Search

Bevel gears are widely used in aerospace transmission systems as well as modern mechanical equipment. In order to meet the needs and development of aerospace, high-speed dynamic vehicles, and various defense special equipment, higher and higher requirements are made for the high precision and stability of gear transmission systems, as well as the prediction and control of noise and vibration. Considering the nonlinear factors such as comprehensive gear error and tooth side clearance, a dynamic model of the three-stage gear transmission system is established. The relevant physical parameters, geometric parameters, and load parameters in the gear system are considered random variables to obtain the stochastic vibration model. When the random part of the random parameters is much smaller than the deterministic part, the vibration differential equation is expanded into a first-order term at the mean of the random parameter vector according to the Taylor series expansion theorem, and the ordering equation is solved numerically. Based on the improved stochastic regression method, the nonlinear dynamic response analysis of the three-stage gear train is carried out. This results in a relatively stable system when the dimensionless excitation frequency is in the range of 0.716 to 0.86 and the magnitude of the dimensionless integral meshing error is

γ-Fe2O3 is considered to be a promising catalyst for the selective catalytic reduction (SCR) of nitrogen oxide (NOx). In this study, first-principle calculations based on the density function theory (DFT) were utilized to explore the adsorption mechanism of NH3, NO, and other molecules on γ-Fe2O3, which is identified as a crucial step in the SCR process to eliminate NOx from coal-fired flue gas. The adsorption characteristics of reactants (NH3 and NOx) and products (N2 and H2O) at different active sites of the γ-Fe2O3 (111) surface were investigated. The results show that the NH3 was preferably adsorbed on the octahedral Fe site, with the N atom bonding to the octahedral Fe site. Both octahedral and tetrahedral Fe atoms were likely involved in bonding with the N and O atoms during the NO adsorption. The NO tended to be adsorbed on the tetrahedral Fe site though the combination of the N atom and the Fe site. Meanwhile, the simultaneous bonding of N and O atoms with surface sites made the adsorption more stable than that of single atom bonding. The γ-Fe2O3 (111) surface exhibited a low adsorption energy for N2 and H2O, suggesting that they could be adsorbed onto the surface but were readily desorbed, thus facilitating the SCR reaction. This work is conducive to reveal the reaction mechanism of SCR on γ-Fe2O3 and contributes to the development of low-temperature iron-based SCR catalysts.

TG-FTIR and PY-GC/MS were used to analyze the pyrolysis behaviors of pine wood, urea-formaldehyde resin (UF resin) and their blended pellets. The pyrolysis process was divided into three stages: water evaporation, devolatilization and pyrolysis residue decomposition. During the pyrolysis process of the blended pellets, with the increase of the addition ratio of UF resin, the peak value of the weight loss decreased in the decomposition stage of the pyrolysis residue, while the temperature shifted to the low-temperature region. This was mainly due to the structural stability of pyrolytic carbon produced by UF resin, which hindered the thermal decomposition of lignin-produced residues in pine. FTIR showed that CO2 was the main product of pyrolysis. For UF resin, nitrogen compounds accounted for a large proportion. With the addition of UF resin, the nitrogen in the blended pellets increased significantly. Since the synergistic effect promoted the further decomposition of the organic oxygen-containing structure, the NO release was still increased. PY-GC/MS showed that co-pyrolysis produced more nitrogen-containing compounds and promoted the decomposition of macromolecular phenol derivatives, lipids and ketones, resulting in more small-molecule acids and alcohols.

Laser quenching is one of the most outstanding gear tooth surface quenching methods due to its high efficiency, environmental friendliness, and performance consistency. Since gear tooth surface laser quenching requires repeated scanning, changing the laser scanning velocity and power by program control can meet the needs of variable depth quenching. The effects of laser scanning velocity and output power on the quenching depth and surface Rockwell hardness after quenching were studied and experimentally analyzed. The result shows that by adjusting the parameters, the surface hardness of the specimen changes slightly with the actual received laser energy. However, the quenching depth can be consistent with the laser scanning velocity. The maximum surface Rockwell hardness that a laser quenched material can achieve depends on the material itself, not on the laser power or scanning velocity. Compared with accelerated laser quenching, decelerated laser quenching is more suitable for tooth surface machining due to the cumulative effect of energy within the quenching depth range of metal materials.

