Effects of submergence in water on seed germination and vigor of the Copaifera lucens （Fabaceae） seedlings     

Daniela Baldez Vidal  ;Isis Leite Andrade  ;Eusinia Louzada Pereira Andrade  ;Marcelo Schramm Mielke 《林业研究》2014,25(4):903-908

We analyzed the tolerance of Copaifera lucens seeds to sub- mersion in water to assess the use of this species for direct seeding in riparian forest restoration programs. Seeds were submerged in water for 2, 4, 8, 16 and 32 days or not submerged （control = 0 days of submer- gence）. For the control and at the end of each period of submersion, germination and seedling vigor tests were carried out. For germination tests, seeds were sown in plastic pots containing sand and kept in labora- tory conditions. The percentage of seed germination, the germination rate and the average germination time were analyzed. For seedlings, total biomass, leaf area, leaf mass per area and leaf area ratio were analyzed. Submersion time drastically affected the dissolved oxygen content and seed germination. Between 4 and 8 days of submersion there was a de- crease from 83.8% to 15.6% in the germination percentage. No seed germination occurred after 16 days of submersion. Although there was a significant decrease in the percentage of seed germination between 4 and 8 days of submersion, seedling vigor was not affected. Seeds of this species were partially tolerant to submersion in water, suggesting that C. lucens is a promising species for direct seeding in riparian forest restora- tion projects.  相似文献   

Parameters of the Reproductive Tract,Spermatogenesis, Daily Sperm Production and Major Seminal Plasma Proteins of Tropically Adapted Morada Nova Rams     

FML Sousa  CH Lobo  ESB Menezes  JPA Rego  RV Oliveira  AC Lima‐Souza  M Fioramonte  FC Gozzo  RCFF Pompeu  MJD Cândido  JT Oliveira  AA Moura 《Reproduction in domestic animals》2014,49(3):409-419

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Immunolocalization of the Cholesterol Transporters ABCA1 and ABCG1 in Canine Reproductive Tract Tissues and Spermatozoa     

N Palme  AC Becher  M Merkl  M Glösmann  C Aurich  S Schäfer‐Somi 《Reproduction in domestic animals》2014,49(3):441-447

The mammalian sperm membrane undergoes cholesterol efflux during maturation and fertilization. Although ATP‐binding cassette (ABC) transporters are known to transport cholesterol through cell membranes in other organs, their presence in canine testis, epididymis and sperm has not been proven to date. Hence, the aim of the present study was to localize the ABC transporters ABCA1 and ABCG1 in canine testicular and epididymidal tissue as well as in spermatozoa membranes. To this end, semen samples from 12 dogs as well as testicles and epididymides of four young and healthy dogs were prepared for immunohistochemistry, respectively. Capacitation and acrosome reaction (AR) were induced in aliquots of the semen samples before immunostaining to assess changes in the expression of ABCA1 and ABCG1. Evaluation by confocal microscopy revealed the presence of both ABCA1 and ABCG1 in canine testicles and of ABCA1 in the epididymides. In spermatozoa, only ABCA1 immunoreactivity was detected, mainly in the region of the acrosome and midpiece. After induction of capacitation, ABCA1 signal persisted in the acrosome but disappeared after AR, indicating a loss of ABCA1 with the loss of the acrosome. We conclude that ABCA1 and ABCG1 are expressed in canine testis, whereas only ABCA1 is expressed in epididymis and spermatozoa membrane, both transporters probably contributing to the regulation of membrane cholesterol content.  相似文献   

Histomorphometrical study on the skin of different regions of the Caribbean common opossum (Didelphis marsupialis Linnaeus, 1758)     

Reda Mohamed  William Pérez  Marcelo Leite da Veiga 《Anatomia, histologia, embryologia》2021,50(1):144-150

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Tantalum Dissolution Rate in Simulant Lung Fluid     

C. Lima  M. J. Coelho  K. C. P. Dalia  C. V. Barros Leite  G. Medeiros  K. Dias da Cunha 《Water, air, and soil pollution》2007,186(1-4):365-371

The aim of this study is to determine the solubility rate of tantalum contained in pyrochlore, columbite–tantalite and columbite in simulant lung fluid. The International Commission on Radiological Protection (ICRP), in its recommendation for limiting intakes of radionuclide by workers, has consistently recognized that the biological behavior of any specific material after incorporation can significantly diverge from model prevision. Model parameters should be adjusted to adapt the model for each specific substance material in order to estimate the dose due to this element intake. The most recent ICRP publication 66, respiratory tract dosimetry model, point out that information as data like particle size, aerosols solubility and the material chemical compounds are important parameters in the dose coefficients calculation. This paper studies the solubility in Simulant Lung Fluid (SLF) of Ta present in mineral dust particles. For this study 3 minerals were selected: pyrochlore, columbite–tantalite and columbite. Tantalum dissolution in vitro samples were obtained using the Gamble solution and PIXE (Particle Induced X-ray Emission) as analytical technique. In order to characterize the worker exposure to Ta bearing particles, one Brazilian niobium mine was selected. The mineral dust particles were collected using a six-stage cascade impactor and the elemental mass concentrations and the MMAD (Mass Median Aerodynamic Diameter) were determined. Concentrations of radionuclides from natural series of thorium and uranium were also determined. The results show that the workers are exposed to Ta bearing particles in the respirable fraction of aerosols (aerodynamic diameter (d _aer) <2.5 μm) during the mineral processing to obtain Fe–Nb alloy. The solubility in Simulant Lung Fluid (SLF) of Ta present in mineral dust particles depends on the mineral characteristics. The solubility half-time varies between 34 and 62 h depending on the associated mineral.  相似文献   

Shading effect on physiological parameters and in vitro embryo production of tropical adapted Nellore heifers in integrated crop-livestock-forest systems     

