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In this work, the effect of non-drag forces (lift force, turbulent dispersion force, wall lubrication force and virtual mass force) and bubble induced turbulence (BIT) on the CFD-PBM simulation of ...

The Kolbe-Schmitt reaction is the traditional method for preparing 2,4- and 2,6- dihydroxybenzoic acid (2,4- and 2,6-DHBA). In this work, accurate kinetic models for the Kolbe-Schmitt synthesis of 2,4- and 2,6-DHBA were successfully developed. The relative errors between the theoretical and experimental 2,4-DHBA equilibrium yields are less than 3.7% as T = 348–473 K, [C6H6O2] = 0.4–0.8 M and [KHCO3] = 1.2–4.0 M. The effects of reaction temperature, reaction time, KHCO3 and resorcinol (C6H6O2) concentrations on the formation rates and the yields of 2,4- and 2,6-DHBA were investigated by the developed models. Results show that the 2,4-DHBA equilibrium yield exhibits a strong dependence on the KHCO3 concentration, and the formation rate of 2,4-DHBA is strongly dependent on the reaction temperature. Furthermore, the reaction time is a critical factor in controlling the ratio of 2,4-DHBA to 2,6-DHBA as the reaction temperature varies from 433 to 473 K. Additionally, the results of the present work deepen the understanding of the reaction mechanism, e.g. the rate-determining step and main reaction pathway of 2,6-DHBA formation.

The emergence of antibiotic resistant bacteria represents a significant and common clinical problem worldwide as infections are becoming increasingly common. It is urgent to broaden the sources of biomaterials that can prevent both bacterial infection and antibiotic resistance. In this work, oxidized sodium alginate/aminated hyaluronic acid (OSA/AHA) hydrogel with various proportions was developed based on Schiff base reaction. Herein, polydopamine (PDA)-Bmkn2 nanoparticle and sanguinarine were incorporated into hydrogels to enhance antibacterial properties. The prepared PDA-Bmkn2 nanoparticles, with uniform particle size and good dispersion, could serve as a delivery system for Bmkn2. The prepared hydrogels showed appropriate swelling ratio, extremely good mechanical strengths and improved biodegradability. Meanwhile, the Bmkn2 and sanguinarine were released from the hydrogels in a sustainable manner. Furthermore, OSA/AHA/sanguinarine/PDA-Bmkn2 hydrogel (less than 10 μg/mL BmKn2 and 0.2 μg/mL sanguinarine) had excellent biocompatibility. Antibacterial experiments confirmed that OSA/AHA/sanguinarine/PDA-Bmkn2 hydrogel had effective antimicrobial activity on Escherichia coli and Staphylococcus aureus. Therefore, the prepared injectable hydrogels with good biocompatibility and excellent synergistic antibacterial activity promise great potential for preventing localized bacterial infections.

Knowledge of the heat transfer coefficients in bubble columns can offer valuable references for the design and scale-up of reactors. This work aims to develop reliable correlations that can be applied in precisely predicting the global and local heat transfer coefficients in air-water or air-water-glass beads bubble columns. The influence of superficial gas velocities, column dimensions, volume fraction of particles, internals and radial positions on the heat transfer coefficients is considered in the developed correlations. In addition, the effect of the function forms on the accuracy of calculated local heat transfer coefficients is investigated. The Levenberg-Marquardt Algorithm is used to determine the values of the parameters in the empirical correlations. The recommended correlations can be applied in accurately predicting the heat transfer coefficients in bubble columns.

This work investigates the effects of coalescence and breakup models on the radial distribution of gas holdup and local bubble size distribution in a laboratory scale bubble column operated at 0.11 m/s, 0.14 m/s, 0.19 m/s and 0.23 m/s. The results quantitatively show the influences of bubble coalescence due to various mechanisms, coalescence efficiency calculated by different models, modification coefficients for coalescence rates, critical energy required for breakup and bubble breakage caused by large scale eddies and viscous shear on numerical simulations. Furthermore, qualitative analysis is performed to analyze the effects of these factors. The performance of various models is evaluated (e.g. Han’s breakup model and Das’s coalescence model). Some optimized combinations of coalescence and breakup models that can be used to accurately predict the local gas holdup and bubble size distribution in laboratory scale bubble columns operated at heterogeneous regime are proposed.

The class method (CM) has been frequently applied in solving population balance equations (PBEs) for the CFD-PBM simulation of bubble columns. There are four parameters in the CM: the volume ratio between successive bubble classes (rv), the minimum diameter (dmin), the maximum diameter (dmax) and the critical diameter (dc) that is used to distinguish small bubbles and large bubbles. These parameters have a significant impact on the computational precision and efficiency. In this work, numerical simulations are performed to investigate the effects of these parameters on the simulation of two typical bubble columns operated at heterogeneous regime. The simulation results quantitatively present the influences of these parameters on the simulated local gas holdup and global bubble size distribution. The simulated radial profiles of gas holdup at different heights are compared with experimental data. The optimized scheme for the values of these parameters in the CM is proposed.

