966 resultados para behavior survey


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper studies behavior in experiments with a linear voluntary contributions mechanism for public goods conducted in Japan, the Netherlands, Spain and the USA. The same experimental design was used in the four countries. Our 'contribution function' design allows us to obtain a view of subjects' behavior from two complementary points of view. If yields information about situations where, in purely pecuniary terms, it is a dominant strategy to contribute all the endowment and about situations where it is a dominant strategy to contribute nothing. Our results show, first, that differences in behavior across countries are minor. We find that when people play "the same game" they behave similarly. Second, for all four countries our data are inconsistent with the explanation that subjects contribute only out of confusion. A common cooperative motivation is needed to explain the date.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Es presenten els resultats d’una enquesta sobre l’ús de revistes electròniques realitzada al professorat de les universitats que formen el Consorci de Biblioteques Universitàries de Catalunya (CBUC). Els resultats mostren un elevat grau de coneixement de la col·lecció de revistes electròniques entre el personal docent i investigador i una creixent preferència pel format electrònic en detriment de l’imprès. L’alt grau de coneixement i d’ús dels títols electrònics, i la preferència per aquest suport, comporten una elevada valoració de la col·lecció de revistes electròniques. Al mateix temps, la major part dels usuaris preveu un increment de l’ús dels títols electrònics durant els propers anys. Els resultats també confirmen la importància de la disciplina i de l’edat com a factors explicatius de l’ús de les revistes electròniques.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We study how personal relations affect performance in organizations. In the experimental game we use a manager has to assign different degrees of decision power to two employees. These two employees then have to make distributive decisions which affect themselves and the manager. Our focus is on the effects on managers' assignment of decision power and on employees' distributive decisions of one of the employees and the manager knowing each other personally. Our evidence shows that managers tend to favor employees that they personally know and that these employees tend, more than other employees, to favor the manager in their distributive decisions. However, this behavior does not affect the performance of the employees that do not know the manager. All these effects are independent of whether the employees that know the manager are more or less productive than those who do not know the manager. The results shed light on discrimination and nepotism and its consequences for the performance of family firms and other organizations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present notes are intended to present a detailed review of the existing results in dissipative kinetic theory which make use of the contraction properties of two main families of probability metrics: optimal mass transport and Fourier-based metrics. The first part of the notes is devoted to a self-consistent summary and presentation of the properties of both probability metrics, including new aspects on the relationships between them and other metrics of wide use in probability theory. These results are of independent interest with potential use in other contexts in Partial Differential Equations and Probability Theory. The second part of the notes makes a different presentation of the asymptotic behavior of Inelastic Maxwell Models than the one presented in the literature and it shows a new example of application: particle's bath heating. We show how starting from the contraction properties in probability metrics, one can deduce the existence, uniqueness and asymptotic stability in classical spaces. A global strategy with this aim is set up and applied in two dissipative models.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We study a model where agents, located in a social network, decide whether to exert effort or not in experimenting with a new technology (or acquiring a new skill, innovating, etc.). We assume that agents have strong incentives to free ride on their neighbors' effort decisions. In the static version of the model efforts are chosen simultaneously. In equilibrium, agents exerting effort are never connected with each other and all other agents are connected with at least one agent exerting effort. We propose a mean-field dynamics in which agents choose in each period the best response to the last period's decisions of their neighbors. We characterize the equilibrium of such a dynamics and show how the pattern of free riders in the network depends on properties of the connectivity distribution.