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Abstract: Purpose: To explore the outcomes of lateral attic wall (LAW) reconstruction using autogenous mastoid cortical bone in cases with poorly developed zygomatic root cells and/or a low tegmen or with significant anterior or lateral sigmoid sinus in tympanomastoid surgery. Material and methods: Thirty-five ears with chronic suppurative otitis media, all of them either with poorly developed zygomatic root cells and/or a low tegmen (26/35 ears), or with significant anterior or lateral sigmoid sinus (9/35 ears), were included. LAWs were removed temporarily to offer exposure of the attic; after removal of the pathological conditions in the attic and the mastoid, LAW was reconstructed using autogenous mastoid cortical bone. The condition of the reconstructed LAW and tympanomastoid aeration was evaluated by computed tomographic scan or/and otoendoscopy. Results: The pathological conditions in the attic, the antrum, and the mastoid could be removed with safety in all cases; no serious complications occurred, the new canal appeared to be of normal size and shape, and no dislocation or necrosis of the repaired part was noted. Most of the cases had no significant attic retraction and kept good tympanomastoid aeration postoperatively. Conclusion: The reconstruction of LAW is especially suited to the cases in our study, and the reconstructed LAW can produce an almost normal anatomical external auditory canal, prevent the formation of attic retraction, and restore the mastoid cavity aeration in most of the cases. [Copyright &y& Elsevier]

Cytochrome P450 (CYP450) is a well-known protein family that is widely distributed in many organisms. Members of this family have been implicated in a broad range of reactions involved in the metabolism of various organic compounds. Recently, an increasing number of studies have shown that the CYP450 enzyme also participates in the elimination and degradation of organic pollutants, by white rot fungi (WRF), a famous group of natural degraders. This paper reviews previous investigations of white rot fungal CYP450 involved in the biodegradation of organic pollutants, with a special focus on inhibitory experiments, and the direct and indirect evidence of the role of white rot fungal CYP450 in bioremediation. The catalytic mechanisms of white rot fungal CYP450, its application potential, and future prospect for its use in bioremediation are then discussed. [Display omitted] • Reviewed the role of CYP450s in the biodegradation of organic pollutants by WRF. • The inhibitory experiments and the evidence for WRF CYP450s in bioremediation were presented. • Discussed the catalytic mechanisms of WRF CYP450s in organic pollutants biodegradation. [ABSTRACT FROM AUTHOR]

The endoscopic endonasal approach (EEA) has been applied in the treatment of olfactory neuroblastoma (ONB). However, there is a lack of research examining the impact of EEA on locally advanced ONB. This study assessed the outcomes of EEA in patients with locally advanced ONB and its impact on the quality of life (QOL). We retrospectively reviewed patients with Kadish stage C ONB who underwent EEA between December 2004 and October 2019 and assessed demographic data, histopathologic grade, the extent of resection, postoperative complications, and outcomes. Preoperative and postoperative QOL was assessed using the Sino-Nasal Outcome Test. Twenty-six patients (18 men, 8 women; aged 26–79 years) were enrolled, with 12 cases of Hyams grade II and III and 1 case of grade I and IV each. In total, 25 patients received radiotherapy and 16 patients received chemotherapy, of whom 11 received preoperative neoadjuvant chemotherapy. Postoperative nasal bleeding was observed in 2 patients. The follow-up ranged from 8 to 124 months (median, 42.3 months). The 1-year and 5-year overall survival were 96.2% and 84.8%, respectively. The 1-year and 5-year disease-free survival were 76.9% each. The analysis of the postoperative Sino-Nasal Outcome Test scores showed significant improvement in certain psychological and sleep-associated domains, compared with the preoperative scores. Our results showed that pure EEA followed by radiotherapy offered excellent outcomes in the management of selected patients with locally advanced ONB. The postoperative QOL was significantly improved. More research is required on neoadjuvant chemotherapy to establish its role. [ABSTRACT FROM AUTHOR]

