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An incomplete Freund’s adjuvant elicited an overt pathogenesis in vaccinated mice following the intranasal challenge of A/California/07/2009 (H1N1) virus despite the induction of a higher specific antibody titer than other adjuvanted formulations. Aluminum hydroxide adjuvants have not induced any pathogenic signs in a variety of formulations with glycolipids. A glycolipid, α-galactosyl ceramide, improved a stimulatory effect of distinct adjuvanted formulations on an anti-influenza A antibody response. In contrast to α-galactosyl ceramide, its synthetic analogue C34 was antagonistic toward a stimulatory effect of an aluminum hydroxide adjuvant on a specific antibody response. The aluminum hydroxide adjuvant alone could confer complete vaccine-induced protection against mortality as well as morbidity caused by a lethal challenge of the same strain of an influenza A virus. The research results indicated that adjuvants could reshape immune responses either to improve vaccine-induced immunity or to provoke an unexpected pathogenic consequence. On the basis of these observations, this research connotes the prominence to develop a precision adjuvant for innocuous vaccination aimed at generating a protective immunity without aberrant responses.

Klebsiella pneumoniae is an important pathogen associated with nosocomial infection and has developed increasing resistance to antibiotics such as extended-spectrum β-lactams and carbapenem. In recent years, K. pneumoniae isolates have emerged as a major cause of global community-acquired infections such as pneumonia and pyogenic liver abscess. Although serotypes K1 and K2 have been identified as the predominant capsular types associated with invasive infections, no K. pneumoniae vaccine is commercially available, probably due to immunogenicity loss in the traditional depolymerization method to obtain capsule polysaccharide (CPS) for the preparation of conjugated vaccine. In this study, we successfully retained immunogenicity by using K1 (K1-ORF34) and K2 (K2-ORF16) CPS depolymerases that were identified from phages to cleave K1 and K2 CPSs into intact structural units of oligosaccharides with intact modifications. The obtained K1 and K2 oligosaccharides were separately conjugated with CRM197 carrier protein to generate CPS-conjugated vaccines. Immunization experiments of mice showed both K1 and K2 CPS-conjugated vaccines induced anti-CPS antibodies with 128-fold and 64-fold increases of bactericidal activities, respectively, compare to mice without vaccinations. Challenge tests indicated that K1 or K2 CPS-conjugated vaccine and divalent vaccine (a mixture of K1 and K2 CPS-conjugated vaccines) protected mice from subsequent infection of K. pneumoniae by the respective capsular type. Thus, we demonstrated K1 and K2 CPS-conjugated vaccines prepared by CPS depolymerases is a promising candidate for developing vaccines against human K. pneumoniae infections.

Safety is a critical concern in underground mining. Operations should be designed according to a vision of zero accident and fatality. A refuge chamber is a station where worker lives are maintained throughout an emergency until they are saved. Given that workers perform their duties in different areas of underground, the number of refuge chambers and their locations are of paramount importance as workers must be able to access them rapidly. Furthermore, the task of refuge chamber localization needs to consider the fact that the number of workers in a different area and the structural characteristics and stability conditions of these areas will not be identical. This paper aims to determine the optimal locations of the refuge chambers in the underground network considered as a tree. Initially, a formula quantifying the importance of each worksite is developed. Then, two main strategies are presented as feasible localization solutions: A recursive solution to the 'Absolute Weighted P-centre Problem' and a spiral approach to the 'Total Covering problem'. The functionalities of the proposed approaches are demonstrated by case studies. Results show that the proposed methods can find viable locations for refuge chambers while fulfilling varied maximum safety distances of each working area. [ABSTRACT FROM AUTHOR]

In this work, we employ the two-fluid model under the large eddy simulations (LES) framework to investigate liquid–liquid dispersions in stirred tanks. The population balance equation was solved by the one primary and one secondary particle method, which was proven as identical as one-node quadrature method of moments. First, Aiyer's break-age kernel was investigated for its capability in the context of chemical stirred tank applications [Aiyer et al., "A population balance model for large eddy simulation of polydisperse droplet evolution," J. Fluid Mech. 878, 700–739 (2019)]. Second, two new methods were proposed to handle the consistency problem and boundedness problem. These numerical problems were shown in our previous studies but had never been discussed in detail. Three test cases were launched, and results showed that our implementation ensures the moments' boundedness. The inconsistency problem was also treated properly. The predicted diameter also agrees well with experiments. Meanwhile, the phase segregation problem as observed in the unsteady Reynolds-Averaged Navier–Stokes simulations disappeared when a LES turbulence model was employed. [ABSTRACT FROM AUTHOR]

