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31.
The performance of the novel chitin metal silicate (CMS) co-precipitates as a single multifunctional excipient in tablet formulation using direct compression and wet granulation methods is evaluated. The neutral, acidic, and basic drugs Spironolactone (SPL), ibuprofen (IBU) and metronidazole (MET), respectively, were used as model drugs. Commercial Aldactone®, Fleximex® and Dumazole® tablets containing SPL, IBU and MET, respectively, and tablets made using Avicel® 200, were used in the study for comparison purposes. Tablets of acceptable crushing strength (>40 N) were obtained using CMS. The friability values for all tablets were well below the maximum 1% USP tolerance limit. CMS produced superdisintegrating tablets (disintegration time < 1 min) with the three model drugs. Regarding the dissolution rate, the sequence was as follow: CMS > Fleximex® > Avicel® 200, CMS > Avicel® 200 > Dumazole® and Aldactone® > Avicel® 200 > CMS for IBU, MET and SPL, respectively. Compressional properties of formulations were analyzed using density measurements and the compression Kawakita equation as assessment parameters. On the basis of DSC results, CMS co precipitates were found to be compatible with the tested drugs. Conclusively, the CMS co-precipitates have the potential to be used as filler, binder, and superdisintegrant, all-in-one, in the design of tablets by the direct compression as well as wet granulation methods.  相似文献   
32.
Recognizing the potential significance of using nuclear techniques in biological control, investigations were conducted on the rearing of parasitoids of the peach fruit-fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae) to lead to a greater flexibility in the use of irradiated hosts. For improving mass production of the biological control agents, the use of irradiated fruit-fly larvae at the dose of 15 Gy proved useful for enhancing the parasitism and adult emergence of the larval parasitoid, Trybliographa daci (Weld) (Hymenoptera: Eucoilidae) due to no negative repercussions on parasitoid development. Overall, parasitism by the parasitoid increased with age of the host larvae; however, significantly higher parasitism occurred on 4 d-old irradiated larvae of B. zonata compared to those aged 5 d. The female parasitoids preferred the irradiated larvae, and significantly higher numbers of larvae were parasitized compared with non-irradiated larvae. There was no significant difference in adult parasitoid emergence with respect to the sex of the host. A radiation level of 80 Gy was the best dose for rearing of the pupal parasitoid, Dirhinus giffardii (Silvestri) (Hymenoptera: Chalcididae) owing to broad tolerances in the use of irradiation for the rearing of fruit-fly's parasitoids. Percentage parasitism by D. giffardii varied with host pupal age, and the preference of the female parasitoid was lower on 48 h old host pharate pupae due to optimum size and mass of host. Present findings further revealed that the 24 h old host pupae of B. zonata were relatively more suitable for the maximum parasitism and progeny production of D. giffardii. Parasitisms by D. giffardii and T. daci were significantly higher on B. zonata host when parasitoids were released at a density of 3000 individuals per acre (7500 per hectares) than the other release rates of parasitoids for the management of fruit-flies in mango orchards. The implementation of these findings ought to help improve the mass production of parasitoids and the effectiveness of releases of biocontrol agents for control of B. zonata in mango plantations.  相似文献   
33.
Production of the Th1 cytokine interferon gamma (IFNγ) is associated with resistance to intracellular pathogens, including Rhodococcus equi. While neonatal foals are initially deficient in IFNγ production, expression of this cytokine increases throughout their first year of life. This is presumably the result of stimulation by environmental antigens including pathogen associated molecular patterns (PAMPS) signaling through toll-like receptors (TLR). This increased expression of IFNγ is likewise associated with an age-related resistance to R. equi infection. While immunostimulants containing PAMPS have been administered to adult horses in an attempt to modify their immune response, the effect of these materials on IFNγ expression in foals is unknown. The main objective of this study was to determine the effect of administering a commercial immunomostimulant EqStim? (Propionibacterium acnes) on IFNγ production measured using intracellular staining (IFNγ) and RT-PCR.  相似文献   
34.
The study was set up to evaluate the efficiency of amino acids and seaweed on vegetative growth, reproductive phase, yield, and postharvest storage quality of hydroponically grown bell pepper cultivars “Sven Rz F-1” and “Red Knight.” Different concentrations of amino acid and seaweed were sprayed on bell pepper plants under hydroponic conditions. Pre-harvest foliar application of amino acids and seaweed significantly increased plant height, number of leaves, leaf area, yield per plant, number of marketable fruits per plant, average fruit diameter, fruit wall thickness, and average single fruit weight. Amino acid and seaweed significantly improved postharvest physicochemical quality of both bell pepper cultivars under extended cold storage conditions. Conclusively, amino acid as well as seaweed extract not only improved growth, development, yield, and overall quality of bell pepper cultivars but also increased storage life with reduced weight loss and decay along with better physicochemical quality.  相似文献   
35.
In the present study, the effectiveness of biofertilizer containing plant growth promoting rhizobacteria was evaluated on growth and physiology of cotton under saline conditions. Cotton plants were exposed to different levels of NPK (50%, 75%, and 100% of recommended levels) along with coating with biofertilizer under saline (15 dS m?1) and non-saline conditions. It was observed that the biofertilizer seed coating improved growth, physiological (relative water content and chlorophyll content index), and ionic (K+/Na+) characteristics under saline and non-saline conditions. However, shoot growth (shoot fresh and dry weight) and leaf gas exchange characteristics (CO2 assimilation rate, A; intercellular CO2 concentration, Ci; transpiration rate, E; stomatal conductance, gs) were decreased by biofertilizer coating under saline condition. Increasing levels of NPK fertilizer increased shoot growth, whereas root growth was maximum at 75% NPK level under saline conditions. The results of the study indicate that the biofertilizer application was very effective for cotton plant in non-saline conditions but not very effective in saline conditions.  相似文献   
36.
