Períodos de interferência de erva-quente (Spermacoce atifolia) no crescimento inicial de eucalipto (Eucalyptus grandis)

The buttonweed (Spermacoce latifolia) is becoming a plant among the most current infesting eucalypts plantation in State of São Paulo due to the continual use of same herbicides and control methods. Owing this, this work aimed to evaluate the effects of periods of company and control of S. Iatifolia on the initial growth of Eucalyptus grandis, planted in winter and summer. Only one seedling of Eucalyptus was planted in amianthus cement box and submitted for crescent periods of company and control of S. Iatifolia (0, 20, 60 and 80 days in competition or not). The densities of plants of S. Iatifolia were 4 and 16 plants per m 2 (under winner and summer conditions). The experimental period was 100 days after the planting (DAP). The experimental design for both experiments was the completely randomized blocks (CRB) with ten treatments and four replicates. The results of plant high, stem diameter, dries weights and leaf area showed that the before interference period (BIP), whole period of prevention for interference (WPPI) and critical period of prevention for interference (CPPI) were 40, 60, and 60 DAR, respectively, under winner conditions. Under summer conditions, the WPPI and CPPI were 20, 80 and 20 to 80 DAR.

Neonatal inhalatory anesthetic exposure: Reproductive changes in male rats

We investigated the effects of an inhalatory anesthetic (ethyl ether) during the neonatal period of brain sexual differentiation on the later fertility and sexual behavior of male rats. Animals were exposed to ethyl ether immediately after birth. At adulthood, body weight, testes wet weight, and plasma testosterone levels were not affected; however, neonatal exposure to ether showed alterations on male fertility: a decrease in the number of spermatids and spermatozoa, an increase in the transit time of cauda epididymal spermatozoa and a decrease in daily sperm production. An alteration of sexual behavior was also observed: decreased male sexual behavior and appearance of homosexual behavior when the male rats were castrated and pretreated with exogenous estrogen. Probably, the ether delayed or reduced the testosterone peak of the sexual differentiation period, altering the processes of masculinization and defeminization of the hypothalamus. Our results indicate that perinatal exposure to ethyl ether during the critical period of male brain sexual differentiation, acting as endocrine disruptors, has a long-term effect on the fertility and sexual behavior of male rats, suggesting endocrine disruption through incomplete masculinization and defeminization of the central nervous system. © 2002 Elsevier B.V. All rights reserved.

Secretion of middle ear in infants - Occurrence, recurrence and related factors

Objective: The present study aimed at evaluating the occurrence and recurrence of middle ear effusion and possible associated factors in the first two years of life of 190 newborns and infants, participants in the interdisciplinary prevention, detection, and intervention program at the Clínica de Educação para Saúde of Universidade do Sagrado Coração, Methods: Newborns and infants were monthly submitted to anamneses, otoscopy, behavioral hearing assessment using sound instruments and pure tones (pediatric audiometry) and tympanometry. Results: The results revealed that 68.4% of infants presented one or more episodes of middle ear effusion during their two first years, with more recurrence among males. Peak occurrence was between four and 12 months of age and, the earlier the first episode, the higher the probability of recurrence. Greatest incidence was during May and August. It was found that, of the variables investigated, the period of exclusive breastfeeding actuated as a protector factor. With respect of risk factors, it was observed that passive smoking, gastro-esophageal reflux and respiratory allergy were related with the recurrences of effusion. Conclusion: Findings revealed the importance of periodic auditory follow-up for infants during their first two years of life, considered to be the critical period of auditory system maturation, during which sensory deprivation can be responsible for damage to the development of speech, language and other auditory abilities. Copyright © 2005 by Sociedade Brasileira de Pediatria.

Secreção na orelha média em lactentes ocorrência, recorrência e aspectos relacionados

Objective: The present study aimed at evaluating the occurrence and recurrence of middle ear effusion and possible associated factors in the first two years of life of 190 newborns and infants, participants in the interdisciplinary prevention, detection, and intervention program at the Clínica de Educação para Saúde of Universidade do Sagrado Coração. Methods: Newborns and infants were monthly submitted to anamneses, otoscopy, behavioral hearing assessment using sound instruments and pure tones (pediatric audiometry) and tympanometry. Results: The results revealed that 68.4% of infants presented one or more episodes of middle ear effusion during their two first years, with more recurrence among males. Peak occurrence was between four and 12 months of age and, the earlier the first episode, the higher the probability of recurrence. Greatest incidence was during May and August. It was found that, of the variables investigated, the period of exclusive breastfeeding actuated as a protector factor. With respect of risk factors, it was observed that passive smoking, gastro-esophageal reflux and respiratory allergy were related with the recurrences of effusion. Conclusion: Findings revealed the importance of periodic auditory follow-up for infants during their first two years of life, considered to be the critical period of auditory system maturation, during which sensory deprivation can be responsible for damage to the development of speech, language and other auditory abilities. © 2007 Sociedad Chilena de Pediatría.

