the end of the front and side of joints transitions from asymmetric to symmetric. The peeling stress of joints gradually is increased, and the main failure mode between layers is changed from shear to peeling failure. The failure mode of joints go through the process from interface and slight fiber tearing to mixed failure and then to delamination.

Water retention curve (WRC) is an important tool to study the hydraulic and mechanical properties of unsaturated soils, such as permeability, strength and deformation properties. Most of the existing WRC models fail to reflect the water retention mechanisms of unsaturated soils or they are complex in form, and these models are hard to give good performance on modelling the bimodal and multimodal WRCs. In this study, based on analyzing the water retention mechanisms of unsaturated soils, the WRC was divided into two domains that are governed by adsorption and capillary mechanisms, respectively. An adsorption water retention curve model (WRCM) was developed based on micro-pore filling theory and Kelvin’s law. A capillary WRCM was established based on the capillary condensation theory and Young-Laplace equation. Then, a new water retention curve model over the full suction range was built by superposing the adsorption and capillary WRCMs. Finally, the new model was validated through modelling the experimentally measured WRCs of six representative unsaturated soils, including Shanghai soft clay, Xi’an loess, Nanyang expansive soil, Guilin lateritic clay, Western Liaoning aeolian soil and Inner Mongolia Gaomiaozi (GMZ) bentonite. Results showed that the proposed model, which was simple in form with definite physical meaning parameters and successfully reflected the adsorption and capillary mechanisms of water retention, was able to simulate WRCs with different shapes for different types of soils under different conditions.

【Background】 The eastern foot of Helan Mountain in Ningxia is thought to be one of the most suitable “golden zones” for wine grape in the world, and a large-scale grape cultivation corridor has been proposed to be built with drip irrigation tipped as the most suitable irrigation method in this region. While the benefits of different drip irrigation methods to grape growth have been studied, most of them focused on comparison with traditional furrow irrigations under different irrigation amounts. In contrast, there is a paucity of studies on how different drip irrigation methods and irrigation amounts combine to affect wine grape growth and the fruit quality. 【Objective】 Considering gravel texture of the soil in this region, this paper is to plug this gap in attempts to find the most suitable irrigation amount and drip irrigation system for industrial-scale production of wine-grape in this region. In particular, we focus on how different drip irrigation methods and irrigation amounts impact growth, yield and quality of the wine grape. 【Method】 The experiment was conducted in a field, and it considered three factors: mulching, drip irrigation method and irrigation amount. Combining the first two factors, there were three irrigation methods: drip irrigation without mulching (A1), drip irrigation above the mulching film (A2) and drip irrigation underneath the mulching film. Added to these three irrigation methods were three irrigation amounts: high (W1), middle (W2) and low (W3). Overall, there were nine treatments which were designed using the randomized block experiment. In each treatment, we measured growth, photosynthesis, yield and fruit quality of the wine grape. 【Result】 Both mulched drip irrigation and increasing irrigation amount can promote growth and development of the wine grape, with the average new shoot length and stem diameter increasing by 4.49% and 6.77%, respectively, compared to drip irrigation without mulch. With irrigation amount increasing, both the 100-fruit weight and yield of the grape increased gradually, with average yield of the drip irrigation underneath and above the film increasing by 48.26% and 20.26% respectively, compared to irrigation without mulch. The sugar acid ratio of the grape irrigated underneath the film was in the range of 35.23~43.32, more reasonable than those under other drip irrigation methods. 【Conclusion】 With annual rainfall of only 126.3 mm, irrigating 2 295 m3/hm2 of water in 5~7 times with the much film covering the drip emitters is optimal for growth, yield and quality of the wine grape grown in the gravel soils in eastern foot of the Helan Mountain.

With the increasing demand for high-quality steel, the requirements for the efficiency and stability of deep desulfurization are increasing too. The Kanbara Reactor (KR) is widely accepted around the world because of its high efficiency and economy. In order to destroy the rigid motion of molten iron in this area, two kinds of blade structures are designed and compared with traditional blades. In this study, a three-dimensional transient coupling mathematical model was established by using volume of fluid (VOF) and discrete phase model (DPM) to simulate the KR desulfurization process. The turbulence intensity of the molten iron, main vortex size and desulfurizing agent (DA) particle distributions for the three impeller models were investigated in detail. Model results showed that the staggered blade structure may improve the desulfurization efficiency of the KR process, and the desulfurization rate increases from 95.7% to 97.1% when compared with ordinary blades. The main reason for this can be attributed to the enhanced turbulence intensity of the molten iron, larger main vortex size and more uniform DA particle distributions. Plant tests also showed that the desulfurizer consumption per 1 ppm sulfur for the staggered blades was reduced by approximately 8.6%.

Acetolactate synthase (ALS)-inhibiting herbicides play an important role in controlling broad-leaved weeds. Populations of Sagittaria trifolia L. showed resistance to ALS-inhibiting sulfonylurea herbicides (e.g. bensulfuron-methyl) in paddy fields in the northeast of China. In our study, whole-plant bioassays were performed on eight suspected resistant S. trifolia populations that showed high levels of resistance to bensulfuron-methyl, with resistance indices from 31.06 to 120.35. The results of ALS-activity assays were consistent with the observed whole-plant dose-response data. This confirmed that resistant populations displayed significantly higher ALS activity than the sensitive population due to prevention of normal enzyme-herbicide interaction. The mutations Pro-197-Ser, Pro-197-His, Pro-197-Thr and Pro-197-Leu were identified in the ALS gene of resistant populations. Pro-197-His and Pro-197-Thr mutations conferring resistance to bensulfuron-methyl are reported for the first time in S. trifolia. All resistant populations were resistant to sulfonylurea (SU) herbicides, but not to imidazolinone (IMI) herbicides. HLJ-5 and JL-3 populations were resistant to bispyribac-sodium of the pyrimidinyl-thiobenozoate (PTB) class of ALS herbicides, JL-2 to penoxsulam of triazolopyrimidine (TP) class and JL-1 to pyribenzoxim, also of PTB class. The eight S. trifolia populations were susceptible to other herbicide modes of action tested.