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81.
The reactivity of selected compounds in Lake Huron water was evaluated during ozone/hydrogen peroxide-based advanced oxidation process (AOP) and conventional treatment (coagulation?Csedimentation?Cfiltration). Elimination of these compounds via advanced oxidation and conventional treatment processes were strongly related to their molecular structures. Overall removal of target compounds was quite similar in effluents from both the AOP and the combined treatment process (AOP?+?conventional) with the exception of fluoxetine. Reaction rate constants for the decomposition of the target compounds were substantially higher during AOP compared to conventional treatment alone.  相似文献   
82.
This study was designed to determine the adequate copper (Cu) foliar spray concentration to correct Cu deficiency on barley (Hordeum vulgare L.) when grown in a calcareous soil. Five Cu foliar spray solution levels were tested (0% or control; 0.03%, 0.06%, 0.13%, and 0.33%). Copper was applied in the sulfate form at the early boot stage. The results showed that Cu flag leaf concentration was increased with the highest Cu application (0.33%), while Cu concentration in the grain was increased with a spray of 0.03%. An antagonism between Cu, Zn, and Fe leaf concentration was observed. Grain yield and harvest index showed a linear positive response to Cu foliar spray concentrations. A significant increase of 19.6% on grain yield was recorded with a foliar spray 0.33% of Cu.  相似文献   
83.
This report describes a protocol for the in vitro shoot induction and plant regeneration from epicotyl explants of Cassia angustifolia on Murashige and Skoog (MS) medium supplemented with 6-benzyladenine (BA), Kinetin and 2-iP (0.5–10.0 μM). MS medium supplemented with BA (5.0 μM) was the most effective in inducing adventitious shoots and growth. The highest rate of shoot multiplication was achieved on MS medium supplemented with BA (5.0 μM) and Indole-3-acetic acid (IAA, 1.0 μM). The nodal segments excised from the shoots regenerated from BA (5.0 μM) and IAA (1.0 μM) were used as explants for next three round of micropropagation. The number of shoots significantly increased at successive round of micropropagation. For rooting, MS medium supplemented with 2.0 μM indole-3-butyric acid proved to be better than that supplemented with IAA or α-naphthalene acetic acid. The in vitro raised plantlets with well developed shoot and roots were successfully established in earthen pots containing garden soil and were grown in greenhouse. About 52 plants (85 %) survived out of 60 plants transferred in garden soil.  相似文献   
84.
Tropical Animal Health and Production - Turkey coryza is a major respiratory disease caused by Bordetella avium (B. avium). It occurs in all ages of turkeys and is characterized by high morbidity...  相似文献   
85.
Indonesia is one of the most biodiverse countries in the world and a promising resource for novel natural compound producers. Actinomycetes produce about two thirds of all clinically used antibiotics. Thus, exploiting Indonesia’s microbial diversity for actinomycetes may lead to the discovery of novel antibiotics. A total of 422 actinomycete strains were isolated from three different unique areas in Indonesia and tested for their antimicrobial activity. Nine potent bioactive strains were prioritized for further drug screening approaches. The nine strains were cultivated in different solid and liquid media, and a combination of genome mining analysis and mass spectrometry (MS)-based molecular networking was employed to identify potential novel compounds. By correlating secondary metabolite gene cluster data with MS-based molecular networking results, we identified several gene cluster-encoded biosynthetic products from the nine strains, including naphthyridinomycin, amicetin, echinomycin, tirandamycin, antimycin, and desferrioxamine B. Moreover, 16 putative ion clusters and numerous gene clusters were detected that could not be associated with any known compound, indicating that the strains can produce novel secondary metabolites. Our results demonstrate that sampling of actinomycetes from unique and biodiversity-rich habitats, such as Indonesia, along with a combination of gene cluster networking and molecular networking approaches, accelerates natural product identification.  相似文献   
86.
