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关键词： Olea europaea L.   Partial root-zone drying   Water status   Osmoregulators   Secondary metabolites   Antioxidants   Phytohormones  

摘要： Changes in the plant water status, biochemical and hormonal responses, were investigated in three olive cultivars (Arbequina, Arbosana and Chetoui) grown in a super-high-density orchard under partial root-zone drying (PRD) irrigation. Four irrigation treatments were applied during two growing seasons (2015 and 2016);control treatment (100 % ETc) irrigated at 100 % of crop evapotranspiration on both parts of the root-zone and three PRD irrigation treatments (100 % PRD, 75 % PRD and 50 % PRD) irrigated at 100 %, 75 %, and 50 % of crop evapotranspiration only on one alternated part of the root-zone. The results indicated that the three studied olive cultivars showed a clear difference in their response to PRD irrigation. Arbequina cultivar has shown a conservative strategy for using water since relative water content (RWC) and stem water potential (Psi(stem)) were reduced more in Arbosana and Chetoui under PRD irrigation. In fact, PRD irrigation has led to a strong activation of secondary metabolites with antioxidant properties such as pigments, phenols and flavonoids. Other metabolic changes, including the accumulation of soluble sugars and proline have been also triggered by PRD irrigation. Among the studied cultivars, Arbequina displayed the highest levels of proline, total soluble sugars, phenols and flavonoids, and the lowest ones for Malondialdehyde (MDA) and hydrogen peroxide (H2O2). The increase in Superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (POD) activity and the reduction in polyphenoloxidase (PPO) activity under PRD irrigation were more pronounced in 2016 season with highest activities obtained from cultivar Arbequina. For all the three cultivars, PRD irrigation increased phytohormones concentration in both, roots and leaves and the highest levels were recorded in 2016. In leaves, Arbequina showed the lowest levels of abscisic acid (ABA), and the highest levels of jasmonic acid (JA), salicylic acid (SA) and indole-3-acetic acid (IAA).

关键词： fish   muksun   the Lena   amino acids   vitamins   minerals   biological and nutritional value  

摘要： Studies were carried out to determine the biochemical composition and nutritional value of muksun (Coregonus muksun (Pallas)) in the lower reaches of the Lena River. This is a valuable commercial fish; 90% of its total catch in Yakutia is covered by the Lena River, while its abundance is low in other rivers and continues to decrease due to overfishing. The average annual catch of muksun is 450 t and its total allowable catches are 510–590 t in Yakutia. It is noted that the fillet and belly of muksun are considered protein products in terms of protein content (15–20%). Thus, the protein content was 16.05 ± 0.003% in its fillet and 18.72 ± 0.009% in its belly. With respect to the fat content in the belly (22.67 ± 0.009%), muksun is a particularly fatty fish variety (over 15%). With respect to the nutritional value, muksun is considered a high-calorie food product (over 200–300 kkal/100 g). The proteins of the muksun fillet and belly have a high biological value, since the amount of amino acid score is higher than the ideal protein standard (over 100%). This research gives grounds to classify muksun meat as a high-quality and well-balanced food product.

关键词： Cerebrolyin   Reserpine   Anti-depressant   Inflammation   Regulatory CREB/BDNF signaling Pathway   Brain monoamines  