In this cross-sectional study, we studied performance of the International Severe Acute Respiratory and Emerging Infections Consortium mortality and deterioration scores in a cohort of 410 hospitalized patients (51.2% fully vaccinated). area under the receiver operating characteristic curves were 0.778 and 0.764, respectively, comparable to originally published validation cohorts. Subgroup analysis showed equally good performance in vaccinated and partially or unvaccinated patients.

LaMnO3 with perovskite structure is a SCR de-NOx catalyst with good performance at low temperatures. In this paper, the SCR reaction process on the 010 surface of LaMnO3 catalyst was studied by DFT method, to guide the development of catalysts and their effective application. The results obtained through research indicate that both E-R and L-H mechanisms exist on the catalyst surface. The NH3 molecule can be absorbed on L acid and then oxidized by lattice oxygen to form NH2. Then, NH2 can react with the NO molecule to form NH2NO and decompose to N2 and H2O. The NH3 can also be absorbed with hydroxyl to form NH4+, it can also react with NO to form NH2NO and then decompose. The NH4+ also can react with NO3− which is formed by NO oxidized when O2 is present, to participate in the rapid SCR process.

Purpose Considering the time-varying pressure angle and dynamic clearance, the effects of rotational speed, tooth surface friction, and tooth surface morphology on the system’s dynamic response are studied. Method An improved gear nonlinear model is proposed, which considered nonlinear factors such as time-varying pressure angle, position angle, tooth surface morphology, and tooth surface friction. The time-varying dynamic backlash is deduced, and the nonlinear dynamic equation of the gear is established. The nonlinear dynamic response of the gear system is obtained based on Runge–Kutta method. Results The influence of the rotational speed and tooth surface friction on single-stage spur gear system response is analyzed through the analysis of the bifurcation diagram, the three-dimensional spectrum diagram, the proportion of the meshing state, and the largest dynamic meshing force (LDMF). Dynamic response differences between the three different model are compared. In addition, by changing the tooth surface roughness and fractal dimension, the influence of tooth surface morphology on the dynamic response of the system is studied. Conclusion Compared with the traditional model, when the dynamic center distance and dynamic pressure angle are considered, the system response may enter a chaotic state earlier. When the tooth surface friction is further considered, the chaotic state of the system response is suppressed. At the same time, the velocity of the dynamic transmission error is significantly reduced, and the fluctuation amplitude of the dynamic pressure angle is increased. The value of LDMF rose overall. The stability of the system response decreases with the increase of tooth surface roughness and fractal dimension. Compared with the fractal dimension, the tooth surface roughness has a more obvious effect on the dynamic response of the system.

Guava (Psidium guajava L.) is a tropical fruit with great economic value. Guangdong is one of the most important guava production areas. In November 2019, guava wilt disease (GWD) was observed in a 10.6 HA commercial orchard in NanSha district, Guangzhou, Guangdong (22°37'37.626" N, 113°35'56.089" E). Disease incidence was up to 35%. Initially, leaves on the top of some branches became purple or yellow interveinal chlorosis, later dry. Infection severely became systemic developing vascular discoloration of stem, black root rot, eventually entire trees wilted and died. The root tissues were cut into 5-mm2 pieces and surface disinfected with 70% ethanol for 30 sec, 3 % sodium hypochlorite for 4 min, rinsed by the sterile water, then plated onto potato dextrose agar and incubated for 5 days at 25°C. A total of 8 monoconidial isolates with identical colony morphology were obtained. All formed cottony, whitish to pale yellow colonies. Conidiophores were dimorphic, penicillate and acremonium-like. Penicillate conidiophores gave rise to ovoidal, one-celled conidia (4.15 to 6.55×2.28 to 4.61 μm) (n=100) with truncated ends. Cylindrical or fusiform conidia (7.02 to 15.57×2.01 to 5.30 μm) (n=100) arose in long chains on acremonium-like conidiophores. Morphological characteristics of the isolates were consistent with those of Nalanthamala psidii (syn. Myxosporium psidii) reported by Schroers (2005). The rDNA internal transcribed spacer (ITS) and partial nuclear large-subunit ribosomal DNA (LSU) of two representative isolates (GDNS02 and GDNS08) were amplified using the primers pairs ITS4/ITS5 (White et al. 1990) and V9G/LR5 (de Hoog and Gerrits van den. 1998), respectively. The obtained sequences were deposited in GenBank under the accession nos. OM278372 to 73 (ITS) and OM278377 to 78 (LSU). BLASTn analysis showed 99.81% and 100% identities with the reported sequences of N. psidii CBS 116952 (AY864836) and CBS 110507 (AY554243). Maximum likelihood analyses of combined ITS and LSU sequences indicated that these two isolates being clustered with N. psidii strains. Pathogenicity tests were performed twice using healthy seedlings (60-70 cm height, cv. pearl). Each stem of five seedlings was wounded using a 5-mm sterile cork borer, and 5-day-old mycelium plugs of isolate GDNS08 were inoculated into the holes (25-cm above the soil line) and covered with Parafilm, sterile PDA plugs were placed into the wounds of additional 5 control seedlings. All plants were kept in a greenhouse (25℃, 80% relative humidity, 16/8-h day/night). After 3 months, all inoculated plants developed purple leaf, defoliation and wilt symptoms resembling those observed in the orchards, while the controls remained asymptomatic. Nalanthamala psidii was reisolated from the roots tissue of the inoculated plants, identity was confirmed by morphological characteristics and ITS sequence analyses as described above, but not from the controls, fulfilling Koch's postulates. Nalanthamala psidii has been previously reported as the causal agent of guava wilt in Taiwan, Philippines, South Africa and Bangladesh (Hsieh et al. 1976; Opina 1995; Schoeman et al. 1997; Alam et al. 2019). To our knowledge, this is the first report of N. psidii causing guava wilt in Guangdong, China. The outbreak of GWD in South Africa in the 1980s resulted in devastating losses to guava industry (Schoeman et al. 1997). Further research is needed to develop the integrated management to constrain this disease from spreading.

