45 research outputs found

    The effects of sowing time and depth on germination and seedling percentage of the Taurus Cedar (Cedrus libani A. Rich.)

    Get PDF
    The aim of this study is to determine the appropriate sowing time and depth in spring for Taurus Cedar (Cedrus libani A. Rich) in Turkey. The effects of sowing time and depth were determined with regard tothe germination rate of seedlings’ quality. The seeds were collected from Kapidag-Isparta, in Turkey, in 2003 and 2004. The seeds were sown at 6 different dates and 5 different depths under natural conditions without any pre-treatment in 2004 and 2005. The statistical approach was randomized block design with 3 replications and 100 seeds were sown for each replication. The 1000 seed weights and germination percentages of the seeds were determined under laboratory conditions before sowing inthe nursery. According to analysis of variance and Duncan’s test, in locations with appropriate soil conditions, seeds should be sown at 5 mm depth as soon as possible until the second half of February. The germination of 65% can be obtained from seeds sown under these conditions. High quality, bare root and one-year-old seedlings can be grown from approximately 55% of the seeds. Moreover, spring sowing should not take place after March 15th and at depths of more than 20 mm

    The effects of different pot length and growing media on seedling quality of Crimean juniper (Juniperus excelsa Bieb.)

    Get PDF
    The aim of this study was to determine appropriate pot length and growing medium for Crimean Juniper seedlings (Juniperus excelsa Bieb.), which will be used for afforestation of extreme areas. For this purpose, polyethylene pots of 11 cm width and 20, 25 and 30 cm lengths were used. As growing medium, 13 different treatments were used, containing different ratios of forest soil, pumice, creek sand and humus collected from the species’ natural forest environments. The experimental design was a randomized block with 3 replications under open field conditions. Some morphological properties of the seedlings, such as seedling height, root collar diameter, shoot and root fresh and dry weights and shoot/root ratios (fresh and dry weights) were measured on 1 + 0 year old seedlings. Statistical analyses indicated that when pot length increased, the seedling quality improved. The seedlings with the best quality in terms of the measured criteria can be grown in 11 cm x 30 cm pots. In respect to the growing media, 70% forest soil + 15% humus + 15% pumice or creek sand should be used

    Levels of paraoxonase and arylesterase activities and malondialdehyde in workers exposed to ionizing radiation

    No full text
    We examined levels of malondialdehyde (MDA) (an end-product of lipid peroxidation) and paraoxonase (PON1) (an antioxidant enzyme) activity and PON1 phenotypes in people who were exposed to ionizing radiation for different time periods and doses. A total of 78 individuals (mean age 34 7 years) were included in the study. Fifty-one of them were radiology workers whereas the control group was composed of 27 healthy volunteers who had never worked in a radiology-related job. Paraoxon was used as substrate for measurement of PON1 activity levels (basal and NaCl-stimulated). Phenylacetate was used as substrate for measurement of arylesterase activity levels. Cumulative levels of serum NaCl-stimulated PON1/arylesterase activities were utilized for phenotypic differentiation. In radiology workers, three different phenotypes were determined based on paraoxonase/arylesterase ratio. The ratios were 1.09 +/- 0.30 for AA (homozygote low activity); 2.91 +/- 1.07 for AB (heterozygote activity) and 4.97 +/- 1.21 for BB (homozygote high activity). There was a statistically meaningful negative correlation between serum MDA levels and PON1 activity levels in all phenotypes (p 5 years) radiation compared to controls. There was no statistically significant correlation between serum arylesterase activity and MDA levels in these subjects (r = -0.185, p > 0.05). PON1 activity levels were decreased whereas serum MDA levels were increased in individuals exposed to radiation for a long period. PON phenotypes of people employed in jobs which expose them to radiation should be determined and based on these findings they should be advised to avoid risk factors inducing oxidative stress, such as smoking, and to consume foods rich in vitamins and trace elements to increase their antioxidant capacity. Copyright (C) 2003 John Wiley Sons, Ltd.We examined levels of malondialdehyde (MDA) (an end-product of lipid peroxidation) and paraoxonase (PON1) (an antioxidant enzyme) activity and PON1 phenotypes in people who were exposed to ionizing radiation for different time periods and doses. A total of 78 individuals (mean age 34 +/- 7 years) were included in the study. Fifty-one of them were radiology workers whereas the control group was composed of 27 healthy volunteers who had never worked in a radiology-related job. Paraoxon was used as substrate for measurement of PON1 activity levels (basal and NaCl-stimulated). Phenylacetate was used as substrate for measurement of arylesterase activity levels. Cumulative levels of serum NaCl-stimulated PON1/arylesterase activities were utilized for phenotypic differentiation. In radiology workers, three different phenotypes were determined based on paraoxonase/arylesterase ratio. The ratios were 1.09 +/- 0.30 for AA (homozygote low activity); 2.91 +/- 1.07 for AB (heterozygote activity) and 4.97 +/- 1.21 for BB (homozygote high activity). There was a statistically meaningful negative correlation between serum MDA levels and PON1 activity levels in all phenotypes (p &lt; 0.05). PON1 activity levels were found to be 25-35% lower in people who were exposed to long-term ( &gt; 5 years) radiation compared to controls. There was no statistically significant correlation between serum arylesterase activity and MDA levels in these subjects (r = -0.185, p &gt; 0.05). PON1 activity levels were decreased whereas serum MDA levels were increased in individuals exposed to radiation for a long period. PON phenotypes of people employed in jobs which expose them to radiation should be determined and based on these findings they should be advised to avoid risk factors inducing oxidative stress, such as smoking, and to consume foods rich in vitamins and trace elements to increase their antioxidant capacity.</p

    A Congenital Arteriovenous Malformation Originating from the Aorta Locating in the Posterior Mediastinum

    No full text
    Vascular malformations located in the posterior mediastinum are extremely rare. Most of them are found coincidentally during routine examinations. Only a small percentage of these posterior mediastinal arteriovenous malformation cases may cause symptoms such as dyspnea due to compression of surrounding tissues. Radio logic imaging can be insufficient in some cases for differential diagnosis. Because of their vascular nature, diagnostic needle biopsy may have a high risk of bleeding. Open surgical resection is a safe treatment choice under many circumstances, and it helps the diagnosis as well. In this paper, a case of a 31-year-old male is presented with an incidentally diagnosed arteriovenous malformation, originating from the descending aorta and located in the posterior mediastinum
    corecore