摘要： Depression is a major psychological disorder that contributes to global health problem. This study aimed to evaluate the anti-depressant effect of Cerebrolysin (CBL) in Reserpine-induced depressed rats, its effect on oxidative stress, inflammation, regulatory cyclic AMP-dependent response element binding protein (CREB)/brain derived neumtropic factor (BDNF) signaling pathways, brain monoamines and histopathological changes was assessed. Rats received either the vehicle or Reserpine (0.5 mg/kg, i.p.) for 14 days. The other three groups were pretreated with CBL (2.5, 5 ml/kg;i.p.) or fluoxetine (FLU) (5 mg/kg, p.o.), respectively for 14 days, 30 min before reserpine injection. Then analyses were conducted. CBL reversed Reserpine-induced reduction in latency to immobility and prolongation of immobility time in the forced swimming test (FST), reduced malondialdehyde (MDA), elevated reduced glutathione (GSH), reduced tumor necrosis factor-alpha (TNF-alpha), and elevated BDNF cortical and hippocampal brain contents. CBL elevated protein kinase A (PKA) and nuclear factor kappa-B (NF-kappa B) cortical and hippocampal protein expressions. CBL also ameliorated alterations in mRNA expressions of protein kinase B (AKT), CREB and BDNF in the cortical and hippocampal tissues. CBL elevated nor-epinephrine (NE), semtonin (5-HT), and dopamine (DA) and reduced 5-Hydroxyindoleacetic acid (5-HTAA), 3,4-Dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) cortical and hippocampal contents. CBL effects were in parallel to those observed with the standard anti-depressant drug, FLU. This study shows that CBL exerted antidepressant effect evidenced by attenuation of oxidative stress and inflammation as well as enhancement of neurogenesis, amelioration of monoaminergic system and histopathological changes.

关键词： Biomass   Ethyl levulinate   Furfuryl alcohol   Levulinic acid   Carbon cryogel   Urea-furfural  

摘要： Biomass-derived intermediate chemicals, such as furfuryl alcohol (FA) and levulinic acid (LA) are feeds for ethanolysis reaction to produce ethyl levulinate (EL). EL is a promising chemical that can be used as a biofuel additive and precursor for chemical synthesis, such as g-valerolactone. The present study conducted the ethanolysis of FA and LA using modified carbon cryogel as heterogeneous catalysts for improving the EL yield. The carbon cryogel (UCC) precursor was produced from urea and furfural, and modified via sulfonation. Iron (Fe) doping was then conducted to improve the surface chemistry of the catalyst. The catalytic activity of sulfonated carbon cryogel (UCC-S) was evaluated for LA ethanolysis, and the UCC-S-Fe prepared from the incorporation of Fe on UCC-S was utilised to catalyse FA ethanolysis. The effects of reaction parameters (i.e., time, molar ratio of ethanol to feed, catalyst loading, and reaction temperature) were significant on the catalytic performance. High EL yield of 95.8 mol% and 95.4 mol% were obtained from the ethanolysis of LA and FA, respectively. The performance of ethanolysis of carbohydrates and various biomass samples was evaluated to determine the EL yield using UCC-S-Fe. Both UCC-S and UCC-S-Fe were characterised using FTIR, XRD, TGA, NH3-TPD, BET, and SEM-EDX. The modification of UCC via sulfonation and Fe-doping improved the catalyst properties, and UCC-S-Fe demonstrated the potential to enhance biomass conversion to EL. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Martial arts   Caffeine   Specific task performance   Ergogenic aid   Athletic performance   Fat metabolism  

摘要： Background Nutritional ergogenic aids are foods or nutrients that can improve physical performance. Among these foods with ergogenic properties, caffeine has shown that it can increase the fat catabolism, strength, and improve the cognition and time reaction of an athlete, therefore, it is hoped that it can improve the performance of judokas. This study through a double-blind crossover (supplement X placebo) protocol, investigated the effects caffeine supplementation (single capsule containing 5 mg/kg body mass intake 60 min before the session) on biochemical, anthropometrical, physical, subjective and hemodynamic variables measured before, during and after two typical judo trainingcxs sessions (120-min: 40-min of gymnastics;40-min of specific technics and;40-min of judo combat). Methods 8 high-level athletes (21.4 +/- 2.0 years;83.6 +/- 15.2 kg;1.8 +/- 0.1 m;17.9 +/- 7.0 Fat%) were evaluated before and after each training for body mass, hydration, upper and lower limb power, performance in the special judo fitness test (SJFT), free fatty acids (FFA) in plasma, uric acid, glucose, lactate, heart rate, and pain. In addition, heart rate, FFA in plasma, uric acid, glucose, lactate, rating of perceived exertion and pain were assessed during the training. Results At 120 min, supplementation resulted in a higher concentration of plasma FFA (1.5 +/- 0.5 vs. 1.0 +/- 0.3 mmol/L;p = 0.047) and lactate (4.9 +/- 1.8 vs. 3.0 +/- 1.2 mmol/L;p = 0.047), and a lower concentration of uric acid (5.4 +/- 0.9 vs. 7.0 +/- 1.5 mg/dL;p = 0.04). Supplementation also resulted in performance maintenance (fatigue index) in the SJFT (Delta 0.3 +/- 2.0 vs Delta 1.7 +/- 2.5, for caffeine and placebo respectively, p = 0.046). No adverse effects were observed. Conclusion Based on the applied dose, intake time, and sample of this study, we can conclude that caffeine produces an ergogenic biochemical effect, and improves performance in judo athletes.