With the evolution of the Internet and the introduction of third-party platforms, a diversified supply chain has gradually emerged. In contrast to the traditional single sales channel, companies can also increase their revenue by selling through multiple channels, such as dual-channel sales: adding a sales channel for direct sales through online third-party platforms. However, due to the complexity of the supply chain structure, previous studies have rarely discussed and analyzed the capital-constrained dual-channel supply chain model, which is more relevant to the actual situation. To solve more complex and realistic supply chain decision problems, this paper uses the concept of game theory to describe the pricing negotiation procedures among the capital-constrained manufacturers and other parties in the dual-channel supply chain by applying the Stackelberg game theory to describe the supply chain structure as a hierarchical multi-level mathematical model to solve the optimal pricing strategy for different financing options to achieve the common benefit of the supply chain. In this study, we propose a Multi-level Improved Simplified Swarm Optimization (MLiSSO) method, which uses the improved, simplified swarm optimization (iSSO) for the Multi-level Programming Problem (MLPP). It is applied to this pricing strategy model of the supply chain and experiments with three related MLPPs in the past studies to verify the effectiveness of the method. The results show that the MLiSSO algorithm is effective, qualitative, and stable and can be used to solve the pricing strategy problem for supply chain models; furthermore, the algorithm can also be applied to other MLPPs. [ABSTRACT FROM AUTHOR]

Adolescents with comparable personal risk factors may have different lipid profiles because of the school's context. Lipid determinants in adolescents should be considered using a multilevel perspective. This multilevel study investigated the effects of individual-level and school-level factors on lipid profiles in adolescents and evaluated the cross-level influence of lipid determinants. A representative adolescent cohort (n = 2727) was randomly selected from 36 schools in three diverse economic areas in Taiwan and assessed for their personal dietary patterns, physical parameters, and lipid profiles. For individual-level factors, both low physical activity and high body mass index (BMI) were associated with elevated triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) levels, and a sugar-sweetened beverage intake of >500 mL/day was associated with increases of 5.97 and 6.12 mg/dL in LDL-C and TC levels, respectively, compared with abstinence. Regarding school-level factors, students in schools with ≥2 health promotion programs per year had a 5.27 mg/dL lower level of LDL-C than those in schools with 0–1 program, and students in schools with ≥46 food outlets within 600 m of the school had 6.90 and 13.3 mg/dL higher levels of TG and TC, respectively, than those in schools with <46 food outlets. School context modified the individual-level positive correlation between BMI and TG level (the p-value for the random-slope effect was 0.003). In conclusion, individual-level and school-level factors exert a multilevel effect on adolescent lipid profiles. The food environment near the school has a stronger cross-level impact on individual TG levels in adolescents with a high BMI than in those with a normal BMI. [ABSTRACT FROM AUTHOR]

BACKGROUND The rotating foam stirrer reactor (RFSR) has shown its high mass transfer efficiency. Nevertheless, its micromixing efficiency, which is one of the significant parameters, still needs more comprehensive study for its better application and optimization. This work therefore employed the iodide–iodate reaction system to analyze the micromixing efficiency in an RFSR, and the effects of reactor configuration and liquid viscosity on micromixing efficiency were investigated. RESULTS: The results show that high micromixing efficiency can be achieved when the feed location is at the outer edge of the rotor. Solid foam with low pores per linear inch (ppi) and equipping baffles on the reactor wall can also considerably improve the micromixing efficiency. The results further reveal that the micromixing efficiency decreased with increasing liquid viscosity. Micromixing times in an RFSR with various configurations, estimated based on the incorporation model, ranged from 2.1 × 10−4 to 2.0 × 10−2 s. The minimum value is smaller than that of many conventional reactors and is competitive with that of some novel reactors. In addition, a correlation to predict the micromixing time based on the average energy dissipation rate was developed, which agreed well with experimental values. CONCLUSION: This study indicates that the RFSR has excellent micromixing efficiency and also provides fundamental information for optimization of the RFSR and its application in process industries. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A rotating foam reactor (RFR), which comprises a solid foam block stirrer as opposed to the agitator blade in stirred tanks, has recently received a significant amount of research interest due to its high mass transfer rates. For a deeper insight into the RFR the work herein investigated the micromixing efficiency of the RFR in terms of segregation index (Xs) using the iodide‐iodate reaction system. The effects of various operating parameters including injection time, rotational speed, acid concentration, volume of liquid, volumetric ratio, and gas flow rate on segregation index were systematically examined. Results showed that the segregation index remained constant when injection time exceeded 100 s. Moreover, the Xs increased with an increase in acid concentration but decreased with an increase in rotational speed, volume of liquid, volumetric ratio, and gas flow rate. Micromixing time was also calculated based on the incorporation model and was established to range from 1.1 × 10−3–4.5 × 10−2 s, which is much shorter than that of conventional reactors. The results herein demonstrate that an RFR exhibits excellent micromixing efficiency and has a significant potential for use in chemical industries. [ABSTRACT FROM AUTHOR]

