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Effect of different recovery durations between bouts in 3-a-side games on youth soccer players\u27 physiological responses and technical activities
No full textThe aim of this study was to investigate the effects of the length of recovery durations between bouts in 4x4min 3-a-side small-sided games (SSG) on time-motion analysis, technical actions and physiological responses of players.Twelve young soccer players participated in 4 different 3-a-side games in which the recovery durations between bouts were different (R1: 1 min, R2: 2 min, R3: 3 min, and R4: 4 min). Heart rate (HR), total distance covered in different speed zones, and technical performance were monitored during all SSGs, whereas the rating of perceived exertion (RPE, CR-10) and venous blood lactate were determined at the end of the last bout of each SSG.Results showed that SSGs-R1 induced higher %HRreserve and lower successful passes (vs. R3 and R4 conditions, P\u3c0.05), lower total passes (vs. R4 conditions, P\u3c0.05), and greater distance covered in walking zone (0-6.9 km.h⁻¹) (vs. other 3 conditions, P\u3c0.05). In addition, during the SSG-R3 players covered greater distances in high-intensity running zone (\u3e18 km.h-1), performed more tackles (vs. R1 condition, P\u3c0.05) and had more ball contacts (vs. R1 and R2 conditions, P\u3c0.05).According to these results, it is thought that R1 and R2 are suitable for inducing higher physiological responses, while R3 and R4 are more appropriate for training aim to improve technical skills in 4x4min 3-a-side SSGs among young soccer players. These findings provide evidence for coaches to justify the selection of recovery duration between bouts in 3-a-side SSGs among young soccer players
General network analysis of national soccer teams in FIFA World Cup 2014
No full textThis study analyzed the network characteristics of successful and unsuccessful national teams that participated in FIFA World Cup 2014. The relationship between the variables of overall team performance and the network characteristics measured on the basis of the passes between teammates was also investigated. A dataset of 37,864 passes between teammates in 64 soccer matches enabled the study on network structure and team performance of 32 national soccer teams. Our results showed significant differences in the dependent variables of network density (F4,123 = 2.72; p = 0.03; η 2 p = 0.04; small effect size) and total links (F4,123 = 2.73; p = 0.03; η 2 p = 0.04; small effect size) between the teams that reached the later stages of the tournament. Goals scored presented a small positive correlation with total links (r = 0.24; p = 0.001), network density (r = 0.24; p = 0.001), and clustering coefficient (r = 0.17; p \u3e 0.050). High levels of goals scored were associated with high levels of total links, network density, and clustering coefficient. This study showed that successful teams have a high level of network density, total links, and clustering coefficient. Thus, large values of connectivity between teammates are associated with better overall team performance
Blessing in disguise or bluffing in this guide: CDA on Chinese language education policy for Hong Kong ethnic minority students
No full textEfficacy of a transtheoretical model intervention to improve college students\u27 physical activity engagement: a pilot randomized controlled trial
No full textRecent reports have indicated the severity of physical inactivity. Few previous interventions have adopted randomized controlled trials (RCT) for the promotion of college students’ physical activity (PA) in Hong Kong. The aim of this pilot study is to test the efficacy of a Transtheoretical Model (TTM)-based intervention to enhance college students’ PA behaviour. Twenty-five healthy, sedentary student volunteers (16 male and 9 females) were recruited and randomly allocated to the TTM-based experimental group (n=12) or the control group (n=13). The treatment intervention group underwent fitness training and TTM-based counselling, while the control group received fitness training only. The fitness training for both groups lasted for 4 weekly sessions at a campus fitness facility. All participants wore a pedometer. Daily pedometer counts were recorded into the PA log as a direct-measured PA engagement. Direct-measured fitness outcomes and self-reported health outcome measurements were assessed before and after the 4-week intervention. Data were analysed to distinguish the intervention group from the control group. The initial results of this pilot study could be said to support the TTM-based behaviour intervention for PA promotion in Hong Kong college settings. Randomization was found to be successful and the instrumentation was effective with certain limitations. Due to the small and varied group size, the effectiveness of the intervention seemed inconclusive and too negligible to declare. Finally, based on discussion of the results and findings, recommendations have been drawn to inform the upcoming study at community level and future PA intervention practices
A new class of safe, potent, and specific P-gp modulator: flavonoid dimer FD18 reverses P-gp-mediated multidrug resistance in human breast xenograft in vivo