关键词： TBECH   Diastereomer-specific   Plant   Phytotoxicity  

摘要： The phytotoxicities of TBECH diastereomers to plants at the biochemical and molecular levels were investigated in a hydroponic study by using maize as a model plant. The results showed that TBECH could induce the production of two species of reactive oxygen species (ROS), O-2(center dot-) and H2O2, in maize tissues. The accumulation of ROS was the highest when maize was exposed to beta-TBECH. TBECH enhanced the phosphorylation of plant histone, and the contents of gamma-H2AX in maize followed the order beta-TBECH > alpha beta-TBECH > gamma delta-TBECH > gamma-TBECH. Transcriptome profiling revealed that antioxidant enzyme genes (AEGs) were over-expressed in maize when stressed by technical grade TBECH. The RT-PCR detection further validated that three typical AEGs, including CAT, SOD, and POD genes, were time-dependent and selectively expressed under the influence of TBECH diastereomers. Molecular compositions of maize root exudates characterized by FT-ICR-MS were significantly different among the four groups of TBECH diastereomer treatments. TBECH diastereomers specifically affected the chemical diversity and abundance of root exudates. New insights into the biochemical effects of TBECH on plants are provided in this work, which is helpful to deepening the understanding of their stereo-selectivity. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Rock art   Pigments   Rock weathering   Scanning electron microscope   Minerals-microorganism interaction   Ethiopia  

摘要： Over the past decade, physical and chemical analyses have been widely applied to the study of rock art contexts, particularly to examine the composition of rock art paintings and for direct radiometric dating. Different sampling and analytical methods have been applied to rock art from different parts of the world. However, in Africa these analyses are still at an embryonic stage. The results are often problematic in terms of reliability, mainly as concerns the chronology. This is due to a wide range of fossil and active biodegradation processes affecting rock surfaces and pigments;such processes are still widely underestimated. This paper aims to discuss the state of the art of the physical and chemical analyses undertaken on African rock art contexts, and the urgent need to establish protocols and best practices for sampling and analysis. The preliminary results of a new project in southern Ethiopia are presented here as an example of an integrated study of a rock art context, combining Archaeology and Earth Sciences. Preliminary field observations and SEM-EDS analyses, run on samples from two rock shelters in the Borana area, reveal the presence of a complex set of physical, chemical, and biological weathering processes with manifold effects on the rock art evidence.

关键词： Nitrogen   Nitrogen use efficiency   Nitrification inhibitors   Urease inhibitors   N-cycling   Banding  

