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1.
In tropical climate, huge amount of fertilizer need to be used for the cultivation of kenaf (Hibiscus cannabinus L.) in Beach Ridges Interspersed with Swales (BRIS) soil, however this approach is not cost effective and environmental friendly. Therefore, the optimizing of fertilizer rate for BRIS soils and selection of suitable soil amendments are crucial to get a higher yield. In this study, the effects of different combinations of urea, chicken manure and biochar on soil properties, growth performance and physiological characteristics of kenaf cultivated on the BRIS soil were investigated. Eight treatments were conducted namely: control (T1), biochar (T2), chicken manure (T3), urea (T4), chicken manure + urea (T5), biochar + chicken manure (T6), urea + biochar (T7) and biochar + chicken manure + urea (T8). The biomass and physiological characteristics of kenaf were recorded every month, while the soil was analyzed following a standard laboratory procedure. The application of organic and inorganic fertilizer (urea) significantly increased the nutrient content of the soil compared to the T1, whereas T3 showed the highest pH, cation exchange capacity, and exchangeable bases (Na, Mg, Ca). However, the mixing of biochar with organic and inorganic fertilizers showed the highest plant height, diameter of stem and number of leaves as well as dry biomass compared to other treatments. Furthermore, the application of nitrogen fertilizer significantly increased the photosynthesis rate and stomatal conductivity. The results suggest that the mixing of biochar with organic and inorganic fertilizers represents an effective approach for the cultivation of kenaf in tropical climate.  相似文献   
2.
Phosphate rock (PR) was activated via acidulation with HCl, EDTA, and oxalic acid to enhance its reactivity. The release, lateral transport, and uptake of phosphorus (P) along with trace metals from pristine and activated PRs were investigated in a soil micro-block system over a period of 27 days, using wheat (Triticum aestivum L.) plants. Significantly (p < 0.05) higher amounts of available soil P, Fe, Mn, and Zn were released from all the PRs after application to soil within first 9 days of seedling transplantation, while the release of other trace metals (Cd, Co, Cr, Cu, Ni, and Pb) was minimal (<1.2 mg kg?1). On cumulative basis, APR-O (oxalic acid activated PR) was the most efficient amendment releasing 164% more available P, followed by APR-E (EDTA activated PR) releasing 130% more available P, compared to the pristine PR. Similar results were also observed in the release of available Fe, Mn, Zn, and other trace metals. The highest diffusive mass fluxes for available P, Mn, Fe, and Zn in soil were observed after 3 days of seedling transplantation, which reduced subsequently. The uptake of P, Fe, Mn, and Zn by wheat plants was increased by 394%, 715%, 92%, and 91%, respectively, in APR-O application compared to the pristine PR, while it was increased by 280%, 188%, 16%, and 27%, respectively, in APR-E application compared to the pristine PR. Subsequently, APR-O and APR-E amendments resulted in enhanced shoot lengths, root lengths, shoot dry matter, and root dry matter contents of wheat plants. Hence, it was concluded that activation of PR with oxalic acid and EDTA prior to direct soil application may enhance the reactivity of PR and could serve as a cost-effect fertilization strategy for higher wheat crop production.  相似文献   
3.
ABSTRACT

The present study was conducted to assess the ability of AquaCrop model in predicting of grain and biological yield of rice genotypes in water management. A two-year field experiment was conducted at the experimental farm of the Iranian Rice Research Institute in Rasht, Iran from 2016 to 2017. The experiment was established in a split-plot design with two irrigation management (continuous submergence and end season water stress) as the main plot, fourth rice genotypes as the sub-plot and three replications. The goodness-of-fit between observed and simulated grain yield and final biomass was assessed by means of the coefficient of determination (R 2), the absolute and normalized root mean square errors (RMSE). The RMSEn of predicting grain yield at calibration and evaluation stages was in the range of 6–12% and 6–8% for biological yield. The results indicated that AquaCrop model is suitable to predict grain yield and biological yield of rice genotypes in northern Iran. AquaCrop model can be used to determine optimization strategies to improve the water consumption of rice genotypes.  相似文献   
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5.
Aquaculture International - A 56-day study was carried out to examine the addition of live foods a biofloc technology (BFT) system on Penaeus vannamei postlarvae performance (PL25, initial weight:...  相似文献   
6.
A 5‐week study was performed to evaluate the effect of spoilage date extract (SDE) as the biofloc carbon source on Litopenaeus vannamei (5.4 ± 0.3 g) performance. The two levels of dietary protein (15% and 25% crude protein) and two carbohydrate sources (molasses‐M and SDE‐P) were tested including: M15, M25, P15 and P25. The minimum (0.2 ± 0.0 mg/L) and the maximum (0.5 ± 0.0 mg/L) of total ammonia nitrogen were observed in the P15 and M25 groups respectively. The highest protein efficiency ratio (6.1 ± 0.3) and protein productive value (112.3 ± 5.8%) were found in the P15 group (p < 0.05). No significant difference was found between biofloc treatments in the expression of cathepsin L gene in hepatopancreas (p > 0.05). The number of total haemocyte count (THC), semigranular cells (SGC) and granular cells (GC) of shrimp in SDE‐based biofloc treatments was relatively higher than those in molasses‐based biofloc treatments. Following the white spot syndrome virus (WSSV) challenge, a significant decrease in THC, SGC, GC and hyaline cell values was observed in all treatments (p = 0.001). Plasma biochemical parameters were significantly influenced by dietary protein levels, biofloc carbon sources as well as WSSV challenge test. In conclusion, SDE successfully could be used as an alternative carbon source for establishing a biofloc system in L. vannamei production.  相似文献   
7.
