Reproductive biology of an endemic Physalaemus of the Brazilian Atlantic forest, and the trade-off between clutch and egg size in terrestrial breeders of the P. signifer group

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Territorial hypothesis predicts the trade-off between reproductive opportunities and parental care in three species of damselfishes (Pomacentridae: Actinopterygii)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A trade off between separation, detection and sustainability in liquid chromatographic fingerprinting

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Digging effort in leaf-cutting ant queens (Atta sexdens rubropilosa) and its effects on survival and colony growth during the claustral phase

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of visual information on optimal obstacle crossing

Human motion seems to be guided by some optimal principles. In general, it is assumed that human walking is generated with minimal energy consumption. However, in the presence of disturbances during gait, there is a trade-off between stability (avoiding a fall) and energy-consumption. This work analyses the obstacle-crossing with the leading foot. It was hypothesized that energy-saving mechanisms during obstacle-crossing are modulated by the requirement to avoid a fall using the available sensory information, particularly, by vision. A total of fourteen subjects, seven with no visual impairment and seven blind, walked along a 5 meter flat pathway with an obstacle of 0.26 m height located at 3 m from the starting point. The seven subjects with normal vision crossed the obstacle successfully 30 times in two conditions: blindfolded and with normal vision. The seven blind subjects did the same 30 times. The motion of the leading limb was recorded by video at 60 Hz. There were markers placed on the subject's hip, knee, ankle, rear foot, and forefoot. The motion data were filtered with a fourth order Butterworth filter with a cut-off frequency of 4 Hz. The following variables were calculated: horizontal distance between the leading foot and the obstacle at toe-off prior to (DHPO) and after (DHOP) crossing, minimal vertical height from the foot to the obstacle (DVPO), average step velocity (VELOm). The segmental energies were also calculated and the work consumed by the leading limb during the crossing obstacle was computed for each trial. A statistical analysis repeated-measures ANOVA was conducted on these dependent variables revealing significant differences between the vision and non-vision conditions in healthy subjects. In addition, there were no significant differences between the blind and people with vision blindfolded. These results indicate that vision is crucial to determine the optimal trade-off between energy consumption and avoiding a trip during obstacle crossing.

Stratified Sampling Applied to Estimation of the Volumetric Fraction of Alumina in Cast Metal Matrix Composites

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The evolution of jumping performance in anurans: morphological correlates and ecological implications

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The scent of stress: Pintado catfish differentially respond to chemical cues from stressed conspecifics

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Does attraction to frugivores or defense against pathogens shape fruit pulp composition?

Fruit traits evolve in response to an evolutionary triad between plants, seed dispersers, and antagonists that consume fruits but do not disperse seeds. The defense trade-off hypothesis predicts that the composition of nutrients and of secondary compounds in fruit pulp is shaped by a trade-off between defense against antagonists and attraction to seed dispersers. The removal rate model of this hypothesis predicts a negative relationship between nutrients and secondary compounds, whereas the toxin-titration model predicts a positive relationship. To test these alternative models, we evaluated whether the contents of nutrients and secondary compounds can be used to predict fruit removal by mutualists and pathogens in 14 bird-dispersed plants on a subtropical island in São Paulo state, southeastern Brazil. We selected eight to ten individuals of each species and prevented fruit removal by covering four branches with a net and left fruits on four other branches available to both, vertebrate fruit consumers and pathogens. The persistence of ripe fruits was drastically different among species for bagged and open fruits, and all fruit species persisted longer when protected against seed dispersers. We found that those fruits that are quickly removed by vertebrates are nutrient-rich, but although the attack rate of pathogens is also high, these fruits have low contents of quantitative defenses such as tannins and phenols. Thus, we suggest that the fruit removal rate by seed dispersers is the primary factor selecting the levels of fruit defense. Likewise, nutrient-poor fruits have low removal of seed dispersers and low probability of attack by pathogens. These species retain ripe fruits in an intact condition for a prolonged period because they are highly defended by secondary compounds, which reduce overall attractiveness. However, this strategy might be advantageous for plants that depend on rare or unreliable dispersers.

A simple graphical model of small mammal succession after fire in the Brazilian cerrado

We studied the succession of small mammal species after fire in the cerrado (Neotropical savanna) of Central Brazil. Populations of small mammals were sampled with live-trapping techniques in a series of nine sites of different successional age, ranging from 1 to 26 years after fire. Ten species of small mammals were captured through all the seral stages of succession. Species richness ranged from two to seven species by seral stage. The species were arranged in different groups with respect to abundance along the succession: the first was composed of early successional species that peaked <2 years after fire (Calomys callosus, C. tener, Thalpomys cerradensis, Mus musculus, Thylamys velutinus); the second occurred or peaked 2-3 years after fire (Necromys lasiurus, Gracilinanus sp., Oryzomys scoth). Gracilinanus agilis peaked in the last seral stage. Species richness of small mammals showed an abrupt decrease from an average of four species immediately after fire to two species 5-26 years after the last fire. We propose a simple graphical model to explain the pattern of species richness of small mammals after fire in the cerrado. This model assumes that the occurrence of species of small mammals is determined by habitat selection behavior by each species along a habitat gradient. The habitat gradient is defined as the ratio of cover of herbaceous to woody vegetation. The replacement of species results from a trade-off in habitat requirements for the two habitat variables.

Aggressive Behavior and Performance in the Tegu Lizard Tupinambis merianae

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Alternative fidelity measure between quantum states

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Processo de trabalho e eficiência produtiva: Smith, Marx, Taylor e Lênin

A partir de reflexão sobre uma hipotética transição do capitalismo em sua natureza manufatureira ao socialismo, procura-se deixar marcada a razão pela qual, seguindo a proposta de Marx, essa transição exige que a produção se realize sob a égide da maquinaria. Consegue-se, como parte dessa reflexão, identificar, para o caso da manufatura, um trade-off entre eficiência produtiva e humanização das atividades de trabalho. Procura-se esclarecer que, dada a natureza do taylorismo-fordismo como reinvenção da manufatura, o exercício de início especulativo passa a ter sentido histórico. Busca-se argumentar que a ampla assimilação do taylorismo-fordismo pela experiência de implantação do socialismo na União Soviética a aprisionou ao mencionado trade-off , fazendo com que a primeira experiência de superação do capitalismo se impregnasse perversamente da mediocridade imanente ao taylorismo-fordismo. Finalmente, são feitos rápidos comentários acerca dos desdobramentos da recente automação de base microeletrônica sobre a natureza de um projeto socialista.

Análise de decisão multicritério na localização de usinas termoelétricas utilizando SIG

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)