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281.
Sajitha GR Jose R Andrews A Ajantha KG Augustine P Augusti KT 《Indian journal of clinical biochemistry : IJCB》2010,25(3):280-288
Daily feeding of drinking water containing lead acetate (160 mg/l) or 10% alcohol by volume or a combination of both to rats
for a month produced certain deleterious effects through oxidative stress. Both heavy metal lead and alcohol are capable of
doing such damages. The deleterious alterations observed were in the parameters of blood, serum and tissues, viz; Hb, Pb,
proteins, lipids, lipid per oxidation, Vitamins C and E levels and enzyme activities of AST, ALT, and catalase. Simultaneous
feeding of either of the two antioxidants garlic oil (GO) and vitamin E at equal doses of 100 mg/kg/day, to the rats counteracted
the deleterious effects of the above two chemicals significantly. The maximum damage was brought about by feeding of drinking
water containing both lead acetate and alcohol. The protective effects of GO and Vitamin E were not significantly different.
The mechanism of actions of the Vitamin E and GO is probably due to their efficiency as detoxifying agents and antioxidants,
to scavenging free radicals as well as an independent action of GO on the removal of lead salt as lead sulfide. 相似文献
282.
Martin Halvey David ValletDavid Hannah Yue FengJoemon M. Jose 《Information processing & management》2010
There are a number of multimedia tasks and environments that can be collaborative in nature and involve contributions from more than one individual. Examples of such tasks include organising photographs or videos from multiple people from a large event, students working together to complete a class project, or artists and/or animators working on a production. Despite this, current state of the art applications that have been created to assist in multimedia search and organisation focus on a single user searching alone and do not take into consideration the collaborative nature of a large number of multimedia tasks. The limited work in collaborative search for multimedia applications has concentrated mostly on synchronous, and quite often co-located, collaboration between persons. However, these collaborative scenarios are not always practical or feasible. In order to overcome these shortcomings we have created an innovative system for online video search, which provides mechanisms for groups of users to collaborate both asynchronously and remotely on video search tasks. In order to evaluate our system an user evaluation was conducted. This evaluation simulated multiple conditions and scenarios for collaboration, varying on awareness, division of labour, sense making and persistence. The outcome of this evaluation demonstrates the benefit and usability of our system for asynchronous and remote collaboration between users. In addition the results of this evaluation provide a comparison between implicit and explicit collaboration in the same search system. 相似文献
283.
This article presents conceptual navigation and NavCon, an architecture that implements this navigation in World Wide Web pages. NavCon architecture makes use of ontology as metadata to contextualize user search for information. Based on ontologies, NavCon automatically inserts conceptual links in Web pages. By using these links, the user may navigate in a graph representing ontology concepts and their relationships. By browsing this graph, it is possible to reach documents associated with the user desired ontology concept. This Web navigation supported by ontology concepts we call conceptual navigation. Conceptual navigation is a technique to browse Web sites within a context. The context filters relevant retrieved information. The context also drives user navigation through paths that meet his needs. A company may implement conceptual navigation to improve user search for information in a knowledge management environment. We suggest that the use of an ontology to conduct navigation in an Intranet may help the user to have a better understanding about the knowledge structure of the company. 相似文献
284.
Vicente J. Beltrán-Carrillo Alejandro Jiménez-Loaisa Miriam Alarcón-López Jose L. L. Elvira 《Journal of sports sciences》2019,37(7):788-794
The purpose of this study was to examine the validity of a highly popular pedometer application (Samsung Health). Sixteen adults (28.8 ± 8.9 years of age) wore two Samsung smartphone models, Samsung Galaxy Core Prime (SGCP) and Samsung Galaxy S4 (SGS4), at three body locations (waist, arm, and hand) while walking and running over a 50-m test. All trials were recorded using a video as a gold standard measure of step counts. Results indicated that the validity of Samsung Health varied depending on the smartphone model, its body location, and the type of gait (walking and running). Samsung Health showed acceptable validity when the SGCP was located on the hand (Bias = ?8.3%; RMSE = 5.6), and especially on the arm (Bias = ?7.2%; RMSE = 4.9) while running, and when the SGS4 was located on the arm (Bias = ?7.5%; RMSE = 5.4), and especially on the waist (Bias = 5.4%; RMSE = 3.7) while walking. Samsung Health only showed good validity when the SGS4 was located on the arm (Bias = 2.9%; RMSE = 3.6), and especially on the hand (Bias = 0.5%; RMSE = 2.5) while running. This application showed unacceptable validity in the remaining options. 相似文献
285.