Background Disabled homolog 2-interacting protein (DAB2IP), a Ras GTPase-activating protein, is downregulated in several cancers. Its depletion is involved in tumor cell proliferation, apoptosis, and metastasis, as well as epithelial-mesenchymal transition. The present study aimed to explore the potential role of DAB2IP in cutaneous squamous cell carcinoma (cSCC) and provide a theoretical basis for the diagnosis and targeted therapy of cSCC. Methods The clinicopathological features of DAB2IP expression in cSCC were analyzed by immunohistochemistry, and the effects of DAB2IP on SCL-1 cell behavior were determined via genetic interference in vitro. SCL-1 cell lines that exhibited reduced expression of DAB2IP and a scrambled shRNA control were constructed using a lentivirus vector-based shRNA technique. RNA extraction, reverse transcription-quantitative PCR (RT-qPCR), MTT assay, colony formation test, cell cycle analysis, apoptosis test, transwell assay, wound-healing assay, in vitro invasive assay were used in this study. Results The immunohistochemical results demonstrated that the expression of DAB2IP was higher in cSCC tissues than in soft fibroma. The level of DAB2IP expression was associated with the degree of malignancy and the depth of tumor infiltration; however, it had no association with patients' sex, tumor size, location, or phenotype. The results of the MTT, cell cycle, apoptosis, and invasion experiments demonstrated that knockdown of DAB2IP inhibited the viability and invasion of SCL-1 cells in vitro. Conclusions High expression of DAB2IP may contribute to the development and proliferation of cSCC.

In this study, a bi-salt sorbent was observed to exhibit better adaptability to the heating and cooling temperatures than conventional single-salt sorbents. A reactor filled with the bi-salt sorbent of CaCl2 and MnCl2 was designed, and the performance for long-term thermal energy storage, which included several months of seasonal energy storage and a few days of exhaust gas heat storage in winter, was analyzed. The thermal energy charging rate under both working conditions increased with the heating temperature; however, the COPh exhibited a downward trend. The COPh of seasonal energy storage was maintained above 0.5, and the COPh of exhaust gas heat storage was slightly higher at approximately 0.7. For both working conditions, the average heat-producing power in 50 min increased to approximately 9 kW, and the energy-storage density increased to approximately 1900 kJ∙kg−1, which was approximately 100% higher than that of existing resorption systems with single-salt sorbents.

Background Autosomal recessive congenital ichthyosis (ARCI) is a group of genetically heterogeneous diseases. Mutations in transglutaminase (TGase) 1 gene (TGM1, OMIM 190195) have been implicated in ARCI. However, little is known about TGM1 mutations in the Chinese population, and no functional studies have investigated the biological effect of mutant TGM1 on human epidermal keratinocytes (HaCaT) cells. Objectives To identify the pathogenic mutations of TGM1 gene in two Chinese siblings with ARCI and gain insight into functional consequences of these mutations. Methods Fifteen exons and flanking splice sites of TGM1 gene were amplified by polymerase chain reaction and then underwent bidirectional Sanger sequencing. The HaCaT cells were transfected with lentiviral vectors, which overexpressed either wild-type or mutant TGM1 cDNAs with deleted homeodomain. Cell proliferation and cell cycle progression were detected. The expression of cyclin D1, cyclin B1, CDK4, TGM1, K10, involucrin, and filaggrin proteins were investigated by Western blot analysis. Results We found two compound heterozygous missense mutations (c.515C>T, R143C in exon 3 and c.759C>T, S212F in exon 4) in both siblings. HaCaT cells transfected with mutant TGM1 cDNAs displayed a lower growth rate and delayed S phase while overexpression of wild-type TGM1 cDNAs led to accelerated growth. HaCaT cells transfected with mutant TGM1 cDNAs displayed lower expression of differentiation markers such as involucrin and filaggrin. Our findings suggest that the compound heterozygous missense (c.515C>T, R143C) mutations in exon 3 and missense (c.759C>T, S212F) mutations in exon 4 result in the phenotype of ARCI. TGM1 mutations can suppress keratinocyte growth and cornified cell envelope formation.

The three-dimensional (3-D) flow structures in the Taiziji Waterway of the Lower Yangtze River were simulated by a 3-D numerical model, where the river plan form is a sharp bend and island-braided. The verification results of the 3-D model indicated that the simulated results agree with the measured data. The patterns of 3-D flow structures in this sharp bend with different discharge were analyzed based on the calculated results.The simulated results demostrated that strong 3-D features of flow structures can be found in the sharp bend of Taiziji Waterway, the bottom velocity vectors point to the convex bank while the surface vectors point to the concave bank. The velocity distribution alone the lateral direction in the sharp bend depends mostly on the flow discharge. The discharge ratio of the left branch increases as flow discharge increases.

