153 resultados para Infertile couples
Resumo:
Structural, electrochemical and spectroscopic data of a new dinuclear copper(II) complex with (+/-)-2-(p- methoxyphenoxy) propionic acid are reported. The complex {tetra-mu-[(+/-)-2-(p-methoxyphenoxy)propionato-O,O']-bis( aqua) dicopper(II)} crystallizes in the monoclinic system, space group P2(1)/n with a = 14.149(1) angstrom, b = 7.495(1) angstrom, c = 19.827(1) angstrom, beta = 90.62(1) and Z = 4. X-ray diffraction data show that the two copper(II) ions are held together through four carboxylate bridges, coordinated as equatorial ligands in square pyramidal geometry. The coordination sphere around each copper ion is completed by two water molecules as axial ligands. Thermogravimetric data are consistent with such results. The ligand has an L' type shape due to the angle formed by the beta-carbon of the propionic chain and the linked p-methoxyphenoxy group. This conformation contributes to the occurrence of a peculiar structure of the complex. The complex retains its dinuclear nature when dissolved in acetonitrile, but it decomposes into the corresponding mononuclear species if dissolved in ethanol, according to the EPR measurements. Further, cyclic voltammograms of the complex in acetonitrile show that the dinuclear species maintains the same structure, in agreement with the EPR data in this solvent. The voltammogram shows two irreversible reduction waves at E-pc = -0.73 and -1.04 V vs. Ag/AgCl assigned to the Cu(II)/ Cu(I) and Cu(I)/Cu degrees redox couples, respectively, and two successive oxidation waves at E-pa = -0.01 and +1.41 V vs. Ag/AgCl, assigned to the Cu degrees/Cu(I) and Cu( I)/Cu( II) redox couples, respectively, in addition to the oxidation waves of the carboxylate ligand.
Resumo:
Several studies have been made about biology, predatory capacity, and food consumption to crisopids species, trying to get informations to use in Integrated Pest Management. Raising insects in laboratory for many generations could cause blood relation problems, even annihilate the insect mass production. In this way, the objective of this work was to determine the consumption and the weight gain to Chrysoperla externa larvae from two populations and different laboratory generations, founded by 1, 5, 10, 15 and 20 couples. By the result it was possible to conclude that larvae food consumption was higher in populations founded by greater number of couples, and it is not verified variation among populations and generations.
Resumo:
The objective of this work was to evaluate the biology of Orius insidiosus fed on eggs of Plutella xylostella and Anagasta kuehniella. The eggs used were obtained from the Laboratorio de Biologia e Criacao de Insetos, Departamento de Fitossanidade, FCAV/UNESP. The experiment was carried out with a total of 50 12-to-24-hour-old O. insidiosus nymphs, 1 per Petri dish (50 replications). P. xylostella or A. kuehniella eggs were places into each Petri dish daily, along with a small cotton pad moistened with distilled water. The evaluations were carried out daily. The adults were separated in couples, and placed in Petri dishes. The following biological aspects were evaluated: duration, survival rate and consumption of the nymph instars and of the nymph period; longevity of males and females; consumption per day and adult longevity; eggs per day; female fecundity; egg viability; embryonic period; preoviposition period, oviposition period, post-oviposition period. The fertility life table parameters were also evaluated. The predator O. insidiosus did not present significant differences for its biological characteristics, when feeding on P. xylostella and A. kuehniella eggs, however it showed improved fertility life table parameters when fedo n eggs of P. xylostella, suggesting the possibility of using these eggs in the mass rearing of this insect.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
The kinetics of the hexacyanoferrate(III)-N,N′-dimethyl-4,4′-bipyridinium radical (MV+) reaction was studied by a laser flash photolysis technique. The radical was generated, in the presence of Fe(CN)6 3-, by quenching the excited state *Ru(bpy)3 2+ with MV2+. The second-order rate constant for the Fe(CN)6 3--MV+ reaction is (7.6 ± 0.5) × 109 M-1 s-1 at 23°C and ionic strength 0.10 M. Comparison with the rate constants calculated for the diffusion-controlled reaction (4.7 × 109 M-1 s-1) and the activation-controlled reaction (5.2 × 1012 M-1 s-1, on the basis of self-exchange rate constants of 8.0 × 105 M-1 s-1 and 1.9 × 104 M-1 s-1 for the MV2+/+ and Fe(CN)6 3-/4- couples, respectively) leads to the conclusion that the Fe(CN)6 3--MV+ reaction is diffusion controlled. The rate constant for the Fe(CN)6-MV2+ reaction, calculated from the rate constant for the Fe(CN)6 3--MV+ reaction and the appropriate equilibrium constant, is 2.4 × 10-5 M-1 s-1 at 23°C and ionic strength 0.10 M. Microscopic reversibility considerations require that the Fe(CN)6 4--MV2+ reaction be controlled by the dissociation of the successor complex Fe(CN)6 3-|MV+. The thermal and optical electron transfers in the ion pair Fe(CN)6 4-|MV2+ and in related systems are analyzed and discussed. © 1982 American Chemical Society.