Boron (B) deficiency is potentially an important nutrient constraint in calcareous soils. We determined B deficiency incidence and spatial distribution in rainfed wheat (Triticum aestivum L.) in 1.82 Mha Pothohar plateau in Pakistan, its relationship with soil types, crop responses to B, and internal B requirement and B fertilizer use efficiency of wheat. Plant and soil analyses indicated deficiency in 64% of the 61 sampled fields; geostatistics-aided contour maps delineated B deficient areas. In rainfed field experiments, B use increased wheat yields up to 11%. Fertilizer requirement was 1.2 kg B ha?1; critical B concentration (mg kg?1) ranges were: young whole shoots, 4–6; flag leaves, 5–7. Boron uptake by wheat was 0.14–0.58% of applied dosage, leaving substantial residual impact. Highly cost-effective B use or B-efficient genotype adoption can enhance wheat productivity and grower-income. Such effective nutrient assessment and management approaches can be beneficially adopted elsewhere as well.  相似文献   
37.
Growing tomatoes using saline water and in soils with poor nutrient contents is challenging. The objectives of this work were to: (i) examine the yield and quality of tomatoes (Lycopersicon esculentum L.) irrigated with different saline water [electrical conductivity (ECi) = 3, 6 and 9 dS m?1]; and (ii) study the effect of fertilizer: inorganic, organic, and a mixed of both on tomatoes grown under saline conditions. Fruit weight and quality attributes including size, color, soluble solids, acidity, EC, and pH were measured. Growing tomatoes under 3 and 6 dS m?1 produced the highest yield, whereas irrigating with 9 dS m?1 reduced yield. The mixed fertilizer slightly ameliorated the yield reduction caused by salinity. Using organic fertilizer alone produced the lowest fruit yield. Fruit quality was more affected by salinity than fertilizer. The best growing conditions for tomatoes were in plots irrigated with 6 dS m?1 water under mixed fertilizer treatment.  相似文献   
38.
Severe acidifications in acid sulfate soils (ASSs) have occurred worldwide due to sulfuric acidity, which requires sustainable measures for their reclamation. Accordingly, an incubation study was conducted with the topsoil of two different ASSs (Cheringa and Badarkhali) to evaluate the effects of basic slag (BS; size <1 mm, pH 9.6, Ca 20.8%, Mg 9.8%, etc.), on reduction of acidity and changes in exchangeable cations. It is noted that BS is a byproduct of steel industry in Bangladesh and can be collected almost free of charge. These soils received BS at the rate of 0 (T0), 11 (T1), 22 (T2) and 33 (T3) t ha−1 under various moisture regimes (saturated condition M1,, i.e., 100% moisture content, wetting–drying cycles of 100 and 50% moisture M2, and moisture at field condition M3, i.e., 50%). The impacts of these treatments on some selected parameters in these soils were studied within 180 days of incubation. The application of BS was found to increase the pH of soils from 3.6 to 5.1 for Cheringa, 3.9 to 5.2 for Badarkhali soils at the end of incubation. These increments were more striking with the highest doses of BS under saturated moisture conditions in both of the soils. The ECe of the soils was not much influenced by the application of BS regardless of time. The treatments exerted significant (P ≤ 0.05) effects on exchangeable cations in different periods of incubation. The striking changes were recorded for the rate of increments of Ca2+ and Mg2+, which were about 2–3 times higher for Ca and more than 2 times higher for Mg2+ compared with the control after 180 days of incubation. These results suggest that the application of BS not only increased the Ca2+ to the higher amount than that of the increment of Mg2+ in the soils, but also improved one of the important criteria of Ca2+ and Mg2+ ratio in the soils.  相似文献   
39.
The alkaloidal fraction obtained from an ethanolic extract of the leaves of Mikania cordata exhibited significant in vivo antiulcer activity in diclofenac sodium-induced gastric erosions in Long Evans rats.  相似文献   
40.

Though Biofloc Technology is a new concept in Bangladesh, it provides advantages for improving aquaculture production in many countries, leading to achieve sustainable development goals. The objectives of this study were to determine the effects of stocking densities on the growth performance of stinging catfish (Heteropneustes fossilis) under Biofloc Technology and assess the economic prospects and business feasibilities. Fingerlings were stocked in unique 5000-L tanks with three stocking densities, i.e., 3500 fish/tank (Treatment-I), 4000 fish/tank (Treatment-II), 4500 fish/tank (Treatment-III). The treatments showed significant differences (P?<?0.05) considering the species-specific growth rate, feed conversion ratio, and protein efficiency ratio. Treatment-I had significantly ((P?<?0.05) higher final biomass (29.51 ± 0.04 kg/m3) than the other treatments. The present findings revealed that using a lower stocking density, the Biofloc Technology reduced ammonia (NH3), nitrite (NO2), nitrate (NO3), TDS, and floc volume but significantly increased the dissolved oxygen. As a result, Treatment-I had generated significantly higher net income (BANGLADESHI TAKA—BDT 86,278.90) over the other treatments. Moreover, the NPV, net BCR, and RoR with 4% and 9% opportunity cost were also significantly higher in Treatment-I than other treatments. The internal rate of return (IRR) and SWOT analysis index indicates that investing in Biofloc Technology is far superior, and a stocking density of 3500 fish/tank (Treatment-I) resulted in a faster investment return.

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