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Bahram Falahatkar Konrad Dabrowski Murat Arslan & Jacques Rinchard 《Aquaculture Research》2006,37(8):834-841
This study was conducted to examine the effects of different forms and concentrations of ascorbic acid (vitamin C), and different enrichment times (24 and 48 h post ovulation) on egg, embryo and alevin ascorbate concentrations and survival of rainbow trout (enrichment was at the ova stage). In experiments 1 and 2, fertilized eggs were immersed in water containing ascorbate at 0 (control), 100, 1000 mg L?1 l ‐ascorbic acid (AA) and 2000 mg L?1 l ‐ascorbyl monophosphate (AP). In experiment 3, 0 (control), 500 and 1000 mg L?1 AA neutralized (N) with NaOH, 1000 mg L?1 AA non‐neutralized (NN), 1000 and 2000 mg L?1 AP immersions were used. The mean total ascorbic acid (TAA) and dehydroascorbic acid (DHA) concentrations were measured before fertilization, at 3 and 24 h after fertilization, at the eyed stage, and in hatched alevins. We observed significant differences in TAA concentration at different immersion levels at 3 and 24 h after fertilization. Survival decreased significantly depending on the level of vitamin C, pH of the solutions and immersion time. We suggest that when broodstock rainbow trout do not have enough vitamin C in their ovaries, immersion of eggs in 1000 mg L?1 of neutralized AA may be useful. 相似文献
3.
Faisal Zulfiqar Suzanne E. Allaire Nudrat Aisha Akram Ana Méndez Adnan Younis Arslan Masood Peerzada 《Journal of plant nutrition》2019,42(11-12):1386-1401
Plant production in potting substrates provides maximum profit on the applied inputs, and hence, directly improving the socio-economic condition of the grower/nurserymen. The main challenge in this industry is sourcing of materials for their potting substrates. Peat and perlite have been widely preferred materials. However, recently higher prices, more restrictive legislation of many countries and wetland ecosystem destruction through its extraction has limited peat use. Nowadays, producers focus towards peat alternatives that provide good performance, are readily available, inexpensive and environment friendly to attain sustainability in potted plant production. In an effort to grasp sustainability during the last few decades, many industrial and agricultural waste materials were reviewed for their use in potting substrates. In these studies, the major focus remained on material characterization, neglecting their economics, technical aspects and environmental impacts. Thus, switching from peat and perlite to alternatives requires material exploration. In the present review, we summarize a clearer and practical approach for substituting different materials especially biochar to fulfill the need of modern potting substrate industry. Biochar has the potential to sustain the substrate production on a long-term basis. 相似文献
4.
Dr. S. H. Arslan C. P. Mackenzie R. Brown J. T. Baxter 《Veterinary research communications》1983,6(1):51-58
The stage of hair growth which predominated in dogs not affected with hypothyroidism appeared to be breed-dependent. For example, in boxers, Labradors and collies, the resting stage (telogen) predominated, whereas in West Highland White terriers and cairn terriers the active stage (anagen) predominated. However, even in pet dogs kept mainly indoors, the proportion of hairs in anagen tended to increase during the winter months.In dogs affected with hypothyroidism, the proportion of hairs in anagen or telogen in members of a particular breed was the same as in the normal dogs of the breed. From this, it appeared that breed was more influential than hypothyroidism in determining the predominant phase of hair growth. 相似文献
5.
Sumaira Qutab Rizwan Rasheed M. Arslan Ashraf Iqbal Hussain Nudrat Aisha Akram 《Archives of Agronomy and Soil Science》2017,63(13):1900-1911
The effects of selenium (Se) cadmium (Cd) interactions on plant growth and metabolism are not fully clear. In the present study, we assessed whether Se could alleviate the toxic effects of Cd on growth and metabolism of maize. Seeds of maize variety FH-985 were sown in pots filled with sand treated with CdCl2 (0, 50 and 100 µM) and Se (0, 2 and 4 mg L?1) through Hoagland’s nutrient solution. Low Se (2 mg L?1) increased germination percentage and rate, while high Se (4 mg L?1) increased fresh and dry biomass under Cd stress. Interestingly, all Se concentrations were effective in alleviating the toxic effects of Cd on photosynthetic pigments, whereas higher Se mitigated the Cd-induced oxidative stress and increased flavonoids both in the shoots and roots while phenolics in the roots. The results demonstrated that root zone Se altered tissue-specific primary metabolism in maize. Furthermore, low Se mitigated the Cd-induced decrease in total proteins in the root. Overall, Se-mediated decrease in the oxidative stress in the shoots while increase of secondary metabolites in the roots helped the plants to grow faster at early growth stage and caused increase in the biomass under different Cd regimes. 相似文献
6.
