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Abstract Background Treacher Collins syndrome (TCS; OMIM 154500) is a craniofacial developmental disorder. Methods To investigate the genetic features of a four-generation Chinese family with TCS, clinical examinations, hearing tests, computed tomography, whole-exome sequencing (WES), Sanger sequencing, reverse transcription (RT)-PCR, and the Minigene assay were performed. Results The probands, an 11-year-old male and his cousin exhibited typical clinical manifestations of TCS including conductive hearing loss, downward slanting palpebral fissures, and mandibular hypoplasia. Computed tomography revealed bilateral fusion of the anterior and posterior stapedial crura and malformation of the long crura of the incus. WES of both patients revealed a novel heterozygous intronic variant, i.e., c.4342 + 5_4342 + 8delGTGA (NM_001371623.1) in TCOF1. Minigene expression analysis revealed that the c.4342 + 5_4342 + 8delGTGA variant in TCOF1 caused a partial deletion of exon 24 (c.4115_4342del: p.Gly1373_Arg1448del), which was predicted to yield a truncated protein. The deletion was further confirmed via RT-PCR and sequencing of DNA from proband blood cells. A heterozygous variant in the POLR1C gene (NM_203290; exon6; c.525delG) was found almost co-segregated with the TCOF1 pathogenic variant. Conclusions In conclusion, we identified a heterozygous TCOF1 splicing variant c.4342 + 5_4342 + 8delGTGA (splicing) in a Chinese TSC family with ossicular chain malformations and facial anomalies. Our findings broadened the spectrum of TCS variants and will facilitate diagnostics and prognostic predictions.

Taking the Yili mining area in Xinjiang as an example, combined with the typical hydrogeological characteristics of the Tianshan Mountains, such as strong snowmelt runoff and uneven permeability of Jurassic coal-rich strata, the macroscopic hydrogeological conditions, microscopic water-bearing media characteristics and water-rich law of the main aquifers (aquicludes) layers in the mining area were systematically studied by means of field sampling, electron microscope scanning, mercury injection experiment, X-ray diffraction and pumping test. The hydrodynamic characteristics and migration law of aquifers under special stratigraphic and geomorphological conditions are revealed. The results show that the effective porosity range of the sandstone aquifer in the roof and floor of the Jurassic main coal seam in the study area is 17.1%-29.5%, and the effective porosity range of the Neogene and Jurassic aquiclude is 17.6%-29.0%. The aquifers (aquicludes) layer contains high clay minerals, which are expanded and argillized in water. The special microstructure and mineral composition make the aquifers (aquicludes) layer show the characteristics of high porosity and poor permeability. In the study area, the water abundance of the Quaternary pore aquifer and the Jurassic main coal seam roof and floor sandstone aquifer is weak, and some areas show moderate water abundance, mainly static reserves, with block characteristics. The hydrodynamic characteristics and migration law of the main aquifers (aquicludes) are systematically studied. The Quaternary system is affected by the macro-geomorphology and hydrogeological conditions of the piedmont, showing the dynamic characteristics of ‘slope transit flow’ in the form of pore phreatic water with high intensity flow. At the same time, it is blocked by the lower Neogene mudstone aquifuge and has no hydraulic connection with the sandstone aquifer of the roof of the coal measures. The sandstone aquifer of the 5# coal seam floor mainly affects the coal seam mining, in view of this layer, the “factory” shape of “lateral closure and lateral cover” was constructed in a large range and the dredging effect was remarkable, which created good hydrogeological conditions for underground mining. The relevant research results reveal the characteristics of special water-bearing media and the law of water storage and water control formed by the Jurassic coal-rich strata in the study area under the influence of sedimentary environment, which can provide certain theoretical and engineering basis for water prevention and control under similar mining conditions in the study area and western mining area.

Perovskite SCR catalysts have become a hot research topic in the field of de-NOx catalyst development. This article selects LaMnO3 with high performance as the research object, modifies the catalyst by doping some iron elements instead of manganese elements, and applies density functional theory to study its reaction mechanism, providing theoretical reference for further research on perovskite. Research has found that several main reactants such as NH3, NO, and O2 can form stable adsorption at the active site, with NO more inclined to adsorb at the nitrogen atom end at the active site. The oxidation of O2 molecules after adsorption is greater than that of the active site. The adsorption capacity of the Mn active site of the catalyst before modification on the above molecules is weaker than that of the Fe active site introduced after modification. Under both anaerobic and aerobic conditions in the SCR reaction process, NH3 molecules are first adsorbed at the active site, and then influenced by lattice oxygen under anaerobic conditions. Under aerobic conditions, they are gradually dehydrogenated and produce NH2 and NH radicals. These two radicals react with NO molecules to form intermediate products in the form of NH2NO and NHNO molecules. Due to the instability of the intermediate products, they ultimately decompose into N2 and H2O molecules. The introduction of Fe active sites can increase the generation of NH2 and NH radicals during the reaction process and simplify the reaction process between NH2 radicals and NO molecules, which will be conducive to the completion of the reaction.

