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61.
The changes in color of sand dunes from white to yellow or red is often interpreted to signify their age or their source materials. In this study we demonstrate the effect seasonal inter-dune freshwater ponds have on the bleaching of the color of sand dunes by iron reduction in the anaerobic conditions they create. By combining spectral measurements of field samples of dune sand together with the analysis of satellite images covering three dune fields in NE Brazil (Lençóis Maranhenses, Jericoacoara and Canoa Quebrada) we demonstrate its existence in the field. In areas where ponds cover 41% of the dune field (as in Lençóis Maranhenses) an almost total bleaching in the color of the sand occurs after which the dunes remain white with no relation to distance from the coastline. In areas with less ponds (e.g. Jericoacoara or Canoa Quebrada) dune whitening is less active, and there are areas where dune rubification occurs. As this process may have occurred in other dune fields during past climate conditions that may have been different from current ones, interpretations of dunes age based on their color should be handled with care. 相似文献
62.
Felipe Farias Pereira da Câmara Barros Pedro Paulo Maia Teixeira Luciana Cristina Padilha-Nakaghi Ricardo Andres Ramirez Uscategui Marina Ragagnin Lima Victor José Correia Santos Kayan da Cunha Rossy Luísa Pucci Bueno Borges Marcia Rita Fernandes Machado Wilter Ricardo Russiano Vicente 《Reproduction in domestic animals》2020,55(4):442-447
We tested FSHp, eCG and FSHp + eCG to establish ovum pick-up (OPU) and in vitro maturation method in spotted paca. Eight healthy adult females were subjected to each of four treatments to stimulate ovarian follicular growth. All females were subjected to a hormonal protocol using a single dose of 45 mg of injectable progesterone and single intramuscular injection of 0.075 mg d-cloprostenol on day 6. Ovarian stimulation was carried out as follows: in Group TFE (FSHp and eCG), animals were treated with a single dose of 80 mg of FSHp and 200 IU of eCG intramuscularly on day 6 after the application of progesterone; in Group TF (FSHp), they were treated with a single dose of 80 mg of FSHp intramuscularly on day 6 after application of progesterone; in Group treatment eCG, they were treated with 200 IU of eCG intramuscularly on day 6 after application of progesterone; and in Group TC (saline solution), 1 ml of saline solution was administered to control does. The OPU was performed between 22 and 26 hr after gonadotropin treatments. All recovered oocytes were placed into maturation media and incubated for 24 hr. There were no differences among the mean number of observed follicles, aspirated follicles and oocytes recovered per treatment. Oocyte maturation rates did not differ among groups, except, TF and treatment eCG oocytes had greater maturation rates than TC oocytes. In this study, gonadotropin administration failed to superovulate treated does and increase oocyte retrieval efficiency. Despite the feasibility of the procedure, further studies are needed to develop and refine hormonal protocols for oocyte recovery and in vitro maturation in this species. 相似文献
63.
Eliene Matos Silva Natoniel Franklin de Melo Alessandra Monteiro Salviano Mendes Francisco Pinheiro de Araújo Leonor Costa Maia 《Journal of plant nutrition》2015,38(3):431-442
The Caatinga is a unique biome that encompasses nearly 11% of Brazil's territory and contains diverse vegetation composed of trees and bushes that have been scarcely studied from the economic perspective. In this context, Passiflora setacea may constitute a strategic alternative for agriculture because it produces fruit that has commercial potential and is tolerant to some diseases. Some species of Passiflora show more robust growth when associated with arbuscular mycorrhizal fungi (AMF) and are dependent on mycorrhization. In this study, the response of P. setacea to phosphate (P) fertilization and mycorrhization with Claroideoglomus etunicatum was evaluated. The experimental design included eight replicates of four randomized treatments: non-inoculated plants (NI), plants fertilized with phosphorus (P), mycorrhized plants (AMF), and plants that were both fertilized and mycorrhized (P+AMF). The plant height, leaf number, leaf area, fresh biomass (FB), and dry biomass (DB) of the shoots and roots, nutrient content, mycorrhizal colonization (MC), and the number of glomerospores (NG) in the rhizosphere were evaluated. The MC and the NG were reduced by phosphate fertilization. The development of the mycorrhized plants was significantly better than the NI and P treated plants for all of the variables tested. Inoculation with C. etunicatum promoted the growth of P. setacea seedlings even in the absence of phosphate fertilization, reducing production costs and strengthening the potential of P. setacea as a viable agricultural alternative for the semiarid region. 相似文献
64.
Camila Pegoraro Liliane Marcia Mertz Luciano Carlos da Maia Cesar Valmor Rombaldi Antonio Costa de Oliveira 《Journal of Crop Science and Biotechnology》2011,14(2):85-95
Abiotic and biotic stress conditions cause extensive losses to maize production, mainly due to protein dysfunction in these
conditions. In higher plants, the occurrence of heat-shock proteins (HSPs) in response to different environmental stresses
is a universal phenomenon and has been well documented. Many studies have demonstrated that most HSPs are involved in many
regulatory pathways, act as molecular chaperones for other cell proteins, and have strong cytoprotective effects. Although
many functional roles for HSPs are known, the mechanisms for these multiple functions are not entirely understood. Here we
reviewed the correlation among HSP genes/proteins and plant tolerance, especially maize, in different environmental stresses. Due to the low availability of
information regarding the expression of HSP genes in response to different stresses in maize, we decided to mine databases in order to generate new insights related
to this topic. 相似文献
65.
