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881.
Luma Castro de Souza Luana Moraes da Luz Jéssica Taynara da Silva Martins Cândido Ferreira de Oliveira Neto Juscelino Gonçalves Palheta Tamires Borges de Oliveira Ediane Conceição Alves Risely Ferraz de Almeida Raimundo Leonardo Lima de Oliveira Roberto Cezar Lobo da Costa Nariane Quaresma Vilhena 《林业研究》2018,29(6):1475-1479
The objective of this work was to evaluate the effect of different water deficiency and rehydration levels on the concentrations of osmoregulators in two plant species (Hymenaea courbaril and H. Stigonocarpa) in the Amazon. We adopted a 2 × 5 × 5 factorial system, referring to 2 species (H. courbaril and H. stigonocarpa) and 5 stages of hydration and rehydration. The five hydration and rehydration stages were established in: (1) Control treatment E0; (2) Plants with 13 days of stress after incubation—E13; (3) Plants with 26 days of stress E26; (4) The plants that were established after 26 days after incubation and rehydrated for two days (RD2); (5) rehydrated for two days (RD4). The plants that were established after 26 days after incubation and rehydrated for four days. The experiment totaled fifty young plants with five replicates. Biochemical measurements were performed at the beginning of the experiment (E0) at 13 (E13) and 26 (E26) days after the water stress, in which the plants were rehydrated, repeating the analyses after two (RD2) and four (RD4) days. Both species increased the sucrose concentration by 18%, with a decrease of 52% in starch content. The RD4 time presented the highest mean starch concentration (0.19 mmol g?1 of the residue for H. courbaril and 0.27 mmol g?1 of residue for H. stigonocarpa). Increased proline concentrations were recorded for controls until RD2 for both species. For glycine betaine, the highest increases in treatments E26 and RD2 were observed for the H. courbaril species. Our rehydration period was not sufficient for total recovery of pre-stress concentrations of all studied solutes. 相似文献
882.
Alice Bosco-Santos Wanilson Luiz-Silva Elton Luiz Dantas 《Water, air, and soil pollution》2018,229(11):365
This study tested for the first time 147Sm/144Nd and 143Nd/144Nd ratios as tracers of rare earth element (REE) sources in semi-terrestrial organisms from a subtropical estuary affected by fertilizer industry activities. The isotopic composition of claw muscles and shells of male crabs (Ucides cordatus) were obtained by thermal ionization mass spectrometry, and provided contrasting signatures incorporated from the physical components by the biota. Our findings showed that crab shells had isotopic compositions similar to seawater, while the claw muscles incorporated the isotopic signature of sediments contaminated by fertilizer. The isotopic ratios (147Sm/144Nd and 143Nd/144Nd) proved that the anthropogenic source is transferring contaminants to the crabs, emerging as a reliable tool to diagnose REE pathway and source to the biota in impacted environments. 相似文献
883.
Jailson L. Cruz Daniel R. LeCain Alfredo A. C. Alves Mauricio Antônio Coelho Filho Eugênio Ferreira Coelho 《Archives of Agronomy and Soil Science》2018,64(12):1623-1634
We evaluated the possibility of elevated CO2 concentration ([CO2]) to reduce the negative effect of drought on growth and physiological parameters of cassava (Manihot esculenta Crantz). Plants were grown with 390 ppm or 750 ppm of CO2, under well-watered or under water deficit conditions. The study was conducted in a climate-controlled greenhouse using 14 L pots, for 100 days. For any value of fraction of transpirable soil water (FTSW) the carbon assimilation was always higher for plants grown under elevated [CO2]. Still, elevated [CO2] reduced the negative effect of drought on transpiration, water use efficiency, all growth measures and harvest index. Elevated [CO2] increased the dry matter of tuber roots (DMTR) of well-watered plants by 17.4%. The DMTR of plants grown under water deficit were 124.4 g and 58.9 g, respectively, for plants under elevated and ambient CO2, an increase of 112%. Thus, the CO2 effect was relatively stronger to the production of tuberous roots when cassava were subjected to water-deficit. Our results suggest that cassava tuber production might be resilient to changes in precipitation that will accompany higher atmospheric CO2 and reinforce cassava as a specie that can significantly contribute to mitigate hunger in a changing climate environment. 相似文献
884.
