35 resultados para Serodiscordant couples
Resumo:
In the biological study, the development of the biological cycle of the insect under different feeding conditions was evaluated. The insects were fed on either mouse blood (c) or pigeon blood (p) using two types of rearing techniques (individual or group) at 28(graus) C and 90% relative humidity (which is equivalent to their natural environment). A fifth cycle studied, was fed on mouse blood reared on group, and mantained at laboratory environmental temperature. In the five cycles analyzed, it was found that groups on mouse blood at near natural conditions developed more rapidly (between 60 and 73 days) and had a lower rate of mortality (16.66%). The daily handling and changes in environment, of the individually reared insects, for observation of biological characteristics (no. and duration of bloodmeal, defecation and first fed of each stage) had a negative influence. None of the individuals fed on mouse or pigeon blood reached adult hood. It was found that the longevity and the fertility rate were significantly superior on couples maintained individually on mouse blood. These males had an average lifespan of 110,26 days and the females had an average lifespan of 104,46 days. The average number of eggs laid by each female was 21,26. Four couples kept in groups (five couples in each group) under the same condition, the longevity for males was 51,86 days and for females was 81,06 days. An average of 10,5 eggs were laid by each female. However, the percentage of fertile eggs was higher in couples kept in groups (72.15%) than in the individual couples (57.68%).
Resumo:
We tested the attraction of Panstrongylus megistus odor under laboratory conditons, between males and females of this species and by individuals of each sex on recently fed virgin couples. We employed a system of choice boxes both with or without aeration over the stimuli in the tested situations. We also observed a clear trend among the insects to remain in the central box where they had been placed in the beginning of the tests.
Resumo:
The factors affecting the sexual behaviour of Panstrongylus megistus were studied under laboratory conditions. A general description of mating behaviour is presented for this species. The effect of the time elapsed after the first imaginal feeding on the mating frequency, the motivation of males to mate and the rejection behaviour by females, were analyzed. We also determined the number of copulas accepted by females of this species. Finally, the possible existence of a sexual chemical signal promoting male aggregation around mating couples was evaluated. Results showed that mating frequency increased with the time elapsed since the first adult meal. Despite the number of male copulatory attempts did not change as a function of time, the rejection behaviour of females became gradually less frequent. Females rejected mating by means of body flattening on the substrate, abdominal movements, evasion or stridulation. After a single copula, females did not usually accept to mate again. Neither male nor female aggregation around mating couples was observed, suggesting the absence of a sexual assembling pheromone in P. megistus.
Resumo:
Therapeutic failure of benznidazole (BZ) is widely documented in Chagas disease and has been primarily associated with variations in the drug susceptibility of Trypanosoma cruzi strains. In humans, therapeutic success has been assessed by the negativation of anti-T. cruzi antibodies, a process that may take up to 10 years. A protocol for early screening of the drug resistance of infective strains would be valuable for orienting physicians towards alternative therapies, with a combination of existing drugs or new anti-T. cruzi agents. We developed a procedure that couples the isolation of parasites by haemoculture with quantification of BZ susceptibility in the resultant epimastigote forms. BZ activity was standardized with reference strains, which showed IC50 to BZ between 7.6-32 µM. The assay was then applied to isolates from seven chronic patients prior to administration of BZ therapy. The IC50 of the strains varied from 15.6 ± 3-51.4 ± 1 µM. Comparison of BZ susceptibility of the pre-treatment isolates of patients considered cured by several criteria and of non-cured patients indicates that the assay does not predict therapeutic outcome. A two-fold increase in BZ resistance in the post-treatment isolates of two patients was verified. Based on the profile of nine microsatellite loci, sub-population selection in non-cured patients was ruled out.
Resumo:
The degree of reproductive isolation between Meccus phyllosomus and the remaining five species of the genus Meccus, as well as between Meccus bassolsae and Meccus pallidipennis, Meccus longipennis and Meccus picturatus, was examined. Fertility and the segregation of morphological characteristics were examined in two generations of hybrids from crosses between these species. The percentage of couples with offspring (fertile) was high in the vast majority of sets of crosses, with the exception of that between ♀M. phyllosomus and ♂Meccus mazzottii. In sets of crosses involving M. bassolsae specimens, no first-generation (F1) individuals were morphologically similar to M. bassolsae, but instead shared the morphology of the other parental species. A similar phenomenon was observed in most sets of crosses involving M. phyllosomus. These results indicated that different degrees of reproductive isolation exist among the species of Meccus involved in this study. The biological evidence obtained in this study does not support the proposal that M. bassolsae is a full species. It could indicate that, on the contrary, it should be considered a subspecies of a single polytypic species. The biological evidence does support the proposal that M. phyllosomus is a full species.
