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Semen Astragali Complanati: an ethnopharmacological, phytochemical and pharmacological review
No full textEthnopharmacological Relevance: Semen Astragali Complanati (SAC), the dried ripe seed of Flatstem Milkvetch (Astragalus complanatus Bunge) (Leguminosae), is commonly used in traditional Chinese medicine (TCM) for treating muscle, liver, kidney, blood, skin and reproductive system diseases.
Materials and Methods: Relevant information about SAC was gathered via “Google Scholar”, “ISI Web of Knowledge”, “PubMed”, “ScienceDirect”, “Medline Plus”, “ACS”, “CNKI” and “Wiley Online Library” and from books in local libraries.
Results: The major contents of SAC include fatty acids, amino acids, polysaccharides, flavonoids, triterpene glycosides and trace elements. Previous scientific studies have reported that SAC exhibits a number of therapeutic effects on chronic diseases such as cardiovascular diseases, diabetes mellitus and cancers. It has been found that flavonoids are the main bioactive component in SAC. However most of the previous studies have shown the effects brought by the total flavonoid fraction extracted from SAC only; further studies are warranted for the biological effects produced by individual components. There are only a few studies on the toxicity of SAC and the overall results show that its toxicity is quite low or even non-existent.
Conclusions: SAC is a valuable TCM herb with multiple pharmacological effects for treating some chronic diseases. More studies on SAC will help us to have a better understanding of its pharmacological mechanisms so as to provide more scientific evidence to explain its traditional uses, identify its therapeutic potential on other diseases and understand its possible harmful effects. Based on previous studies, it is easy to identify that antioxidant effect of SAC might play an important role on its pharmacological effects. Studying the effects of SAC on handling intracellular reactive oxygen species may be a potential direction to help understanding the molecular mechanisms of SAC on preventing and/or treating chronic diseases
A simple design for strongly emissive sky-blue phosphorescent neutral rhenium complexes: synthesis, photophysics, and electroluminescent devices
No full textA simple design strategy for a new class of stable, vacuum-sublimable, and strongly emissive sky-blue neutral phosphorescent Re(I) phenanthroline complexes {Re(R2phen)(CO)3[CNB(C6F5)3]} is reported. These complexes show intense bluish green emission in CH2Cl2 solution with the highest emission quantum yield and bluest emission ever reported for the neutral Re(I) diimine complexes. In the solid state, they display sky-blue emission. The electroluminescent properties of devices containing these complexes have also been investigated
Behavior and ecotoxicity of manufactured nanomaterials in marine environment
No full textIn the last decade, the safety and risks of manufactured nanomaterials (MNMs) have been raised concerned in governments and scientists. Different reports focusing on the environmental hazard assessment and ecotoxicology of MNMs have been published. However, few of the reports are specially focus on the stability and ecotoxicity of MNMs in marine environment. It should be recognized that most industrial discharges are to estuarine or marine environments, and it is expected that the MNMs may follow the same fate. Therefore, the fate, behavior and toxicological effects of MNMs in marine environment, especially the estuary and coastal system, should not be neglected. We presented here the comparative behaviors of MNMs (such as TiO2 nanoparticles, etc.) in fresh and marine environment. The bioaccumulation and toxicity of MNMs to various marine organisms were also detected. The future needs in marine nanoecotoxicology were discussed in the end
Facile synthesis and photocatalytic disinfection of boron self-doped TiO2 nanosheets
No full textIn this study, a facile hydrothermal method was successfully developed to synthesize boron self-doped TiO2 nanosheets directly from TiB2 powders. XRD and TEM results suggested that the as-prepared TiO2 were pure anatase phase and showed a sheet morphology with reactive (001) facets. XPS analysis revealed the presence of boron as dopants by substituting oxygen atom in TiO2 nanosheets. The effect of HBF4 on TiO2 synthesis was also investigated. Photocatalytic disinfection experimental study implied that boron self-doped TiO2 exhibited better performance than P25 under visible light irradiation. The enhanced photocatalytic effect was ascribed to the nanosheet morphology with reactive (001) facets and self-doping of boron in TiO2
Time-motion analysis of elite male kickboxing competition
No full textThe objective of the study was to analyze the time structure of high-level kickboxing matches. A total of 45 combats from 2 male World Championships were monitored using a time-motion analysis system. The combat time structure (i.e., high-intensity activity [HIA], low-intensity activity [LIA], and referee breaks or pauses) during competition and weight divisions was determined and compared. Results indicated that the time structures were HIA: 2.2 +/- 1.2 seconds; LIA: 2.3 +/- 0.8 seconds; pauses: 5.4 +/- 4.3 seconds; and 3.4 +/- 1.2 seconds between 2 subsequent HIA. The fighting to nonfighting ratio was found to be 1:1. Moreover, the number of HIA and LIA and the time of LIA decreased in latter rounds (e.g., the average number of HIA was 27.1 +/- 7.1, 25.1 +/- 6.6, and 24.9 +/- 6.1, respectively, for rounds 1, 2, and 3), meanwhile the time and number of pauses increased (e.g., the average pause times were 12.8 +/- 11.4, 22.3 +/- 22.6, and 24.6 +/- 23.3 seconds, respectively, for rounds 1, 2, and 3). The activity times did not differ among weight categories. The present results confirm the intermittent nature of kickboxing competition and provide coaches with more information on how to structure training sessions to mimic the physical demands in competition
