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Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the operation progress of solid oxide fuel cell (SOFC), the performance and endurance are two major concerns significantly affected by gas flowing, charge transport, and chemical reaction. This paper presents a thorough research on the key parameters related to syngas and charge transport in the SOFC to reveal the intrinsic influence mechanism, including electro conductibility, gas mixture concentration, CH4 component ratio, temperature, and anode thickness, which is instrumental in improving the operational efficiency and applicability of SOFC. Firstly, the theoretical models of charge transport and multi-component mass transfer are established, respectively, and the two are coupled using the reaction rate calculation method. Then, employing an innovative combination of the representative elementary volume (REV) scale lattice Boltzmann method (LBM) and the finite-difference LBM, the potential and multi-component gases distributions are simulated to calculate the evaluated indicators, namely activation and concentration overpotential. Finally, considering various operational conditions, the simulation experiments are conducted to investigate the parametric effect on the performance of SOFC fueled by syngas. The results demonstrate that compared to the direct reforming way, the external syngas with lower CH4 component ratio is more favorable to the SOFC and the optimal ratio should be controlled within 0.2. The higher concentration of gas mixture and lower anode thickness both contribute to weakening the effect of concentration polarization. Especially, the performance of SOFC is improved when the concentration is 15 mol‧m−3 and the anode thickness is below 1.05 mm. With the increment of conductivity and operating temperature, the consumption of H2 gradually increases, enhancing the efficiency of reaction gas and reducing the economic cost. And the optimal operation temperature of SOFC is about 1073 K. Moreover, the anode thickness is a trade-off between the electrochemical reaction conditions of anode and cathode, as its variation affects both of them. [ABSTRACT FROM AUTHOR]

Zebra finches rely mainly on syllable phonology rather than on syllable sequence when they discriminate between two songs. However, they can also learn to discriminate two strings containing the same set of syllables by their sequence. How learning about the phonological characteristics of syllables and their sequence relate to each other and to the composition of the stimuli is still an open question. We compared whether and how the zebra finches' relative sensitivity for syllable phonology and syllable sequence depends on the differences between syllable strings. Two groups of zebra finches were trained in a Go-Left/Go-Right task to discriminate either between two strings in which each string contained a unique set of song syllables ('Different-syllables group') or two strings in which both strings contained the same set of syllables, but in a different sequential order ('Same-syllables group'). We assessed to what extent the birds in the two experimental groups attend to the spectral characteristics and the sequence of the syllables by measuring the responses to test strings consisting of spectral modifications or sequence changes. Our results showed no difference in the number of trials needed to discriminate strings consisting of either different or identical sets of syllables. Both experimental groups attended to changes in spectral features in a similar way, but the group for which both training strings consisted of the same set of syllables responded more strongly to changes in sequence than the group for which the training strings consisted of different sets of syllables. This outcome suggests the presence of an additional learning process to learn about syllable sequence when learning about syllable phonology is not sufficient to discriminate two strings. Our study thus demonstrates that the relative importance of syllable phonology and sequence depends on how these features vary among stimuli. This indicates cognitive flexibility in the acoustic features that songbirds might use in their song recognition. [ABSTRACT FROM AUTHOR]

Buddleja lindleyana Fort. is a garden ornamental plant with great potential for development and also a commonly used medicinal plant. To enrich its germplasm resources, the seeds of B. lindleyana were treated with colchicine solution with concentration gradients of 0.5%, 1.0%, 1.5%, 2.0% and 3.0% for 12-, 24- and 48-h respectively, and the water treatment was set as the control group. The purpose was to explore the effects of colchicine on the germination and mutagenic effect of B. lindleyana seeds at different concentrations and different times, to screen the appropriate combination of mutagenic concentration and time, to provide guidance for the construction of B. lindleyana mutation population in future research. The results were as follows: (1) Colchicine had an inhibitory effect on seed germination and seedling height of B. lindleyana seeds, and the higher the concentration, the more obvious the inhibitory effect. (2) After colchicine treatment, 30 mutant plants showed morphological variations such as leaf malformation, leaf color macular, early leaf bud germination, uneven leaf surface and leaf hyperplasia, among which 3.0% + 48-h treatment group had great potential to produce yellow-leaf plants. (3) Detection and analysis by flow cytometry revealed that among the 30 morphologically variant plants, there were 22 diploid plants, 3 tetraploid plants, and 5 chimera plants. Among them, tetraploids were mainly from colchicine concentration of 3.0% (2 plants) and 1.5% (1 plant), chimeras were mainly from colchicine concentration of 1.0% (2 plants), 1.5% (1 plant) and 3.0% (2 plants), and the seed soaking time was 48-h. (4) The length and width of guard cells and stomata were significantly different between diploid and tetraploid, and there were significant differences in leaf width and leaf shape index between tetraploid and diploid, but there were no significant differences in leaf length among diploid, tetraploid and chimera. In short, we got tetraploids and chimeras materials which were potentially useful cultivars of B. lindleyana and provided an effective identification method for polyploids of B. lindleyana. Key message: The appropriate combination of mutagenesis concentration and time was screened, and tetraploid B. lindleyana plants were successfully mutagenized, which provided technical support for the breeding research of B. lindleyana polyploidy. [ABSTRACT FROM AUTHOR]

