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91.
Mohammad T. Ridha Md Arshad Hossain Ismail S. Azad Maria Saburova 《Aquaculture Research》2020,51(10):4225-4237
This study compared the effect of three sources of carbohydrates: sugar, wheat and malt flours, on water quality, water consumption, bacterial load, growth and flesh quality of Nile tilapia. Adults (120.6 ± 0.64 g) were stocked in 1.2‐m3 fibreglass tanks at a rate of 25 fish/m3. Carbohydrates were added to the biofloc tanks at a C:N ratio of 20:1. Water flow in the non‐biofloc control tanks was adjusted to 0.6 L/day. The 105‐day experiment was conducted in triplicates. Results showed that biofloc treatments (BFT) with zero water exchange had significantly higher mean total ammonia, nitrites, nitrates, alkalinity, total suspended solids and lower pH than the control treatment. The sugar BFT had the highest floc volume. Growth parameters and feed conversion ratio did not differ significantly among treatments. However, tilapia in the malt flour and control treatments had close values. Gross fish yield was higher (p < .05) in the control than the BFT treatments. Water consumption/kg tilapia produced in the control was 42 times higher than the BFT groups. Protozoa dominated the biofloc biota, and wheat flour was the best in harbouring higher bacterial populations in the gut. Protein content and ∑n‐3 fatty acids were highest in the wheat flour biofloc, while malt flour biofloc had the highest lipids. The sugar biofloc had the highest n‐3/n‐6 ratio. Tilapia muscles in the malt flour and control treatments had the highest protein and lipid contents respectively. Tilapia muscles in the wheat flour BFT had the highest ∑n‐3 fatty acids and n‐3/n‐6 ratio. It can be concluded that farming tilapia in BFT using malt or wheat flours as carbon sources is more economical in saving great amount of water with minimal discharge of pollutants without affecting tilapia growth or flesh quality. 相似文献
92.
Riyad Ismail Horst Kassier Morries Chauke Francesco Holecz Nico Hattingh 《Southern Forests》2015,77(3):203-211
In commercial forestry, regular terrestrial enumerations of the growing stock are required for the valuation, sustain-able management and planning of current and future timber supplies. In this study we examined whether the combination of synthetic aperture radar (ALOS PALSAR) and optical satellite (SPOT 4) image data can accurately predict the timber volume of even-aged Eucalyptus plantations located in South Africa. Results from this study show that the combination of ALOS PALSAR and SPOT 4 produces a R 2 value of 0.68 for the planted model, whereas the coppiced model produced a R 2 value of 0.55. However, by including stand age as an independent variable in the stepwise model, there was a 15% improvement for the planted model, whereas the coppiced model produced a 27% improvement. The final model developed in this study produced a R 2 value of 0.83 and a RMSE of 31.71?m3 ha?1 for planted stands, whereas the model for coppiced stands produced a R 2 value of 0.82 and a RMSE of 27.70?m3 ha?1. As it is not practical or financially feasible for commercial forestry companies to carry out terrestrial enumerations for all plantations on an annual basis, the model developed in this study presents an alternative and accurate method to calculate timber volume for even-aged Eucalyptus plantations. 相似文献
93.
Browell EV Butler CF Fenn MA Grant WB Ismail S Schoeberl MR Toon OB Loewenstein M Podolske JR 《Science (New York, N.Y.)》1993,261(5125):1155-1158
Stratospheric ozone and aerosol distributions were measured across the wintertime Arctic vortex from January to March 1992 with an airborne lidar system as part of the 1992 Airborne Arctic Stratospheric Expedition (AASE II). Aerosols from the Mount Pinatubo eruption were found outside and inside the vortex with distinctly different distributions that clearly identified the dynamics of the vortex. Changes in aerosols inside the vortex indicated advection of air from outside to inside the vortex below 16 kilometers. No polar stratospheric clouds were observed and no evidence was found for frozen volcanic aerosols inside the vortex. Between January and March, ozone depletion was observed inside the vortex from 14 to 20 kilometers with a maximum average loss of about 23 percent near 18 kilometers. 相似文献
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96.
Magaji G. Usman Oladosu Yusuff Mohammad Y. Martini Mohd R. Ismail Raihana Ridzuan 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):252-264
ABSTRACTDomestic production of chilli in Malaysia is insufficient which accounted for 52% self-sufficiency level. Poor performance of local varieties under high temperatures above 42°C is one of the major factors affecting chilli production. This study was conducted with the objective of introgress heat-tolerant gene (Hsps) from AVPP0702 donor into Kulai using marker-assisted backcrossing. A total of 68 SSR markers, including Hsp linked markers that showed polymorphism between the parents were used to assess the generation of backcrossing; BC1F1, BC2F1, BC3F1 and BC3F2 and the average RPG percentage of the recurrent parent was found to be 81, 90, 95 and 97%, respectively. The pattern of Hsp expression in the backcross generations was similar to the donor parent (upregulated with more than 4-fold increase). Twelve improved heat tolerant chilli lines were developed. Most of the morphological and agronomical traits were recovered in the selected improved heat-tolerant genotypes from Kulai such as plant height, number of days to 50% flowering, number of fruits, fruit length and total fruit yield per plant. Improved high-yielding heat-tolerant chilli lines showed tolerance to high temperature as well as did not express any negative effect on agronomic traits in comparison with Kulai variety. 相似文献
97.