Intestinal development of bovine foetuses during gestation is affected by foetal sex and maternal nutrition
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T. R. S. Gionbelli P. P. Rotta C. M. Veloso S. C. Valadares Filho B. C. Carvalho M. I. Marcondes M. F. L. Ferreira J. V. F. Souza J. S. A. A. Santos L. C. Lacerda M. S. Duarte M. P. Gionbelli 《Journal of animal physiology and animal nutrition》2017,101(3):493-501
We aimed to evaluate the effects of maternal nutrition (MN) and foetal sex on the intestinal development of bovine foetuses throughout different days of gestation (DG). Forty‐four multiparous, dry Holstein × Gyr cows with average initial body weight of 480 ± 10 kg were fed the same diet of either restricted feeding at 1.15% of body weight (CO, n = 24) or fed ad libitum (overnourished, ON, n = 20). Six cows from CO group and five cows from ON group were slaughtered at 139, 199, 241 and 268 DG, and foetuses were necropsied to evaluate the intestinal development. The mass, length and density of foetal intestines were not affected by MN (p ≥ 0.260). An interaction between MN and DG was observed for the villi length of jejunum (p = 0.006) and ileum (p < 0.001). Villi length of jejunum and ileum was higher (p < 0.10) in foetuses from ON‐fed cows than in foetuses from CO‐fed cows at 139 DG. However, at 199 DG, the villi length of jejunum and ileum of foetuses from CO‐fed cows was higher than in foetuses from ON‐fed cows. Despite these differences, MN did not affect the villi length of jejunum and ileum at 268 DG (p > 0.10). Female foetuses had greater small intestine mass (p = 0.093), large intestine mass (p = 0.022), small intestine mass in proportion to body mass (p = 0.017) and large intestine mass in proportion to body mass (p < 0.001) than male foetuses. Female foetuses had also longer small intestine (p = 0.077) and greater small intestine density (p = 0.021) and villi length of jejunum (p = 0.001) and ileum (p = 0.010) than males. We conclude that MN affects the pathway for the development of foetal villi length throughout the gestation in bovine foetuses without changing the final villi length. Female foetuses had higher intestinal mass, density and villi length than males during the foetal phase in bovines. 相似文献
885.
Protected fatty acid supplementation during estrus synchronization treatment on reproductive parameters of dairy goats
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Juliana dos Santos Kuhner Oliveira Jeferson Ferreira da Fonseca Joanna Maria Gonçalves Souza‐Fabjan Luciana Vieira Esteves Luiz Fernando Rodrigues Feres Carla Aparecida Florentino Rodrigues Rodolpho de Almeida Torres Filho Juliana de Oliveira Felipe Zandonadi Brandão 《Animal Science Journal》2017,88(2):254-258
This study evaluated the effect of the protected fatty acid inclusion during estrus synchronization on reproductive parameters. Goats (n = 32) received progestagen sponges for 6 days and 200 IU equine chorionic gonadotropin and 30 µg d‐cloprostenol were given on Day 5. No difference was found among control (C), 1% protected fatty acid inclusion (C + 1%) or 4% protected fatty acid inclusion (C + 4%) groups, respectively, in estrus (100.0, 100.0 or 90.9%), estrus duration (31.6 ± 12.3; 43.2 ± 12.9 or 40.8 ± 14.1 h), animals ovulating (100.0, 90.0 or 100.0%) or ovulation rate (1.3 ± 0.5; 1.1 ± 0.3 or 1.2 ± 0.4). The interval from sponge removal to ovulation and from estrus to ovulation, respectively, were shorter for C + 4% (45.2 ± 8.0 h; 18.3 ± 11.0 h) compared with C (56.3 ± 12.6 h; 30.6 ± 10.5 h) or C + 1% (57.7 ± 8.7 h; 30.3 ± 11.1 h). The average ovulatory follicle diameter was smaller for C + 4% (6.2 ± 0.7 mm) than C (7.5 ± 0.8 mm), but similar to C + 1% (7.0 ± 1.5 mm). Insulin, insulin‐like growth factor 1, glucose and progesterone concentrations were similar among groups. The inclusion of protected fatty acid during synchronization treatment promoted no benefits on ovulation rate, but 4% anticipated the ovulation time. 相似文献
886.