No full textFlavonoid dimer FD18 is a new class of dimeric P-gp modulator that can reverse cancer drug resistance. FD18 is a potent (EC50 = 148 nM for paclitaxel), safe (selective index = 574), and selective P-glycoprotein (P-gp) modulator. FD18 can modulate multidrug resistance toward paclitaxel, vinblastine, vincristine, doxorubicin, daunorubicin, and mitoxantrone in human breast cancer LCC6MDR in vitro. FD18 (1 μM) can revert chemosensitivity of LCC6MDR back to parental LCC6 level. FD18 was 11- to 46-fold more potent than verapamil. FD18 (1 μM) can increase accumulation of doxorubicin by 2.7-fold, daunorubicin (2.1-fold), and rhodamine 123 (5.2-fold) in LCC6MDR. FD18 inhibited P-gp-mediated doxorubicin efflux and has no effect on influx. FD18 at 1 μM did not affect the protein expression level of P-gp. Pharmacokinetics studies indicated that intraperitoneal administration of 45 mg/kg FD18 was enough to maintain a plasma level above EC50 (148 nM) for more than 600 min. Toxicity studies with FD18 (90 mg/kg, i.p. for 12 times in 22 days) with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) revealed no obvious toxicity or death in mice. In vivo efficacy studies indicated that FD18 (45 mg/kg, i.p. for 12 times in 22 days) together with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) resulted in a 46% reduction in LCC6MDR xenograft volume (n = 11; 648 ± 84 mm3) compared to paclitaxel control (n = 8; 1201 ± 118 mm3). There were no animal deaths or significant drop in body weight and vital organ wet weight. FD18 can increase paclitaxel accumulation in LCC6MDR xenograft by 1.8- to 2.2-fold. The present study suggests that FD18 represents a new class of safe and potent P-gp modulator in vivo
Relaxation effect of abacavir on rat basilar arteries
No full textBackground: The use of abacavir has been linked with increased cardiovascular risk in patients with human immunodeficiency virus infection; however, the mechanism involved remains unclear. We hypothesize that abacavir may impair endothelial function. In addition, based on the structural similarity between abacavir and adenosine, we propose that abacavir may affect vascular contractility through endogenous adenosine release or adenosine receptors in blood vessels.
Methods: The relaxation effect of abacavir on rat basilar arteries was studied using the myograph technique. Cyclic GMP and AMP levels were measured by immunoassay. The effects of abacavir on nucleoside transporters were studied using radiolabeled nucleoside uptake experiments. Ecto-5′ nucleotidase activity was determined by measuring the generation of inorganic phosphate using adenosine monophosphate as the substrate.
Results: Abacavir induced the relaxation of rat basilar arteries in a concentration-dependent manner. This relaxation was abolished when endothelium was removed. In addition, the relaxation was diminished by the nitric oxide synthase inhibitor, L-NAME, the guanylyl cyclase inhibitor, ODQ, and the protein kinase G inhibitor, KT5820. Abacavir also increased the cGMP level in rat basilar arteries. Abacavir-induced relaxation was also abolished by adenosine A2 receptor blockers. However, abacavir had no effect on ecto-5’ nucleotidase and nucleoside transporters. Short-term and long-term treatment of abacavir did not affect acetylcholine-induced relaxation in rat basilar arteries.
Conclusion: Abacavir induces acute endothelium-dependent relaxation of rat basilar arteries, probably through the activation of adenosine A2 receptors in endothelial cells, which subsequently leads to the release of nitric oxide, resulting in activation of the cyclic guanosine monophosphate/protein kinase G-dependent pathway in vascular smooth muscle cells. It is speculated that abacavir-induced cardiovascular risk may not be related to endothelial dysfunction as abacavir does not impair relaxation of blood vessels. The most likely explanation of increased cardiovascular risk may be increased platelet aggregation as suggested by other studies
Ultrasonic disruption of fungal mycelia for efficient recovery of polysaccharide: protein complexes from viscous fermentation broth of a medicinal fungus
No full textHigh-intensity ultrasound (US) was applied to facilitate the extraction of intracellular and extracellular polysaccharide–protein complexes (PSPs) from the viscous mycelial fermentation broth of a medicinal fungus Cordyceps sinensis Cs-HK1. The US treatment caused the disruption of fungal mycelia, a dramatic reduction of the apparent broth viscosity, and the release of intracellular products into the liquid medium. The degree of mycelium disruption and the rate of intracellular product release were dependent on US power intensity, treatment period and biomass concentration of broth. The extraction or release kinetics of total water-soluble products and PSPs (yield Y versus time t) under the effect of US was fitted closely to the Elovich model Y=Yo+Y1 lnt and parabolic model Y=Yo+Y1t½, respectively. Another interesting effect of the US treatment was a notable increase in the antioxidant cytoprotective activity of PSP against H2O2 induced cell death
Effect of habitat traits on tree structure and growth in private gardens
No full textContext: Urban domestic gardens (UDG) provide an interesting landscape ecology theme with conservation and biodiversity applications.
Objectives: Effects of habitat traits on tree species composition, spatial distribution and growth performance were studied in private UDG in Hong Kong.
Methods: Five groups of tree-habitat variables were assessed: species-count per garden, tree-count per garden, lot-frontage width, garden depth, and tree-position in garden. Tree structural damage and growth condition were evaluated by visual tree-assessment techniques.