The current study was conducted to evaluate the effects of gonadotropin-releasing hormone (GnRH) analogue (Receptal) injection on reproductive traits of fully mature layers hens (32 weeks) suffered from inactive ovaries. Ninety-six non-laying hens (TETRA-SL brown egg layers), selected from a commercial flock, with similar body weight, were randomly assigned to four groups (n = 24). Hens in the 1st group served as a control. Hens of the 2nd, 3rd and 4th groups were individually intramuscularly injected every 4 days with 50, 100 and 150 µl of Receptal solution, respectively, for two times. The results stated that the injection of Receptal induced the non-laying hens to produce eggs, but control birds did not produce eggs during the experimental period. The distance between pelvic bones and between the pelvic bone and keel bone of hens was significantly improved (p < .001) in groups received different GnRH levels compared with the control group. The best results were observed in the group injected with 100 µl Receptal. Levels of LH, FSH, oestrogen and progesterone hormones were significantly (p < .05) higher in Receptal-treated groups than in the control group. Hens injected with Receptal had an increase in ovary%, yellow follicles number, oviduct% and oviduct length (p < .001) compared with the control. It was concluded that treating inactive ovaries in non-laying hens with GnRH injections for two times, 4-day intervals, is an effective procedure for inducing egg production and useful in cost reduction in layer farms, and the group treated with 100 µl Receptal had the best results.  相似文献   
87.
A PCR-based protocol for the identification of genetically modified salmon carrying a growth hormone transgene was developed. Several primer pairs were examined, and the primers that gave consistent results were selected to conduct routine testing. Comparison among several DNA extraction procedures, as well as different buffer compositions, led to the adoption of TriZol as the method of choice. Low potassium and high magnesium chloride concentrations were very important in the overall success of the PCR reaction, whereas buffer pH, ranging from 8.3 to 9.2, had little impact on the amplification reaction. The optimal primer annealing temperature was 52 degrees C. Although fish muscle tissues were the primary source for DNA samples, detection of the transgene was also possible in bones, skin, fins, and other organs. No benefits were achieved by the addition of additives such as dimethyl sulfoxide and betaine to the PCR reaction. This optimized PCR method was used to identify all samples tested (61 samples and 17 controls) with 100% accuracy.  相似文献   
88.
Occurrence and distribution of organochlorine pesticides in the water of Lake Mariut, a brackish coastal Egyptian lake suffering from pollution, and their accumulation in the common fish Tilapia were studied. The major pesticides detected in the lake water were lindane, p,p′-DDE, o,p′-DDT, and p,p′-DDT. These compounds, except o,p′-DDT, were detected in the fish samples in exceedingly higher concentrations compared with those found in the lake water.  相似文献   
89.
Summary The temperature dependence of the NO production rate and the NO consumption rate constant was measured in an Egyptian soil, a soil from the Bavarian Forest, and a soil from the Donau valley, together with the temperature dependence of the potential rates of ammonium oxidation, nitrite oxidation, and denitrification, and the temperature dependence of the growth of NH inf4 sup+ -oxidizing, NO inf2 sup- -oxidizing, and NO inf3 sup- -reducing bacteria in most probable number assays. In the acidic Bavarian Forest soil, NO production was only stimulated by the addition of NO inf3 sup- but not NH inf4 sup+ . However, NO production showed no temperature optimum, indicating that it was due to chemical processes. Most probable numbers and potential activities of nitrifiers were very low. NO consumption, in contrast, showed a temperature optimum at 25°C, demonstrating that consumption and production of NO were regulated individually by the soil temperature. In the neutral, subtropical Egyptian soil, NO production was stimulated only by the addition of NH inf4 sup+ but not NO inf3 sup- . All activities and most probable numbers showed a temperature optimum at 25° or 30°C and exhibited apparent activation energies between 61 and 202 kJ mol-1. However, a few nitrifiers and denitrifiers were also able to grow at 8° or 50°C. Similar temperature characteristics were observed in the Donau valley soil, although it originated from a temperate region. In this soil NO production was stimulated by the addition of NH inf4 sup+ or of NO inf3 sup- . Both NO production and consumption were stimulated by drying and rewetting.  相似文献   
90.
Three incubation experiments were carried out to assess the effect of different levels of sludge, salinity and of different wetting and drying cycles on amidase and urease activity in a calcareous silt loam soil. Both amidase and urease activities were largely increased with the increase in the amount of sludge applied. The addition of NH4+ - N with sludge slightly reduced both activities. Addition of increasing amounts of a 1:1 NaCl: CaCl2 salt mixture increasingly reduced the soil activities of amidase and urease. This effect was less severe in sludge amended soil. The data also showed that drying of either unamended or sludge amended soil cause a marked drop in amidase and urease activity. Rewetting increased both enzyme activities.  相似文献   
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