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181.
Jitendra Kumar Gautam Saripalli Vijay Gahlaut Neha Goel Prabina Kumar Meher Kaushlesh Kumar Mishra Prafulla Chandra Mishra Deepmala Sehgal Prashant Vikram Carolina Sansaloni Sukhwinder Singh Pradeep Kumar Sharma Pushpendra Kumar Gupta 《Euphytica》2018,214(11):219
The present study was conducted to study the genetic architecture of grain micronutrients (Zn, Fe and β-carotene contents), grain protein content and four yield traits in a spring wheat reference set comprising 246 genotypes. Phenotypic data on these traits recorded at two locations and the genotyping data for 17,937 SNP markers (obtained through outsourcing) were used for genome wide association study, which gave following results after Bonferroni correction using four methods: (1) single locus single trait analysis gave 136 marker-trait associations; (2) multi-locus mixed model gave 587 MTAs; (3) multi-trait mixed model gave 28 MTAs and (4) matrix-variate linear mixed model gave 33 MTAs. As many as 73 epistatic interactions were also detected. Keeping all the results in mind, nine most important MTAs were selected for biofortification. These markers were associated with three traits (GPC, GFeC and GYPP). These MTAs can be used in wheat improvement programs either using marker-assisted recurrent selection or pseudo-backcrossing method. 相似文献
182.
Immediate effects of diamond burr debridement in patients with spontaneous chronic corneal epithelial defects,light and electron microscopic evaluation 下载免费PDF全文
183.
Carolina Fernández-Ramos Oscar Ballesteros Alberto Zafra-Gómez Dalibor Šatínský Peter Solich Alberto Navalón Coral Verge Juan de Ferrer Miguel Perez-Pascual Jose Luís Vílchez 《Water, air, and soil pollution》2017,228(3):104
Irrigation with reclaimed water and soil amendment with sewage sludge are becoming common practices in arid and semiarid areas. When wastewater treatments do not efficiently remove all the contaminants, these contaminants can later end up in agricultural soils. These contaminated soils are a potential source of surface and groundwater pollution by leaching and runoff. In the present work, we assessed the behavior of alcohol sulfates (AS) in agricultural soil. For the experimental work, a tract of soil was irrigated with linear alcohol sulfates with 12–18 hydrocarbon chain and subsequently tested for AS concentration from November 2014 to July 2015. The highest concentrations of AS were found at the top layer of soil (29.80 to 6.23 mg kg?1). The adsorption rate and the amount of surfactant adsorbed increased as the length of the hydrocarbon chain increases. AS homologues can leach up to 60 cm. A mathematical model was applied to predict the environmental behavior of AS in the agricultural soils studied. Disappearance rate constant (k) values for AS homologues were between ?5.10·10?3 and ?1.68·10?2 h?1, and average half-life values were between 37 and 135 h. Coefficients of determination (R 2) between 92.4 and 99.1% showed that the proposed model satisfactorily describes the experimental results. The present study provides a conceptual framework and essential parameters for predicting and understanding the environmental behavior of AS in agricultural soils. 相似文献
184.
Background
Diversity patterns of different taxa typically covary in space, a phenomenon called cross-taxon congruence. This pattern has been explained by the effect of one taxon diversity on taxon diversity, shared biogeographic histories of different taxa, and/or common responses to environmental conditions. A meta-analysis of the association between environment and diversity patterns found that in 83 out of 85 studies, more than 60% of the spatial variability in species richness was related to variables representing energy, water or their interaction. The role of the environment determining taxa diversity patterns leads us to hypothesize that this would explain the observed cross-taxon congruence. However, recent analyses reported the persistence of cross-taxon congruence when environmental effect was statistically removed. Here we evaluate this hypothesis, analyzing the cross-taxon congruence between birds and mammals in the Brazilian Cerrado, and assess the environmental role on the spatial covariation in diversity patterns. 相似文献185.