Results: The results recorded 1501 trees representing 72 species distributed in 261 gardens, with heavy bias towards exotic species (81.9 %) and exotic trees (91.1 %). The top-five species contributed 45 % of relative abundance, with higher spatial-occurrence and aggregation indices. Cluster analysis classified habitats into three groups based on species similarity. Correspondence analysis (CA) identified three distinct habitats types: good (cluster A), moderate (cluster B), poor (cluster C). Species distribution in CA ordination space was demarcated by structural damage and overall health condition. Nine species fell under the moderate–severe structural damage group, with four in cluster C and another four in clusters A and B. Some 41 species had poor and very poor overall condition, with seven species in cluster A and 14 in cluster C. Species groups were evaluated to inform a species selection strategy.
Conclusion: Species adoption by homeowners is molded by habitat traits and joint operation of collective–extrinsic and individualistic–intrinsic influences which have prevented arboreal homogenization and generated spatial differentiation. Measures should address the serious biodiversity gap induced by landscape fashion, nursery-industry supply, and inappropriate species choice
Centipeda minima (Ebushicao) extract inhibits PI3K-Akt-mTOR signaling in nasopharyngeal carcinoma CNE-1 cells
No full textBackground: Centipeda minima (Ebushicao) has been used for the treatment of various diseases, such as nasal allergies, rhinitis and sinusitis, nasopharyngeal carcinoma, cough, and headache. This study aims to investigate the anticancer activities of Centipeda minima ethanol extracts (CME) against nasopharyngeal carcinoma cell CNE-1 and their underlying mechanism.
Methods: CNE-1 cells were treated with different concentrations (15–50 μg/mL) of CME for different time intervals (24, 48, and 72 h). Cytotoxicity of CME was determined by MTT assay. Cell morphological changes were observed by fluorescence microscopy after HO 33258 staining. Cell cycle status was evaluated by flow cytometry following propidium iodide staining. Apoptosis was detected by flow cytometry following annexin V-FITC/PI staining. The levels of apoptosis-associated and PI3K-Akt-mTOR signaling related proteins were measured by western blotting analysis.
Results: CME (15–50 μg/mL) significantly inhibited the proliferation of CNE-1 in a dose- and time-dependent manner (P = 0.026 for 15 μg/mL, P \u3c 0.001 for 25, 30, 40, and 50 μg/mL, respectively); the IC50 values (μg/mL) were 41.57 ± 0.17, 30.34 ± 0.06 and 24.98 ± 0.08 for 24, 48 and 72 h treatments, respectively. Significant morphological changes of CNE-1 cells displaying apoptosis were observed after CME treatment. CME showed low cytotoxicity toward normal LO2 cells. CNE-1 cells were arrested in the G2/M phase while treated with 15, 25, 40 μg/mL of CME, respectively (P = 0.032, P = 0.0053, P \u3c 0.001). CME (15, 25, 40 μg/mL) down-regulated Bcl-2 expression (P = 0.032, P = 0.0074, P \u3c 0.001), and up-regulated Bax (P = 0.026, P = 0.0056, P \u3c 0.001) with activation of caspase-3, caspase-8, caspase-9, and PARP observed in CNE-1 cells (P = 0.015, P = 0.0067, P \u3c 0.001 for caspase 3; P = 0.210, 0.028, \u3c 0.001 for caspase 8; P = 0.152, 0.082, 0.0080 for caspase 9; P = 0.265, 0.0072, \u3c 0.001 for PARP). CME suppressed the activation of the PI3K-AKT-mTOR pathway (P = 0.03, 0.0007, 0.004, 0.006, 0.022 for p-PI3K, p-Akt-Ser473, p-Akt-Thr308, p-mTOR-Ser2448, p-mTOR-Ser2481, respectively after 40 μg/mL of CME treated for 24 h).
Conclusion: CME inhibited the proliferation of CNE-1 cells and activation of the PI3K-AKT-mTOR signaling pathway
Rapport and its managerial implications in FM service outsourcing relationships
No full textIn Hong Kong, client companies tend not to renew contracts with relationship partners and may change facilities management (FM) service providers on a frequent basis. This phenomenon is common in the FM industry. Inspired by the phenomenon of changing service providers, this study sheds light on a social relations perspective in outsourcing relationships and aims to investigate the factors that affect FM service outsourcing relationships. Open interviews with 20 FM managers were conducted, and the interview results were analysed with content analysis and coding methods. The empirical findings were interpreted on two levels. First, FM managers believe that rapport is an influential factor that affects FM service outsourcing relationships. Second, the courses in which the interviewees explain the manifestation of rapport and its significance reveal that common goals, shared values, trust, openness, and coordination are the factors that not only nurture the formation of rapport, but also have significant influences on social relations in the process of outsourcing. A framework has been developed to describe the conceptual relationships found in the empirical findings from the interviews. Eight guidelines have been outlined to indicate the managerial implications of this study