The microstructure of the porous anode plays a crucial role in the mass transfer dynamics and electrochemical reaction of solid oxide fuel cells (SOFCs), significantly impacting their performance. This paper investigates the effect of microstructure of the porous anode on mass transfer and electrochemical reaction in SOFCs, which addresses the scarcity of research due to the complexity of microstructure modeling, offering supportive information for the structure optimization of SOFCs. Firstly, theoretical deductions of constructing microstructure and simulating mass transfer are conducted. Subsequently, a construction model is established based on the fractional Brownian motion (FBM) model to obtain different microstructures, encompassing various flow pore structures, triple phase boundary (TPB) structures, and inlet structures. Through a finite difference lattice Boltzmann method (LBM), the mass transfer is modeled to predict gas molar fraction distributions and calculate concentration overpotentials with different microstructures. Finally, thorough experiments are carried out to analyze the effect of structural parameters on mass transfer and electrochemical reaction. Taking the hydrogen-steam-nitrogen (H2-H2O-N2) ternary mass transfer as an example, the comparison results indicate that complex flow pore structures increase both the distance and resistance of mass transfer. To improve the performance of SOFCs, reducing flow pore complexity and increasing TPB length both mitigate the effect of concentration polarization. Moreover, the change of inlet structure suggests minimal impact on mass transfer and electrochemical reaction. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, various models for single gully debris flow assessment have been proposed. Due to various factors affecting the mechanisms of debris flows, these models face many problems during the prediction process. Based on the debris flow data of Yunnan, Yellow River Jishixia Reservoir Area, Beichuan County of Sichuan Province, two typical debris flow evaluation models, gray relation analysis and support vector machine, are used as examples to investigate the problems of parameter selection, sample data imbalance, generalization ability, spatial variability of the debris flow system, and the sample size. Relevant solutions are given to provide guidance for the future application of various single gully debris flow assessment models. [ABSTRACT FROM AUTHOR]