H.?Yildiz?DasganEmail author Kazim?Abak Ismail?Cakmak Volker?R?mheld Suat?Sensoy 《Euphytica》2004,139(1):51-57
By using two tomato genotypes, 227/1 (Fe chlorosis susceptible) and Roza (Fe chlorosis tolerant), and their reciprocal F1, F2 and BC1 generations, the inheritance of tolerance to leaf Fe deficiency chlorosis of Roza was studied. Plants were grown in a nutrient solution and subjected to 2.0 × 10–6 M Fe EDDHA and 10 mM NaHCO3 to induce Fe deficiency stress by stabilization of pH to 7.8–8.2. A rating scale of 1–3 for chlorophyll was used and both monogenic and polygenic inheritance hypotheses were tested. Better responses to Fe deficiency, as measured by SPAD meter values, were obtained from the cross Roza × 227/1 than from the reciprocal cross. Data from F2 and BC1 suggest Fe chlorosis tolerance of Roza is to be controlled by polygenic loci with a relatively high additive effect. 相似文献
98.
Doaa H. Elsayed Heba M. A. Abdelrazek Fakhri E. El-Azzazi Shimaa A. A. Ismail Yasmina K. Mahmoud 《Reproduction in domestic animals》2020,55(4):469-478
This study was designed to investigate the hormonal and metabolic factors associated with placental retention in buffaloes with respect to the roles of oxidative stress biomarkers and serotonin receptors. Blood samples were collected at weeks 3, 2 and 1 pre-partum and at calving from 37 buffaloes; thirty normally dropped their placentae (Non-RFM group) and 7 dropped their placentae after 12 hr post-calving (RFM group). Serum progesterone (P4), oestradiol, cortisol, non-esterified fatty acids (NEFA), beta-hydroxybutyric acid (BHBA), antioxidant/oxidant biomarkers and mineral concentrations were assessed. Histopathology and histochemistry were implemented to detect collagen in foetal placental tissues. Immunohistochemistry for serotonin receptors in placental tissues was performed. Significant elevations in P4, cortisol, NEFA, BHBA and oxidative biomarkers concentrations were observed in the RFM group. However, oestradiol, antioxidants and mineral concentrations were significantly lower in RFM buffaloes than Non-RFM group. Histopathological examination revealed degenerative changes and necrosis in retained placental tissue compared with that in normal placental tissues. Serotonin receptors were significantly expressed with collagen condensation in retained placental tissues. Furthermore, inferior reproductive performance was pronounced in the retained group. In conclusion, retained foetal membranes in buffaloes were associated with hormonal imbalance, metabolic perturbation, oxidative stress, serotonin receptor upregulation and markedly reduced fertility indices. 相似文献
99.
Fatema Hoque Shikha Mohammed Ismail Hossain Katsuji Morioka Satoshi Kubota Yoshiaki Itoh 《Fisheries Science》2006,72(4):870-876
ABSTRACT: In order to elucidate the mechanism of the changes in gel forming characteristics of fish meat by pH-lowering, the gelation-temperature curve and the gelation-moisture content curve were examined using the acidified walleye pollack surimi or neutralized one after acidification. In the gelation-temperature curve, the gel strength was highest at 30°C and lowest at approximately 50–60°C, irrespective of pH shifting. The gel strength at 30°C and 80°C decreased with the decrease in pH value. The neutralization of acidified surimi improved the gel strength, but it was considerably lower than the original gel strength. The gel strength at 50–60°C was not affected by pH lowering. The gel strength at 80°C could not be revived to the original by pH readjustment, either in the presence or in the absence of EDTA. These results suggest that irreversible changes of meat protein take place under the low pH, and the oxidation ability of sulfhydryl (SH) groups of protein molecule is not affected by pH-shifting. 相似文献
100.
Wibowo A Ahmat N Hamzah AS Sufian AS Ismail NH Ahmad R Jaafar FM Takayama H 《Fitoterapia》2011,82(4):676-681
A new resveratrol trimer, malaysianol A (1), five known resveratrol oligomers: laevifonol (2), ampelopsin E (3), α-viniferin (4), ε-viniferin (5), diptoindonesin A (6), and bergenin (7) have been isolated from the acetone extract of the stem bark of Dryobalanops aromatica by combination of vacuum and radial chromatography techniques. Their structures were established on the basis of their spectroscopic evidence and comparison with the published data. The cytotoxic activity of the compounds was tested against several cell lines in which compound 4 was found to inhibit strongly the growth of HL-60 cell line. 相似文献