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1.
Sci Rep ; 12(1): 5186, 2022 03 25.
Article in English | MEDLINE | ID: mdl-35338227

ABSTRACT

The current study focuses on water scarcity, water shortages, and inequal water allocation for downstream water users in the Balkhab River basin (BRB) in northern Afghanistan. The Soil and Water Assessment Tool (SWAT) was utilized to determine the hydrological process in the watershed and assess the water resource capacity. The model was calibrated and validated to ensure proper model setup for the entire watershed. The analysis of the current water management and allocation scheme indicated inadequate water distributions for the downstream irrigation canals. The current water allocation approach was modified based on crop water requirements and the available agricultural lands. A new irrigation scheme was proposed and included in the SWAT model that does not decrease upstream water allocation. The annual streamflow in the Balkhab River can supply the extra allocated water downstream without influencing the upstream water. Notably, a dam was proposed in the middle stream to store water during the winter and early spring seasons, as well as floodwater. The model outcomes showed that the existing annual streamflow in the river can fully support the irrigation of currently available land and an extra 18,470.6 ha of agricultural lands in the BRB. The results of this study can contribute to scientific evidence-based policy and decision-making processes for sustainable agricultural water resource management and flood control in the study region.


Subject(s)
Agricultural Irrigation , Soil , Afghanistan , Agricultural Irrigation/methods , Hydrology , Water
2.
J Asia Pac Biodivers ; 6(3): 391-396, 2013 Sep.
Article in English | MEDLINE | ID: mdl-32289034

ABSTRACT

In order to analyze the home range of feral cats residing in the surroundings of rural and suburban areas, we collected coordination information data from five feral cats. As a result of such research, 100% MCP was defined as minimum 31,500 and maximum 351,900, and 95% KR was defined as minimum 9,400 and maximum 502,800, 75% KR was defined as minimum 3,600 and maximum 126,900, and 50% MCP was defined as minimum 1,800 and maximum 51,700. The home range of feral cats was also analyzed during daytime and nighttime, and all five individuals showed a wider home range during the nighttime than daytime. The analysis of gender shows that the average home range of female feral cats is larger than the average of males. Meanwhile, the results of information data with wide-open areas such as farm land and terrace land on the river showed that the analyzed value was increased generally, and showed variable values depending on the gender and size of each individual feral cat.

3.
Environ Sci Technol ; 45(5): 1932-9, 2011 Mar 01.
Article in English | MEDLINE | ID: mdl-21288037

ABSTRACT

In the radioactive waste management, metal chloride wastes from a pyrochemical process is one of problematic wastes not directly applicable to a conventional solidification process. Different from a use of minerals or a specific phosphate glass for immobilizing radioactive waste salts, our research group applied an inorganic composite, SAP (SiO(2)-Al(2)O(3)-P(2)O(5)), to stabilize them by dechlorination. From this method, a unique wasteform composing of phosphate and silicate could be fabricated. This study described the characteristic of the wasteform on the morphology, chemical durability, and some physical properties. The wasteform has a unique "domain-matrix" structure which would be attributed to the incompatibility between silicate and phosphate glass. At higher amounts of chemical binder, "P-rich phase encapsulated by Si-rich phase" was a dominant morphology, but it was changed to be Si-rich phase encapsulated by P-rich phase at a lower amount of binder. The domain and subdomain size in the wasteform was about 0.5-2 µm and hundreds of nm, respectively. The chemical durability of wasteform was confirmed by various leaching test methods (PCT-A, ISO dynamic leaching test, and MCC-1). From the leaching tests, it was found that the P-rich phase had ten times lower leach-resistance than the Si-rich phase. The leach rates of Cs and Sr in the wasteform were about 10(-3)g/m(2)· day, and the leached fractions of them were about 0.04% and 0.06% at 357 days, respectively. Using this method, we could stabilize and solidify the waste salt to form a monolithic wasteform with good leach-resistance. