RESUMEN
In the drum mixing of particulate polymers, segregation may occur. By measuring the mixing status in real time, it is possible to implement corrective measures to prevent separation and improve the efficiency of the process. This study aims to develop and validate a real-time vision system designed to monitor the mixing process of polymeric particles in a rotary drum mixer, employing a novel centroid-based model for determining the mixing index. The proposed centroid-based model is capable of addressing the radial particle segregation issue without the need for extra image-processing procedures like image subdivision or pixel randomization. This innovative approach greatly improves computational efficiency by processing over 68 image frames per second. The new processing method is 2.8 times faster than the gray-level co-occurrence matrix method and 21.6 times faster than the Lacey index approach. This significantly improves real-time monitoring capabilities and enables real-time image processing using only affordable single-board computers and webcams. The proposed vision-based system for monitoring rotary drum mixing has undergone validation via cross-validation using discrete element method simulations, ensuring its accuracy and reliability.
RESUMEN
Park et al. showed that the Shannon entropy of the probability distribution of a single random variable for far-field profiles (FFPs) in deformed microcavity lasers can efficiently measure the directionality of deformed microcavity lasers. In this study, we instead consider two random variables of FFPs with joint probability distributions and introduce the decomposed (Shannon) entropy for the peak intensities of directional emissions. This provides a new foundation such that the decomposed entropy can estimate the degree of the output power at given FFPs without any further information.
RESUMEN
In this work, alternative evaporation processes for PLA production were designed with economic assessment. The suggested processes are the multiple-effect evaporation (MEE) process and thermal vapor recompression (TVR)-assisted evaporation process. First, the MEE process can efficiently reuse waste heat by additional column installation, thereby reducing the steam energy consumption. The proposed MEE process involves five columns, and after the evaporation in each column, the waste heat of the emitted vapor is reused to heat steam in the reboiler of the next column. Second, the suggested TVR-assisted evaporation process utilizes an additional steam ejector and recovers waste heat from the emitted vapor by increasing the pressure using high-pressure driving steam at the steam ejector. Each alternative process was modeled to predict the steam energy consumption, and to determine the cost-optimal process; the total annualized cost (TAC) of each alternative process was calculated as evaluation criteria. In the simulation results, the alternative processes using MEE and TVR reduced the steam consumption by 71.36% and 89.97%, respectively, compared to the conventional process. As a result of economic assessment, the cost-optimal process is the alternative process using TVR and the TAC can be decreased by approximately 90%.
RESUMEN
The increasing problem of antibiotic resistance among pathogenic bacteria requires novel strategies for the construction of multiple, joined genes of antimicrobial agents. The strategy used in this study involved synthesis of a cDNA-encoding hinnavin II/alpha-melanocyte-stimulating hormone (hin/MSH) hybrid peptide, which was cloned into the pET32a (+) vector to allow expression of the hybrid peptide as a fusion protein in Escherichia coli BL21 (DE3). The resulting expression of fusion protein Trx-hin/MSH could reach up to 20% of the total cell proteins. More than 50% of the target protein was in a soluble form. The target fusion protein from the soluble fraction, Trx-hin/MSH, was easily purified by Ni(2+)-chelating chromatography. Then, enterokinase cleavage effectively cleaved the Trx-hin/MSH to release the recombinant hin/MSH (rhin/MSH) hybrid peptide. After removing the contaminants, we purified the recombinant hybrid peptide to homogeneity by reversed-phase FPLC and obtained 210 mg of pure, active rhin/MSH from 800 ml of culture medium. Antimicrobial activity assay demonstrated that rhin/MSH had a broader spectrum of activity than did the parental hinnavin II or MSH against fungi and Gram-positive and Gram-negative bacteria. These results suggest an efficient method for producing high-level expression of various kinds of antimicrobial peptides that are toxic to the host, a reliable and simple method for producing different hybrid peptides for biological studies.
Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Proteínas Recombinantes de Fusión/biosíntesis , alfa-MSH/biosíntesis , Secuencia de Aminoácidos , Péptidos Catiónicos Antimicrobianos/biosíntesis , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/farmacología , Bacterias/efectos de los fármacos , Secuencia de Bases , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , alfa-MSH/genética , alfa-MSH/farmacologíaRESUMEN
The first objective of this study was to determine the kinematic variability of the lower extremity joints using methods from the mathematical chaos theory in a normal walking environment in conjunction with a large population of healthy young adults. The second objective was to test the hypothesis that variability characteristics are different between joints and to further investigate differences between male and female and right and left subgroups. A total of forty young healthy subjects (20 males: 24.1+/-3.1 years; 20 females: 22.5+/-3.2 years) volunteered, and their joint motions were captured while walking on a treadmill for 90 s in order to estimate Lyapunov Exponent (LE) values. Means and standard deviations of the LEs ranged from 0.035+/-0.016 (right ankle) to 0.073+/-0.023 (left knee) for the male subjects and from 0.028+/-0.014 (left ankle) to 0.065+/-0.028 (right hip) for the female subjects. Between the males and females, differences in LEs were observed to be statistically significant only for the left knee. There were no statistically significant differences between the right and left sides of the joints. However, differences between joints were statistically significant except between the hip and knee. These results are the first such comparison of the variability in the lower extremity without the confounding effect of walking speed on the variability of joint motions, and can serve as a normative database.