Guava (Psidium guajava L.) is a tropical fruit with great economic value. Guangdong is one of the most important guava production areas. In November 2019, guava wilt disease (GWD) was observed in a 10.6 HA commercial orchard in NanSha district, Guangzhou, Guangdong (22°37'37.626" N, 113°35'56.089" E). Disease incidence was up to 35%. Initially, leaves on the top of some branches became purple or yellow interveinal chlorosis, later dry. Infection severely became systemic developing vascular discoloration of stem, black root rot, eventually entire trees wilted and died. The root tissues were cut into 5-mm2 pieces and surface disinfected with 70% ethanol for 30 sec, 3 % sodium hypochlorite for 4 min, rinsed by the sterile water, then plated onto potato dextrose agar and incubated for 5 days at 25°C. A total of 8 monoconidial isolates with identical colony morphology were obtained. All formed cottony, whitish to pale yellow colonies. Conidiophores were dimorphic, penicillate and acremonium-like. Penicillate conidiophores gave rise to ovoidal, one-celled conidia (4.15 to 6.55×2.28 to 4.61 μm) (n=100) with truncated ends. Cylindrical or fusiform conidia (7.02 to 15.57×2.01 to 5.30 μm) (n=100) arose in long chains on acremonium-like conidiophores. Morphological characteristics of the isolates were consistent with those of Nalanthamala psidii (syn. Myxosporium psidii) reported by Schroers (2005). The rDNA internal transcribed spacer (ITS) and partial nuclear large-subunit ribosomal DNA (LSU) of two representative isolates (GDNS02 and GDNS08) were amplified using the primers pairs ITS4/ITS5 (White et al. 1990) and V9G/LR5 (de Hoog and Gerrits van den. 1998), respectively. The obtained sequences were deposited in GenBank under the accession nos. OM278372 to 73 (ITS) and OM278377 to 78 (LSU). BLASTn analysis showed 99.81% and 100% identities with the reported sequences of N. psidii CBS 116952 (AY864836) and CBS 110507 (AY554243). Maximum likelihood analyses of combined ITS and LSU sequences indicated that these two isolates being clustered with N. psidii strains. Pathogenicity tests were performed twice using healthy seedlings (60-70 cm height, cv. pearl). Each stem of five seedlings was wounded using a 5-mm sterile cork borer, and 5-day-old mycelium plugs of isolate GDNS08 were inoculated into the holes (25-cm above the soil line) and covered with Parafilm, sterile PDA plugs were placed into the wounds of additional 5 control seedlings. All plants were kept in a greenhouse (25℃, 80% relative humidity, 16/8-h day/night). After 3 months, all inoculated plants developed purple leaf, defoliation and wilt symptoms resembling those observed in the orchards, while the controls remained asymptomatic. Nalanthamala psidii was reisolated from the roots tissue of the inoculated plants, identity was confirmed by morphological characteristics and ITS sequence analyses as described above, but not from the controls, fulfilling Koch’s postulates. Nalanthamala psidii has been previously reported as the causal agent of guava wilt in Taiwan, Philippines, South Africa and Bangladesh (Hsieh et al. 1976; Opina 1995; Schoeman et al. 1997; Alam et al. 2019). To our knowledge, this is the first report of N. psidii causing guava wilt in Guangdong, China. The outbreak of GWD in South Africa in the 1980s resulted in devastating losses to guava industry (Schoeman et al. 1997). Further research is needed to develop the integrated management to constrain this disease from spreading.