Pablo Molina-Garcia Jairo H Migueles Cristina Cadenas-Sanchez Irene Esteban-Cornejo Jose Mora-Gonzalez Maria Rodriguez-Ayllon 《Journal of sports sciences》2019,37(8):878-885
This study aimed to investigate the independent and combined associations between several fatness indicators and fitness components with functional movement quality in overweight/obese children. A total of 56 children (33 girls, aged 8–12) classified as overweight/obese according to the World Obesity Federation standard cut points, participated in this study. Participants underwent assessments of fatness [body mass index (BMI), waist circumference, and bioelectrical impedance measures], fitness [1 repetition maximum bench and leg press, and ALPHA test battery], and functional movement quality [4 tests from Functional Movement Screen TM (FMS)]. All fatness outcomes, except waist circumference, were negatively associated with total FMS score, after controlling for cardiorespiratory fitness. Cardiorespiratory fitness, lower limbs muscle strength, and speed-agility were positively associated with the total FMS score, regardless of BMI. Our results suggest that children with greater fatness indicators demonstrate lower functional movement quality independently of their fitness level, whereas children with better fitness level (i.e. cardiorespiratory fitness, lower limbs muscular strength, and speed-agility) demonstrate greater functional movement quality independently of their fatness level. However, children´s weight status seems to be more determinant than their fitness level in terms of functional movement quality, whereas being fit seems to moderately attenuate the negative influence of fatness. 相似文献
286.
Vicente Lizondo Jordi Caplliure-Llopis Dolores Escrivá Jose Enrique De La Rubia 《European Journal of Sport Science》2019,19(6):850-859
The objective of this study was to analyse bone quality parameters of football players with intellectual disability (ID) participating in adapted competitive football. Sixty-seven male football players with ID were studied: 22 with Down syndrome (DS) and 45 without DS. The average age was 26 years (range: 16 ? 50 years). A group of 25 age-matched sedentary individuals with ID (11 DS and 14 non-DS) and another group of 20 healthy participants of the same age group not involved in competitive football were comparatively analysed. There were no differences in the bone quality parameters when the healthy sedentary individuals were compared with both the sedentary and the football players with ID. However, the speed of sound (SOS), T-score, and estimated bone mineral density (BMD) were of higher values in the football players with ID than in the sedentary ID group (p?0.05). On comparing the football players with non-DS ID with the sedentary non-DS individuals, significant differences were noted in SOS (p?0.01), T-scores (p?0.01), and estimated BMD (p?0.01). Four of the 45 non-DS (8.9%) and none of the football players with DS had T-scores less than ?1.5. Two of the 14 sedentary non-DS participants (14.3%) had T-scores indicating osteoporosis. In summary, the ID population actively involved in football showed higher values of bone mass parameters than their sedentary ID and healthy peers. The participants with non-DS ID showed a higher prevalence of osteoporosis than the football players with DS. Participation in sports seems to prevent bone loss in individuals with ID. 相似文献
287.