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A survey of the plarnorbid fauna in the Brazilian states of the Amazonian river basin revealed the occurence of 14 species, 8 of the genus Biomphalaria, 4 of Drepanotrema, 1 of Antillorbis and 1 of Plesiophysa, besides a naturalized puopulation of Helisoma duryi at Santa Rosa, municipality of Formosa, state of Goiás. The following is the distribution of the species by genera, in decreasing order of frequency (number of localities in parenthesis): 1. Biomphalaria straminea (50): Acre, Amazonas, Distrito Federal, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Pará and Roraima; 2. B. occidentalis (30): Acre, Amazonas, Mato Grosso and Mato Grosso do Sul; 3. B. schrammi (22); Distrito Federal, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul and Pará; 4. B. amazonica (14): Acre, Amazonas and Rondônia; 5. B. glabrata (13): Distrito Federal, Goiás, Maranhão and Pará; 6. B. peregrina (4): Distrito Federal, Goiás and Mato Grosso do Sul; 7. B. tenagophila (2): Distrito Federal and Goiás; 8. B. oligoza (2): Mato Grosso do Sul; 9. Drepanotrema lucidium (72): Acre, Amapá, Amazonas, Distrito Federal, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Pará, Rondônia and Roraima; 10. D. anatinum (41): Acre, Amazonas, Distrito Federal, Goiás, Maranhão, Mato Grosso do Sul, Pará, Rondônia and Roraima; 11. D. depressissimum (19): Acre, Amazonas, Distrito Federal, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul and Pará; 12. D. cimex (15): Acre, Amazonas, Distrito Federal, Goiás, Mato Grosso, Mato Grosso do Sul and Pará; 13. Antillorbis nordestensis (3): Distrito Federal, Maranhão and Pará; 14. Plesiophysa ornata (1): Goiás. B. glabrata is responsibel for transmission of schistosomiasis mansoni in northeastern Pará, northern Marnhão and central Goiás including the Distrito Fedreal. B. tenagophila, although susceptible to experimental infection with Schistosoma mansoni, has not been found naturally infected so far in the area. B. straminea has been incriminated as...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A study of the courship and copulation behaviour of Panstrongylus megistus was carried out in the laboratory. fifty-five newly-fed virgin couples were used. Experiments were performed during the day (9:00 to 12:00 a.m.) and at night (7:00 to 10:00 p.m). Behaviour was recorded by direct observation and was found to consist of the following sequence of behavioral patterns: the male approached the female and jumped on her or mounted her; he took on a dorsolateral position and immobilized the female dorsally and ventrally with his three pairs of legs; the male genital was placed below those of the female; the paramers of the male immobilized the female's genitals; copulation started. The couple joined by the iniciative of the male. The female could be receptive and accept copulation, or nonreceptive and reject the male. Copulation occurred more often on the occasion of the first attempt by the male. Duration of copulation was X = 29.3 ± 9.3 min (CV = 83%). No behavioral differences were observed couples tested during the day or at night.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Healthy lifestyle including sufficient physical activity may mitigate or prevent adverse long-term effects of childhood cancer. We described daily physical activities and sports in childhood cancer survivors and controls, and assessed determinants of both activity patterns. METHODOLOGY/PRINCIPAL FINDINGS: The Swiss Childhood Cancer Survivor Study is a questionnaire survey including all children diagnosed with cancer 1976-2003 at age 0-15 years, registered in the Swiss Childhood Cancer Registry, who survived ≥5 years and reached adulthood (≥20 years). Controls came from the population-based Swiss Health Survey. We compared the two populations and determined risk factors for both outcomes in separate multivariable logistic regression models. The sample included 1058 survivors and 5593 controls (response rates 78% and 66%). Sufficient daily physical activities were reported by 52% (n = 521) of survivors and 37% (n = 2069) of controls (p<0.001). In contrast, 62% (n = 640) of survivors and 65% (n = 3635) of controls reported engaging in sports (p = 0.067). Risk factors for insufficient daily activities in both populations were: older age (OR for ≥35 years: 1.5, 95CI 1.2-2.0), female gender (OR 1.6, 95CI 1.3-1.9), French/Italian Speaking (OR 1.4, 95CI 1.1-1.7), and higher education (OR for university education: 2.0, 95CI 1.5-2.6). Risk factors for no sports were: being a survivor (OR 1.3, 95CI 1.1-1.6), older age (OR for ≥35 years: 1.4, 95CI 1.1-1.8), migration background (OR 1.5, 95CI 1.3-1.8), French/Italian speaking (OR 1.4, 95CI 1.2-1.7), lower education (OR for compulsory schooling only: 1.6, 95CI 1.2-2.2), being married (OR 1.7, 95CI 1.5-2.0), having children (OR 1.3, 95CI 1.4-1.9), obesity (OR 2.4, 95CI 1.7-3.3), and smoking (OR 1.7, 95CI 1.5-2.1). Type of diagnosis was only associated with sports. CONCLUSIONS/SIGNIFICANCE: Physical activity levels in survivors were lower than recommended, but comparable to controls and mainly determined by socio-demographic and cultural factors. Strategies to improve physical activity levels could be similar as