Three E-cinnamic acid glycosides, tryptophan, and cyanidin-3-O-beta-D-glucopyranoside were isolated from ripe fruits of the Chilean strawberry Fragaria chiloensis ssp. chiloensis. 1-O-E-Cinnamoyl-beta-D-xylopyranoside, 1-O-E-cinnamoyl-beta-D-rhamnopyranoside, and 1-O-E-cinnamoyl-alpha-xylofuranosyl-(1-->6)-beta-D-glucopyranose are reported for the first time. The cinnamic acid glycosides and aromatic compound patterns in F. chiloensis fruits were determined by high-performance liquid chromatography (HPLC). HPLC analyses of extracts showed that cyanidin-3-O-beta-D-glucopyranoside and free ellagic acid are present in achenes while the E-cinnamoyl derivatives and tryptophan were identified only in the thalamus. The free radical scavenging effect of the fruit extract can be associated with the anthocyanin content.  相似文献   
8.
The interaction between particle size and resin content is one of the most important structural parameters that can influence the accuracy of predictions about wood-composite properties. We developed three kinds of equation (linear, quadratic, and exponential) for each mechanical property of particleboard based on slenderness ratio and resin content at a constant density (0.7g cm -3 ). Results from SHAZAM software (version 9) suggested that the quadratic function was not significant, but the linear and exponential functions were significant. The interaction between particle size and resin content was analyzed by Maple 9 software. The results indicated that an exponential function can better describe the simultaneous effect of slenderness and resin content than a linear equation. Under constant resin content, particles with higher slenderness ratios increased more in modulus of rupture (MOR) and modulus of elasticity (MOE) than did particles with lower slenderness ratios. Edge withdrawal resistance (SWRe) values did not increase with increasing slenderness ratio.  相似文献   
9.
Post cesarean (CS) pain is a challenging problem for the obstetricians, because it may interfere with mother and baby's well-being. Many approaches have been ever proposed to diminish this pain, each one with particular benefits and limitations. Aromatherapy is a complementary therapy especially for controlling pain. This study aimed at evaluating the effect of lavender essence on post CS pain. In a single-blind clinical trial, 200 term pregnant women with planned elective CS were recruited in a 12 month period of time. They were randomized in two 100-patient groups; received either lavender essence (the case group) or a similar clinically neutral aromatic material (the control group) thorough oxygen mask for 3 min 3 h after receiving similar intravenous analgesics. The Visual Analogue Scale (VAS) was employed to determine the level of post CS pain. The VAS was documented half hour after first intervention. Eight and 16 h later, the aromatherapy was repeated and half hour after each intervention, corresponding VAS was documented. The two groups were matched for demographics and obstetrical history. The baseline VAS was comparable between the two groups. The mean VAS decreased significantly by 16 h after the first intervention in both groups (p < 0.001). However, this amelioration of pain was significantly more prominent in the cases group comparing with that in the controls in all documented stages half hour, 8 and 16 h after the first intervention (p < 0.001 for all measurements). In conclusion, aromatherapy by using lavender essence is a successful and safe complementary therapy in reducing pain after CS.  相似文献   
10.
Bacground: Evidence from several lines of investigations suggests that Toll-like receptor 4 (TLR4) is involved in atherosclerosis as a bridge between innate and acquired immunity. Percutaneous coronary intervention (PCI) can trigger inflammation through activation of human TLR4 (hTLR4) on monocytes. Hydrocortisone as an anti-inflammatory and immuno-suppressant agent has multiple mechanisms of action. In this study, we aimed at assessing the effects of hydrocortisone on monocyte expression and activity of hTLR4 in patients underwent PCI. Methods: Blood samples were taken from a total of 71 patients with chronic stable angina who were scheduled for a PCI, before the intervention. Thirty patients received 100 mg hydrocortisone prior to the procedure. Control group was composed of 41 patients underwent PCI without receiving hydrocortisone. Blood collection was repeated 2 and 4 h after PCI. The expression of hTLR4 on the surface of CD14+ monocytes and the serum levels of TNF-α and IL-1β were measured using flowcytometry and Sandwich ELISA. Results: Compared with controls, hydrocortisone significantly reduced monocyte expression of hTLR4 in test group (P<0.01). In addition, it had a significant effect on reduction of serum concentrations of TNF-α and IL-1β in test group in a time-dependent manner (P<0.01). Conclusion: In this study, hydrocortisone was able to reduce the hTLR4/CD14 positive monocytes and its related pro-inflammatory cytokines, thus it can decrease inflammatory responses following PCI. Key Words: Toll-like receptor 4, Cytokines, Hydrocortisone  相似文献   
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