Quantificação do interferon-tau durante o reconhecimento materno da gestação em fêmeas bovinas Bos taurus indicus

During the critical period of the maternal recognition, which occurs between days 15 and 19 of pregnancy, the conceptus must competently synthesize molecules capable of blocking the synthesis of prostaglandin F2α (PGF2α) and luteolysis. In cattle, the major macromolecule involved in suck blockage is the protein interferontau (IFN-τ). During the critical period, failures in the recognition of pregnancy determine embryonic mortality on up to 40% of inseminated cows. Data about IFN-τ in Bos taurus indicus are still scarce. Objective of this study was to quantitatively evaluate the presence of IFN-τ during the critical period for maternal recognition of pregnancy in uterine flushings obtained in vivo by Foley catheter (Days 14, 16 and 18 post estrus) or post-mortem (Day 18 post estrus). Multiparous, cyclic or pregnant zebu cows (Bos taurus indicus) on days 14, 16 and 18 post estrus were used for in vivo or post mortem uterine flushing collection. In both cases, a Ringer solution was used to wash the uterus of cows. Uterine flushings were concentrated by ultrafiltration and lyophilized. Proteins were separated by one-dimensional electrophoresis (SDS-PAGE) in a 15% polyacrilamide gel. Interferontau quantification in uterine flushings was performed by western blotting and densitometry. Non-specific protein bands were observed in both in vivo and post mortem uterine flushings. Interferon-tau was detected only in uterine flushings obtained from pregnant cows post-mortem (P<0.05). Optical density of protein bands was not affected by the day of the critical period, state (cyclic or pregnant) or interaction day x state. There was no effect of the conceptus weight or progesterone concentration on the day of uterine flushing collection in the optical density of the IFN-τ protein band. It was concluded that the detection and quantification of IFN-τ in the uterine environment of zebu cows, in these experimental?conditions, is only possible in uterine flushings obtained post-mortem.

Influéncia da adubação nitrogenada sobre a interferéncia de plantas daninhas em feijoeiro1

The competition between weeds and bean plants, especially because of nutrients in the environment, is extremely important to minimize potential losses of crop productivity. Thus, the aim of this work was to evaluate the effects of using nitrogen fertilization on the timing and extent of the period before interference (PAI), total period of interference (PTPI) and the critical period of interference control (PCPI) in bean cultivar 'Ruby'. The seeds were sown in the conventional system and the trial was conducted in two areas at the same time, in which the nitrogen fertilization was performed only in one of them. Each area received 14 treatments consisting of two groups: first, the crop was free of interference of weeds from emergence to 10, 20, 30, 40, 50, 60 and 70 days; and the second: the crop remained free of interference from sowing to the same periods described above. The experimental design was randomized blocks with four replications. Raphanus raphanistrum showed greater relative importance in the two areas, mainly due to the accumulation of dry mass, followed by Amaranthus deflexus. There was no difference in diversity and evenness of weed populations in response to the fertilization. In the area without N PAI occurred 18 days after emergence (DAE), and up to 24 DAE PTPI, resulting in PCPI 18 to 24 DAE, this area had 58% of reduction in crop yield. In the area where with nitrogen fertilization, PAI occurred at 38 DAE and PTPI occurred at 19 DAE. In this area there was 56% of reduction in crop yield. The nitrogen fertilization increased crop productivity and favored competitiveness in relation to weeds.

Piecewise linear perturbations of a linear center

This paper is mainly devoted to the study of the limit cycles that can bifurcate from a linear center using a piecewise linear perturbation in two zones. We consider the case when the two zones are separated by a straight line Σ and the singular point of the unperturbed system is in Σ. It is proved that the maximum number of limit cycles that can appear up to a seventh order perturbation is three. Moreover this upper bound is reached. This result confirms that these systems have more limit cycles than it was expected. Finally, center and isochronicity problems are also studied in systems which include a first order perturbation. For the latter systems it is also proved that, when the period function, defined in the period annulus of the center, is not monotone, then it has at most one critical period. Moreover this upper bound is also reached.

Períodos de interferência de uma comunidade infestante na cultura do milho em primeira e segunda safras

Pós-graduação em Agronomia (Agricultura) - FCA

Efeitos a longo-prazo do tratamento neonatal com glutamato-monossódico no dimorfismo sexual esquelético e secreção de leptina e corticosterona

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Kant e o fim da modernidade pré-crítica: os sonhos de um visionário

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O pensamento militar de León Trotsky e a formação do exército vermelho: 1918-1925

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A “Crônica Literária” de Medeiros e Albuquerque: resenhas e notícias literárias publicadas no vespertino A Notícia de 1897 a 1908

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação de pacientes com sequência de Robin no pós-operatório imediato após palatoplastia primário

Pós-graduação em Enfermagem (mestrado profissional) - FMB

Estudo fitossociológico e interferência das plantas daninhas na nutrição e produtividade do quiabeiro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do espaçamento na interferência das plantas daninhas na cultura do amendoim

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)