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51.
17β-estradiol and testosterone are naturally occurring steroids that co-occur in poultry litter. The effects of litter on sorption of these hormones to soil are not known. Sorption isotherms were developed for C-labeled testosterone and H-labeled estradiol in a Cecil sandy clay loam with and without poultry litter addition. The effect of applying the hormones alone (single-sorbate) or together (multisorbate) was also investigated. C-testosterone sorption in soil increased from 2 to 48 h and remained relatively constant thereafter. H-estradiol sorption in soil was relatively constant from 2 to 24 h and then decreased to 72 h. These differences may reflect transformation of the parent hormones to products with different solid-phase affinity. The maximum sorption coefficient () in soil for C-testosterone (20.2 mL g) was similar to that for H-estradiol (19.6 mL g) in single-sorbate experiments. When hormones were applied together, sorption of both hormones in soil decreased, but the C-testosterone (12.5 mL g) was nearly twice as large as the H-estradiol (7.4 mL g). We propose this resulted from competition between the hormones and their transformation products for sorption sites, with C-testosterone and its expected transformation product (androstenedione) being better competitors than H-estradiol and its expected transformation product (estrone). When poultry litter was mixed with soil, sorption increased for H-estradiol but decreased for C-testosterone. This may have been because poultry litter slowed the transformation of parent hormones. Our results show that poultry litter could have important effects on the mobility of estradiol and testosterone.  相似文献   
52.
This paper presents a forecasting study of municipal solid waste generation (MSWG) rate and potential of its recyclable components in Kuala Lumpur (KL), the capital city of Malaysia. The generation rates and composition of solid wastes of various classes such as street cleansing, landscape and garden, industrial and constructional, institutional, residential and commercial are analyzed. The past and present trends are studied and extrapolated for the coming years using Microsoft office 2003 Excel spreadsheet assuming a linear behavior. The study shows that increased solid waste generation of KL is alarming. For instance, the amount of daily residential SWG is found to be about 1.62 kg/capita; with the national average at 0.8–0.9 kg/capita and is expected to be increasing linearly, reaching to 2.23 kg/capita by 2024. This figure seems reasonable for an urban developing area like KL city. It is also found that, food (organic) waste is the major recyclable component followed by mix paper and mix plastics. Along with estimated population growth and their business activities, it has been observed that the city is still lacking in terms of efficient waste treatment technology, sufficient fund, public awareness, maintaining the established norms of industrial waste treatment etc. Hence it is recommended that the concerned authority (DBKL) shall view this issue seriously.  相似文献   
53.
The effect of Dimethoate, Carbaryl and Permethrin on the activities of liver L-tryptophan 2,3-dioxygenase (total-, holo-, and apo-forms) and pyridoxal phosphokinase of male mice was investigated. Dimethoate inhibited both enzyme systems after single and repeated dose treatment; except the dioxygenase holo-enzyme after repeated doses. Single dose of Carbaryl treatment inhibited the pyridoxal phosphokinase, total and holo-enzyme of L-tryptophan dioxygenase. However, the repeated dose treatment do not affect both enzyme systems. Permethrin inhibited only total-, holo- and apo-enzymes of L-tryptophan dioxygenase whereas repeated administration has no significant effect on both enzymes. The data indicate that these insecticides may induce abnormal tryptophan metabolism through which some endogenous bladder carcinogens are formed.  相似文献   
54.
Environmental Science and Pollution Research - Globally, climate change is an alarming threat to the livestock industry. Such changes in the climate can also adversely affect the returns of...  相似文献   
55.
56.
In vivo chronic effect of dimethoate and deltamethrin on rabbits   总被引:1,自引:0,他引:1  
The in vivo effect of dimethoate and deltamethrin on body and organ weights, serum proteins and on plasma acetylcholinesterase (AChE), aromatic esterase and ATPase were examined in growing male rabbits throughout five months period. Both compounds had no significant effect on body weight; however, adrenal, testis & pituitary weights decreased (P less than 0.01); the liver and spleen weights increased (P less than 0.01) in a dose dependent manner. Serum total proteins and globulin decreased (P less than 0.01) in a dose dependent trend, while serum albumin was not greatly affected. AChE activity was increased (P less than 0.01) after 1 month of treatment with the two doses of dimethoate and deltamethrin; thereafter, AChE activity showed 40% inhibition of the control level. The activity of aromatic esterase increased markedly after the first month, then declined gradually until the fifth month. High dose of dimethoate markedly inhibited this enzyme particularly after the 5th month of treatment. Both doses of deltamethrin increased ATPase activity after the first month of treatment, then the ATPase activity was normal. Dimethoate inhibited ATPase particularly at the end of treatment in a dose dependent manner.  相似文献   
57.