Resumo:
It is well known that radiation causes mutation, and that mutations are generally deleterious. They can lead to disease, malformation and death. It is further known that we live in a radioactive world. The air, the soil, the water, the food, all are somewhat radioactive. Natural radiation is not uniformly distributed throughout the earth's crust. There are some areas, especially in Brazil and India, where the levels of background radiation are several times higher than generally obtains. We have undertaken a specially prepared house-to-house genetic-epidemiologic, retrospective survey in a large Brazilian area with levels of natural radiation ranging from 7 (normal) to 133 (high) micro-roentgens per hour. In all, 24 different localities were surveyed during a period of 10 months by a trained team of nurses and social assistants. Our total sample consists of more than 8,000 couples who have had almost 44,000 pregnancy terminations. Our results do not disprove that natural radiation is one of the causes of socalled spontaneous mutations. They only show that, under the conditions of this study, no detectable effect on abortion was found. Our results also attest to the importance of extraneous variables in the analysis of morbidity and mortality data.
Resumo:
We quantize a generalized version of the Schwinger model, where the two chiral sectors couples with different strengths to the U(1) gauge field. Starting from a theory which includes a generalized Wess-Zumino term, we obtain the equal time commutation relation for physical fields, both the singular and non-singular cases are considered. The photon propagators are also computed in their gauge dependent and invariant versions. © 1995 Springer-Verlag.
Resumo:
We studied the diet and food resources partitioning by fishes from the Itaúna stream, municipality of Itatinga, Southeastern Brazil. Eighteen species of fish were collected, being Microlepidogaster sp., Hypostomus sp., Astyanax sp., Phalloceros caudimaculatus and Heptapterus sp. the most frequent and abundant ones. Regarding diet, the majority of the species were observed to be insectivorous (61%), while insectivorous-herbivorous and periphyton feeders ranked 22 and 17%, respectively. The food overlap analysis revealed many cases of similarity between the diets. For most cases, however, a detailed analysis of food items and spatial distribution of the species showed differences between the couples under analysis which points toward a reduction in competition for food.
Resumo:
A comparative study between the metric and the teleparallel descriptions of gravitation is made for the case of a scalar field. In contrast to the current belief that only spin matter could detect the teleparallel geometry, scalar matter being able to feel the metric geometry only, we show that a scalar field is able not only to feel anyone of these geometries, but also to produce torsion. Furthermore, both descriptions are found to be completely equivalent, which means that in fact, besides coupling to curvature, a scalar field couples also to torsion.
Resumo:
We support the idea that the baryon, B with mass MB, couples to its current with a coupling λ2 B ∼ 0.71 M6 B from an analysis of magnetic moment sum rules. And we find a sum rule among the experimental magnetic moments which is independent of the parameters of QCDSR. © 1998 Elsevier Science B.V. All rights reserved.
Resumo:
We consider a two-dimensional integrable and conformally invariant field theory possessing two Dirac spinors and three scalar fields. The interaction couples bilinear terms in the spinors to exponentials of the scalars. Its integrability properties are based on the sl(2) affine Kac-Moody algebra, and it is a simple example of the so-called conformal affine Toda theories coupled to matter fields. We show, using bosonization techniques, that the classical equivalence between a U(1) Noether current and the topological current holds true at the quantum level, and then leads to a bag model like mechanism for the confinement of the spinor fields inside the solitons. By bosonizing the spinors we show that the theory decouples into a sine-Gordon model and free scalars. We construct the two-soliton solutions and show that their interactions lead to the same time delays as those for the sine-Gordon solitons. The model provides a good laboratory to test duality ideas in the context of the equivalence between the sine-Gordon and Thirring theories. © 2000 Elsevier Science B.V. All rights reserved.