The cochlea hair cells transform mechanic sounds to neural signals with a remarkable sensitivity and resolution. This is achieved via the precisely sculpted mechanotransduction apparatus of the hair cells and the supporting structure of the cochlea. The shaping of the mechanotransduction apparatus, the staircased stereocilia bundles on the apical surface of the hair cells, requires an intricate regulatory network including planar cell polarity and primary cilia genes in orienting stereocilia bundles and the building molecular machinery of the apical protrusions. The mechanism linking these regulatory components is unknown. Here we show that a small GTPase known for its role in protein trafficking, Rab11a, is required for ciliogenesis in hair cells during development in mice. In addition, in the absence of Rab11a, stereocilia bundles lost their cohesion and integrity, and mice are deaf. These data indicate an essential role of protein trafficking in the formation of hair cell mechanotransduction apparatus, implicating a role of Rab11a or protein trafficking in linking the cilia and polarity regulatory components with the molecular machinery in building the cohesive and precisely shaped stereocilia bundles.Significance StatementOur research discovered for the first time that the small GTPase Rab11a is required for ciliogenesis, and for the precise patterning and cohesion of the stereocilia bundles in cochlear hair cells.

Dentin matrix protein 1 (Dmp1) is a highly phosphorylated, extracellular matrix protein that is extensively expressed in bone and teeth but also found in soft tissues, including brain and muscle. However, the functions of Dmp1 in the mice cochlea are unknown. Our study showed that Dmp1 was expressed in auditory hair cells (HCs), with the role of Dmp1 in those cells identified using Dmp1 cKD mice. Immunostaining and scanning electron microscopy of the cochlea at P1 revealed that Dmp1 deficiency in mice resulted in an abnormal stereociliary bundle morphology and the mispositioning of the kinocilium. The following experiments further demonstrated that the cell-intrinsic polarity of HCs was affected without apparent effect on the tissue planer polarity, based on the observation that the asymmetric distribution of Vangl2 was unchanged whereas the Gαi3 expression domain was enlarged and Par6b expression was slightly altered. Then, the possible molecular mechanisms of Dmp1 involvement in inner ear development were explored via RNA-seq analysis. The study suggested that the Fgf23–Klotho endocrine axis may play a novel role in the inner ear and Dmp1 may regulate the kinocilium–stereocilia interaction via Fgf23–Klotho signaling. Together, our results proved the critical role of Dmp1 in the precise regulation of hair bundle morphogenesis in the early development of HCs.

Staphylococcus aureus is a bacterium that causes various diseases in humans. Cold plasma is found to be an alternative to eliminate S. aureus. Most studies of cold plasma on S. aureus mainly focus on the physiochemical changes of the cells. So far, biological responses of S. aureus to cold plasma treatment under different treatment durations have not yet been evaluated. In this study, the results showed that the cold plasma was effective in eliminating S. aureus. At the initial exposure (1 min), the treated cells showed gene upregulations of stress proteins, antioxidants, nitrosative stress, and transporter proteins, but no significant change in other biological processes, such as cell membrane synthesis, DNA repairing, transcription, and translation. This indicated that the cells actively countered the damage from cold plasma. In contrast, during the prolonged treatment (3 and 5 min), biological processes related to central dogma were affected, including the DNA repairing mechanism, transcription, and translation. In addition, the majority of the genes related to cell membrane synthesis were downregulated, indicating that the treated cells could no longer sustain their cell integrity. In conclusion, this study elucidated how cold plasma inactivated S. aureus in a series of cold plasma exposures and highlighted the sequential transcriptomic responses of S. aureus.

