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141.
142.
Mohd. Masood Hussain Nageswara Rao Amanchi Venkata Ramanaiah Solanki Mohan Bhagavathi 《Pesticide biochemistry and physiology》2008,90(1):66-70
One of the major changes that have occurred over the past few years is the re-examination of conventional methods and the global demand for innovative low cost bioassay tests for assessing water quality, toxicity evaluation and bioremediation. In the present study acute toxicity, physiological and cytotoxic impact of carbofuran to a commonly occurring fresh water ciliate was measured. Intrinsic cytotoxicity was evident on macro nuclear apparatus that exhibited deformities such as fragmentation, deep incision, vacuolization and degenerative macronucleus. Depletion in the food vacuole formation of Paramecia was evident. Changes in the pulsatory vacuole activity of Paramecium caudatum, highlighted dose dependent response by the test compound. The simplicity of handling this ciliate makes unicellular eukaryote, an alternative organism for the toxicity assessment of pollutants. The tests carried in this study are simple and fast, a bioassay that gives overall information about the physiological and cytotoxic effects of carbofuran to P. caudatum. Such bioassay tests using ciliates are more suitable for risk assessment of water quality, early detection of water pollution and possible role of ciliates as bioindicators and strategic tools in the bioremediation of water bodies. 相似文献
143.
Mohd Hafiz Mohd HazirAbdul Rashid Mohamed Shariff Mohd Din Amiruddin 《Industrial Crops and Products》2012,36(1):466-475
Non-destructive and real-time oil palm fresh fruit bunch (FFB) grading systems are of major exploratory concern for researchers in the oil palm industry. The objective is to reduce time, labour, costs, and most importantly, to increase the oil extraction rate, in order to achieve a good quality of palm oil at a more acceptable price. This research investigates the potential of flavonoids and anthocyanins as a predictor to classify the degree of oil palm FFB ripeness. This paper also discusses the relationship between these predictors and the ripeness categories period. One hundred and eighty oil palm FFB samples were collected from a private plantation in Malaysia, according to three maturity categories i.e., ripe, under-ripe, and over-ripe. Each sample was randomly scanned 10 times, both front and back using a hand-held Multiplex®3 multi-parameter fluorescence sensor. The results show that flavonoid and anthocyanin content decreased from immature to over mature oil palm FFBs. Overall, the relationship using Pearson's correlation between flavonoids and anthocyanins was r2 = 0.84 and the most outstanding relationship accuracy was at the over-ripe stage, at 90%. Statistical analysis using analysis of variance (ANOVA) and pair-wise testing proved that both predictors gave significance difference between under-ripe, ripe, and over-ripe maturity categories. This shows that both predictors can be good indicators to classify oil palm FFB. Classification analysis was performed by using both predictors together and separately through several methods. The highest overall classification accuracy was 87.7% using a Stochastic Gradient Boosting Trees model and with both predictors. The other classification methods used either independent or both predictors together and gave various results ranging from 50 to 85% accuracy. This research proves that flavonoids and anthocyanins can be used as predictors of oil palm maturity classification. 相似文献
144.
Nitrogen(N) use efficiency is usually less than 50%, and it remains a major problem in rice cultivation. Controlled release fertilizer(CRF) technology is one of the well-known efforts to overcome this problem. The efficiency of CRF, however, is very much dependent on the timing of nutrient release. This study was conducted to determine the precise time of N uptake by rice as a guideline to develop efficient CRF. Fertilizer N uptake by rice at different growth stages was investigated by using 15 N isotopic technique. Rice was planted in pots, with 15 N urea as N source at the rate of 120 kg/hm2. Potassium and phosphorus were applied at the same rate of 50 kg/hm2. Standard agronomic practices were employed throughout the growing periods. Rice plants were harvested every two weeks until maturation at the 14 th week and analyzed for total N and 15 N content. Nitrogen derived from fertilizer was calculated. Total N uptake in plants consistently increased until the 11 th week. After that, it started to plateau and finally declined. Moreover, N utilization by rice plants peaked at 50%, which occurred during the 11 th week after transplanting. N derived from fertilizer in rice plants were in the range of 18.7% to 40.0% in all plant tissues. The remaining N was derived from soil. Based on this study, N release from CRF should complete by the 11 th week after planting to ensure the maximum fertilizer N uptake by rice plants. Efficient CRF should contribute to higher N derived from fertilizer which also resulted in a higher total N uptake by rice plants, increasing the potential of rice to produce higher yield while at the same time of reducing loss. 相似文献
145.
146.
Water quality influences the presence of Streptococcus agalactiae in cage cultured red hybrid tilapia,Oreochromis niloticus × Oreochromis mossambicus 下载免费PDF全文
Mohammad Noor Azmai Amal Mohd Zamri Saad Abdullah Siti Zahrah Abd Rashid Zulkafli 《Aquaculture Research》2015,46(2):313-323
Attempts were made to identify the association between water quality parameters and the presence of Streptococcus agalactiae in cage cultured red hybrid tilapia, Oreochromis niloticus × O. mossambicus. Fish from commercial floating net cage‐culture systems in a river and lake were randomly sampled over a 24‐month period. Swabs from the brains, eyes and kidneys were streaked directly onto blood agar to isolate S. agalactiae. Water temperature, dissolved oxygen, pH, clarity, ammonia, nitrite, sulfide, rate of water flow and depth of water at sampling sites were measured at the same time of fish sampling. The prevalence of fish that were cultured positive to S. agalactiae was significantly higher in lake compared with river. The length and weight of the infected fish were between 9 and 33 cm, and between 20 and 760 g respectively. There was a significant and positive strong correlation between the presence of S. agalactiae and fish mortalities in lake. All water quality parameters showed significant differences between river and lake. However, only water temperature, clarity and pH of lake and the ammonia, temperature and dissolved oxygen in river showed significant correlation with the presence of S. agalactiae in the cultured fish. It was concluded that several unfavourable water quality in the fish farm influencing the presence of S. agalactiae in cultured red hybrid tilapia. 相似文献
147.
