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The contents of alkali and alkaline earth metals are higher in Zhundong coal, and there are serious problems of slagging and fouling during the combustion process. Therefore, it is of great significance to reveal the mechanism of slagging and fouling in the boiler of Zhundong coal. In this paper, first-principle calculations based on density functional theory are used to study the competition mechanism of alkaline metal oxides during the combustion process in Zhundong coal by establishing the Na2O(110)/CaO(100)-SiO2(100) double-layer interface model. The results show that the bond lengths of the surface of Na2O(110) and CaO(100) with SiO2(100) after adsorption were generally lengthened and the value of bond population became smaller, which formed a stable binding energy during the reaction. The electron loss of Na is 0.05 e, the electron loss of Ca is 0.03 e, and the electron loss of Na2O is greater than that of CaO. The charge transfer on the surface of Na2O with SiO2 is obviously higher than that of CaO and the orbital hybridization on the surface of CaO with SiO2 is weaker than that on the surfaces of Na2O with SiO2. Na2O is easier to react with SiO2 than CaO. The adsorption energies on the surface of Na2O and CaO with SiO2 are −5.56 eV and −0.72 eV, respectively. The adsorption energy of Na2O is higher than that of CaO, indicating that Na2O is more prone to adsorption reactions and formation of Na-containing minerals and other minerals, resulting in more serious slagging. In addition, the XRD analyses at different temperatures showed that Na-containing compounds appeared before Ca-containing ones, and the reaction activity of Na2O is stronger than that of CaO in the reaction process. The experimental results have good agreement with the calculation results. This provides strong evidence to reveal the slagging and fouling of Zhundong coal. [ABSTRACT FROM AUTHOR]

This article discusses the establishment of a novel severe asthma canine model for research on respiratory intervention therapies. The researchers aimed to create a large animal model of asthma that closely mimics the clinical signs and features of severe asthma in humans. They exposed adult beagles to Toluene diisocyanate (TDI) via aerosol inhalation and observed pronounced asthma clinical signs, airway inflammation, and remodeling. The model also demonstrated the efficacy of respiratory intervention therapy. This model provides a valuable tool for studying the mechanisms and effectiveness of interventional pulmonological therapies for severe asthma. [Extracted from the article]

This research investigates growth inhibitors for smart services driven by condition‐based maintenance (CBM). Despite the fast rise of Industry 4.0 technologies, such as smart sensoring, internet of things, and machine learning (ML), smart services have failed to keep pace. Combined, these technologies enable CBM to achieve the lean goal of high reliability and low waste for industrial equipment. Equipment located at customers throughout the world can be monitored and maintained by manufacturers and service providers, but so far industry uptake has been slow. The contributions of this study are twofold. First, it uncovers industry settings that impede the use of equipment failure data needed to train ML algorithms to predict failures and use these predictions to trigger maintenance. These empirical settings, drawn from four global machine equipment manufacturers, include either under‐ or over‐maintenance (i.e., either too much or too little periodic maintenance). Second, formal analysis of a system dynamics model based on these empirical settings reveals a sweet spot of industry settings in which such inhibitors are absent. Companies that fall outside this sweet spot need to follow specific transition paths to reach it. This research discusses these paths, from both a research and practice perspective. Highlights: Condition‐based maintenance (CBM)‐driven smart services have become technically much more feasible and affordable through the fast rise of Industry 4.0 technologies, such as smart sensoring, internet of things, and machine learning (ML), and yet such smart services have failed to keep pace with this rise.A key CBM‐specific complication for service growth is that, in order to reach high‐quality performance of such smart services, the ML‐algorithms that drive them need significant numbers of equipment failures to learn from.Such failure data may be hard to obtain for OEMs, either because certain components fail to often (and hence are replaced, making the failure data obsolete) or too rarely (making the time needed to collect failure data very long).Also, customers may be very much reliability focused (leading to much preventive maintenance and so few failures) or not sufficiently reliability focused (leading to much unmonitored corrective maintenance and low interest in advanced services such as CBM).The sweet spot for CBM smart services therefore lies somewhere in the middle, with both a fair amount of component failures and fairly strongly reliability‐oriented customers. [ABSTRACT FROM AUTHOR]

IGHV polymorphism provides a rich source of humoral immune system diversity. One important example is the IGHV1-69 germline gene where the biased use of alleles that encode the critical CDR-H2 Phe54 (F-alleles) to make broadly neutralizing antibodies (HV1-69-sBnAb) to the influenza A hemagglutinin stem domain has been clearly established. However, whether IGHV1-69 polymorphism can also modulate B cell function and Ab repertoire expression through promoter and copy number (CN) variations has not been reported, nor has whether IGHV1-69 allelic distribution is impacted by ethnicity. Here we studied a cohort of NIH H5N1 vaccinees and demonstrate for the first time the influence of IGHV1-69 polymorphism on V-segment usage, somatic hypermutation and B cell expansion that elucidates the dominance of F-alleles in HV1-69-sBnAbs. We provide evidence that Phe54/Leu54 (F/L) polymorphism correlates with shifted repertoire usage of other IGHV germline genes. In addition, we analyzed ethnically diverse individuals within the 1000 genomes project and discovered marked variations in F- and L- genotypes and CN among the various ethnic groups that may impact HV1-69-sBnAb responses. These results have immediate implications for understanding HV1-69-sBnAb responses at the individual and population level and for the design and implementation of universal influenza vaccine.