The Internet of Things (IoT) networks have been adopted ubiquitously to support domain applications. Specially, social robots have become an important part of IoT networks as smart devices and are widely used to support versatile domain applications. In this setting, gathering sensory data from social-aware mobile robots in an energy-efficient manner is of importance for prolonging the network lifetime and promoting proper decision-making. Considering the large-scale and spatial-temporal evolutional characteristic of IoT networks, social robots roam over time to deal with tasks, especially when considering fact that it may hardly be predicted for the regions and time durations that certain anomalies may occur. Therefore, this paper proposes to adopt mobile edge computing to support sensory data gathering. Edge nodes in edge networks gather sensory data from their subordinating social robots in a periodic manner. We design an edge network division method by constructing an improved Sort-Tile-Recursive (STR) tree, which can cluster the edge nodes and decrease unnecessary energy consumption. Experimental results show that our technique is more efficient than traditional ones in decreasing energy consumption.

The catalytic NO removal efficiencies of MnFeOx/SiO2 catalysts with different Fe/Si were compared and studied. The reaction pathway analysis of NH3-SCR on the surface of MnFeOx/SiO2 catalyst was performed based on DFT calculations. The experimental results of catalytic activity show that the addition of an appropriate amount of iron oxide has significant improvement for the NO conversion from 240 °C to 330 °C and the N2 selectivity from 150 °C to 330 °C. The XRD test also shows that the addition of iron oxide can greatly improve the dispersion of MnO2. In addition, DFT calculations indicate that the main process of N2 formation is the NH2NO decomposition and N-NO reaction. The N-NO reaction to form N2 is a unique reaction pathway possessed by MnFeOx/SiO2, which is the main reason for the high NO conversion and good N2 selectivity of MnFeOx/SiO2 catalyst and shows good synergy between manganese oxide and iron oxide.

The combustion mechanism of biogas mixture is unclear, which leads to the lack of basis for the control of operating parameters. Combustion characteristics and reaction path of typical low calorific value biogas with variation of preheating temperature and air equivalence ratio (Φ) are discussed in this paper. Preheating can not only improve the flame propagation speed and flame temperature, but also increase the proportion of NO in the product at the end of combustion flame. To some extent, improving combustion efficiency and NOx control are contradictory operating parameters. The amount of NO increases with the increase in flame distance. The maximum value of NO appears when Φ is 1.1. NO formation rate is improved by preheating the biogas. The paths of N2 → N2O →NO, N2 → NNH →NO, and N2 →NO are all enhanced. When the equivalence ratio changes from 1.0 to 0.8, NO formation rates decrease.

Hair cells in cochlea and vestibular organs depend on the coordinated cell polarity to perform the normal auditory or balance function. The mouse inner ear is one of the ideal model to study planar cell polarity. In this chapter, we introduce a series of general experimental methods for studying planar cell polarity in the inner ear. The approaches presented here are also applicable to other organs with particular polarity phenotypes.

In order to study the effect of biomass on the pyrolysis characteristics of urea-formaldehyde resin, the thermogravimetric experiments were carried out respectively using urea-formaldehyde resin (UF), rice straw (RS), and their mixed pellets with different proportions. The pyrolysis kinetics analysis was conducted. The results showed that the pyrolysis process of UF resin and mixed pellets could be divided into three stages: the drying and dehydration of the material, the rapid decomposition of volatile matter, and residue decomposition. The reaction order of UF resin and mixed pellets was discussed using the Coats–Redfern method, the activation energy of UF resin was 54.27 kJ/mol, and this value decreased with the addition of rice straw. As the mass ratio of UF resin to rice straw was 3:1, the activation energy achieved the lowest value, which means that the addition of rice straw was beneficial to the pyrolysis process of UF. In the process of pellet preparation, the falling strength and compressive strength of UF resin pellets can be improved by adding an appropriate proportion of rice straw. In this test, the yield of pyrolytic carbon reached the highest value of 23.93%, as the mass ratio of UF resin to rice straw was 3:2. When the mass ratio was 4:1, the highest liquid product yield of 43.21% was achieved.