A rotating packed bed (RPB) is one of the cutting‐edge process intensification technologies due to its high mass transfer and mixing efficiency. Nevertheless, owing to the complex structure and hydrodynamic characteristics of RPBs, valuable data inside the reactor is hard to obtain by conventional experimental methods. Computational fluid dynamics (CFD) owing to its unique advantages of low cost, completeness of data and ability to simulate real and ideal conditions, has been adopted by many researchers to carry out fundamental research and practical application of RPBs in recent years. This paper therefore elaborates on the research progress on CFD simulation of RPBs. The building of a physical model of these reactors as well as selection of mathematical models are described, then applicability and accuracy of these models are compared and discussed. Simulation results for gas and multiphase flow in reactors are also presented. Additionally, the application of CFD to mixing and mass transfer between phases and processes in rotating packed beds is introduced. Optimum designs of reactors by the CFD method are also described. Finally, problems remaining with CFD simulation of rotating packed beds and future development directions are discussed. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Carbohydrate-based vaccines have shown therapeutic efficacy for infectious disease and cancer. The mushroom Ganoderma lucidum (Reishi) containing complex polysaccharides has been used as antitumor supplement, but the mechanism of immune response has rarely been studied. Here, we show that the mice immunized with a L-fucose (Fuc)-enriched Reishi polysaccharide fraction (designated as FMS) induce antibodies against murine Lewis lung carcinoma cells, with increased antibody-mediated cytotoxicity and reduced production of tumor-associated inflammatory mediators (in particular, monocyte chemoattractant protein-1). The mice showed a significant increase in the peritoneal B1 B-cell population, suggesting FMS-mediated anti-glycan IgM production. Furthermore, the glycan microarray analysis of FMS-induced antisera displayed a high specificity toward tumor-associated glycans, with the antigenic structure located in the nonreducing termini (i.e., Fucα1-2Galβ1-3GalNAc-R, where Gal, GalNAc, and R represent, respectively, D-galactose, D-N-acetyl galactosamine, and reducing end), typically found in Globo H and related tumor antigens. The composition of FMS contains mainly the backbone of 1,4-mannan and 1,6-α-galactan and through the Fucα1-2Gal, Fucα1-3/4Man, Fucα1-4Xyl, and Fuca1-2Fuc linkages (where Man and Xyl represent D-mannose and D-xylose, respectively), underlying the molecular basis of the FMS-induced IgM antibodies against tumor-specific glycans. [ABSTRACT FROM AUTHOR]

Tin disulfide has substantial importance for two-dimensional material-based optoelectronics and sensors due to its unique optoelectrical properties. In this report, we fabricate SnS2 nanosheets using the low-pressure thermal sulfurization process, whose crystal structure and surface morphology are confirmed by X-ray diffraction (XRD) and scanning electron microscope (SEM) measurements. From photoconductivity measurement and photocurrent mapping, we observe smaller electrode spacing of SnS2 thin films can enhance photodetection. Then, by the H2O2 oxidation processing, we transform SnS2 to SnO2 to detect humidity. The measured response and recovery time can be optimized to 5.6 and 1.0 s, respectively, shorter than those of commercial DHT11 humidity sensor of 32 and 34 s. At suitable bias, humidity sensor can detect human respiration properly at room temperature. Our results show that SnS2 nanosheets exhibit reasonable performance for emergent photodetector applications and humidity sensing. [ABSTRACT FROM AUTHOR]

In this study, a tin-based oxide (SnOx) semiconductor layer on a commercial indium tin oxide (ITO)/glass substrate was investigated for the first time for use as the active layer of a light-addressable potentiometric sensor (LAPS). The photoabsorption of SnOx layers sputtered using varying Ar/O 2 gas flow ratios was characterized by means of the ultraviolet–visible spectroscopy (UV–Vis); the photo/electric response of a LAPS directly covered with an NbOx sensing membrane was evaluated under modulated ultraviolet illumination. In situ substrate heating at 250 °C during sputtering and post-deposition rapid thermal annealing (RTA) with temperatures of 400 and 450 °C in a N 2 environment were applied to study sample behavior. Based on X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results, the fabricated SnO 2 layer can be transformed into a polycrystalline SnO 2 phase in the bulk with a surface SnO layer by thermal budget. A high photocurrent and an acceptable pH sensitivity of 1.29 μA and 57.6 mV/pH, respectively, are obtained under UV light-emitting diode (LED) illumination for a LAPS built using a SnOx layer sputtered with a flow ratio of Ar/O 2 = 46/4 with substrate heating at 250 °C. The stability and lifetime performance of the SnOx LAPS needs to be improved by further process optimization, especially in terms of developing a crack-free SnOx process and increasing sensing membrane coverage. The experimental results show the potential of SnOx for use as the active layer in a LAPS. • A SnOx semiconductor layer is firstly investigated for light‐addressable potentiometric sensor (LAPS). • A SnOx layer sputtered with flow ratio of Ar/O2 = 46/4 with substrate heating at 250 °C is the current optimized condition. • The photocurrent is 1.29 μA under the UV LED illumination with 1 kHz. • An acceptable pH sensitivity of 57.6 mV/pH is obtained with a NbOx sensing membrane. [ABSTRACT FROM AUTHOR]