Martins Tda M da Paixão TA Costa ÉA Pires Ade C Santos RL Borges ÁM 《Veterinary immunology and immunopathology》2011,139(2-4):277-281
Toll-like receptors (TLRs) and β-defensins are important components of the innate immune system. This study aimed to evaluate endometrial mRNA levels of TLRs (1/6, 2, 4, and 5) and β-defensin 5 in Holstein cows by quantitative real time RT-PCR. Uterine biopsies were performed from 6 to 12 h after parturition, and cows were divided into two groups: (i) cows with placental retention and clinical signs of uterine infection until 45 days postpartum (n=10) or (ii) cows with normal puerperium (n=10). All cows had detectable levels of TLRs and β-defensin 5 mRNAs, but these levels did not differ between groups (P>0.05). Levels of TLR4 mRNA had a positive and significant correlation with the time required for uterine involution in both groups. 相似文献
66.
de Souza Anderson Fernando Pascual Carolina Jubran Maia Beatriz Tofani do Valle De Zoppa André Luis 《Veterinary research communications》2022,46(1):283-288
Veterinary Research Communications - This study aimed to evaluate the distribution of dye at two perineural injection sites of the palmar/plantar nerves and describe their anatomical variations of... 相似文献
67.
Langer Gitta Jutta Fuchs Sebastian Osewold Johannes Peters Sandra Schrewe Falk Ridley Maia Kätzel Ralf Bubner Ben Grüner Jörg 《植物病害和植物保护杂志》2022,129(6):1285-1295
Journal of Plant Diseases and Protection - European ash dieback caused by the alien, invasive ascomycete species Hymenoscyphus fraxineus currently represents, along with its side effects, the... 相似文献
68.
Maia Fradkin María Rosa Ferrari Víctor Ferreira Ezequiel Martín Grassi Eduardo José Greizerstein Lidia Poggio 《Genetic Resources and Crop Evolution》2012,59(2):231-237
Triticum–Thinopyrum amphiploids arose from the need to obtain forage grasses highly resistant to pest, drought, soil salinity and frost and they
can be used as efficient bridges to transfer desired genes from wheatgrass species to wheat. One of them is trigopiro SH16
INTA, it was introduced in Argentina in 1947 but its genomic composition was unknown. The aim of this work was to determine
the chromosome number and genomic and chromosome composition of trigopiro SH16 INTA in order to use it in breeding programs.
The simultaneous use of the in situ hybridization technique with different probes (genomic DNA of Th. ponticum (Podp.) Barkworth et D.R. Dewey, pSc119.2 and pAs1) allowed us to conclude that the chromosome number of trigopiro SH16 is
2n = 42 and the genome composition would be: 14 chromosomes of the B genome, the 2D and 4D chromosome pairs of wheat, 14 chromosomes
of the J genome of Thinopyrum and the remaining chromosomes probably belong to the A genome of wheat. 相似文献
69.
Renata G. Souza Danielle Karla A. Silva João Ricardo G. Oliveira Bruno T. Goto Fábio Sérgio B. Silva Everardo V.S.B. Sampaio Leonor C. Maia 《Pedobiologia》2012,55(6):303-309
The exploitation of minerals from coastal dunes in northeastern Brazil requires subsequent revegetation for ecosystem recovery. In mined dunes areas, we have compared the growth of Guazuma ulmifolia and Tabebuia roseo-alba seedlings using substrates containing 10 or 15% of cattle manure, uninoculated or inoculated with a mixture of native arbuscular mycorrhizal fungi (AMF) or exotic AMF (Acaulospora longula). The inoculated plants had a higher percentage of colonization than those that were uninoculated. Plants of G. ulmifolia had the highest growth when inoculated with native AMF and fertilized with 10% manure or inoculated with A. longula and fertilized with 15% manure. In general, fertilization with 15% manure did not produce greater seedling development and had a negative effect on the effectiveness of the symbiosis. Twenty one AMF species were recorded in the planting areas at the end of the experiments, with a predominance of species that form acaulosporoid spores in areas with T. roseo-alba and gigasporoid spores in areas with G. ulmifolia plants. The incorporation of 10% cattle manure and native AMF in the substrate of T. roseo-alba and G. ulmifolia seedlings contributes to the initial establishment of plants in the field and to the incorporation of AMF propagules in the soil of the revegetated mined dunes. 相似文献
70.
Lage IN Paulino PV Pires CV Villela SD Duarte Mde S Valadares Filho Sde C Paulino MF Maia BA Silva LH Teixeira CR 《Tropical animal health and production》2012,44(2):361-367
The performance, intake, feed efficiency, and carcass traits of beef cattle from different gender profile were assessed. Fifteen
animals (five steers, five spayed heifers, and five intact heifers) with ±250 kg of initial body weight were randomly assigned
in individual pens and fed the same diet for 106 days. At the end of the trial, all the animals were slaughtered and the pH,
temperature, and weight of the carcass were recorded. The right side of each carcass was then separated into chuck, shoulder,
flank sirloin, and round for evaluation of commercial cuts yield. The left carcass sides were ribbed between the 12th and
13th ribs where the rib eye area and fat thickness measurements were taken. The 9th–11th rib section was removed from the
left half carcass and then dissected into muscle, fat, and bones in order to estimate carcass composition. Gender had no effect
(P > 0.05) on performance, intake, digestibility of dry matter and all the nutrients evaluated, feed efficiency, and carcass
characteristics. It can be concluded that steers and heifers (spayed or not) have the same potential to produce beef. From
a productive and welfare standpoint, there is no reason to spay heifers. 相似文献