The ongoing outbreak of coronavirus disease 2019 (COVID-19) has spread rapidly on a global scale. Although it is clear that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted through human respiratory droplets and direct contact, the potential for aerosol transmission is poorly understood1–3. Here we investigated the aerodynamic nature of SARS-CoV-2 by measuring viral RNA in aerosols in different areas of two Wuhan hospitals during the outbreak of COVID-19 in February and March 2020. The concentration of SARS-CoV-2 RNA in aerosols that was detected in isolation wards and ventilated patient rooms was very low, but it was higher in the toilet areas used by the patients. Levels of airborne SARS-CoV-2 RNA in the most public areas was undetectable, except in two areas that were prone to crowding; this increase was possibly due to individuals infected with SARS-CoV-2 in the crowd. We found that some medical staff areas initially had high concentrations of viral RNA with aerosol size distributions that showed peaks in the submicrometre and/or supermicrometre regions; however, these levels were reduced to undetectable levels after implementation of rigorous sanitization procedures. Although we have not established the infectivity of the virus detected in these hospital areas, we propose that SARS-CoV-2 may have the potential to be transmitted through aerosols. Our results indicate that room ventilation, open space, sanitization of protective apparel, and proper use and disinfection of toilet areas can effectively limit the concentration of SARS-CoV-2 RNA in aerosols. Future work should explore the infectivity of aerosolized virus. Aerodynamic analysis of SARS-CoV-2 RNA in two hospitals in Wuhan indicates that SARS-CoV-2 may have the potential to be transmitted through aerosols, although the infectivity of the virus RNA was not established in this study. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nickel leaching from low-grade nickel matte (LGNM) using aqueous ferric chloride solution was studied. The influence of factors such as leaching temperature and concentration of ferric chloride on the nickel leaching ratio was investigated. The results show that increasing leaching temperature and concentration of ferric chloride increases the nickel leaching ratio. The overall nickel leaching process follows the unreacted shrinking core model, and the surface chemical reaction is the rate-controlling step. The activation energy and the reaction order of the nickel leaching process, controlled by the surface chemical reaction, were calculated to be 52.96 kJ·mol−1 and 0.5, respectively. Therefore, the kinetics equation for the nickel leaching was found to be 1 − (1 − α)1/3 = 7.18 × 104C0.5exp[− 52,960/(RT)]t. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM2.5) released by the burning of domestic solid fuels is an important air pollutant in the rural indoor environment in China. Here, personal exposure to PM2.5-induced oxidative damage resulting from household solid fuel combustion was examined in winter in rural areas of Guanzhong Basin, northwestern China. The volume-based average exogenous reactive oxygen species (exo-ROS) activities were 1943.7 ± 3668.0 and 1628.5 ± 2618.7 μM H2O2/min/m3 for 50 and 100 μL of PM2.5 extracts, respectively. While the different patterns were found for endogenous reactive oxygen species (endo-ROS), 465.8 ± 2427.4 and 1740.4 ± 2643.2 μM H2O2/min/m3 for 4 h exposed to 50 and 100 μL of PM2.5 extract. When the exposure time was extended to 24 h, endo-ROS activities were 3789.5 ± 4582.0 and 3534.8 ± 4595.6 μM H2O2/min/m3 for 50 and 100 μL of PM2.5 extracts, respectively. Among four common dwelling heating ways used in northwestern China, the highest ROS activity (160.4 μM H2O2/min/m3 for 4-h endo-ROS at 50 μL of PM2.5 extracts) was found for households using indoor coal chunks stove. The ROS activity in households using electric power heating was 2.9–15.9-fold lower than that in households using indoor coal chunks stove; thus, electric power heating was found to be the cleanest method for rural household heating. PM2.5-bound K+, organic carbon 1 (OC1), elemental carbon 1 (EC1), several polycyclic aromatic hydrocarbons (PAHs), and two hopanes species were observed to be significantly correlated with exo-ROS and 4-h endo-ROS, indicating that these chemical compounds and the sources in PM2.5 exposure samples may induce more ROS and affect human health strongly. The results indicate that heating methods used in rural households in winter can greatly impact the health of residents living in rural areas of northwestern China through personal exposure PM2.5-induced oxidative damage. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The breakup length and position of liquid jet are the important parameters to determine the atomization quality. The nonlinear dispersion equation is used to study the breakup length and position of liquid jet with cavitation bubbles in a coaxial swirling compressible gas flow. First, the comparison of the jet breakup characteristics under linear and nonlinear stability theories is made, and then the effects of swirling gas, fluid compressibility and cavitation bubbles on jet breakup length are analyzed. The results show that the second-order perturbation may accelerate the breakup of liquid jet and may also inhibit the jet breakup when nonlinear stability theory is taken. In addition, the breakup position of liquid jet may appear after the main droplet and also appear after the satellite droplet. With the increase in gas rotational strengths, fluid compressibility and bubble volume fractions, the breakup length decreases, which indicates that swirling gas, fluid compressibility and cavitation bubbles can accelerate the jet breakup to a certain extent. In general, the effect of fluid compressibility on jet breakup length is the most obvious. [ABSTRACT FROM AUTHOR]

Background and Objectives: Chiglitazar is a novel configuration-restricted non-thiazolidinedione peroxisome proliferator-activated receptor pan-agonist currently in the Phase III clinical development stage for type 2 diabetes mellitus patients. The objective of this Phase I study was to evaluate the pharmacokinetics, safety and tolerability of single and multiple doses of chiglitazar tablets taken orally and the effect of food on its pharmacokinetics in healthy Chinese subjects. Methods: A single-centre, open-label, randomised, two-stage Phase I study was carried out. In the first-stage study, we evaluated a single dose of 8, 16, or 32 mg, and multiple doses of 16 mg, taken once daily for 9 days. The effect of food consumption was also studied in this stage. In the second-stage study, a greater range of single doses (24, 48 or 72 mg) were further evaluated. Pharmacokinetics, safety and tolerability profiles were assessed at each study stage. Results: After a single oral dose of chiglitazar, at doses ranging from 8 to 72 mg, the maximum plasma concentration (Cmax) and area under the concentration–time curve (AUC) were proportionally increased (165–1599 ng/mL for the mean Cmax and 1356–12,584 ng·h/mL for the mean AUC0−t), with low inter-subject variability. There were no significant changes in the mean terminal phase half-life (t1/2), which ranged from 9.0 to 11.9 h, and the clearance and volume of distribution were similar for all evaluated doses. The results from the examination of multiple dose of 16 mg once daily for nine consecutive days showed that a steady-state condition was achieved by Day 6. There was no apparent accumulation of chiglitazar observed at Day 9, as compared with the first administration. While food increased the AUC0−t of chiglitazar by about 13%, there were no effects on other parameters, including Cmax, Tmax and t1/2. There were no serious or severe adverse events observed in the single- or multiple-dose studies. Conclusions: Chiglitazar tablets showed a good dose-dependent linear pharmacokinetic profile in the dose range of 8–72 mg. There was no accumulation after multiple daily administration of chiglitazar at a dose of 16 mg. High-fat/calorie food increased the absorption of the drug, but there were no significant changes in exposure and other pharmacokinetic parameters. Chiglitazar was safe and well tolerated in healthy Chinese subjects at the dose levels and administration regimens evaluated. [ABSTRACT FROM AUTHOR]

