Biodegradation of Coir and Sisal Applied in the Automotive Industry

This paper discusses the results of biodegradability tests of natural fibers used by the automotive industry, namely: coir, coir with latex, and sisal. The biodegradation of coir, coir with latex, and of sisal fibers was determined by monitoring the production of carbon dioxide (CO(2)) (IBAMA-E.1.1.2, 1988) and fungal growth (DIN 53739, 1984). The contents of total extractives, lignin, holocellulose, ashes, carbon, nitrogen and hydrogen of the fibers under study were determined in order to ascertain their actual content and to understand the results of the biodegradation tests. The production of CO(2) indicated low biodegradation, i.e., about 10% in mass, for all the materials after 45 days of testing; in other words, no material inhibited glucose degradation. However, the percentage of sisal fiber degradation was fourfold higher than that of coir with latex in the same period of aging. The fungal growth test showed a higher growth rate on sisal fibers, followed by coir without latex. In the case of coir with latex, we believe the fungal growth was not intense, because natural latex produces a bactericide or fungicide for its preservation during bleeding [1]. An evaluation of the materials after 90 days of aging tests revealed breaking of the fibers, particularly sisal and coir without latex, indicating fungal attack and biodegradation processes.

Effect of nitrogen supply on growth and photosynthesis of sunflower plants grown in the greenhouse

The effects of nitrogen availability on growth and photosynthesis were followed in plants of sunflower (Helianthus annuus L., var. CATISSOL-01) grown in the greenhouse under natural photoperiod. The sunflower plants were grown in vermiculite under two contrasting nitrogen supply, with nitrogen supplied as ammonium nitrate. Higher nitrogen concentration resulted in higher shoot dry matter production per plant and the effect was apparent from 29 days after sowing (DAS). The difference in dry matter production was mainly attributed to the effect of nitrogen on leaf production and on individual leaf dry matter. The specific leaf weight (SLW) was not affected by the nitrogen supply. The photosynthetic CO2 assimilation (A) of the target leaves was remarkably improved by high nitrogen nutrition. However, irrespective of nitrogen supply, the decline in photosynthetic CO2 assimilation occurred before the end of leaf growth. Although nitrogen did not change significantly stomatal conductance (gs), high-N grown plants had lower intercellular CO2 concentration (C-i) when compared with low-N grown plants. Transpiration rate (E) was increased in high-N grown plants only at the beginning of leaf growth. However, this not resulted in lower intrinsic water use efficiency (WUE). (C) 2004 Elsevier B.V.. All rights reserved.

Endurance training stimulates growth and survival pathways and the redox balance in rat pancreatic islets

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

The limits of human development and the use of energy and natural resources

The development of nations is an unquestionable requirement. A lot of challenges concerning health, education and economy are present. A discussion on these development models has occupied the minds of decision makers in recent years. When energy supply and demand is considered, the situation becomes critical and the crucial question is: how to improve the quality of life of developing countries based on available models of development that are related to the life style of developed countries, for which the necessary use and waste of energy are present? How much energy is essential to humanity for not so as to endangering the survival conditions of future generations? the human development index (HDI) establishes the relationship among energy use, economic growth and social growth. Here it can be seen that 75% of the world population has a significant energy consumption potential. This is a strong reason to consider that the sustainable development concepts on energy policies are strategic to the future of the planet. This paper deals with the importance of seeking alternative development models for human development balance, natural resources conservation and environment through rational energy use concepts. (c) 2004 Elsevier Ltd. All rights reserved.

Effects of uracil calculi on cell growth and apoptosis in the BBN-initiated Wistar rat urinary bladder mucosa

The different potential of initiated and non-initiated urinary bladder mucosa (UBM) to develop neoplasia was quantitatively evaluated in the male Wistar rat. Initiation of carcinogenesis was accomplished with N-butyl-N- (4-hydroxybutyl) -nitrosamine (BBN). Stimuli for cell proliferation and apoptosis were obtained by exposure followed by withdrawal of 3% Uracil in the diet. The proliferation index (PI) was estimated in UBM immunostained for the proliferating nuclear cell antigen (PCNA). The apoptotic index (AI) and the density of papillary/nodular hyperplasia (PNH) were estimated in hematoxilin-eosin stained sections. PNH was the main proliferative response to the mechanical irritation by uracil, irrespective of previous initiation with BBN. Uracil exposure induced higher PI and PNH density in the initiated rats. After uracil withdrawal, there was a significant increase of the AI in both uracil-treated groups, which correlated well to the respective PNH density. However, at the end of the experiment, PNH incidence and density were significantly higher in the BBN-initiated mucosa, which also presented 18% incidence of papillomas and 27% of carcinomas. Therefore, under prolonged uracil calculi trauma, the UBM of BBN-initiated Wistar rats gives rise to epithelial proliferative lesions that progress to neoplasia through acquired resistance to apoptosis. (C) 1999 Wiley-Liss, Inc.