A total of 1224 Neisseria gonorrhoeae isolates from Guangzhou in 2 periods (2000-2005 and 2008-2013) were subjected to antimicrobial susceptibility testing. The percentage of penicillin- and ciprofloxacin-resistant isolates increased from 71.1% (473/665) to 90.9% (508/559) and 88.9% (591/665) to 98.0% (548/559), respectively. All isolates remain susceptible to spectinomycin and ceftriaxone, with increasing minimum inhibitory concentrations.

The velocity distribution and bed deformation patterns in a meandering channel with consecutive bends were investigated by using both an experimental study and a 3-D flow and sediment transport model. The simulated results from the 3-D model agree well with the experimental data. The flow structure and bed deformation patterns in channel bends with different flow conditions were analyzed. Modeled results demonstrated that the velocity distribution and bed deformation in the meandering channel depend mostly on the flow regimes. For the case of small flow discharge, the maximum velocity occurs in the vicinity of concave bank. For the case of large discharge, the maximum velocity occurs near the center part of the channel. Consequently, bed deformation patterns in meandering channels will be influenced by the flow conditions.

Figure S2. A neighbor-joining phylogenetic tree was constructed using the concatenated sequences of por (490 bp) and tbpB (390 bp) alleles, which were identified by the NG-MAST method, from 44 AZM-MLR N. gonorrhoeae isolates in Guangzhou, China in 2009â 2013. (DOCX 1372Â kb)

Figure S1. A neighbor-joining phylogenetic tree was constructed using the concatenated sequences of por (490 bp) and tbpB (390 bp) alleles, which were identified by the NG-MAST method, from 33 AZM-LLR N. gonorrhoeae isolates in Guangzhou, China in 2009â 2013. (DOCX 1475Â kb)

Table S1. Characteristics of AZM-LLR N. gonorrhoeae isolates identified in Guangzhou in 2009-2013 (n = 33). Table S2. Characteristics of AZM-MLR N. gonorrhoeae isolates identified in Guangzhou in 2009-2013 (n = 44). Table S3. The classification of mutation patterns of the PBP2 proteins based on amino acids 500 to 570. (DOCX 46.2 kb)

Dyskeratosis follicularis (Darier’s disease, DD) is rare autosomal dominant disease characterized by hyperkeratotic papules that coalesce into plaques and occur primarily in seborrheic or intertriginous areas. Associated findings include nail abnormalities. A 3-year-old boy presented with porcupine-like appearance for 2 years. The lesion from the back was taken for light microscopy and electron microscopy. He was treated with acitretin (0.31 mg/d to 0.66 mg/d) for 8 years. Light microscopy and electron microscopy showed that the typical features of DD. The patient show good respond to the treatment. During 8 years treatment, the patient had dry mouth and pruritus. The skeletal abnormalities didn’t happen in the patient. The serum lipid profile, liver function and renal function within normal lever after treatment. Our findings showed that porcupine-like appearance is a unique pattern of DD. Acitretin may be a useful therapeutic agent in children with DD and less likely to cause skeletal problems.

Underground excavation will influence the safety of the geotechnical surroundings. Based on the stochastic medium theory, influence on the surrounding rock and soil by underground excavation is studied. Formula for predicting movement and deformation of rock and soil mass caused by excavation are deduced, and especially for those with horizontal rectangle section, semi-analytic solution for this problem is put forward. Furthermore, a computer program is developed to compute the movement and deformation of the rock and soil mass resulted from excavation. The theory is applied in an engineering example, which shows that the results of the research are reasonable and the developed solutions can be used for safety evaluation of underground excavations.

To detect potential mutations of gap junction protein beta 2 (GJB2) and loricrin (LOR) genes in two patients with Vohwinkel syndrome.Polymerase chain reaction and DNA sequencing were used for detecting potential mutations in the GJB2 and LOR genes. Parents of one patient and 50 healthy individuals were used as controls.A novel homozygous missense mutation (c.A796G) of LOR gene was detected in one patient. The same mutation was not found in the other patient, their relatives and the 50 healthy controls.A missence mutation of LOR gene was detected in a patient with Vohwinkel syndrome.

To investigate the association of filaggrin gene (FLG) polymorphism with atopic dermatitis (AD) in southern Chinese Han population.The frequencies of the 13 known FLG gene single nucleotide polymorphism(SNPs), including 3321delA, 441delA, 1249insG, E1795X, S3296X, R501X, 2282del4, R2447X, S2889X, 7945delA, 3702delG, Q2417X, R4307X, were detected in a cohort of 50 AD patients and 100 control individuals using polymerase chain reaction (PCR) and DNA sequencing.FLG 3321delA and 441delA were detected in 14 (28%) and 6 (12%) AD patients, respectively. The other 11 SNPs were not detected in the patients. None of the 13 SNPs was detected in the controls.The results suggested that the FLG gene might be associated with atopic dermatitis susceptibility in southern Chinese Han population.