A flow mixing nozzle can produce satisfactory atomization for heavy oil. However, the study of the internal flow pattern of this nozzle, along with the spray morphology and its transformation, is currently limited to a low flow rate for the two-phase inlet. A flow mixing nozzle with a moderate inlet flow rate and various nozzle structures (H/D) was experimentally studied using a self-designed flow mixing nozzle and a self- constructed experimental platform, as described in this paper. The results demonstrate that at a moderate two-phase inlet flow rate, a clear cone is observed inside the nozzle that can be described by the cone angle and the dimensionless cone area. In short, as air inlet flow rate increases, the cone volume decreases, the jet atomization effect is enhanced, the distribution range narrows, the flow pattern changes to flow blurring, and the variation trend is the opposite of that when the water inlet flow rate is increased. An analysis of the experimental results demonstrate that the flow pattern and spray morphology of the flow mixing nozzle under a moderate inlet flow rate are determined by the inertial force of air and the inertial force and surface tension force of water. When the air flow rate is increased, the inertial force is enhanced, and the cone radial concavity is strengthened; or, the cone disappears. At this time, the spray morphology is mainly expressed as atomization. When the water flow rate increases, the water inertial force increases, and the cone changes to a radial protrusion. The spray morphology is mainly expressed as a jet or breakup. [ABSTRACT FROM AUTHOR]

Abstract: Effervescent jet breakup-based gas expansion disturbance was studied by the combination of experiment and numerical methods. A transparent outside-in-type atomizer was used to observe both internal and external gas-liquid flow behavior. Effects of internal flow patterns and flow rates on gas expansion bulge were experimentally studied. Further analysis on the disturbance of gas expansion on jet breakup was conducted through the numerical method. The present work showed the results of gas expansion disturbance exiting under various internal flow regimes. Increasing gas-liquid flow rates enlarges spray angle and gas expansion bulge, decreases adjacent gas bulges’ distance, and leads to a more stable spray. Detailed numerical results demonstrated that the gas expansion advancing jet breakup was enhanced by enlarging instantaneous gas volume and internal pressure. For efficient utilization of gas expansion potential energy, small bubble formation is suggested.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Black carbon (BC) aerosols were observed over Xi’an (XA) and Hong Kong (HK) to better compare its properties and sources in two geographically separate regions in China. High-BC (7.9 ± 3.3 μg·m−3) and -PM2.5 (182 ± 80.5 μg·m−3) concentrations were observed in XA, and these were much higher than those in HK (BC, 3.2 ± 0.9 μg·m−3; PM2.5, 34.5 ± 9.3 μg·m−3). The contribution of BC to PM2.5 in HK reached 10.7%, which was ~ 1.5 times than that in XA (7.6%). The results emphasized that BC played an important role in HK PM2.5. The diurnal distribution of HK BC was highly correlated with vehicle emissions during the daytime; it peaked during heavy traffic times. Whereas XA BC exhibited flat distribution owing to stable BC sources. It is not markedly driven by traffic patterns. Additionally, the potential source contribution function (PSCF) analysis showed that XA BC mainly originated from local emissions while nearly half of the HK BC originated from distant sources, such as industrial emissions from northeastern regions and ship emissions from marine regions. These anthropogenic BC sources were found to be regional in nature based on multilinear engine (ME-2) analysis. Specifically, the XA BC sources were dominated by three factors: 22.5% from coal burning, 19.6% from biomass burning, and 32.9% from vehicle emissions. In HK, the majority of BC contributions originated from vehicle and ship emissions (78.9%), while only 14.5% and 1.5% originated from coal and biomass burning from residential combustion, as well as industrial and power plants in inland China. [ABSTRACT FROM AUTHOR]

The breakup mechanism and instability of a power law liquid jet are investigated in this study. The power law model is used to account for the non-Newtonian behavior of the liquid fluid. A new theoretical model is established to explain the breakup of a power law liquid jet with axisymmetric and asymmetric disturbances, which moves in a swirling gas. The corresponding dispersion relation is derived by a linear approximation, and it is applicable for both shear-thinning and shear-thickening liquid jets. Analysis results are calculated based on the temporal mode. The analysis includes the effects of the generalized Reynolds number, the Weber number, the power law exponent, and the air swirl strength on the breakup of the jet. Results show that the shear-thickening liquid jet is more unstable than its Newtonian and shear-thinning counterparts when the effect of the air swirl is taken into account. The axisymmetric mode can be the dominant mode on the power law jet breakup when the air swirl strength is strong enough, while the non-axisymmetric mode is the domination on the instability of the power liquid jet with a high We and a low Ren. It is also found that the air swirl is a stabilizing factor on the breakup of the power law liquid jet. Furthermore, the instability characteristics are different for different power law exponents. The amplitude of the power law liquid jet surface on the temporal mode is also discussed under different air swirl strengths. [ABSTRACT FROM AUTHOR]