Leite da Silva  Wilian Aparecido  Poehland  Ralf  Carvalho de Oliveira  Caroline  Ribeiro Ferreira  Mariane Gabriela Cesar  Garcia de Almeida  Ricardo  Cáceres  Mirela Brochado Souza  Macedo  Gustavo Guerino  da Costa e Silva  Eliane Vianna  Alves  Fabiana Villa  Nogueira  Eriklis  de Andrade Melo-Sterza  Fabiana 《Tropical animal health and production》2020,52(5):2273-2281

Tropical Animal Health and Production - The aim of this study was to evaluate the impact of increased shadow supply in integrated crop-livestock-forest systems on in vitro embryonic development and...  相似文献   

Spatial patterns of magnetic susceptibility optimized by anisotropic correction in different Alisols in southern Amazonas,Brazil     

Brito  Wildson Benedito Mendes  Campos  Milton César Costa  de Souza  Fernando Gomes  Silva  Laércio Santos  da Cunha  José Maurício  de Lima  Alan Ferreira Leite  Martins  Thalita Silva  de Oliveira  Flávio Pereira  de Oliveira  Ivanildo Amorim 《Precision Agriculture》2022,23(2):419-449

Precision Agriculture - Changes in primary cover for agricultural crops in Amazonas region influence the phenomenon of spatial variability in soil properties. This phenomenon is still studied...  相似文献   

Sun coral management effectiveness in a wildlife refuge from south-eastern Brazil     

Lucca A. C. Savio  Gustavo M. Dias  Kelen L. Leite  Silvia N. Godoi  Apoena C. Figueiroa  Geraldo F. O. Neto  Edineia C. Correa  Carlo L. B. Francini  Gustavo Shintate  Marcelo V. Kitahara 《水产资源保护:海洋与淡水生态系统》2021,31(10):2830-2841

1. The introduction of exotic species is one of the major causes for biodiversity loss in marine environments. Introduced species can change habitat complexity, impacting local communities and altering ecosystem functioning.
2. Since the 1980s, the scleractinian species Tubastraea coccinea and Tubastraea. tagusensis (commonly known as sun corals) have been spreading in the south-western Atlantic, posing a major threat to local biodiversity and marine ecosystems. Nowadays, these species are reported from more than 3,500 km along the Brazilian coast and on at least 21 oil and gas offshore platforms.
3. Considering the great environmental pressure resulting from sun coral invasion, this study verified the effectiveness of manual removal of Tubastraea spp. along a rocky shore in Alcatrazes Wildlife Refuge, one of the most pristine marine regions in Brazil.
4. Results indicate that removal is indeed effective as a control technique; however, as invaders have high regeneration capabilities and recruitment rates, successive management efforts are essential. In order for management to be effective against Tubastraea's year-round release of clonal larvae, results suggest invaded areas should receive at least two management actions per year.
5. Successive management efforts, in addition to the development of new techniques and prevention of new invasions should be priorities for mitigating sun coral impacts.

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Impact of the colonisation of Zaprionus (Diptera, Drosophilidae) in different ecosystems of the Neotropical Region: 2 years after the invasion     

Rosana Tidon  Denise Ferreira Leite  Bárbara Ferreira Dobbin Leão 《Biological conservation》2003,112(3):299-305

The drosophilid Zaprionus indianus was not collected in Brazil, despite on-going drosophilid collecting, until 1999. Since 1999 this species has become common in Brazil. We present data on collections of Z. indianus in central Brazil, since its first occurrence in this region, with the goal of discussing its route of introduction in South America and aspects of its adaptation to the environment. Collections made during a 2-year period show different seasonal distribution patterns of this insect. In contrast with the low population sizes registered in 1999, during the summer of 2000 a large proliferation of this insect was detected. We show that Z. indianus is more common in the savanna sites and that its population peaks during the wet season. These preferences are discussed, and the hypothesis that the introduction in South America should have occurred in the southeast region of this continent is defended.  相似文献   

Lunasin and Bowman-Birk protease inhibitor concentrations of protein extracts from enzyme-assisted aqueous extraction of soybeans     

Leite Nobrega de Moura JM  Hernandez-Ledesma B  de Almeida NM  Hsieh CC  de Lumen BO  Johnson LA 《Journal of agricultural and food chemistry》2011,59(13):6940-6946

Lunasin and Bowman-Birk protease inhibitor (BBI) are two soybean peptides to which health-promoting properties have been attributed. Concentrations of these peptides were determined in skim fractions produced by enzyme-assisted aqueous extraction processing (EAEP) of extruded full-fat soybean flakes (an alternative to extracting oil from soybeans with hexane) and compared with similar extracts from hexane-defatted soybean meal. Oil and protein were extracted by using countercurrent two-stage EAEP of soybeans at 1:6 solids-to-liquid ratio, 50 °C, pH 9.0, and 120 rpm for 1 h. Protein-rich skim fractions were produced from extruded full-fat soybean flakes using different enzyme strategies in EAEP: 0.5% protease (wt/g extruded flakes) used in both extraction stages; 0.5% protease used only in the second extraction stage; no enzyme used in either extraction stage. Countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes was used as a control. Protein extraction yields increased from 66% to 89-96% when using countercurrent two-stage EAEP with extruded full-fat flakes compared to 85% when using countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes. Extruding full-fat soybean flakes reduced BBI activity. Enzymatic hydrolysis reduced BBI contents of EAEP skims. Lunasin, however, was more resistant to both enzymatic hydrolysis and heat denaturation. Although using enzymes in both EAEP extraction stages yielded the highest protein and oil extractions, reducing enzyme use to only the second stage preserved much of the BBI and Lunasin.  相似文献