Comparing the physiological and perceptual responses of construction workers (bar benders and bar fixers) in a hot environment
No full textThis study aimed to (1) quantify the respective physical workloads of bar bending and fixing; and (2) compare the physiological and perceptual responses between bar benders and bar fixers. Field studies were conducted during the summer in Hong Kong from July 2011 to August 2011 over six construction sites. Synchronized physiological, perceptual, and environmental parameters were measured from construction rebar workers. The average duration of the 39 field measurements was 151.1 ± 22.4 min under hot environment (WBGT = 31.4 ± 2.2 °C), during which physiological, perceptual and environmental parameters were synchronized. Energy expenditure of overall rebar work, bar bending, and bar fixing were 2.57, 2.26 and 2.67 Kcal/min (179, 158 and 186 W), respectively. Bar fixing induced significantly higher physiological responses in heart rate (113.6 vs. 102.3 beat/min, p \u3c 0.05), oxygen consumption (9.53 vs. 7.14 ml/min/kg, p \u3c 0.05), and energy expenditure (2.67 vs. 2.26 Kcal/min, p \u3c 0.05) (186 vs. 158 W, p \u3c 0.05) as compared to bar bending. Perceptual response was higher in bar fixing but such difference was not statistically significant. Findings of this study enable the calculation of daily energy expenditure of rebar work
A factor−cluster approach to understanding Hong Kong hotel employees\u27 symptom-management-related coping behavior towards job stress
No full textJob stress is widespread within the hotel industry, given its people-orientation and long working hours. This study used a factor−cluster approach to investigate how hotel employees cope with job stress. Cluster analysis identified distinct groups within the sample, and the relationships between demographic factors and coping behavior were then examined. Exploratory qualitative in-depth interviews were used to develop an instrument for measuring job stress and coping behavior, after which a survey was conducted to discover the underlying dimensions and types of those behavior. One hundred and eighty-five staff from 15 hotels in Hong Kong responded to the questionnaire. Factor analysis identified four types of coping behavior: (1) organizational initiatives, (2) sharing with people, (3) personal behavior, and (4) emotional release. Several demographic factors showed significant correlations with some of these four types of behavior. Cluster analysis revealed three distinct groups: (1) aggressive reactors, (2) medium reactors, and (3) mild reactors. Aggressive reactors were found to score higher than mild reactors for all types of coping behavior. However, no significant correlations were found between the demographic variables and the three clusters. The implications of the study for hotel owners and managers are discussed
Production of extended self: integrating life experience in fashion design
No full textThis paper employed the conceptions of “extended self” (Belk, 1988) and expressivism (Taylor, 1989) to demonstrate how local fashion designers in post-colonial Hong Kong express their life experience and cultural identity through their designs. Through conducting long interviews (McCracken, 1988) with five local designers in Hong Kong our findings show that design collections have become an “extended self” for these individuals. The material representation that created by the individual become an inseparable self for the owner. The commercialization of these “extended selves” extends our current conception of self identity in marketing literature
How does enclosure influence environmental preferences? a cognitive study on urban public open spaces in Hong Kong
No full textOpen space can be stress alleviating and healing through the appropriate enclosure. Based on theories about environmental preferences and empirical studies on spatial enclosure, this study examined the relationship between environmental preference indicators and enclosure of urban public open spaces in Hong Kong. The preference indicators including four perceptual attributes and feedbacks on six feelings were evaluated together with the spatial enclosure of 178 subjects based on images of 26 single spaces selected in Hong Kong. All of the four perceptual attributes and five out of six feelings showed significant differences between different spatial enclosures. The results showed that subjects from Hong Kong tended to prefer more open spaces to enclosed ones. Through further interpretations, paths, visual connection with adjacent spaces, and a clear and simple spatial structure of enclosure seemed to influence subjects’ feelings and their preferences towards certain spaces. When spatial enclosure is somehow ambiguous, the space could still be preferred as long as the relationship between the single space and its adjacent spaces is clear. Design implications are then discussed for public space in high-rise high-density urban contexts