The authors tested two mini-yarders, one for uphill and the other for downhill extraction. The two machines were modern commercial
models, offering state-of-the-art yarding technology on a miniature scale and at a much lower cost than required for purchasing
a full-size tower yarder. The two units must not be regarded as alternative, but rather as complementary, since they offer
different capabilities and advantages. Both machines were tested while harvesting firewood from the thinning of young beech
stands in Central Italy. The tests indicated that both units can reach a productivity between 1.5 and 2.4 m3 SMH−1, including all delays, as well as set-up and dismantle time. Calculated extraction cost ranged between 24 and over 30€ m−3. The authors calculated a set of regression equations for estimating machine productivity as a function of the main work
conditions. The performance of the studied mini-yarders does not seem much inferior to that achieved by professional light
tower yarder under the same work conditions, but the lighter construction of the small-scale units may result in a lower resistance
to wear and abuse. In any case, mini-yarders seem ideal for deployment under the typical conditions of small-scale forestry,
offering a good solution to wood extraction on steep terrain, competitive with animal and winch logging in terms of productivity,
cost and operator comfort. 相似文献
186.
Carolina C Otoni Sheila C Rahal Luiz C Vulcano Sérgio M Ribeiro Khadije Hette Tatiana Giordano Danuta P Doiche Renée L Amorim 《Acta veterinaria Scandinavica》2010,52(1):20
Background
Accurate early diagnosis of lung metastases is important for establishing therapeutic measures. Therefore, the present study aimed to compare survey thoracic radiographs and computerized tomography (CT) scans to specifically identify lung metastases in female dogs with mammary tumors.Methods
Twenty-one female dogs, weighing 3 to 34 kg and aged from 5 years to 14 years and 10 months, with mammary tumors were studied. In all dogs before the imaging examinations, fine-needle aspiration cytology of the mammary tumors was performed to confirm the diagnosis. Three-view thoracic radiographs were accomplished: right lateral, left lateral and ventrodorsal views. Sequential transverse images of the thorax were acquired on a spiral Scanner, before and after intravenous bolus injection of nonionic iodine contrast. Soft-tissue and lung windows were applied. All the mammary tumors were surgically removed and examined histologically.Results
The correlation between the cytological and histological results regarding presence of malignancy was observed in only 17 cases. In radiographic examinations, no dog displayed signs of lung metastases or thorax chest lesions. CT detected lung metastasis in two cases, while small areas of lung atelectasis located peripherally were found in 28.57% of the dogs.Conclusion
In this study population, spiral CT showed higher sensitivity than chest radiographies to detect lung metastasis; this indicates that CT should be performed on all female dogs with malignant mammary tumors. 相似文献187.
Hugo Pereira Luísa Custódio Maria Jo?o Rodrigues Carolina Bruno de Sousa Marta Oliveira Luísa Barreira Nuno da Rosa Neng José Manuel Florêncio Nogueira Salman A. Alrokayan Fouzi Mouffouk Khalid M. Abu-Salah Radhouan Ben-Hamadou Jo?o Varela 《Marine drugs》2015,13(6):3531-3549
Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 µg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and β-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value. 相似文献
188.
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190.
Although it is generally assumed that the reactivity of sucrose, a nonreducing sugar, in the Maillard reaction is due to its hydrolysis into free glucose and fructose, however, no direct evidence has been provided for this pathway, especially in dry and high temperature systems. Using specifically (13)C-labeled sucrose at C-1 of the fructose moiety, HMF formation was studied at different temperatures. Under dry pyrolytic conditions and at temperatures above 250 degrees C, 90% of HMF originated from fructose moiety and only 10% originated from glucose. Alternatively, when sucrose was refluxed in acidic methanol at 65 degrees C, 100% of HMF was generated from the glucose moiety. Moreover, the relative efficiency of the known HMF precursor 3-deoxyglucosone to generate HMF was compared to that of glucose, fructose and sucrose. Glucose exhibited a much lower conversion rate than 3-deoxyglucosone, however, both fructose and sucrose showed much higher conversion rates than 3-deoxyglucosone thus precluding it as a major precursor of HMF in fructose and sucrose solutions. Based on the data generated, a mechanism of HMF formation from sucrose is proposed. According to this proposal sucrose degrades into glucose and a very reactive fructofuranosyl cation. In dry systems this cation can be effectively converted directly into HMF. 相似文献