Background and aims: Post-tuberculosis bronchial stenosis (PTBS) is one of the most common complications of tracheobronchial tuberculosis. Silicone stent serves as a major treatment for maintaining airway patency. However, silicone stent placement remains a large challenge in patients with severe cicatricial PTBS. Our objective was to evaluate the efficacy and safety of covered, self-expanding, metallic stents (SEMSs) as a transition to silicone stent implantation for treating severe PTBS. Methods: We retrospectively reviewed the data of patients with severe PTBS who received airway stenting in the First Affiliated Hospital of Guangdong Medical University between September 2015 and May 2019. The types of the stent, intervention procedures, bronchoscopic findings, clinical outcomes and related complications were collected and analyzed. Results: Fifty-eight cases with severe PTBS were included in this study. Thirteen (22.4%) of the patients received bronchial silicone stent implantation immediately after dilations. For the remaining 45 (77.6%) patients, silicone stents could not be deployed after dilations and SEMSs implantation was implemented as a bridge to silicone stenting. The SEMSs were placed for an interval of 28.4 ± 11.1 days. All of the silicone stents were inserted successfully following the removal of SEMSs. No SEMS-related complication occurred. The subgroup analysis showed that patients who received transitional SEMSs had less luminal caliber but fewer transbronchial dilations before silicone stent implantation ( p

Recent studies have shown high usage of the IGHV1-69 germline immunoglobulin gene for influenza hemagglutinin stem-directed broadly-neutralizing antibodies (HV1-69-sBnAbs). Here we show that a major structural solution for these HV1-69-sBnAbs is achieved through a critical triad comprising two CDR-H2 loop anchor residues (a hydrophobic residue at position 53 (Ile or Met) and Phe54), and CDR-H3-Tyr at positions 98±1; together with distinctive V-segment CDR amino acid substitutions that occur in positions sparse in AID/polymerase-η recognition motifs. A semi-synthetic IGHV1-69 phage-display library screen designed to investigate AID/polη restrictions resulted in the isolation of HV1-69-sBnAbs that featured a distinctive Ile52Ser mutation in the CDR-H2 loop, a universal CDR-H3 Tyr at position 98 or 99, and required as little as two additional substitutions for heterosubtypic neutralizing activity. The functional importance of the Ile52Ser mutation was confirmed by mutagenesis and by BCR studies. Structural modeling suggests that substitution of a small amino acid at position 52 (or 52a) facilitates the insertion of CDR-H2 Phe54 and CDR-H3-Tyr into adjacent pockets on the stem. These results support the concept that activation and expansion of a defined subset of IGHV1-69-encoded B cells to produce potent HV1-69-sBnAbs does not necessarily require a heavily diversified V-segment acquired through recycling/reentry into the germinal center; rather, the incorporation of distinctive amino acid substitutions by Phase 2 long-patch error-prone repair of AID-induced mutations or by random non-AID SHM events may be sufficient. We propose that these routes of B cell maturation should be further investigated and exploited as a pathway for HV1-69-sBnAb elicitation by vaccination.

The content of alkaline earth metals in Zhundong (ZD) coal ash has a great effect on its melting characteristics. Herein, the influence of MgO content on a silicate microstructure was studied using molecular dynamics simulation under the conditions of 40 mol% high calcium and 20 mol% low calcium. Moreover, the theoretical results were verified by the Fourier transform infrared (FTIR) spectroscopy analysis of synthetic coal ash. In the MgO–CaO–Al2O3–SiO2 system, the results showed that the average bond lengths of Si–O and Al–O in the system are 1.61 and 1.75 Å, respectively, under the high calcium condition. With an increase in MgO content, Q4 with a high degree of polymerization was depolymerized and changed into Q1, Q2 and Q3 with a low degree of polymerization; Ot decreased, Ob increased first and then decreased, and Onb increased. Under the low calcium condition, the average bond lengths of Si–O and Al–O were 1.61 and 1.76 Å, respectively. When the content of MgO increased, Q4 was depolymerized into Q2 and Q3, Ot decreased, Onb increased, and Ob only increased by 1%. Compared with Si4+, Mg2+ easily attacks Al3+, and the degree of damage to the [AlO4]5− tetrahedron is greater. By comparing the distribution of oxygen and the degree of polymerization in the high calcium and low calcium systems, it was concluded that MgO more easily destroys the silicate networks of ash under the condition of high calcium CaO content of 40 mol%, which changes the viscosity and combustion characteristics of the system. [ABSTRACT FROM AUTHOR]

Background: Ewing sarcoma is a rare tumor of the bone or soft tissues characterized by diffuse membranous staining for CD99. As this tumor remains incurable in the metastatic, relapsed, and refractory settings, we explored the downstream immune implications of targeting CD99. Methods: We discovered a human anti-CD99 antibody (NOA2) by phagemid panning and investigated NOA2 immune cell-mediated cytotoxicity in vitro and in vivo focusing on the myeloid cell compartment, given that M2 macrophages are present in human tumors and associated with a poor prognosis. Results: NOA2 is capable of inducing immune effector cell-mediated Ewing death in vitro via engagement of macrophages. Mice with metastatic Ewing tumors, treated with NOA2, experience tumor growth arrest and an associated increase in intratumoral macrophages. Further, incubation of macrophages and Ewing cells with NOA2, in conjunction with anti-PILRα antibody blockade in vitro, results in the reactivation of previously dormant macrophages possibly due to interrupted binding of Ewing CD99 to macrophage PILRα. Conclusions: These studies are the first to demonstrate the role of human immune effector cells in anti-CD99-mediated Ewing tumor death. We propose that the engagement of CD99 by NOA2 results in the recruitment of intratumoral macrophages. In addition, interruption of the CD99:PILRα checkpoint axis may be a relevant therapeutic approach to activate tumor-associated macrophages. [ABSTRACT FROM AUTHOR]