Exposure to airborne particulate matter (PM) has been associated with various adverse health effects, including severe pulmonary and cardiovascular effects. PM consists of different chemical components that vary with microenvironments in urban areas and pose challenges to assess personal exposure. In Hong Kong, more than 70% of the population commutes through roadway and railway public transport. This study aims to determine the oxidative potential and role of aerosol carbon and water-soluble metals in fine ( d < 2.5 μm) and coarse PM (2.5 < d <10 μm) in public transport systems including underground (UG) subway, above-ground (AG) train, and buses (BUS). Metals such as Fe, Cr, Mo, Pb, Ni, and V from UG, AG, and BUS routes exhibited much lower solubility compared with ambient PM. The cell toxicity of PM in these transport microenvironments was also analyzed in vitro and compared with urban ambient environments. Strong positive associations were observed for reactive oxygen species (ROS) with water-soluble metals (Cr, Cu, Fe, Mn, Ni, V, Mo; R > 0.70) and organic and elemental carbon (OCEC) ( R > 0.85) for UG and AG routes. In addition, PM from UG and AG routes generated 3-4-fold (in PM) and 40-50-fold (in coarse PM) less ROS compared to urban sites, suggesting PM in these public transport microenvironments may not be intrinsically redox active than in urban ambient, and water solubility of metals seems to have played an important role in it. [ABSTRACT FROM AUTHOR]

To investigate the chemical properties of particulate matter (PM) in different public transport microenvironments in Hong Kong, the coarse (2.5-10 μm) and fine (<2.5 μm) PM samples were collected in three different types of transport modes including Mass Transit Railway (MTR)-Aboveground (AG), MTR Underground (UG), and Bus routes from October 2013 to April 2014. Average PM concentrations through UG, AG, and Bus routes were 47.9, 86.8, and 43.8 μg m, respectively, whereas the coarse PM concentrations were 4-5 folds less. The PM total metal concentrations of AG route were 2.3 and 3.7 times of UG and BUS routes, respectively, compared to those in the other two routes. The most abundant metals at three stations in PM and coarse PM were quite similar and mainly generated by frictional processes of wheels, rails, and brakes of the system as well as by the mechanical wearing of these parts. The most abundant PAH in three routes in PM was ATRQN, followed by 2-MNA, and the sum of them contributed to 35 and 42% of total PAHs in coarse PM and PM, respectively. Crude oils, lubricant oil, diesel emissions would be the major sources of PAHs from MTR aboveground stations. The relative abundance of the n-alkanes among different samples was similar to the PAHs and the carbon preference index (CPI) values of the whole n-alkanes range were consistently from 0.99 to 1.04 among all samples indicating the significant contribution from the vehicle exhaust and fossil fuel burning. The concentrations of hopanes and steranes were higher in PM than in coarse PM due to diesel and coal burning. These results may provide a unique opportunity to investigate source specific contribution of the PM pollutants to the commuter exposure in public transport. [ABSTRACT FROM AUTHOR]

Desilication kinetics of calcined boron mud (CBM) occurring in molten sodium hydroxide media was investigated. The effects of factors such as reaction temperature and NaOH-to-CBM mass ratio on silicon extraction efficiency were studied. The results show that silicon extraction efficiency increases with increasing the reaction time and NaOH-to-CBM mass ratio. There are two stages for the desilication process of the calcined boron mud. The overall desilication process follows the shrinking-core model, and the first and second stages of the process were determined to obey the shrinking-core model for surface chemical reaction and the diffusion through the product layer, respectively. The activation energies of the first and second stages were calculated to be 44.78 kJ/mol and 15.94 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