Yacob S  Hassan MA  Shirai Y  Wakisaka M  Subash S 《Chemosphere》2005,59(11):1575-1581
Anthropogenic release of greenhouse gases, especially CO2 and CH4 has been recognized as one of the main causes of global warming. Several measures under the Kyoto Protocol 1997 have been drawn up to reduce the greenhouse gases emission. One of the measures is Clean Development Mechanisms (CDM) that was created to enable developed countries to cooperate with developing countries in emission reduction activities. In Malaysia, palm oil industry particularly from palm oil mill effluent (POME) anaerobic treatment has been identified as an important source of CH4. However, there is no study to quantify the actual CH4 emission from the commercial scale wastewater treatment facility. Hence, this paper shall address the CH4 emission from the open digesting tanks in Felda Serting Hilir Palm Oil Mill. CH4 emission pattern was recorded for 52 weeks from 3600 m3 open digesting tanks. The findings indicated that the CH4 content was between 13.5% and 49.0% which was lower than the value of 65% reported earlier. The biogas flow rate ranged between 0.8 l min−1 m−2 and 9.8 l min−1 m−2. Total CH4 emission per open digesting tank was 518.9 kg day−1. Relationships between CH4 emission and total carbon removal and POME discharged were also discussed. Fluctuation of biogas production was observed throughout the studies as a result of seasonal oil palm cropping, mill activities, variation of POME quality and quantity discharged from the mill. Thus only through long-term field measurement CH4 emission can be accurately estimated.  相似文献   
58.
On exposure to sunlight or photolysis at λ >300nm, the dechlorination of a polychlorinated biphenyl mixture (Aroclor 1254) in the H donor alcohol 2-propanol under neutral conditions is enhanced by the presence of the photosensitizer hydroquinone. Dechlorination is strongly promoted by an increasingly aqueous solvent (1:1 water:alcohol) and by maintaining neutral conditions (pH 7.0 buffer) both in the presence and absence of sensitizer. Atmospheric oxygen (continuous aeration) retards the hydroquinone induced dechlorination less than the direct photolysis process.  相似文献   
59.
Napier grass (Pennisetum purpureum) is the most important fodder crop in smallholder dairy production systems in East Africa, characterized by small zero-grazing units. It is also an important trap crop used in the management of cereal stemborers in maize in the region. However, production of Napier grass in the region is severely constrained by Napier stunt disease. The etiology of the disease is known to be a phytoplasma, 16SrXI strain. However, the putative insect vector was yet unknown. We sampled and identified five leafhopper and three planthopper species associated with Napier grass and used them as candidates in pathogen transmission experiments. Polymerase chain reaction (PCR), based on the highly conserved 16S gene, primed by P1/P6-R16F2n/R16R2 nested primer sets was used to diagnose phytoplasma on test plants and insects, before and after transmission experiments. Healthy plants were exposed for 60 days to insects that had fed on diseased plants and acquired phytoplasma. The plants were then incubated for another 30 days. Nested PCR analyses showed that 58.3% of plants exposed to Recilia banda Kramer (Hemiptera: Cicadellidae) were positive for phytoplasma and developed characteristic stunt disease symptoms while 60% of R. banda insect samples were similarly phytoplasma positive. We compared the nucleotide sequences of the phytoplasma isolated from R. banda, Napier grass on which these insects were fed, and Napier grass infected by R. banda, and found them to be virtually identical. The results confirm that R. banda transmits Napier stunt phytoplasma in western Kenya, and may be the key vector of Napier stunt disease in this region.  相似文献   
60.
The intense interest in desertification and climate change has stimulated detailed studies of temperature records in many areas of the world. In this investigation, the temperature records from the Middle East region are analyzed over the period 1950–1990. Results reveal a linear, statistically significant temperature increase of 0.07 °C/decade over the 41-year period. An analysis of spatial controls on these temperature changes reveals a warming effect associated with both overgrazing and the degree of human-induced desertification. The results of this study are consistent with theoretical and empirical studies predicting and demonstrating a warming signal associated with these land surface changes in the world's dryland areas.  相似文献   
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