Effects of polymorphic microsatellites in the regulatory region of IGF1 and GHR on growth and carcass traits in beef cattle

Growth hormone (GH), insulin-like growth factors 1 and 2 (IGF1 and IGF2) and their associated binding proteins and transmembrane receptors (GHR, IGF1R and IGF2R) play an important role in the physiology of mammalian growth. The objectives of the present study were to estimate the allele and genotype frequencies of microsatellite markers located in the 5'-regulatory region of the IGF1 and GHR genes in beef cattle belonging to different genetic groups and to determine effects of these markers on growth and carcass traits in these animals under an intensive production system. For this purpose, genotyping was performed on 384 bulls including 79 Nellore, 30 Canchim (5/8 Charolais + 3/8 Zebu) and 275 crossbred animals originating from crosses of Simmental (1/2 Simmental, n = 30) and Angus (1/2 Angus, n = 245) sires with Nellore females. The effects of substituting L allele for S allele of GHR microsatellite across Nellore, Canchim and 1/2 Angus were significant for weight gain and body weight (P < 0.05). The IGF1 microsatellite allele substitutions of 229 for 225 within Nellore group and of 225 for 229 within 1/2 Angus were not significant for any of the traits.

Effects of incubation temperature on muscle morphology and growth in the pacu (Piaractus mesopotamicus)

This study describes the influence of incubation temperature during initial development phase on the morphology and muscle growth characteristics in the pacu (Piaractus mesopotamicus). Pacu eggs were incubated at 25, 27, and 29 degreesC until hatching. After day 5, fish from each temperature were transferred to 5001 tanks. At hatching and after 5, 25, and 60 days, muscle samples were collected, some were frozen in liquid nitrogen and others fixed in 4% paraformaldehyde or 2.5% glutaraldehyde. These samples were used for morphological, histochemical, immunohistochemical, and morphometric analysis. At hatching, we observed a superficial monolayer of small diameter fibers, lying just beneath the skin surrounding several round cells. From day 5, we observed two distinct populations of muscle fibers distributed in two layers: (1) red-in a superficial region with aerobic activity, and following acid preincubation, high mATPase activity, and 2) white-with anaerobic activity, and following alkaline preincubation, high mATPase activity. Twenty-five days after hatching, an intermediate layer and cell proliferating zones could be seen in the dorsal fin muscle region, with intermediate characteristics. Throughout the experimental period, there was an increase in muscle mass due to new fiber recruitment in the cell proliferating zones and between the more differentiated fibers in red, intermediate, and white muscles. This was more obvious from day 25, and at 29 degreesC than at 25 and 27 degreesC. Fiber hypertrophy occurred from hatching to 60 days and was more evident from 5 to 25 days. The number of proliferating nuclei (PCNA-labelling) increased from hatching to 60 days, and was more obvious in the 29 degreesC group at 60 days. Our results show that at incubation temperatures of 25, 27 and 29 degreesC, hypertrophy was predominantly from hatching to 25 days, after that muscle growth by hyperplastic mechanism increased. The interaction of muscle hypertrophic and hyperplastic growth processes in the 29 degreesC group produced the largest fish at the end of the experiment. (C) 2004 Elsevier B.V. All rights reserved.

Early social environment and the fighting behaviour of young Oreochromis niloticus (Pisces, Cichlidae)

This study examines the influence of early experience with different forms of aggressive behaviour on the fighting behaviour of young fish. Fry of the cichlid fish, Oreochromis niloticus, were raised from hatching in small groups consisting of a normal individual (the test fish) and either mutant conspecifics lacking the dorsal fin and thereby the ability to perform fin displays, or normal ones. Following a 63-day period of development in groups the test fish were confronted in their home tanks with an unfamiliar normal fish for 10 min. The fighting behaviour of the test fish was analyzed considering their previous group type (mutant or normal) and rank (alpha or beta). There was no difference between test fish in the rate and sequence of behaviour patterns used in fighting. However, test fish that had developed in mutant groups were rarely the first to bite in contests and had a longer latency to biting following the first bite of the stimulus fish than rest fish with normal experience. This finding is attributable to the form of aggressive behaviour experienced by the test fish during development but not to existing differences in the amount of aggression previously experienced, nor to previous rank, sex, or size relative to the stimulus fish. The results suggest that early experience influenced decision making by the test fish during the fight. The involvement of the fin displays and the possible mechanism of this influence are discussed.