A dispersion equation for studying the relation between temporal and spatial stability of a liquid jet containing vapor bubbles in coaxial swirling compressible flow is presented by the use of two linear theories, temporal theory and spatial theory. The mathematical model and the corresponding solving methods to the two linear theories are verified by comparing with the data in the literature. Furthermore, the relation between temporal and spatial stability of a liquid jet containing vapor bubbles is investigated, and the effects of the gas rotational strength, the gas Mach number and the bubble volume fraction on the difference between temporal and spatial stability are then discussed. Some conclusions can be drawn from the results of this investigation, for a liquid jet with the given physical parameters, (1) there are no significant differences between temporal theory and spatial theory in respect of the dominant mode of disturbance on the jet surface, the dominant characteristic wave frequency and the smallest atomized droplet, (2) the interfacial disturbance amplitude with spatial theory is apparently larger than the disturbance amplitude with temporal theory, (3) the coaxial rotation of the surrounding gas is a factor to affect the difference between temporal and spatial theory, and there is a certain value of the non-dimensional gas rotational strength ( E = 1.5) which makes the difference between the two linear theories reach the peak, (4) the effect of the gas compressibility is to increase the difference between temporal and spatial theory, and the effect of the gas compressibility is going to increase rapidly when the gas Mach number Ma ≥ 0.5, and (5) the effect of bubble volume fraction is to increase the difference between temporal and spatial theory, and the difference value is approximately proportional to the increasing of bubble volume fraction. [ABSTRACT FROM AUTHOR]

The effect of several parameters on the recovery of silicon dioxide from calcined boron mud (CBM) such as stirring speed, temperature, sodium silicate concentration, and carbonation time was studied. The recovery of silicon dioxide is 88 % when the stirring speed is 450 r·min, temperature is 60 °C, sodium silicate concentration is 1 mol·L, and the carbonation time is 6 h. The effect of carbonation time on the recovery of silicon dioxide is divided into three kinetic regimes, and the carbonation process of sodium silicate solution follows a second-order reaction based on the double-film theory model. The apparent rate constant of the three kinetic regimes is 0.064, 3.178, and 1.130 L·h·mol, respectively. The amorphous SiO products obtained by carbonating the purified solution have 99.6 % purity and are spherical with diameters of about 100 nm. [ABSTRACT FROM AUTHOR]

Extracting BO from calcined boron mud (CBM) was studied. The effect of factors such as reaction temperature and NaOH-to-CBM mass ratio on BO extraction efficiency was investigated. The results show that increasing reaction temperature and NaOH-to-CBM mass ratio increases BO extraction efficiency. There are two stages for the BO extracting process: 0-20 min is the first stage, which is rapid; 20-50 min is the second stage, which is slower than the first stage. The overall extracting process follows the shrinking core model, and the first and second stages are determined to obey the surface chemical reaction model and the diffusion through the products layer model, respectively. The activation energies of the first and second stages are calculated to be 41.74 and 15.43 kJ·mol, respectively. The BO extracting kinetics equations of the first and second stages are also obtained. [ABSTRACT FROM AUTHOR]

A novel method was developed for extracting alumina (AlO) from fly ash using an ammonium hydrogen sulfate (NHHSO) roasting process, and the thermodynamics and kinetics of this method were investigated. The thermodynamic results were verified experimentally. Thermodynamic calculations show that mullite present in the fly ash can react with NHHSO in the 298-723 K range. Process optimization reveals that the extraction rate can reach up to 90.95% when the fly ash reacts with NHHSO at a 1:8 mole ratio of AlO/NHHSO at 673 K for 60 min. Kinetic analysis indicates that the NHHSO roasting process follows the shrinking unreacted core model, and inner diffusion through the product layer is the rate-controlling step. The activation energy is calculated to be 16.627 kJ/mol; and the kinetic equation can be expressed as 1 − (2/3) α − (1 − α) = 0.0374 t exp[−16627/( RT)], where α is the extraction rate and t is the roasting temperature. [ABSTRACT FROM AUTHOR]

Supercavitation in the diesel nozzle increases the instability of droplets in part due to the two-phase mixture, while the effect of cavitation bubbles on the instability of drops is still unclear. In order to investigate the breakup of cavitation bubbles within the diesel droplet, a new mathematical model describing the disturbance growth rate of the diesel bubble instability is developed. The new mathematical model is applied to predict the effects of fluids viscosity on the stability of cavitation bubbles. The predicted values reveal that the comprehensive effect of fluids viscosity makes cavitation bubbles more stable. Compared with the viscosities of air and cavitation bubble, the diesel droplet's viscosity plays a dominant role on the stability of cavitation bubbles. Furthermore, based on the modified bubble breakup criterion, the effects of bubble growth speed, sound speed, droplet viscosity, droplet density, and bubble-droplet radius ratio on the breakup time and the breakup radius of cavitation bubbles are studied respectively. It is found that a bubble with large bubble-droplet radius ratio has the initial condition for breaking easily. For a given bubble-droplet radius ratio (0.2), as the bubble growth speed increases (from 2 m/s to 60 m/s), the bubble breakup time decreases(from 3.59 μs to 0.17 μs) rapidly. Both the greater diesel droplet viscosity and the greater diesel droplet density result in the increase of the breakup time. With increasing initial bubble-droplet radius ratio (from 0.2 to 0.8), the bubble breakup radius decreases (from 8.86 μm to 6.23 μm). There is a limited breakup radius for a bubble with a certain initial bubble-droplet radius ratio. The mathematical model and the modified bubble breakup criterion are helpful to improve the study on the breakup mechanism of the secondary diesel droplet under the condition of supercavitation. [ABSTRACT FROM AUTHOR]