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Estimates of genetic susceptibility to leprosy were made in the past from observational reports in familial settings using descriptive epidemiologic data. Risk of conjugal transmission of leprosy (from one spouse to another) has been estimated between 1-10% and is thought to occur in 3-5% of spouses exposed to untreated lepromatous disease in the partner. Risk of secondary transmission is presumed higher in other family members than for the conjugal partner. This belief has become dogma to many leprologists who may no longer know the basis for this estimation. This article reviews the historic epidemiologic descriptions of risk for leprosy transmission in married couples compared to other family members. Although uncommon, conjugal leprosy occurs and at higher rates in populations with traditional familial intermarriage and consanguinity.
Resumo:
ABSTRACT A phenomenon closely linked to changes in social, economic, and cultural context is growing and growing as the years go by and attracting the attention of researchers for the development of studies involving both the individual and the organizational field. Named as "dual career family", this phenomenon emphasizes a joint move from a husband and wife (a couple) in the family sphere and in the development of both careers. Thus, in order to know how these relationships are being established, this study set out to investigate what are the determining factors that compose the dual career phenomenon in the Brazilian context. The research involved 340 participants, all former students of a public university, married or living in a marital status. The results allowed to feature, through descriptive statistics, the profile of dual career couples in the Brazilian scene and check what are the types of dual career in the country. We obtained five types of dual career: coordinated familistic, conventional familistic, coordinated careerist, conventional careerist and acrobat.
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Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae). Studies on Ceratitis capitata, a world fruit pest, can aid the implementation of control programs by determining the plants with higher vulnerability to attacks and plants able to sustain their population in areas of fly distribution. The objective of the present study was to evaluate the influence of eight tropical fruits on the following biological and behavioral parameters of C. capitata: emergence percentage, life cycle duration, adult size, egg production, longevity, fecundity, egg viability, and oviposition acceptance. The fruits tested were: acerola (Malpighia glabra L.), cashew (Anacardium occidentale L.), star fruit (Averrhoa carambola L.), guava (Psidium guajava L.), soursop (Annona muricata L.), yellow mombin (Spondias mombin L.), Malay apple (Syzygium malaccense L.), and umbu (Spondias tuberosa L.). The biological parameters were obtained by rearing the recently hatched larvae on each of the fruit kinds. Acceptance of fruits for oviposition experiment was assessed using no-choice tests, as couples were exposed to two pieces of the same fruit. The best performances were obtained with guava, soursop, and star fruit. Larvae reared on cashew and acerola fruits had regular performances. No adults emerged from yellow mombin, Malay apple, or umbu. Fruit species did not affect adult longevity, female fecundity, or egg viability. Guava, soursop, and acerola were preferred for oviposition, followed by star fruit, Malay apple, cashew, and yellow mombin. Oviposition did not occur on umbu. In general, fruits with better larval development were also more accepted for oviposition.
Resumo:
Biotic potential and reprodutcive parameters of Spodoptera eridania (Stoll) (Lepidoptera, Noctuidae) in the laboratory: This study aimed to evaluate the biotic potential and reproductive parameters of Spodoptera eridania (Stoll, 1782) under controlled conditions (25 ± 1ºC, 70 ± 10% RH and 14 hour photophase). The longevity, pre-, post- and oviposition periods, fecundity and fertility of 15 couples was evaluated. The longevity of females (10.80 days) was not significantly higher than those of males (9.27 days). The mean durations of the pre, post and oviposition periods were 2.067, 0.600 and 8.133 days, respectively. The mean fecundity per female was 1,398 eggs and the mean fertility was 1,367.50 larvae. On average, females copulated 1.133 times. A strong positive correlation was observed between the number of mating and fecundity (r = 0.881, P <0.001). However a strong negative correlation was observed between the number of copulations and the duration of the pre-oviposition period (r = -0.826, P = 0.002) and longevity (r = -0.823, P = 0.001). The biotic potential of S. eridania was estimated at 1.894 x 10(25) individuals/female/year. The net reproductive rate (Ro) was 560.531 times per generation and the mean generation time (T) was 35.807 days. The intrinsic rate of increase (rm) was 0.177, with a finite rate of increase (l) of 1.193, per week
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The objective of this work was to improve the mass rearing technique of Euschistus heros in laboratory. Nymphs and adults were reared at densities 100, 200, 300 and 400 eggs per Petri dish (9 cm diameter), and at 50, 100, 150 and 200 couples per rearing cages (900 mL), respectively. Survival rate of immature stages and survivorship and reproduction of adults were determinated. Survivorship of nymph to adult was the highest (89%) at density 100 eggs per dish. Adult survivorship was independent of density, and 100 couples per cage were the best to improve quality of the produced progeny. In these conditions, fecundity was 160.8±9.28 eggs per female, and a total of 8,950±456 eggs per cage per month was produced. Two hundred couples per cage showed a negative effect on reproduction, which decreased to 65%. With this technique, a colony of 35 cages with 100 couples per cage yields about 313.3 thousands eggs per month, which is enough to supply the egg parasitoid Telenomus podisi to colonize about 35 ha of soybean field.
