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81.
Remediation of Lead Contaminated Soils by Stabilization/Solidification   总被引:2,自引:0,他引:2  
Most available remediation technologies for treatment of heavymetal contaminated soils are very expensive and result in residues requiring further treatment. Stabilization/solidification (immobilization) techniques however, which aredesigned to decrease leaching potential of heavy metals from soil by addition of chemical additives, provide very cost-effective solutions for heavy metal contaminated soils. Thisstudy investigates the most efficient additive for immobilization of lead. To achieve this goal, several leachingexperiments were conducted for mixtures of different additives(lime, activated carbon, clay, zeolite, sand and cement) withartificially Pb contaminated (spiked) soil samples in accordancewith the Toxicity Characterization Leaching Procedure (TCLP) developed by U.S. EPA. Results showed that among the additivestried, activated carbon, clay, zeolite and sand are not very efficient for Pb immobilization. On the other hand, lime andcement are significantly effective in Pb immobilization with 88% efficiency at 1:21 lime:soil ratio and 99% efficiency at1:15 cement:soil ratio, respectively.  相似文献   
82.
Triploidy in fertilized eggs of Melicertus kerathurus was induced by cold (8, 10, 12°C) and heat (34, 36, 38°C) shock for different duration times (2, 4 and 8 min) after 10 min of post spawning. The best individual treatment produced 64.5% triploid nauplii in cold shock application at a temperature of 10°C for a duration of 8 min. Temperature did not have significant effect (P > 0.05) on triploid rate but duration time had a significant effect (P < 0.05) for individual cold or heat shock. This study demonstrates that because of a wide variety of effective parameters, it is essential to optimize shock conditions for each species strain at each location.  相似文献   
83.
84.
The effects of Tomato spotted wilt virus (TSWV) on yield and quality of tomato fruits were studied from May through November of 2004 at the Experimental Field of the Agricultural Faculty of Ondokuz Mayis University, in Samsun province, Turkey. TSWV caused 42.1% and 95.5% reduction in yield and marketable value of tomato, respectively. TSWV infection in tomato crop caused significant (P < 0.05) reductions in weight, total number, width and length of the fruits in infected plants. Reductions in yield-contributing parameters were 26.61% in weight, 20.18% in number, 10.94% in width and 11.93% in length of fruits. It is difficult to estimate the actual yield loss and influence levels of TSWV in the field. Economic data are scarce, but in the present study it was estimated that the yield loss due to TSWV in tomatoes was approximately $0.9 million in Samsun, Turkey.  相似文献   
85.

The Anatolian ground squirrel (Spermophilus xanthoprymnus) is a typical example of true mammalian hibernators. In order to adapt to extreme external and internal environments during hibernation, they lower their body temperatures, heart rates and oxygen consumption; however, pathological events such as ischemia and ventricular fibrillation do not occur in their cardiovascular systems. During the hibernation, maintenance of cardiac function is very important for survival of ground squirrels. Natriuretic peptides (NPs) are key factors in the regulation of cardiovascular hemostasis. Since NPs’ role on the protection of heart during hibernation are less clear, the aim of this study was to investigate dynamic changes in NPs content in the cardiac chambers and to reveal the possible role of NPs on establishing cardiac function in ground squirrel during hibernation using immunohistochemistry. The immunohistochemical results indicate that cardiac NP expressions in atrial and ventricular cardiomyocytes were different from each other and were sex-independent. ANP and BNP were expressed in a chamber-dependent manner in female and male squirrel hearts. Furthermore, cardiac NPs expression levels in hibernation period were lower than those at the pre-hibernation period. During prehibernation period, ANP, BNP and CNP were expressed in the white and beige adipocytes of epicardial adipose tissue (EAT); while during hibernation period, the brown adipocytes of EAT were positive for BNP and CNP. These data suggest that the hibernation-dependent reduction in levels of NPs, particularly ANP, in cardiac chambers and EAT may be associated with low heart rate and oxygen consumption during hibernation. However, further studies are needed to better delineate the roles of NPs during the hibernation.