Instability and breakup of a viscous annular liquid sheet that is exposed to co-flowing inner and outer gas streams have been investigated using a nonlinear spatial stability analysis. A perturbation expansion method is used with the initial amplitude of the disturbance as the perturbation parameter. The evolution of the two gas–liquid interfaces is tracked until the sheet breaks up and the breakup length is determined. The model is validated by comparison with available experimental data. The effects of liquid swirl strength, gas-to-liquid density ratio, radius of curvature ratio, and liquid viscosity on the sheet instability and breakup have been studied. The results show that at very low values of liquid swirl, it has a stabilizing effect on sheet breakup, but as the swirl strength increases, it strongly destabilizes the sheet. Also, with increasing swirl strength, the occurrence of the large surface deformations moves from the inner interface to the outer interface. The sheet breakup length increases slightly and then decreases rapidly with an increase in liquid swirl strength. Without liquid swirl, the axisymmetric mode is the dominant instability mode. However, with increasing liquid swirl strength, the higher helical modes become dominant and the breakup becomes increasingly asymmetric. When the undisturbed liquid sheet has a purely axial motion, the inner gas stream is more effective in sheet breakup than the outer gas stream. In the presence of liquid swirl, the outer gas stream is more disruptive than the inner gas stream. The breakup length becomes shorter as gas-to-liquid density ratio and the radius of curvature ratio increases. Increase in liquid viscosity tends to slow the disturbance growth and increases the sheet breakup length. [ABSTRACT FROM AUTHOR]

Purpose: Chidamide (CS055/HBI-8000) is a new benzamide class of histone deacetylase inhibitor with marked anti-tumor activity. This study reports the phase I results. Methods: Patients with advanced solid tumors or lymphomas received oral doses of 5, 10, 17.5, 25, 32.5, or 50 mg chidamide either twice (BIW) or three times (TIW) per week for 4 consecutive weeks every 6 weeks. Safety, characteristics of pharmacokinetics (PK) and pharmacodynamics (PD), and preliminary efficacy were evaluated. Results: A total of 31 patients were enrolled. No DLTs were identified in the BIW cohorts up to 50 mg. DLTs were grade 3 diarrhea and vomiting in two patients in the TIW cohort at 50 mg, respectively. PK analysis revealed t of 16.8-18.3 h, T of 1-2 h in most cases, and a dose-related increase in C and AUC. Significant induction of histone H3 acetylation in peripheral white blood cells was observed after a single dose of chidamide. Four patients with T-cell lymphomas and 1 patient with submandibular adenoid cystic carcinoma achieved a partial response. Conclusions: Chidamide was generally well tolerated in patients with advanced solid tumors or lymphomas in the tested regimens. Favorable PK and PD profiles, as well as encouraging preliminary anti-tumor activity, were demonstrated. [ABSTRACT FROM AUTHOR]

Purpose: Chidamide (CS055/HBI-8000) is a new histone deacetylase (HDAC) inhibitor of the benzamide class currently under clinical development in cancer indications. This study reports the in vitro and in vivo antitumor characteristics of the compound. Methods: Selectivity and potency of chidamide in inhibition of HDAC isotypes were analyzed by using a panel of human recombinant HDAC proteins. Tumor cell lines either in culture or inoculated in nude mice were used for the evaluation of the compound's antitumor activity. To investigate the immune cell-mediated antitumor effect, isolated peripheral blood mononuclear cells from healthy donors were treated with chidamide, and cytotoxicity and expression of relevant surface proteins were analyzed. Microarray gene expression studies were performed on peripheral white blood cells from two T-cell lymphoma patients treated with chidamide. Results: Chidamide was found to be a low nanomolar inhibitor of HDAC1, 2, 3, and 10, the HDAC isotypes well documented to be associated with the malignant phenotype. Significant and broad spectrum in vitro and in vivo antitumor activity, including a wide therapeutic index, was observed. Chidamide was also shown to enhance the cytotoxic effect of human peripheral mononuclear cells ex vivo on K562 target cells, accompanied by the upregulation of proteins involved in NK cell functions. Furthermore, the expression of a number of genes involved in immune cell-mediated antitumor activity was observed to be upregulated in peripheral white blood cells from two T-cell lymphoma patients who responded to chidamide administration. Conclusions: The results presented in this study provide evidence that chidamide has potential applicability for the treatment of a variety of tumor types, either as a single agent or in combination therapies. [ABSTRACT FROM AUTHOR]