First insights into insecticidal activity against Aedes aegypti and partial biochemical characterization of a novel low molecular mass chymotrypsin‐trypsin inhibitor purified from Lonchocarpus sericeus seeds
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Luiz CP Almeida Filho Pedro MS Tabosa Denise C Hissa Ilka M Vasconcelos Ana FU Carvalho 《Pest management science》2018,74(6):1362-1373
BACKGROUND
Arboviroses such as dengue, Zika and chikungunya represent a serious public health issue as a consequence of the absence of approved vaccines or specific antiviral drugs against the arboviruses that cause them. One way to prevent these diseases is by combating the vector mosquito, Aedes aegypti (Diptera), which has serine proteases in the midgut. Protease inhibitors are molecules that can block enzyme activity, impairing digestion and nutrition, which can lead to death. Thus, we purified and characterized a novel chymotrypsin‐trypsin inhibitor (LsCTI) from Lonchocarpus sericeus seeds and investigated its effect upon Ae. aegypti egg hatching, larval development and digestive proteases.RESULTS
LsCTI showed a single protein band in sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS‐PAGE), and the molecular mass determined by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS) was 8870.45 Da. Kinetics analyses revealed a noncompetitive type of inhibition and low inhibition constant (Ki) for chymotrypsin (8.24 x 10‐8 m ). The thermal resistance was remarkable, even at 100 °C for 180 min. The inhibitor concentration required for 50‐percent enzyme inhibition (IC50) of LsCTI was 4.7 x 10‐7 m for Ae. aegypti midgut larval enzymes. LsCTI did not affect egg hatchability at 0.3 mg mL‐1, but caused a high larval mortality rate (77%) and delayed development (37%).CONCLUSIONS
LsCTI is a novel protease inhibitor with remarkable biochemical characteristics and is a potential tool to control Ae. aegypti development. © 2017 Society of Chemical Industry887.
Teixeira RR Barbosa LC Forlani G Piló-Veloso D Walkimar de Mesquita Carneiro J 《Journal of agricultural and food chemistry》2008,56(7):2321-2329
A series of 34 3-benzyl-5-(arylmethylene)furan-2(5H)-ones, designed using the naturally occurring toxins nostoclides as a lead structure, was synthesized as potential inhibitors of the photosynthetic electron transport. All compounds were fully characterized by IR, NMR (1H and 13C), and MS spectrometry. HMBC and HSQC bidimensional experiments allowed 13C and 1H assignments. Their biological activities were evaluated in vitro as the ability to interfere with light-driven reduction of ferricyanide by isolated spinach chloroplasts. About two-thirds of the compounds exhibited inhibitory properties in the micromolar range against the basal electron flow from water to K3[Fe(CN)6]. The inhibitory potential of these 3-benzyl-5-(arylmethylene)furan-2(5H)-one lactones is higher than that of other nostoclide analogues previously synthesized in the same laboratories. 相似文献
888.
This study determined the concentration of 3-alkyl-2-methoxypyrazines in Frontenac and Leon Millot wines made from grapes that were naturally or artificially infested with the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae). Headspace sampling with solid-phase microextraction (SPME) and gas chromatography (GC) was used for the quantification of 3-isopropyl-2-methoxypyrazine (IPMP), 3- sec-butyl-2-methoxypyrazine (SBMP), and 3-isobutyl-2-methoxypyrazine (IBMP). The resulting method parameters included linearity (r2 > 0.98), limit of detection (>0.25 ng/L), relative standard deviation (<20%), and recovery (75-125%). IPMP concentrations in wine were not significantly different among the levels of natural or artificial infestations of H. axyridis. SBMP was found only in wine artificially infested with H. axyridis. IBMP was found in wine artificially infested with H. axyridis and in Frontenac wine, but not in Leon Millot. The consequences of these results for future research in the contamination of wine with H. axyridis are discussed. 相似文献
889.
Hung Trieu T. Almeida Auro C. Eyles Alieta Ratkowsky David Lam Vu T. Mohammed Caroline 《New Forests》2019,50(5):785-804
New Forests - Management options to optimise sawlog production from Acacia hybrid (A. mangium?×?A. auriculiformis) combining thinning and fertiliser treatments were applied at six... 相似文献
890.
Natália Martins Teixeira Reges Heinrichs Carolina Santos B. Bonini Joshua Afzal Guilherme Constantino Meirelles Cecilio Viega Soares Filho 《Journal of plant nutrition》2019,42(1):89-98
The intensification of livestock yield requires advances in the management and fertilization of forage crops. This study was conducted to determine the dry weight yield (DWY) along with the concentration and amount of nutrients of Megathyrsus maximum cv. Mombasa. The treatments were arranged in a factorial scheme 6?×?2, six leaf rates of Zn chelate and two soil types (Entisols and Ultisol) with low and medium Zn content and four replicates. Entisols with low Zn content and Ultisol with average Zn content were used plus a control treatment with Zn sulfate. The Zn chelate and Zn sulfate foliar application did not affect the DWY. The tillering and DWY were higher in Ultisol than in Entisol. The Zn content in DWY was directly proportional to rate chelated Zn. The root dry weight yield of Mombasa grass reduced with the chelated Zn foliar application in Entisol and had no effect on Ultisol. 相似文献