Facilitated movement of inertial Brownian motors driven by a load under an asymmetric potential

Based on recent work [L. Machura, M. Kostur, P. Talkner, J. Luczka, and P. Hanggi, Phys. Rev. Lett. 98, 040601 (2007)], we extend the study of inertial Brownian motors to the case of an asymmetric potential. It is found that some transport phenomena appear in the presence of an asymmetric potential. Within tailored parameter regimes, there exists two optimal values of the load at which the mean velocity takes its maximum, which means that a load can facilitate the transport in the two parameter regimes. In addition, the phenomenon of multiple current reversals can be observed when the load is increased.Comment: 7 pages, 3 figure

Currency Crisis in Thailand: The Leading Indicators

Among the developing countries across the globe, those in Southeast Asia have experienced the most economic success within the last several decades. The ASEAN-5’s (Indonesia, Malaysia, the Philippines, Singapore, and Thailand) outstanding economic performance earned them, among other Asian countries, the title Asian Tigers. In the last decade, the annual growth rate of the ASEAN-5 has risen close to 8 %. The economic growth that the Asian Tigers were experiencing seemed indestructible, until the summer of 1997

Sweet cherry:composition, postharvest preservation, processing and trends for its future use

Background Sweet cherries (Prunus avium L.) are a nutritious fruit which are rich in polyphenols and have high antioxidant potential. Most sweet cherries are consumed fresh and a small proportion of the total sweet cherries production is value added to make processed food products. Sweet cherries are highly perishable fruit with a short harvest season, therefore extensive preservation and processing methods have been developed for the extension of their shelf-life and distribution of their products. Scope and Approach In this review, the main physicochemical properties of sweet cherries, as well as bioactive components and their determination methods are described. The study emphasises the recent progress of postharvest technology, such as controlled/modified atmosphere storage, edible coatings, irradiation, and biological control agents, to maintain sweet cherries for the fresh market. Valorisations of second-grade sweet cherries, as well as trends for the diversification of cherry products for future studies are also discussed. Key Findings and Conclusions Sweet cherry fruit have a short harvest period and marketing window. The major loss in quality after harvest include moisture loss, softening, decay and stem browning. Without compromising their eating quality, the extension in fruit quality and shelf-life for sweet cherries is feasible by means of combination of good handling practice and applications of appropriate postharvest technology. With the drive of health-food sector, the potential of using second class cherries including cherry stems as a source of bioactive compound extraction is high, as cherry fruit is well-known for being rich in health-promoting components

The application of low pressure storage to maintain the quality of zucchinis

Zucchini (Cucurbita pepo var. cylindrica) were stored at low pressure (4 kPa) at 10°C at 100% relative humidity for 11 days. Fruit quality was examined upon removal and after being transferred to normal atmosphere (101 kPa) at 20°C for three days. Zucchinis stored at low pressure exhibited a 50% reduction in stem-end browning compared with fruit stored at atmospheric pressure (101 kPa) at 10°C. The benefit of low pressure treatment was maintained after the additional three days storage at normal atmospheric pressure at 20°C. Indeed, low pressure treated fruit transferred to regular atmosphere 20°C for three days possessed a significantly lower incidence of postharvest rot compared to fruit stored at regular atmospheric pressure at 10°C. Zucchinis stored at low pressure showed higher levels of acceptability (28% and 36%, respectively) compared to fruit stored at regular atmospheres at 10°C for both assessment times.<br/

Sustainable Growth and Ethics: a Study of Business Ethics in Vietnam Between Business Students and Working Adults

Sustainable growth is not only the ultimate goal of business corporations but also the primary target of local governments as well as regional and global economies. One of the cornerstones of sustainable growth is ethics. An ethical organizational culture provides support to achieve sustainable growth. Ethical leaders and employees have great potential for positive influence on decisions and behaviors that lead to sustainability. Ethical behavior, therefore, is expected of everyone in the modern workplace. As a result, companies devote many resources and training programs to make sure their employees live according to the high ethical standards. This study provides an analysis of Vietnamese business students&rsquo; level of ethical maturity based on gender, education, work experience, and ethics training. The results of data from 260 business students compared with 704 working adults in Vietnam demonstrate that students have a significantly higher level of ethical maturity. Furthermore, gender and work experience are significant factors in ethical maturity. While more educated respondents and those who had completed an ethics course did have a higher level of ethical maturity, the results were not statistically significant. Analysis of the results along with suggestions and implications are provided

Screening the effect of four ultrasound-assisted extraction parameters on hesperidin and phenolic acid content of aqueous citrus pomace extracts