Relative growth and sexual maturity of the stone crab Menippe nodifrons Stimpson, 1859 (Brachyura, Xanthoidea) in southeastern Brazil

O objetivo do presente estudo foi determinar o crescimento relativo e a maturidade sexual morfológica de Menippe nodifrons. As coletas foram realizadas na Praia Grande e Tenório, Ubatuba, São Paulo. Os caranguejos foram separados quanto ao sexo e mensurados na região da largura (LC) e comprimento da carapaça, comprimento e altura dos própodos quelares direito e esquerdo, largura do abdome (LA) nas fêmeas e comprimento do gonopódio (CG) nos machos. Obteve-se 399 indivíduos, sendo 195 machos e 204 fêmeas. Os machos atingiram a maturidade sexual com 29,7mm LC e as fêmeas com 31,6mm LC. Para as fêmeas a melhor relação que indicou a muda da puberdade foi LA vs. LC, sendo que o crescimento foi alométrico negativo na fase jovem e alométrico positivo após a muda da puberdade. Para os machos foi CG vs. LC evidenciando crescimento alométrico positivo na fase jovem e isométrico na fase adulta.

Growth and reproductive dynamics of the South American red shrimp, Pleoticus muelleri (Crustacea: Solenoceridae), from the southeastern coast of Brazil

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

Seed biometry and the effect of pre germinative treatments, temperature, and light on seed germination and subsequent growth of three Stryphnodendron species

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Age and growth of the Scalloped Hammerhead shark, Sphyrna lewini (Griffith and Smith, 1834), from the southern Brazilian coast

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

Tissue evidence of the testosterone role on the abnormal growth and aging effects reversion in the gerbil (Meriones unguiculatus) prostate

Prostate differentiation during embryogenesis and its further homeostatic state maintenance during adult life depend on androgens. Abundant biological data suggest that androgens play an important role in the development of the prostate cancer and other prostatic diseases. The objective of this work was to evaluate the effects of the testosterone supplementation in gerbil (a new experimental model) at different ages. Tissues from experimental animals were studied by histological and histochemistry procedures, androgen receptor immunohistochemistry assay, morphometric-stereological analysis, and transmission electron microscopy (TEM). After the treatment were observed increase of prostate weight and epithelium height in all ages studied. In some adult and aged treated animals, hyperplasic and displasic process were observed, including prostatic intraepithelial neoplasias and adenocarcinomas. Increase of the thickness of the smooth muscle cell (SMC) layer was observed in pubescent and adult animals and TEM revealed apparent SMC hypertrophy. An apparent increase in the frequency of blood vessels distributed by the subepithelial stroma in the treated animals was noticed. Reversion of the natural effects of aging on the prostate was observed in the aged treated animals in some acini of the gland. These data demonstrate that the gerbil prostate is susceptible to androgenic action at the studied ages and it can serve, for example, as experimental model to studies of prostate neoplasic process induction and hormonal therapy in aged animals.

Postnatal growth of the ventral prostate in Wistar rats: A stereological and morphometrical study

Morphological and stereological analyses were used to characterize the growth kinetics of the Wistar rat ventral prostate (VP). Volume density and absolute volume of the epithelium, lumen, smooth muscle cells (SMCs), and nonmuscular stroma were determined by stereology and paired with plasma testosterone levels and different morphometric measurements. The VP shows an initial growth within the first 3 weeks, a resting phase, and the puberal growth. The puberal growth was coincident with the raise in plasma testosterone. Lumen formation occurred within the 3 postnatal weeks. After an expected increase during puberty, the lumen showed a further increase at the 12th week. The volume density of the nonmuscular stroma and of the SMCs decreased slowly postnatally. Absolute volume of the luminal compartment showed three phases of growth (weeks 1-3, 6-9, and 11-12). on the other hand, the increase in the absolute volume of the epithelium was steady up to the 8th week and then showed a marked increase up the 10th week. The increase in epithelial volume was characterized morphologically by the presence of epithelial infoldings and sprouts. The growth of the epithelium showed a 2-week delay as compared to the lumen and occurred only until the 10th week. The epithelial height was variable but could be related to the synthetic activity of the epithelium. In conclusion, the postnatal growth of the VP results from a combination of epithelial proliferation/differentiation and synthesis/accumulation of the secretory products in the lumen.