Nurul Shamsinah Mohd Suhaimi Rozeita Laboh Noni Ajam Kwai Lin Thong 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(1):13-26
A blood disease pathogenic strain, Ralstonia syzygii subspecies celebesensis was used to study the possible association of biofilm-forming bacteria with the development and severity of blood disease in banana plants. Therefore, the objective of this study was to determine the effects of mono-culture and co-culture inoculation of isolated biofilm-forming bacteria with the blood disease pathogen in banana pseudostems in glasshouse conditions. Putative biofilm-forming bacteria were isolated from an infected banana plant and were further identified using 16SrRNA sequencing. Four isolates, identified as Enterobacter hormaechei, Enterobacter cloacae, Kosakonia radicincitans and Klebsiella pneumoniae, were inoculated as a mono- and co-culture with R. syzygii subsp. celebesensis into 2 months old banana plants. The observation after the 8 weeks of post inoculation showed that plants which were co-inoculated with the pathogen and K. radicincitans, a biofilm-forming bacterium, were the most susceptible towards the infection. In contrast, plants under two treatments (which were co-inoculated with the pathogen and E. cloacae and the pathogen with E. hormaechei) were less susceptible towards the infection. This study revealed the antagonistic effects of two biofilm-forming strains which reduced the severity of infection caused by the pathogenic agent. Scanning electron micrographs of the cross section of plant rhizomes indicated the dissimilarity of adhesion and host colonization conditions of the pathogen in each infected plant from different treatments. 相似文献
148.
Md Lutfor Rahman Bablu Hira Mandal Shaheen M. Sarkar Nor Asiken Abdul Wahab Mashitah Mohd Yusoff Sazmal E. Arshad Baba Musta 《Fibers and Polymers》2016,17(4):521-532
A cellulose-graft-poly(methyl acrylate) was synthesized by free radical initiating process and the ester functional groups were converted into the hydroxamic acid ligand. The intermediate and final products are characterized by FT-IR, FE-SEM, HR-TEM and XPS technique. The pH of the solution acts as a key factor in achieving optical color signals of metalcomplexation. The reflectance spectra of the [Cu-ligand]n+ complex was found to be a highest absorbance at 99.8 % at pH 6 and it was increased upon increasing of Cu2+ ion concentrations and a broad peak at 700 nm was observed which indicated the charge transfer (π-π transition) metals-Cu complex. The adsorption capacity of copper was found to be superior (336 mg g?1) rather than other transition metals such as Fe3+, Co3+, Cr3+, Ni2+, Mn2+ and Zn2+ were 310, 295, 288, 250, 248 and 225 mg g-1, respectively at pH 6. The experimental data of all metal ions fitted significantly with the pseudo-second-order rate equation. The transition metal ions sorption onto ligand were well fitted with the Langmuir isotherm model (R2>0.99), which suggested that the cellulose-based adsorbent known as poly(hydroxamic acid) ligand surface is homogenous and monolayer. The reusability of the poly(hydroxamic acid) ligand was checked by the sorption/desorption process up to ten cycles without any significant loss in its original sensing and removal performances. 相似文献
149.
Malaysian Gelam honey has anti-inflammatory and antibacterial properties, a high antioxidant capacity, and free radical-scavenging activity. Lipopolysaccharide (LPS) stimulates immune cells to sequentially release early pro- and anti-inflammatory cytokines and induces the synthesis of several related enzymes. The aim of this study was to investigate the effect of the intravenous injection of honey in rats with LPS-induced endotoxemia. The results showed that after 4h of treatment, honey reduced cytokine (tumor necrosis factor-α, interleukins 1β, and 10) and NO levels and increased heme oxygenase-1 levels. After 24h, a decrease in cytokines and NO and an increase in HO-1 were seen in all groups, whereas a reduction in HMGB1 occurred only in the honey-treated groups. These results support the further examination of honey as a natural compound for the treatment of a wide range of inflammatory diseases. 相似文献
150.
Mohd Rafatullah Othman Sulaiman Rokiah Hashim Anees Ahmad 《Wood Science and Technology》2012,46(1-3):221-241
Meranti wood, an inexpensive material, has been utilized as an adsorbent for the removal of cadmium (II) from aqueous solutions. Various physico-chemical parameters such as equilibrium contact time, solution pH, initial metal ion concentration, and adsorbent dosage level were studied. Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherms were used to analyze the equilibrium data at different temperatures. The experimental data fitted well with the Langmuir adsorption isotherm, indicating the monolayer adsorption of the cadmium (II). The monolayer adsorption capacity of meranti wood for cadmium (II) was found to be 175.43, 163.93 and 153.84?mg/g at 30, 40, and 50°C, respectively. The thermodynamics of cadmium (II) adsorption on meranti wood indicates its spontaneous and exothermic nature. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model. The results indicated that the meranti wood could be an alternative for more costly adsorbents used for cadmium (II) removal. 相似文献