Resposta do abacaxizeiro 'Vitória' a doses de nitrogênio em solos de tabuleiros costeiros da Paraíba

Informations about fertilization and mineral nutrition of the new fusariosis-resistant pineapple cultivars are still scarce, despite the importance of this crop. The purpose of this study was to evaluate the effect of increasing doses of N on fruit yield and quality of the pineapple cultivar 'Vitoria' grown on a 'Humiluvico Espodossolo' in the region of Tabuleiros Costeiros, in the state of Paraiba. The experiment was arranged in a randomized block design, using five N doses (100, 200, 300, 500 and 600 kg ha(-1)N, as urea) applied 60, 180 and 270 days after planting (dap) with three replications. The following variables were evaluated: length and fresh matter of the 'D' leaf; contents of N, P and K in the portions with and without chlorophyll, 300 and 420 dap; average weight, yield, physical properties (fruit weight, length and medium diameter; crown weight and length) and chemical properties (pH, soluble solids -SS, titrable acidity - AT, and the SS/AT ratio) of the fruits at harvest. Increasing N doses linearly increased length and fresh matter of the 'D' leaf and N content and decrease both P and K contents of the chlorophyll portion 300 dap, but did not affect nutrient contents 420 dap; in the chlorophyll-free portion. Increasing N doses, also, led to an increase in K contents 320 dap, but to reductions 420 dap. Individual fruit weight and total yield increased with increasing N doses, as maximum values of 1.0 kg and 37.9 t ha(-1) were estimated at doses of 409.0 and 439.0 kg ha(-1) N, respectively. The N doses did not affect the fruit quality properties, which were compatible with the characteristics described for this cultivar.

Impact of lameness on broiler well-being

Various degrees of lameness were compared among male broilers ranging in age from 28 to 49 d that had been randomly selected from a commercial farm. Gait scores were given to the broilers while they walked on a force measurement platform system, and the force exerted by their feet was measured and compared in 2 distinct conditions: with and without administration of an analgesic. Postmortem femoral degenerative lesions were observed, and the femur strength in response to a compression load was measured and compared. Results showed a difference in the peak vertical forces of the right and left feet before and after medication. The researchers also found that as BW increased, the locomotion ability of broilers tended to decrease. After birds received the analgesic, the peak vertical force increased among the more severely lame broilers at 35 to 49 d of age and their walking speed was decreased, indicating that they might have felt pain during locomotion. No difference was found between the femur (right and left) strength in response to a compression load; however, the results showed that femurs of 28-d-old birds were less resistant to compression (P < 0.05) than those of older broilers. The foot force platform was a useful tool for assessing the walking ability of broilers.

Nymphs in foraging populations of Coptotermes gestroi (Isoptera: Rhinotermitidae)

Food searching activity by subterranean termites involves workers, soldiers and nymphs. The present study was carried out for elucidating aspects of nymph foraging behavior in Brazil where the species Coptotermes gestroi (Wasmann, 1896) is exotic. Monitoring was conducted through making regular collections from seven different colonies for a period of 22 months, which exhibited the production of forager nymphs all year round. A biometric study was conducted to determine the instars of the forager nymphs collected. The identification of male and female nymphs was also conducted for establishing the sex proportion, which was slightly male-biased. From the 533 forager nymphs collected, 34 were from the 3rd instar, 280 from the 4th instar and 219 from 5th instar. The results suggest that 3rd instar nymphs were not too active in the foraging activities because they were collected only in one colony and in an insignificant quantity. (C) Koninklijke Brill NV, Leiden, 2011.

Tensile strength and histological changes of abdominal aorta of malnourished rats

The resistance of the abdominal aorta of rats after 6, 7 and 8 weeks of malnutrition, compared with control animals, was evaluated by longitudinal tensiometry. Weakness of this vessel in malnourished rats was demonstrated; microscopic examination of the aorta stained by Masson, Calleja and hematoxylin-eosin methods showed a decrease in amorphous ground substance and an increase in the width of elastic laminae. There was no visible alteration either in the endothelial lining layer or in the smooth muscle fibers. Such alterations of the aorta are, to the authors' knowledge, the first reported modifications in the peripheral vasculature after malnutrition.

Influência do fotoperíodo no crescimento e sobrevivência de póslarvas de piracanjuba Brycon orbignyanus (Valenciennes, 1849) (Osteichthyes, Characidae)

This paper aims at studying the influence of photoperiod on the cultivation of Brycon orbignyanus (Valenciennes, 1849) (Osteichthyes, Characidae) post-larvae submitted to four treatments: 0L-24D (L=Light; D=Dark), 10 - L14D, 14L - 10D and 24L-0D, with 3 repetitions. Post-larvae measuring 7.8±0.7mm and weighting 3.5±0.8mg were distributed in 12 aquariums (10L), stocked with 12 post-larvae per aquarium. Fishes were fed daily with Artemia sp. nanplii, in 10 days experiment. A positive relationship between the survival rate (88.9±9.7%) observed in the treatment with 24 hours of luminosity, and the lowest (58.3±8.3%), in the treatment with 24 hours of darkness. No difference was showed (P>0.05) in the mean length and weight of the post-larvae, although there was greater heterogeneity among the post-larvae cultivated at the longer darkness period.