Data on use of monoclonal antibodies (mAbs) in hospitalized patients are limited. In this cross-sectional study, we evaluated the use of mAbs for early treatment of unvaccinated hospitalized patients with mild-to-moderate COVID-19. All inpatients at our center were screened on 27 October 2021. Primary outcome was in-hospital deterioration as defined by a composite of oxygen requirement, intensive care unit (ICU) admission, or mortality within 28 days of admission. Ninety-four out of 410 COVID-19 inpatients were included in the final analysis, of whom 19 (20.2%) received early treatment with sotrovimab. The median age was 73 years (IQR 61–83), and 35 (37.2%) were female. Although the treatment group was significantly older and had more comorbidities, there was a lower proportion of progression to oxygen requirement (31.6% vs. 54.7%), ICU admission (10.5% vs. 24.0%), or mortality (5.3% vs. 13.3%). Kaplan–Meier curves showed a significant difference in time to in-hospital deterioration (log-rank test, p = 0.043). Cox proportional hazards model for in-hospital deterioration showed that sotrovimab treatment was protective (hazard ratio, 0.41; 95% CI, 0.17–0.99; p = 0.047) after adjustment for baseline ISARIC deterioration score. Our findings support the use of sotrovimab for early treatment in hospitalized patients with mild-to-moderate COVID-19 at a high risk of disease progression.

Firstly, the polyvinyl alcohol/polyacrylic acid double network hydrogels were prepared by physical and chemical double cross-linking, then polyethylene glycol, chitosan, and hydroxypropyl methyl ce...

Based on the density functional theory, the adsorption processes of NH3, and NO and O2 on the Mn active sites of MnOx/SiO2 β-cristobalite (101) surface were simulated. The results show that NH3, NO and O2 can be effectively adsorbed on the Mn active sites of both MnO2/SiO2 β-cristobalite (101) and Mn2O3/SiO2 β-cristobalite (101) surface. The adsorption characteristics of the two catalysts are different. The adsorption energy of NH3 molecule on the MnO2/SiO2 β-cristobalite (101) surface is much higher than that on the Mn active sites of Mn2O3/SiO2 β-cristobalite (101) surface. The NO molecule and the O2 molecule are a little easier to be adsorbed on the Mn active sites of Mn2O3/SiO2 β-cristobalite (101) surface. The large difference of NH3 adsorption energy between the two catalysts becomes one of the main reasons why MnO2/SiO2 has better catalytic activity than Mn2O3/SiO2. Furthermore, the high adsorption energy of NH3 on MnO2/SiO2 surface proves that SiO2 is an excellent carrier and MnO2/SiO2 catalyst is an outstanding NH3-SCR catalyst at low temperature.

The low-temperature catalytic NO removal efficiencies of catalysts with two different manganese precursors, manganese acetate (αMA catalyst) and manganese nitrate (αMN catalyst), were compared and studied. The NH3-SCR of NO tests using these catalysts were carried out in a self-made reaction device to measure the catalytic activity of the catalysts. Moreover, the reaction pathway analysis of NH3-SCR of NO on the surface of MnO2/SiO2 catalyst and Mn2O3/SiO2 catalyst were performed based on DFT calculations individually. The experimental results show that the NO conversion of αMN catalyst is higher than the αMA catalyst at low temperature (

Many factors can cause inner ear injury, such as noise exposure, chemicals, viral infection, and radiation. The main pathological manifestations of inner ear injury are local hypoxia-ischemia, micro-trauma, and an increased level of reactive oxygen species and inflammatory mediators. The contribution of the inflammatory response to the mediation of cochlear and vestibular pathologies has received increasing attention in recent years. Aseptic inflammation can devastate audition and balance, which can lead to many typical clinical inner ear diseases. In this review, we will discuss the most pertinent and recent research on inflammatory mechanisms in inner ear injury. We will also discuss the pathophysiology of some common and significant ear diseases, such as sudden sensorineural hearing loss, age-related hearing loss, noise-induced hearing loss, and Meniere's disease.

Copper slag is a solid pollutant with high recyclability. Reduction and separation are regarded as effective disposal methods. However, during the melting process, the separation and migration behavior of elements in the copper slag is complicated. Thus, the formation of pollutants cannot be controlled merely by optimizing the operation parameters. The elemental distribution and migration behavior are discussed in this work. In reduction experiments, the copper slag smelting liquid was divided into three layers: a reduction slag layer, a reactive boundary layer, and an iron ingot layer. Reduction slag and ingot iron were on the top and bottom of the liquid, respectively. Residual carbon oozed at the interface. C can react with reducible “O” atoms, which exist in 2FeO·SiO2, Fe3O4, and CuO. Meanwhile, CO was generated and overflowed from the liquid layer. After reduction by C or CO, metallic iron and copper were produced and migrated to the iron ingot layer. In the liquid, S gradually diffused into the upper layer. Some of the ZnO and CuS spilled from the liquid into the flume. After reduction, CaO·SiO2 was generated and moved to the upper layer.