  相似文献   
86.
Tropical Animal Health and Production - Rift valley fever (RVF), a vector-borne zoonotic disease, is caused by a phlebovirus (family Bunyaviridae). The virus was initially characterized...  相似文献   
87.
Field experiments were carried out in the 2004 and 2005 growing seasons on drip irrigated dwarf green beans (Phaseolus vulgaris, humilis). Soil water content (SWC), spectral reflectance and yield were monitored. Based on these data crop evapotranspiration (ETc), soil water deficit index (SWDI), water use efficiency (WUE) and four separate spectral indexes were calculated. In order to determine use opportunities of spectral indexes for estimation of yield, SWDI and WUE, some statistical analyzes were made. Results showed that spectral indexes could be used for monitoring of yield, SWDI and WUE. Especially, Soil Adjusted Vegetation Index (SAVI) had the highest correlations with all three of the parameters. The estimation procedure which was given in this study has a potential use either during, or at the end of the growing season. Estimated values of WUE and SWDI were 3.2 (kg m?3) and 0.12, respectively, through SAVI and the given procedure, indicates the optimal water use and yield conditions for dwarf green beans. At this situation, probably ETc was 580 mm and yield was 25.5 t ha?1.  相似文献   
88.
The treated seeds (control, KNO3 and hydropriming) of sunflower (Helianthus annuus L.) cultivar Sanbro were evaluated at germination and seedling growth for tolerance to salt (NaCl) and drought conditions induced by PEG-6000 at the same water potentials of 0.0, −0.3, −0.6, −0.9 and −1.2 MPa. Electrical conductivity (EC) values of the NaCl solutions were 0.0, 6.5, 12.7, 18.4 and 23.5 dS m−1, respectively. The objective of the study was to determine factors responsible for germination and early seedling growth due to salt toxicity or osmotic effect and to optimize the best priming treatment for these stress conditions.

Results revealed that germination delayed in both solutions, having variable germination with different priming treatments. Germination, root and shoot length were higher but mean germination time and abnormal germination percentage were lower in NaCl than PEG at the same water potential. Seeds were able to germinate at all concentrations of NaCl but no seed germination was observed at −1.2 MPa of PEG treatments. NaCl had less inhibitor effect on seedling growth than the germination. It was concluded that inhibition of germination at the same water potential of NaCl and PEG resulted from osmotic effect rather than salt toxicity. Hydropriming increased germination and seedling growth under salt and drought stresses.  相似文献   

89.
Along with sulfate turpentine, the essential oils obtained by steam distillation from nine plant species naturally grown in Turkish forests were tested at three different concentrations to evaluate their effectiveness against the larvae of pine processionary moth (Thaumetopoea pityocampa Schiff). The results indicated that the essential oils from the nine species and sulfate turpentine were effective against the larvae of T pityocampa. The most effective essential oil in the control of the larvae was steam-distilled wood turpentine, followed by thyme herb oil, juniper berry oil, laurel leaf oil, lavender flower oil, eucalyptus leaf oil, lavender leaf oil, cypress berry oil, essential oil of styrax and sulfate turpentine, respectively, in terms of mean mortality time. It is therefore feasible to use these essential oils as environment-friendly insecticides in the control of T pityocampa.  相似文献   
90.
A case of aspergillosis in a broiler breeder flock having respiratory and nervous system problems caused by Aspergillus fumigatus and Aspergillus niger is documented. Dyspnea, hyperpnea, blindness, torticollis, lack of equilibrium, and stunting were observed clinically. On postmortem examination of the affected birds, white to yellow caseous nodules were observed on lungs, thoracic air sacs, eyes, and cerebellum. Histopathologic examination of lungs and cerebellum revealed classic granulomatous inflammation and cerebellar lesions, necrotic meningoencephalitis, respectively. No lesions were noted in the cerebrum histopathologically. Aspergillus hyphae were observed in stained sections prepared from lesioned organs. Fungal spores and branched septate hyphae were observed in direct microscopy. Aspergillus fumigatus and A. niger were isolated from the inoculations prepared from the suspensions of organs showing lesions.  相似文献   
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