Discriminating among earth composition models using geo-antineutrinos

It has been estimated that the entire Earth generates heat corresponding to about 40 TW (equivalent to 10,000 nuclear power plants) which is considered to originate mainly from the radioactive decay of elements like U, Th and K, deposited in the crust and mantle of the Earth. Radioactivity of these elements produce not only heat but also antineutrinos (called geo-antineutrinos) which can be observed by terrestrial detectors. We investigate the possibility of discriminating among Earth composition models predicting different total radiogenic heat generation, by observing such geo-antineutrinos at Kamioka and Gran Sasso, assuming KamLAND and Borexino (type) detectors, respectively, at these places. By simulating the future geo-antineutrino data as well as reactor antineutrino background contributions, we try to establish to which extent we can discriminate among Earth composition models for given exposures (in units of kt · yr) at these two sites on our planet. We use also information on neutrino mixing parameters coming from solar neutrino data as well as KamLAND reactor antineutrino data, in order to estimate the number of geo-antineutrino induced events. © SISSA/ISAS 2003.

Oxygen uptake kinetics and time to exhaustion in cycling and running: A comparison between trained and untrained subjects

The objective of the present study was to compare pulmonary gas exchange kinetics (VO 2 kinetics) and time to exhaustion (Tlim) between trained and untrained individuals during severe exercise performed on a cycle ergometer and treadmill. Eleven untrained males in running (UR) and cycling (UC), nine endurance cyclists (EC), and seven endurance runners (ER) were submitted to the following tests on separate days: (i) incremental test for determination of maximal oxygen uptake (VO 2max) and the intensity associated with the achievement of VO 2max (IVO 2max) on a mechanical braked cycle ergometer (EC and UC) and on a treadmill (ER and UR); (ii) all-out exercise bout performed at IVO 2max to determine the time to exhaustion at IVO 2max (Tlim) and the time constant of oxygen uptake kinetics (τ). The τ was significantly faster in trained group, both in cycling (EC = 28.2 ± 4.7 s; UC = 63.8 ± 25.0 s) and in running (ER = 28.5 ± 8.5 s; UR = 59.3 ± 12.0 s). Tlim of untrained was significantly lower in cycling (EC = 384.4 ± 66.6 s vs. UC; 311.1 ± 105.7 s) and higher in running (ER = 309.2 ± 176.6 s vs. UR = 439.8 ± 104.2 s). We conclude that the VO 2 kinetic response at the onset of severe exercise, carried out at the same relative intensity is sensitive to endurance training, irrespective of the exercise type. The endurance training seems to differently influence Tlim during exercise at IVO 2max in running and cycling. © 2003 Taylor & Francis Ltd.

The reproductive biology of Diplodus argenteus (Sparidae) in the coastal upwelling system of Cabo Frio, Rio de Janeiro, Brazil

The reproductive biology of the seabream Diplodus argenteus, a dominant coastal fishery species, was investigated over two consecutive seasons (2001-2002) at Cabo Frio, Brazil, a low-latitude upwelling system. The sex ratio was dominated by females (1.4:1.0) and the length-at-50% sexual maturity (females) was 203mm total length. Females were multiple spawners and the reproductive pattern appeared to be digynous protandrous hermaphroditism. Monthly variations in gonadosomatic index and proportion of ripe females indicated that reproductive activity occurred from late winter to summer (August-February), following coastal upwelling. Copyright © NISC Pty Ltd.

The use of the two-body energy to study problems of escape/capture Ernesto Vieira Neto1

The problem of escape/capture is encountered in many problems of the celestial mechanics -the capture of the giants planets irregular satellites, comets capture by Jupiter, and also orbital transfer between two celestial bodies as Earth and Moon. To study these problems we introduce an approach which is based on the numerical integration of a grid of initial conditions. The two-body energy of the particle relative to a celestial body defines the escape/capture. The trajectories are integrated into the past from initial conditions with negative two-body energy. The energy change from negative to positive is considered as an escape. By reversing the time, this escape turns into a capture. Using this technique we can understand many characteristics of the problem, as the maximum capture time, stable regions where the particles cannot escape from, and others. The advantage of this kind of approach is that it can be used out of plane (that is, for any inclination), and with perturbations in the dynamics of the n-body problem. © 2005 International Astronomical Union.

Transmission analysis of candidate genes for nonsyndromic oral clefts in Brazilian parent-child triads with recurrence

Cleft lip and/or palate (CL/P) is a major congenital defect with complex etiology, including multiple genetic and environmental factors. Approximately two thirds of the cases are not accompanied by other anomalies and are called nonsyndromic (NS). In the present study, we performed transmission distortion analysis of the MSX1-CA, TGFB3-CA and MTHFR-C677T polymorphisms in 60 parent-child triads, in which the NS-CL/ P affected child had at least one affected parent. No association with genes MSX1 or TGFB3 was found, but the results were suggestive of an association of the MTHFR-C677T polymorphism with NS-CL/P. © 2006 Sociedade Brasileira de Genética.

Multiparticulate systems of pectin-chitosan: Study of swelling and drug release

The aim of this study was to prepare multiparticulate systems of pectin:chitosan (PC:CS) and to evaluate their swelling ratio and the drug release in different environments. PC:CS particles containing triamcinolone were prepared by a complex coacervation/ionotropic gelation method in aqueous environment. The polymer ratio, the calcium concentration and the contact time of the capsules with chitosan dispersion for particles formation and the structures obtained were analyzed. The systems were characterized in relation to morphology, size, swelling, and drug release behavior. The methodology used allowed the production of spherical particles with narrow range of size distribution. The entrapment efficiency for triamcinolone was 84.31 ± 439. It was observed that the particles present a relatively low swelling ratio in acidic medium and a larger swelling ratio in enteric medium. The release profile was dependent on pH and can be related with the swelling ratio.