Copper slag, an important by-product of the copper smelting process, is mainly composed of 2FeO SiO2, Fe3O4, and SiO2. Due to the sufficient metal oxides, copper slag is regard as a potential oxygen carrier (OC), which can be applied in chemical looping technology. This research proposed to use the granulated copper slag particles as precursor to produce oxygen carrier. Through this method, waste heat of the high-temperature slag can be fully recovered, eliminating the complicated copper slag pretreatment process. In this paper, the reactivity of granulated copper slag after redox calcination was studied by X-ray diffractometer (XRD) and Scanning Electron Microscope (SEM), the highest reactivity occurred at 1,000°C. In addition, the oxygen release and absorption performance of OC were tested in thermal-gravimetric (TG). According to theoretical calculations, the mass loss caused by oxygen release accounts for 70.57% of the total loss and the mass reached by 4.2% at 1,000°C in oxygen absorption experiment. The copper slag modified through calcining in redox condition was proved to be a promising oxygen carrier in chemical looping process. Furthermore, the performance research on OC also provided theoretical references for the operating paraments of OC circulating between air reactor and fuel reactor in practical chemical looping processes.

Rack1 features seven WD40 repeats that fold into a multifaceted scaffold used to build signaling complexes in a context-dependent manner. Previous in vitro studies have revealed associations between Rack1 and many other proteins. Rack 1 is required for establishing planar cell polarity (PCP) in zebrafish and Xenopus. However, any molecular role of Rack1 in protein complexes or polarity regulation remains unclear. Here, we show that Rack1 is an essential gene in mice. Conditional knockout of Rack1 shortened the cochlear duct and induced cellular patterning defects characteristic of defective convergent extension (this PCP process is mediated by cellular junctional remodeling in the developing cochlear epithelium). Also, cochlear hair cells were no longer uniformly oriented in Rack1 conditional knockout mutants. Rack1 was enriched in the cellular cortices of sensory hair cells. In Rack1-deficient cochleae, E-cadherin expression at the cellular boundaries was greatly reduced. Together, the findings reveal a molecular role of Rack1 in PCP signaling that likely involves modulation of E-cadherin levels at the adherens junctions of the plasma membrane.

In this paper, we propose an innovative approach, called Dense Nested Attention Network (DNANet), to directly restore a clear image from a hazy image with a new topology of connection paths. Firstly, through dense nested connections from inside to outside, the DNANet can fuse both shallow and deep features from fine to coarse, then strengthen the feature propagation and reuse to a large extent. We use stacked dilated convolutions, as the basic operation, to alleviate the shortcomings of the traditional context information aggregation methods. Secondly, we examine the weakness of skipping connections by reasoning the existence of residual haze from the shallow to deep layers in the neural network. To address this problem, we use the attention mechanism to filter out the output of residual haze by capturing the information relations on the entire skip feature maps. Thirdly, we introduce an adjustable loss constraint on each block of the outermost nested structure to gather more accurate features. The result demonstrates that DNANet outperforms state-of-the-art methods by a large margin on the benchmark datasets in extensive experiments.

The adsorption process is the first step and a crucial step in the SCR NOx removal. The adsorption characteristics of NH3, NOx on the surface of the catalyst is very important on the understanding the catalytic mechanism of low-temperature catalysts. In this paper, therefore, the adsorption of NH3, NOx and some other small molecules on the surface of the nano-γFe2O3 was studied by using the first principle and density functional theory (DFT). Particularly, the adsorption processes, in which the NH3 and NOx molecules were adsorbed at different active sites of the nano-γFe2O3 catalyst surface, were evaluated and analyzed. The computational results show that octahedral Fe cation of nano-γFe2O3 is the most active site and many kinds of molecules can be adsorbed to the octahedral Fe cation. On the adsorption of NH3, the adsorption energy of Fe N configuration is large and the configuration is stable. When O-defects are present on the surface, the adsorption energy of Fe N configuration will be promoted. On the NOx adsorption process, the adsorption products are more complicated. It can be adsorbed on both the perfect surface and the O-defective surface to form many products. The H2O and N2 can also be adsorbed on the surface of nano-γFe2O3 but the adsorption energy is small. This ensures that H2O and N2 as product can be desorbed from the catalyst surface easily.