Resumo:
The objective of this work was to evaluate the oviposition preference of Diatraea saccharalis and the effect of ten sugarcane cultivars on larval development. Oviposition preference was assessed under greenhouse conditions by three releases of couples of moths, with subsequent counting of egg masses and eggs per plant. In order to evaluate the effect of the cultivars on larval development, each plant was infected with about 150 eggs, and, 29 days later, the total number of internodes, number of bored internodes, number of life forms found, larval and pupal weight and length, and the width of larval head capsule were evaluated. The cultivars IACSP94-2101 and IACSP96-2042, the least preferred by D. saccharalis for oviposition, and IACSP94-2094, the most unfavorable for larvae entrance and development, show resistance to the pest.
Resumo:
The objective of this work was to evaluate the development, survival, reproductive capacity, and longevity of the Asian ladybug Harmonia axyridis in comparison with Cycloneda sanguinea and Hippodamia convergens. Coccinellid larvae and adults were fed daily with Schizaphis graminum. Ten couples of each species were isolated for evaluation of the adult phase. The duration of the larval stage of H. axyridis is the longest (10.2 days) and its adults are the heaviest (29.7 mg) compared with C. sanguinea and H. convergens. The three species showed similar percentages of survival during the developmental stages. An average of 82% of C. sanguinea, H. axyridis, and H. convergens larvae reached adulthood, which indicates that temperature (25°C) and the offered prey are favorable to coccinellid development. Harmonia axyridis produces a higher total number of eggs per female (1,029.2) than the other evaluated species. However, H. axyridis, which lives for an average of 147.2 days, does not show a significantly greater longevity than C. sanguinea (87.2 days) and H. convergens (134.3 days).
Resumo:
Coriolis force is an effect which arises in rotating reference frames such as the Earth. This force influences large oceanic motions, atmospheric inertial circles, horizontal and vertical deviations in moving bodies. The Foucault's pendulum is another special case about the Coriolis force influence on macroscopic processes. This pendulum is an example of how experimental sciences can be essential for philosophical and social changes, since it was crucial to prove the Earth's rotation. The Coriolis force has an important role also at microscopic level; it couples vibrational and rotational molecular motions and this fact has consequences in spectroscopic and energetic molecular processes. These points are discussed in this paper.
Resumo:
The [Ru3O(Ac)6(py)2(CH3OH)]+ cluster provides an effective electrocatalytic species for the oxidation of methanol under mild conditions. This complex exhibits characteristic electrochemical waves at -1.02, 0.15 and 1.18 V, associated with the Ru3III,II,II/Ru3III,III,II/Ru 3III,III,III /Ru3IV,III,III successive redox couples, respectively. Above 1.7 V, formation of two RuIV centers enhances the 2-electron oxidation of the methanol ligand yielding formaldehyde, in agreement with the theoretical evolution of the HOMO levels as a function of the oxidation states. This work illustrates an important strategy to improve the efficiency of the oxidation catalysis, by using a multicentered redox catalyst and accessing its multiple higher oxidation states.
Resumo:
Two simple and sensitive spectrophotometric methods (M1 and M2) for the determination of mosapride in pure and in pharmaceutical preparations are described. These methods are based on the interaction of diazotized mosapride (MSP) couples with chromotropic acid (CTA) [M1] in alkaline medium and diphenylamine (DPA) [M2] in acidic medium. The resulting azo-dyes exhibit maximum absorption at 560 nm and at 540 nm for methods M1 and M2, respectively. All variables were studied in order to optimize the reaction conditions. No interferences were observed from excipients, and the validity of the each method was tested against reference method.