Polyphenols of citrus by-products, due to their antioxidant and antimicrobial activities, could be valorized by pharmaceutical and food industries, adding a value to the citrus processing companies. A number of studies have investigated the effect of ultrasound-assisted extraction (UAE) conditions on the recovery of phenolics derived from citrus waste using both organic solvents or mixed aqueous solvent systems. To maximize efficiency, UAE conditions should be tailored to the physical parameters of the solvent(s) employed. The aim of this study was to investigate the effect of four UAE parameters: particle size (1.40–2.80 mm), extraction time (10–60 min), extraction temperature (23–50 °C) and ultrasonic power (150–250 W) on the simultaneous recovery of p-coumaric acid, caffeic acid, chlorogenic acid, and hesperidin from citrus waste using pure water as a solvent. High-performance liquid chromatography (HPLC) was employed for the identification and quantification of the cited compounds. Particle size was determined to be an important parameter affecting compound recovery, with the exception of chlorogenic acid. A particle size of 1.40 mm resulted in the highest recovery of p-coumaric and caffeic acids (0.25 and 0.58 mg/g, respectively), while higher hesperidin yields were achieved from the particle sizes of 2.00 and 1.40 mm (6.44 and 6.27 mg/g, respectively). Extraction temperature significantly affected only the recovery of the flavanone glycoside (P&lt;0.05). As the extraction temperature increased from 30 to 50 °C the recovery of hesperidin increased from 6.59 to 7.84 mg/g, respectively. Neither extraction time nor ultrasonic power significantly affected the recovery of any individual phenolic compound

Use of response surface methodology (RSM) to optimize pea starch-chitosan novel edible film formulation

The aim of this study was to develop an optimal formulation for preparation of an edible film from chitosan, pea starch and glycerol using response surface methodology (RSM). Three independent variables were assigned comprising chitosan (1-2%), pea starch (0.5-1.5%) and glycerol (0.5-1%) to design an empirical model best fit in physical, mechanical and barrier attributes. Impacts of independent variables on thickness, moisture content (MC), solubility, tensile strength (TS), elastic modulus (EM), elongation at break (EB) and water vapor permeability (WVP) of films were evaluated. All the parameters were found to have significant effects (p&lt;0.05) on physical and mechanical properties of film. The optimal formulation for preparation of edible film from chitosan, pea starch and glycerol was 1% chitosan, 1.5% pea starch and 0.5% glycerol. An edible film with good physical and mechanical properties can be prepared with this formulation and thus this formulation can be further applied for testing on coating for fruit and vegetables

Impact of different solvents on the recovery of bioactive compounds and antioxidant properties from lemon (Citrus limon L.) pomace waste

The effects of different solvents on the recovery of (i) extractable solids (ES), (ii) total phenolic compounds (TPC), (iii) total flavonoid content (TFC), (iv) vitamin C, and (v) antioxidant activity from lemon pomace waste were investigated. The results revealed that solvents significantly affected the recovery of ES, TPC, TFC, and antioxidant properties. Absolute methanol and 50% acetone resulted in the highest extraction yields of TPC, whereas absolute methanol resulted in the highest extraction of TFC, and water had the highest recovery of vitamin C. 50% ethanol, and 50% acetone had higher extraction yields for TPC, and TFC, as well as higher antioxidant activity compared with their absolute solvents and water. TPC and TFC were shown to be the major components contributing to the antioxidant activity of lemon pomace

Optimizing a sustainable ultrasound assisted extraction method for the recovery of polyphenols from lemon by-products:comparison with hot water and organic solvent extractions

Response surface methodology (RSM) based on a three-factor and three-level Box–Behnken design was employed for optimizing the aqueous ultrasound-assisted extraction (AUAE) conditions, including extraction time (35–45 min), extraction temperature (45–55 °C) and ultrasonic power (150–250 W), for the recovery of total phenolic content (TPC) and rutin from lemon by-products. The independent variables and their values were selected on the basis of preliminary experiments, where the effects of five extraction parameters (particle size, extraction time and temperature, ultrasonic power and sample-to-solvent ratio) on TPC and rutin extraction yields were investigated. The yields of TPC and rutin were studied using a second-order polynomial equation. The optimum AUAE conditions for TPC were extraction time of 45 min, extraction temperature of 50 °C and ultrasonic power of 250 W with a predicted value of 18.10 ± 0.24 mg GAE/g dw, while the optimum AUAE conditions for rutin were extraction time of 35 min, extraction temperature of 48 °C and ultrasonic power of 150W with a predicted value of 3.20 ± 0.12 mg/g dw. The extracts obtained at the optimum AUAE conditions were compared with those obtained by a hot water and an organic solvent conventional extraction in terms of TPC, total flavonoid content (TF) and antioxidant capacity. The extracts obtained by AUAE had the same TPC, TF and ferric reducing antioxidant power as those achieved by organic solvent conventional extraction. However, hot water extraction led to extracts with the highest flavonoid content and antioxidant capacity. Scanning electron microscopy analysis showed that all the extraction methods led to cell damage to varying extents