for the general population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To determine in influence of feeding, lighting and time of day on the copulating behavior of Panstrongylus megistus, 480 insect pairs were divided into four groups of 120 each and tested in the following respective situations: without food deprivation (F.D.), with five days of F.D., with ten days of F.D., and with 20 days of F. D. The tests were performed between 9:00 a.m. to 12:00a.m. and 7:00 p.m. to 10:00 p.m., with light (700-1400 lux) and in the dark (1.4-2.8 lux) and behavior was recorded by the time sampling technique. Mating spped (MS) and duration of copulation (DC) were also calculated for each situation. The maximum frequency of copulation was observed after five days of F.D., at night, in the dark (n = 16), and the minimum was observed for recently-fed pairs, at night, with light (n = 4). Males approached females more often than females approached males. MS was lowest in pairs with twenty days of F.D., at night, with light (X = 23.0 ± 16.0 minutes), and highest in recently-fed pairs, during the day, with light (X = 2.9 ± 2.5 minutes). DC was shortest in recently-fed insects, during the day, in the dark (X = 23.5 ± 6.7 minutes), and longest in recently-fed animals, at night, in the dark (X = 38.3 ± 6.9 minutes).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A study of the effect of mating in the fecundity and fertility of females of P. megistus fed on pigeon blood every 14 days, was carried out in the laboratory. Two groups were constituted: I - females which mated only once; II - females which stayed always with the males. Only 56.7% of group I females laid fertile eggs, while as much as 90% of group II females laid fertile eggs. The duration of the fertile oviposition was greater in the females which stayed always with the males. Some females of this group were able to mate up to seven times throughout their life-span. This fact render useless sterile males in the control of these insects. It is suggested that the components of pigeon's blood used for feeding the triatomines could have an influence upon the fecundity and fertility of the female sof the two groups.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Using three columns of different depths (1.10m, 8.40m and 10.40m), we investigated the possibility of Biomphalaria glabrata moving towards deep regions. In the 1.10m column, we noted that locomotion can occur in two manners: 1) when the foot is in contact with the substrate: a) sliding descent; b) sliding ascent; c) creeping descent; d) creeping ascent, 2) when the foot is not in contact with the substrate: a) sudden descent without emission of air bules; b) sudden descent with emission of air bules; c) sudden ascent. In the 8.40m column containing food on the bottom (experimental group), the snails remained longer at this depth when compared to those of the group which received no food (control). The sliding behavior was characteristic of locomotion occurring at 0 to 1m both in upward and downward directions. Creeping behavior was typical for the ascent of the snails that reached deeper levels. When the snails were creeping, the shell remained hanging as if it were heavier, a fact that may have been due to water entering the pulmonary chamber. In the 10.40m column, the snails slid downward to a depth of 4m or descended suddenly all the way to the bottom. Ascent occurred by creeping from the bottom to the surface. In the 8.40m and 10.40m columns, copulation, feeding and oviposition occurred at the deepest levels.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper reviews the literature on clinical signs such as imitation behavior, grasp reaction, manipulation of tools, utilization behavior, environmental dependency, hyperlexia, hypergraphia and echolalia. Some aspects of this semiology are of special interest because they refer to essential notions such as free-will and autonomy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A laboratory study was conducted on the fecundity, fertility and life span of Panstrongylus megistus pairs and on the fecundity and life span of P. megistus virgin females submitted to starvation after the last moulting. Of the mated females, 22.2% laid eggs, 4.4% of which were fertile. Females resisted starvation more than males. Of the starved virgin females, only 10% laid eggs, with a low egg-laying rate (0.47) per female. Resistance to starvation was lower in virgin than in mated females.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Attempts have been made to characterize two strains of Leishmania that became infective to golden hamsters only after they had been maintained for several years in a chemically defined culture medium. Observations were made on the growth rates of promastigotes in vitro, course of infection in hamsters, morphology of amastigotes, and electrophoretic mobility patterns of eight isoenzymes. Information was obtained about the buoyant densities of n-DNA and k-DNA, and one strain was tested against monoclonal antibodies. The identity of both strains remains obscure.