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.

The inner surface defects can be displayed intuitively by measuring the geometric parameters of rifling of the artillery barrel. In this paper, the parameters of the barrel bore were scanned based on the high-precision laser, and the three-dimensional reconstruction of the bore shape was conducted based on the test data. The wavelet transform was used for multiple de-noising of the test data, and the Delaunay triangulation interpolation algorithm was used to reconstruct the three-dimensional contour structure of the barrel bore, forming a high-fidelity measurement strategy for the parameters of the barrel bore. The results show that this measurement strategy can achieve the high-precision measurement of the geometric parameters of barrel rifling, and the accuracy can reach .001 mm. By comparing the measured value of rifling with the standard value, the flaw points in the rifling of the birth tube can be accurately specified. The three-dimensional model reconstruction based on the massive sample data realizes the high-fidelity measurement of rifling geometric parameters. This measurement strategy can provide support for the visualization of barrel rifling and effectively improve the detection accuracy of the barrel bore.

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.

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.

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.

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.

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.

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.

Abstract. 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.

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.

As part of the inner ear, the vestibular system is responsible for sense of balance, which consists of three semicircular canals, the utricle, and the saccule. Increasing evidence has indicated that the noncanonical Wnt/PCP signaling pathway plays a significant role in the development of the polarity of the inner ear. However, the role of canonical Wnt signaling in the polarity of the vestibule is still not completely clear. In this study, we found that canonical Wnt pathway-related genes are expressed in the early stage of development of the utricle and change dynamically. We conditionally knocked out β-catenin, a canonical Wnt signaling core protein, and found that the cilia orientation of hair cells was disordered with reduced number of hair cells in the utricle. Moreover, regulating the canonical Wnt pathway (Licl and IWP2) in vitro also affected hair cell polarity and indicated that Axin2 may be important in this process. In conclusion, our results not only confirm that the regulation of canonical Wnt signaling affects the number of hair cells in the utricle but also provide evidence for its role in polarity development.

Background: Middle ear adenoma (MEA) is a rare primary tumor of the middle ear. Clinical and radiological findings are non-specific and rarely suggestive of this condition. In order to find out the common specific characteristics of MEA and assist in preoperative diagnosis, we conducted this study. Methods: Three patients with pathologically confirmed MEA were treated in our hospital from January 2018 to February 2022. We collected and analyzed computed tomography (CT) and magnetic resonance imaging (MRI) data of them, and we fused T1 enhancement sequences of MRI and CT and made a 3-dimensional reconstruction with 3D Slicer. We also compared preoperative images with intraoperative findings. Results: We found that all MEA lesions of the tympanum were located between the manubrium of the malleus and the ostium tympanicum tubae auditivae. This was different than the common site of the paraganglioma or the cholesteatoma; the results were confirmed in subsequent surgical operations. We also found that the otoscopic appearances of MEA were special. Conclusion: The results indicate that MEA may mainly occur near the ostium tympanicum tubae auditivae. As the tumor grows, it may invade backward or outward into the external auditory canal. Clinicians can identify MEA early through its spatial location in CT and MRI. [ABSTRACT FROM AUTHOR]

Objectives: This study compared the rate of graft success, as well as hearing improvement and dry ear time between dry ears and wet ears with otomycosis or without otomycosis in patients with chronic suppurative otitis media (CSOM) after endoscopic cartilage myringoplasty. Methods: This retrospective study was conducted in a tertiary hospital in Shanghai. In total, 83 patients with CSOM (43 with dry ears and 40 with wet ears) were included. Among the 40 patients with CSOM and wet ears, 25 exhibited otomycosis. All patients underwent endoscopic myringoplasty, and perforations were repaired using tragal cartilage with a singlesided perichondrium. Patients were followed up for at least 6 months. Pure-tone hearing was examined preoperatively and at 3 months postoperatively. The graft uptake rate, hearing improvement, and dry ear time were compared between the groups. Results: The graft success rate did not differ significantly between the dry-ear and wet-ear groups (95.35% and 90.00%, respectively). Furthermore, the graft success rate also did not differ significantly between patients with wet ears and otomycosis and those with wet ears without otomycosis (92.00% and 86.67%, respectively). Hearing gain did not differ significantly between the dry-ear and wet-ear groups. No significant difference in hearing gain was also found in patients with wet ears with or without otomycosis. However, the time to dry ear was significantly longer in the wet-ear group than in the dry-ear group. Conclusion: Patients with CSOM and wet ears required more time to achieve a completely healthy status. However, the graft success rate and hearing improvement were not affected by a wet middle ear and otomycosis. Thus, endoscopic myringoplasty using tragus cartilage is an effective treatment for refractory CSOM in patients with wet ears and otomycosis. [ABSTRACT FROM AUTHOR]