Resumo:
The Brazilian population, presents genes for abnormal hemoglobins with variable frequencies, which are influenced by the founding racial groups. Thus, the detection of carriers of the genetic alterations is important for public health, since they represent sources of new beterozygotes and possible homozygotes. The control of the hemoglobin pathologies has been possible by means of genetic counseling and early diagnosis. The clinical follow-up of the homozygotes and the orientation of the beterozygotes and especially the couples at risk represent a more effective mode of acting to avoid the birth of children who are carriers of a genetic disease, that is frequently lethal. For these reasons this work had as its objectives: to evaluate the importance of testing in pregnant women for the detection of hemoglobin pathologies with the purpose of investigating the prevalence, attaining prevention, a familial study and awareness; for the positive cases such as couples at risk, orient as to appropriate medical attendance; and to evaluate the response to the program. Of the total of 696 pregnant women analysed, 10.7% revealed hemoglobin pathologies with the following rates: alpha Thalassemia 6.75%; Hb AS 2.01%; beta minor Thalassemia 1.29%; Hb AC 0.28%; Hb AJ 0.14%; Hb AS/Alpha Thalassemia 0.14% and P.H.H.F. 0.14%. The high rates of hemoglobin pathologies encountered in the population of pregnant women studied shows the necessity of the implantation of tests for these abnormalities in the pre-natal routine, since in this period the mothers are more apt to be preoccupied with their own health and that of their babies and, however earlier diagnosed the alterations in the hemoglobins, better and more adequate will be the orientations given the couple.
Resumo:
Phenotypic sexual dimorphism seems to be rare in the Ramphastidae family, except in Pteroglossus viridis and in the genus Selenidera. Many breeders of wild birds believe that specimens of Ramphastos toco can be sexed using bill characteristics. In this study, various discriminant phenotypic variables were analyzed in birds which were sexed cytogenetically. Fifty-one specimens of R. toco and 20 R. dicolorus were studied. The statistically significant parameters which served to distinguish the sex in these species were the length of the culmen and tomium, length of the lower corneous beak and the cloaca. Using these parameters, capitive bird breeders can determine sex of R. toco specimens by phenotypic analysis and form breeding couples more quickly.
Resumo:
This study aims to compare a psychological evaluation test to classical psychoanalysis in infertile women. Two hundred women were submitted to the Psychological Evaluation Test (PET). The sum of the scores for the responses ranged from 15 to 60 points, with scores ≥ 30 points being defined as psycho-emotional maladjustment (cut-off point: median + 25%). For comparison, a psychologist submitted the patients to a psychological examination simultaneously, who was unaware of the PET results. From the 200 patients, 66 (33%) presented a test with ≥ 30 points (psycho-emotional maladjustment) and 134 (67%) a test with < 30 points (normal). Upon psychological examination, 105 (52.5%) presented an abnormal evaluation and 95 (47.5%) a normal evaluation. For the PET, statistical analysis showed 82% efficiency, 62% sensitivity, 98% positive predictive value, 99% specificity, 70% negative predictive value, likelihood ratio for a positive test result 62, and likelihood ratio for negative test result 0.38. The PET proved to be a useful clinical instrument, being of help for the selection of patients with psychological needs induced by infertility.
Resumo:
Purpose: to evaluate the incidence and types of major congenital malformations (MCM) in liveborn children conceived by intracytoplasmic sperm injection (ICSI). Methods: a total of 680 liveborn children resulted from 511 couples submitted to ICSI from January, 1999 to December, 2002. Data collection of the children was performed through standardized questionnaire and clinical examination. Of the 511 couples, 366 had been contacted for a sampling of 371 gestations. Of the 680 liveborn, 520 had been evaluated, 250 of them (48.1%) through questionnaire and 270 (51.9%) through questionnaire and physical examination. Two hundred and fifty children were from singleton pregnancies and 270 from multiple pregnancies. Malformations were classified according to the 10th revision of the International Statistical Classification of Diseases and Related Health. Only MCM were analyzed in this study. The incidence of MCM was compared with that of the general population obtained by the Latin American Collaborative Study of Congenital Malformations. The statistical analysis was performed by the χ 2 test (level of significance p<0.05). Results: of the 520 children, 15 presented MCM, resulting in an incidence of 2.9%. There was no difference in relation to the control group (p>0.05), which showed 2.6% incidence of MCM. The most frequent malformations were of cardiac origin (four isolated and two associated), corresponding to 40% of the total. The other types of MCM were: renal (three), neural tube (two), skull (one), cleft lip (one), genital (one), Down syndrome (associated with cardiac malformations) (two), and musculoskeletal (one). Six MCM occurred in children from singleton pregnancies and nine in children from multiple pregnancies. Conclusion: the liveborn children conceived by ICSI presented incidence of major congenital malformations (2.9%) near to the expected for the general population (2.6%). However, to establish the risks of MCM with precision it is necessary to continue the evaluation of the children conceived by ICSI.