The effect and mechanism of particulate matter capture and migration in activated carbon sintering flue gas purification system. [Display omitted] • The material flow analysis of K was established. • The release of AC is a key link affecting the concentration of flue gas particles. • The sintered ash is captured by AC via inertial collision and interception diffusion sedimentation. • The sintered ash remove via AC is an important solution of ultra-low emission. By using alkali metal K as the tracer component of sintered ash, the particulate matter (sintered ash and activated carbon powder) in the industrial two-stage moving bed purification project of sintered flue gas was studied. First, the distribution of K element in the gas phase and each link of the purification system was investigated. The material flowing direction as well as the trapping and releasing mechanism of sintered ash in the purification system were analyzed by BET, XRD, and SEM-EDS techniques. The migration and release rule of activated carbon (AC) powder from moving bed to gas phase was investigated, and the contribution of AC powder to flue gas particles and the key release link were clarified. The results showed that the sintered ash capture rate in the primary adsorption tower of AC was as high as 99.7%, while 65.92% of the sintered ash was captured in the middle chamber of the primary adsorption tower. Sintered ash is trapped by AC at 0–0.5 mm on the surface, which suggested the main trapping mechanisms are inertial collision and interception diffusion settling. The trapped sintered ash is recycled through the system with the AC, and eventually 99.9% ash is discharged with the sieved carbon powder from the desorption tower. The percentage of charcoal powder in the exit flue gas particulate matter is 55.45% and the release of activated charcoal powder to the gas phase in the secondary adsorption tower. Which is the key link affecting the exit flue gas particulate matter concentration. This study elucidates the capture and migration law of particulate matter in AC flue gas purification system, and provides a strong basis for the improvement of technology to achieve stable ultra-low emission of particulate matter from AC system. [ABSTRACT FROM AUTHOR]

In recent years, Hg re-emission from the wet scrubber has become a hot topic in the field of Hg abatement since wet scrubber has been considered as an effective way to remove Hg. In this paper, the effects of Cu ions on Hg re-emission were investigated for the first time in the presence of SO 3 2− . The effect of CuCl 3 2− was proved to directly reduce Hg 2+ to insoluble Hg 0 and to catalytically decompose Hg(SO 3 ) 2 2− to Hg 0 and SO 4 2− in the presence of SO 3 2− . When adding the Cu 2+ into solution with low concentration, Hg re-emission was increased due to the generation of Cu + from the reduction of Cu 2+ by SO 3 2− . Further increase of Cu 2+ concentration inhibited Hg re-emission, which was possibly owing to the formation of metal Cu which could absorb Hg 0 to form amalgam. The decomposition of Hg(SO 3 ) 2 2− by CuCl 3 2− and Cu + meet pseudo-first-order reaction with respect to Hg 0 and the activation energy parameters are 64.43 and 48.78 kJ/mol, respectively. Difference of electron transfer path in the decomposition of Hg(SO 3 ) 2 2− with Cu + was proposed to be the reason of low activation energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Iron precipitates at different oxidation degrees are obtained by H 2 O 2. • Ms value of Fe 3 O 4 shows a decrease and then recovery with oxidation. • Magnetic properties are affected via a Fe-O bond length-related mechanism. • The "magnetic iron oxides" method is promoted for industrial iron precipitation. Large quantities of hazardous waste are generated in the removal process of iron in zinc hydrometallurgy, which poses a severely permanent threat to the environment. Recently, an innovative magnetite (Fe 3 O 4) method for iron precipitation has been proposed. Whereas, the magnetic separation performance and phase composition of Fe 3 O 4 are sensitively disturbed by the oxidizing conditions in the pregnant leach solution from zinc hydrometallurgy. In this work, a series of Fe 3 O 4 samples with different oxidation degrees were in-situ formed. We found that oxidation did not worsen the Fe removal and that all samples have a relatively high iron content (>42.3%). Meanwhile, although the magnetic properties of the samples showed a decrease (from 32.31 to 6.56 emu/g), it could be recovered (10.60 emu/g) by controlling the oxidation to a certain degree. This is correlated with the phase transition of iron oxides as the oxidation degree increase. Furthermore, it is clarified that the mechanism by which the oxidation affects the magnetic properties was the change of Fe-O bond length, as revealed by Raman and Fourier transform infrared spectrometer measurement. This work provides a new strategy for the practical implication of the "magnetic iron" instead of the magnetite precipitation method in zinc hydrometallurgy. [ABSTRACT FROM AUTHOR]