Iván Clavel San Emeterio Jorge García-Unanue Eliseo Iglesias-Soler Jose Luis Felipe Leonor Gallardo 《European Journal of Sport Science》2019,19(2):217-224
Research question: The increase of physical exercise in fitness centres has turned these facilities in important active lifestyle promoters. However, only between 30% and 60% of subscribers still linked to the sports centre after a year. The aim of this study is to design a model to predict the drop out in fitness centres. Research methods: Monthly data corresponding to the actual behaviour of 14,522 members of three sport centres in Spain were recorded over the course of one year. In order to calculate the likelihood of drop out, logistic regressions were used to create predictive models for each centre. Results and findings: It was possible to predict abandonment of users of sport centres from their historical behaviour, although the predictive models obtained for each centre were not completely coincident. The effectiveness of the models was around 70%. Implications: The analysis of users’ behaviour in a fitness centre can allow to avoid the drop out and therefore the abandonment of physical activity. Segmenting the customers based on the likelihood of drop out may be useful for improving the effectiveness of the strategies of loyalty and for optimizing the organization of human and material resources. 相似文献
288.
Juan Ignacio Pulido-Fernández Marcelino Sánchez-Rivero 《Journal of Cultural Economics》2010,34(2):111-129
As a result of globalization, the widespread use of ICTs, and advances in transport infrastructure, tourism destinations have
to confront an increasingly competitive setting. When to this one adds the saturation of some of the original markets, the
consolidation of traditional coastal destinations, and changes in client preferences and habits, it is not surprising that
cultural tourism is being seen as having considerable growth potential over the next few years. In this context, policy-makers
have been striving to better understand the cultural tourism market by attempting to segment their clients so as to adapt
their offer to the client’s needs and leave the client satisfied with the experience. Unfortunately, most studies on cultural
tourism segmentation have been purely psychographic. While this can help to explain attitudes, it fails to identify, access,
and quantify segments, and is of little use for implementing specific strategies. The aim of the present work was to study
the influence of socioeconomic and demographic variables (age, academic level, expenditure on tourism, inter alia) on the predisposition to choose cultural tourism (the “culturophile tourist”). To this end, we have developed a novel methodological
approach and applied it to the results of a survey conducted by Andalusia’s Middle Towns Initiative. The approach uses the
latent variables resulting from a latent class analysis to estimate log-linear models. 相似文献
289.
Various studies have built models, using aggregate box-office data, to predict the contribution of a motion picture’s features
to its theatrical demand. But such an approach fails to represent the heterogeneous influence of movie features on demographic
groups and is unable to assist market-segmentation decisions. We propose and illustrate a new approach for modeling the appeal
of movie features to market segments via the use of appropriate individual-specific data and canonical correlation analysis.
Specifically, through demographically detailed movie-attendance data available in Spain, we build a model of how movie features
influence the demographic composition of audiences. Via a canonical correlation analysis, we identify four dimensions underlying
the relationships between several movie features (country of origin, genre, objectionable content, stars, promotional effort,
and critical evaluations) and audience demographics (gender, age range, presence of children, education, social class, and
size of municipality). These dimensions represent the strong pairings between four moviegoer demographic profiles and four
movie-feature profiles. Our approach can potentially aid in segmentation and green-lighting decisions by matching movie features
with the most relevant segment-specific preferences. 相似文献
290.
Miguel Ángel Gómez Crespo Juan Ignacio Pozo 《International Journal of Science Education》2013,35(11):1325-1343
This paper analyses the representations held by adolescents and university students in relation to the mechanism for explaining changes in matter (changes of state, dissolutions, expansions and chemical reactions) in terms of the kinetic theory. The answers to a questionnaire were analysed by considering the proportion of correct answers and the use of alternative conceptions. The results show that understanding of explanatory mechanisms of changes in matter is affected by age and instruction level and content of the problem. The main conception that competes with the kinetic model is the attribution to the particles of the changes observed, at a macroscopic level. This is more evident in changes of state and expansions than in other changes. This confusion results from a failure to differentiate properly between the represented reality and the model that represents it. In conclusion, analysis has shown once more students' difficulties in going beyond apparent reality or integrating the data obtained from it into the scientific models they learn at school. 相似文献