A low temperature drift curvature-compensated complementary metal oxide semiconductor (CMOS) bandgap reference is proposed. A dual-differential-pair amplifier was employed to add compensation with a high-order term of Tln T ( T is the thermodynamic temperature) to the traditional 1st-order compensated bandgap. To reduce the offset of the amplifier and noise of the bandgap reference, input differential metal oxide semiconductor field-effect transistors (MOSFETs) of large size were used in the amplifier and to keep a low quiescent current, these MOSFETs all work in weak inversion. The voltage reference's temperature curvature has been further corrected by trimming a switched resistor network. The circuit delivers an output voltage of 3 V with a low dropout regulator (LDO). The chip was fabricated in Taiwan Semiconductor Manufacturing Company (TSMC)'s 0.35-μm CMOS process, and the temperature coefficient (TC) was measured to be only 2.1×10/°C over the temperature range of −40-125 °C after trimming. The power supply rejection (PSR) was −100 dB @ DC and the noise was 42 μV (rms) from 0.1 to 10 Hz. [ABSTRACT FROM AUTHOR]

Activating mutations of c-kit at codon 816 (Asp816) have been identified in variety of malignancies, including acute myeloid leukemia (AML), mastocytosis and germ cell tumors. The mutant c-Kit receptor confers cytokine independence and induces tumorigenicity. However, the molecular mechanisms, particularly the changes in the signal transduction pathways, responsible for these biological effects induced by mutant c-Kit are largely undefined. Using the human embryonic kidney cell line, 293, we show in the current report that constitutive activation of STAT3 and STAT1 is associated with D816H mutant c-Kit. Transfection of dominant negative STAT3, but not STAT1 inhibits mutant c-Kit mediated anchorage-independent growth in vitro and tumor formation in vivo. Expression of constitutively activated STAT3 restores the mutant c-Kit receptor's transforming ability in 293 cells. These results demonstrate that activation of STAT3 by Asp816 mutant c-Kit is required for the anchorage-independent growth and tumorigenicity induced by Asp816 mutant c-Kit. Oncogene (2001) 20, 4528–4536. [ABSTRACT FROM AUTHOR]

Introduction: Breast cancer is the leading cause of cancer death in women worldwide. Elevated expression of c-Myc is a frequent genetic abnormality seen in this malignancy. For a better understanding of its role in maintaining the malignant phenotype, we used RNA interference (RNAi) directed against c-Myc in our study. RNAi provides a new, reliable method to investigate gene function and has the potential for gene therapy. The aim of the study was to examine the anti-tumor effects elicited by a decrease in the protein level of c-Myc by RNAi and its possible mechanism of effects in MCF-7 cells. Method: A plasmid-based polymerase III promoter system was used to deliver and express short interfering RNA (siRNA) targeting c-myc to reduce its expression in MCF-7 cells. Western blot analysis was used to measure the protein level of c-Myc. We assessed the effects of c-Myc silencing on tumor growth by a growth curve, by soft agar assay and by nude mice experiments in vivo. Standard fluorescence-activated cell sorter analysis and TdT-mediated dUTP nick end labelling assay were used to determine apoptosis of the cells. Results: Our data showed that plasmids expressing siRNA against c-myc markedly and durably reduced its expression in MCF-7 cells by up to 80%, decreased the growth rate of MCF-7 cells, inhibited colony formation in soft agar and significantly reduced tumor growth in nude mice. We also found that depletion of c-Myc in this manner promoted apoptosis of MCF-7 cells upon serum withdrawal. Conclusion: c-Myc has a pivotal function in the development of breast cancer. Our data show that decreasing the c-Myc protein level in MCF-7 cells by RNAi could significantly inhibit tumor growth both in vitro and in vivo, and imply the therapeutic potential of RNAi on the treatment of breast cancer by targeting overexpression oncogenes such as c-myc, and c-myc might be a potential therapeutic target for human breast cancer.

Abstract The nervous and vascular systems, although functionally different, share many common regulators of function maintenance. Long non‐coding RNAs (lncRNAs) are important players in many biological processes and human disorders. We previously identified a role of MALAT1 in microvascular dysfunction. However, its role in neurodegeneration is still unknown. Here, we used the eye as the model to investigate the role of MALAT1 in retinal neurodegeneration. We show that MALAT1 expression is significantly up‐regulated in the retinas, Müller cells, and primary retinal ganglion cells (RGCs) upon stress. MALAT1 knockdown reduces reactive gliosis, Müller cell activation, and RGC survival in vivo and in vitro. MALAT1‐CREB binding maintains CREB phosphorylation by inhibiting PP2A‐mediated dephosphorylation, which leads to continuous CREB signaling activation. Clinical and animal experimentation suggests that MALAT1 dysfunction is implicated in neurodegenerative processes and several human disorders. Collectively, this study reveals that MALAT1 might regulate the development of retinal neurodegeneration through CREB signaling.