Recently, the mercury re-emission from the scrubbing solution has become a hot topic in wet flue gas desulfurization process (WFGD). Selenite is one of the most important matters in the solution. It is discovered that selenite have great effect on the mercury re-emission in the WFGD process in this paper. Several important parameters, such as selenite concentration, pH value, temperature and chloride concentration, and reaction mechanisms were studied on the Hg 0 re-emission. The experimental results indicate that mercury reduction and re-emission can be effectively inhibited with high selenite and chloride concentrations, low temperature and pH value. The mechanisms for inhibition of mercury reduction and re-emission are proved to be different under acid and alkaline conditions respectively. Under acid condition, it is the formation of stable HgSe that decrease Hg 0 re-emission. However, the formation of more stable HgSeO 3 SO 3 2 - or Hg ( SeO 3 ) 2 2 - than Hg ( SO 3 ) 2 2 - contributes to avoid the oxidized mercury reduction by sulfite ions and then the mercury re-emission under the alkaline condition. In addition, it is also found that Cl - ions can further enhance the inhibition effect and suppress Hg 0 re-emission by the formation of stable HgSeO 3 Cl - and HgSeO 3 Cl 2 2 - complexes. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in wastewater poses a severe threat to the environment and public health. Chemical precipitation is the most conventional process for heavy metal wastewater treatment. However, the flocculent structure of chemical precipitation sludge raises the problem of poor sludge settling performance that is difficult to overcome. Inspired by the biological granular sludge (BGS) formation process, we report here a facile and effective strategy to produce abiological granular sludge (ABGS) to solve this problem. In this procedure, controlled double-jet precipitation was performed to simulate the cell multiplication process in BGS formation by controlling the solution supersaturation. Meanwhile, ZnO seeds and flocculant polyacrylamide were added to simulate the role of nuclei growth and extracellular polymeric substances in BGS formation process, respectively. This procedure generates ABGS with a dense structure, large size and regular spherical morphology. The settling velocity of ABGS can reach up to 3.0cms−1, significantly higher than that of flocculent sludge (<1cms−1). [ABSTRACT FROM AUTHOR]

Comprehensive quantitative evaluation of the intercarotid artery distance (ICD) in the pediatric population has not been sufficiently explored. This study aims to measure the minimal ICDs at multiple levels of the skull base to assess changes in the ICD during development. Measurement of the ICDs between the paired paraclival, parasellar, and paraclinoid segments of the internal carotid artery (ICA) was performed on coronal MRI from 540 patients ranging from 0 to 17 years old (n = 30 for each age). Comparison of these indices in the very young (0–5 years, Group 1) and young (6–17 years, Group 2) patients, and assessment of the degree of sphenoid sinus pneumatization was employed. The narrowest ICD was located at the paraclinoid ICAs in the vast majority of cases (89.44%). When comparing the ICDs in very young age patients with the ICDs of 17 years old subjects, a statistically significant difference was found at the paraclival (ages 0–5), parasellar (ages 0–2), and paraclinoid (ages 0–4) ICDs (p < 0.05). Comparison of the ICDs between the intergroups (Group 1 and 2) also demonstrated a statistically significant difference (p < 0.0001). Pneumatization of the sphenoid sinus was initially noted to start at 3 years of age, and there were no patients with a non-pneumatized sphenoid sinus identified after 7 years of age in our cohort. Measurement of ICDs at multiple levels provides a valuable reference for EEA procedures in the pediatric population. While the ICD may be largely stable in the pediatric population after 5 years of age, additional anatomic factors may restrict transsphenoidal access in very young patients (0–5 years). [ABSTRACT FROM AUTHOR]