The key bottleneck problem of chemodynamic therapy (CDT) is that the efficiency depends heavily on an acidic chemical environment. However, there is a sufficient blood supply on the surface of solid tumours, resulting in neutral-pH surface regions, strongly reducing the effectiveness of CDT. In this study, chelating complex ferrous-cysteine–phosphotungstate nanoparticles (FcPWNPs) are synthesized to serve as new CDT nanoagents that break through the limitation of a neutral pH, ensuring CDT efficiencies at both an acidic and neutral pH. The CDT efficiency is increased by introducing cysteine and phosphotungstate, which form an Fe chelating complex to inhibit the formation of inert Fe(OH)x, and accelerate electron transfer between ferric and ferrous ions, respectively. Due to this ferrous chelating strategy and associated electron transfer property, the FcPWNPs can destroy cancer cells from the neutral-pH tumour surface to the acidic interior, thus realizing a complete CDT cancer therapy.

Objectives: Predictive scores are important tools for the triage of patients with coronavirus disease 2019. The PRIORITY score is advantageous because it does not require laboratory and radiologic information. However, the original development and validation cohorts studied only unvaccinated patients in early 2020. We aimed to externally validate the PRIORITY score in a cohort of patients with the novel delta and omicron variants of coronavirus disease 2019 and mixed vaccination status. Methods: A total of 410 patients were included in a cross-sectional sampling of all patients admitted to the National Centre of Infectious Diseases on October 27, 2021. A further 102 and 136 patients with vaccine-breakthrough Delta and Omicron variant infection from April to August and December 2021, respectively, were also included. Variables at the time of admission were collected retrospectively from medical records and used to calculate the probability of deterioration using the PRIORITY model. Results: Of the total 648 included patients, 447 (69.0%) were vaccinated. The mean age was 61.6 years (standard deviation ± 19.0 years), and 268 patients (41.4%) were female. A total of 112 patients (17.3%) met the primary outcome of developing critical illness or mortality. The performance of the score in this cohort was comparable with the original cohorts, with an area under the receiver operating characteristic curve for all patients of 0.794 (95% CI, 0.752e0.835; p < 0.001), regression coefficient of 1.069, and intercept of 0.04. Subgroup analysis of unvaccinated and vaccinated patients showed that performance was superior in vaccinated individuals, with an area under the receiver operating characteristic curve of 0.684 (95% CI, 0.608e0.760; p < 0.0001) and 0.831 (95% CI, 0.772e0.891; p < 0.0001), respectively. Discussion: Our data support the continued use of the PRIORITY score in this era of novel variants and increased vaccination uptake. BEY reports personal fees from Roche and Sanofi outside of the submitted work. All other authors declare no competing interests. No additional funding was required for this study.

Although, biomass energy is a renewable energy are gradually advocating and studying widely, it is urgent to develop efficient biomass technology and reduce NOx emissions. The combustion mechanism of biogas mixture is unclear, which leads to the lack of basis for the control of operating parameters. Combustion characteristics and reaction path of typical low calorific value biogas with variation of preheating temperature and air equivalence ratio (Φ) are discussed. With the increase of preheating temperature, the final flame temperature moves up. Preheating of biogas can not only improve the flame propagation speed and flame temperature, but also increase the proportion of NO in the product at the end of combustion flame. To some extent, improving combustion efficiency and NOx control are contradictory in operating parameters. The amount of NO formation increases with the increase of flame distance. The maximum value of NO appears when Φ is 1.1. NO formation rate is improved by preheating of the biogas. The paths of N 2 → N 2 O →NO, N 2 → NNH →NO and N 2 →NO) are all enhanced. When the equivalence ratio changes from 1.0 to 0.8, the NO formation rates of the three reaction paths decrease

Low-dose computed tomography image denoising is a challenging task that has been studied by many researchers. Current denoising methods based on deep learning tend to produce a blur effect on the final results, especially at high noise levels, which are prone to over-smoothed edges and loss of details. In this paper, we propose a deep learning approach based on deep convolutional and edge constraints to mitigate these problems. Firstly, to avoid the loss of shallow layers details while obtaining semantically-richer features information, we use dilated convolution instead of standard convolution, and fusion feature maps of different levels to aggregate information from different receptive field. Secondly, in order to improve the network's ability to distinguish between noise and image content, we have designed an attention block to adaptively recalibrate the information relationship of the fusion feature maps. Finally, we incorporate edge prior knowledge into LDCT image denoising task, guiding the network to pay more attention on texture and structure information by edge constraints loss. Extensive experiments demonstrate that the proposed method achieves significant improvements over the state-of-the-art methods.