A 4-year study of parasitoids attackingChrysoperla carnea (Stephens) in the cotton fields of Çukurova, Turkey, revealed the activities of three principal taxa:Telenomus sp. nr.suvae attacks the eggs ofC. carnea: Catolaccus sp. andBaryscapus sp. are larval and pupal parasitoids, respectively. In general, percent egg parasitism increased starting from the second half of June and into July, then decreased until the beginning of August before rising again at the end of growing season. During the early season, weekly parasitism was found to be as high as 94%. Overall, seasonal egg parasitism varied between 13.6% and 62.0% among all study sites. According to the results of a one-year field study at Hac?ali, total larval and pupal parasitism was found to be 12.5% and 55.6%, respectively. Therefore, different factors influencing the effectiveness of the generalist predatorC. carnea against cotton pests, and the differential effects of cotton treatments on both host and parasitoids, need to be evaluated. 相似文献
7.
Nanotechnology creates a new challenge for materials characterization because device properties now depend on size and shape as much as they depend on the traditional parameters of structure and composition. Here we show that Z-contrast tomography in the scanning transmission electron microscope has been developed to determine the complete three-dimensional size and shape of embedded structures with a resolution of approximately 1 cubic nanometer. The results from a tin/silicon quantum dot system show that the positions of the quantum dots and their size, shape, structure, and formation mechanism can be determined directly. These methods are applicable to any system, providing a unique and versatile three-dimensional visualization tool. 相似文献
8.
Nurcan Erbil Zehra Tugba Murathan Mehmet Arslan Ahmet Ilcim Bilge Sayin 《Erwerbs-Obstbau》2018,60(3):203-209
The pear (Pyrus spp.) is one of the most important fruits consumed in daily life. The aim of this study was to determine the total phenolic and ascorbic acid contents, as well as the antimicrobial, antioxidant, and antimutagenic activities, of various pear cultivars. The fruits of five pear (Pyrus communis L.) cultivars (‘Deveci’, ‘Kizil’, ‘Egirsah’, ‘Gugum’, and ‘Banda’) were used in this study. It was determined that the peel and pulp of the ‘Kizil’ pear had the highest total phenolic content (402.5?mg/100?g and 215.2?mg/100?g, respectively), while those of the ‘Banda’ pear had the lowest total phenolic content (326?mg/100?g and 126.1?mg/100?g, respectively). Additionally, the ‘Kizil’ pear showed the highest antioxidant capacity in the 2,2’-azino-bis(3-ethylbenzothiazoline-6-6-sulphonic acid) (ABTS) and ferric-reducing ability assay (FRAP) (1.72 μmol TE/g FW and 161.25?μmol Fe II/g FW, respectively) and the highest ascorbic acid content (16.02?mg/100?g). The ‘Banda’ pear showed the highest antibacterial activity against the test bacteria. However, none of the pear extracts displayed antifungal activity. While all doses of the ‘Kizil’, ‘Gugum’, and ‘Banda’ pear extracts used in this study, except 80?μL/plate, exhibited antimutagenic activities, only the lowest dose (10?μL/plate) of the ‘Deveci’ pear extract showed the antimutagenic activity against induced mutagenesis in the Salmonella typhimurium TA 98 strain. Consequently, the five Turkish pear cultivars used in this study exhibited different levels of antimicrobial, antioxidant, and antimutagenic activities. 相似文献
9.
Nitrogen mineralisation in soils of various forest sites (pine plantation, natural and thinned oak) at Uluda? University campus in Bursa, Turkey was investigated continuously over a year by the field incubation method. Net nitrogen mineralisation and nitrification rates varied depending on sampling dates. Although nitrogen mineralisation and nitrification rates increased in the spring and summer months, there was no seasonal variation in the soils of the examined forests. Annual net nitrate (NO3?–N) accumulation in the upper soil layer (0–5 cm) was higher in Oak I and Oak II (14 kg ha y?1 and 12 kg ha y?1) than in the pine plantation (8 kg ha y?1). While annual net NO3?–N accumulation (0–5 cm) varied between the oak forests (possibly due to forest management practices), annual net Nmin values were similar in these forests. No significant correlation was found between the examined soil parameters and net nitrification and mineralisation rates in the soils (P > 0.05). These results indicate that tree species and forest management practices play important roles in N cycling in forest ecosystems. 相似文献
10.