摘要： 'Stabilised' nitrogen (N) represents an important category of enhanced efficiency fertilizers (EEFs) in which chemicals added to urea granules inhibit target soil N transformation processes in order to optimize N availability for crop uptake. However the mechanistic understanding of how these inhibitors perform when urea-based fertilizers are banded, causing substantial modifications to the soil chemical environment, is poorly understood. In a 16-day laboratory incubation, the efficacies of the nitrification inhibitor (NI), 3,4-dimethylpyrazole phosphate (DMPP), and the urease inhibitor (UI), N-(n-butyl) thiophosphoric triamide (NBPT), were investigated in two soils by incubating two commercially available urea-based products containing these additives in bands at concentrations equivalent to 150 kg N ha(-1) at row spacing of 1.8 m. When compared to a granular urea standard, DMPP did not provide any inhibitory benefits except when the inhibitor was able to diffuse beyond the zone affected by urea-N hydrolysis, within which considerable nitrification inhibition occurred because of the chemical conditions. The benefit of the NI was most significant in the soil with higher clay, organic matter and pH buffering capacity, with these properties confining the ureolytic-induced chemical changes and N transformations inhibitory zone closer to the fertilizer band. In contrast, the UI provided some benefit by slowing the rapid rise in pH, electrical conductivity and aqueous ammonia observed in standard urea bands, although the effects of NBPT were temporary (ca. 9 days) in both soils. The benefit of NI and UI technology relative to urea alone is likely to vary considerably between soils and fertilizer application methods. This study provides a physico-chemical approach to determining under what conditions the benefits of banded 'stabilising' EEF technology may be realised.

关键词： Antioxidant defense system   Glutathione-S-transferase   Glutathione   Histopathology   Mitochondria-rich cells   Prochilodus lineatus  

摘要： The flavonoid metal-insecticide [Mg(hesp)2(phen)], denominated MgHP, has high potential for controlling agricultural pests. If applied in large scale, it may reach aquatic ecosystems and be harmful to the biota. This study evaluated the effects of MgHP in the gills of the Neotropical fish, Prochilodus lineatus by determining the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione s-transferase (GST), and the levels of glutathione (GSH) and lipid peroxidation (LPO) after 24 and 96 h exposure to 0, 1, 10, 100 and 1000 mu g L-1. The histopathological changes with emphases to mitochondria-rich cells (MRC) were evaluated as well. After 24 h exposure the enzyme activities and the GSH and LPO levels were unchanged however, after 96 h exposure to high MgHP concentration (1000 mu g L-1), the GST activity and GSH levels increased. Oxidative stress measured as LPO levels did not occur after MgHP exposure in both periods. Gill tissue alterations increased after MgHP exposure to 10, 100 and 1000 mu g L-1. Cellular atrophy, pillar cells changes, filament epithelium hyperplasia and hypertrophy, lamellar epithelium hyperplasia were the most frequent histopathology. MRC in the filament epithelium decreased after exposure to 24 h and increased after 96 h indicating possible transitory osmo-ionic disruption. P. lineatus exhibited high tolerance to MgHP. The increased GST activity and GSH levels after 96 h exposure suggested possible MgHP accumulation and concentrationand time dependent response. Histopathology in the gills of exposed fish occurred at high MgHP concentrations. These results suggested that the MgHP into water, at high concentrations, affect the gills by changing GST activity, GSH levels and histology being useful biomarkers for MgHP water contamination.

关键词： Phenol degradation   Rhodococcus   Temperature tolerance   Comparative genome analysis   Gene copy number  

摘要： A novel phenol-degrading strain was isolated and identified as Rhodococcus ruber C1. The degradation analysis shows that 1806 mg/L of phenol can be completely degraded by strain C1 within 38 h, and the maximum specific growth rate (mu(max)=1.527 h(-1)) and maximum specific phenol degradation rate (q(max)=3.674 h(-1)) indicate its excellent phenol metabolism capability. More importantly, phenol can be degraded by strain C1 in the temperature range of 20-45 degrees C within 72 h, and with longer degradation time, phenol can be completely degraded even at 10, 15 and 50 degrees C. The whole genome of strain C1 was sequenced, and a comparative genome analysis of strain C1 with 36 other genomes of Rhodococcus was performed. A remarkable gene family expansion occurred during the evolution of Rhodococcus, and a comprehensive evolutionary picture of Rhodococcus at genomic level was presented. Moreover, the copy number of genes involved in phenol metabolism was compared among genus Rhodococcus, and the results demonstrate high phenol degradation capability of strain C1 at genomic level. These findings suggest that Rhodococcus ruber C1 is a bacterium capable of degrading phenol efficiently in the temperature range of 10-50 degrees C.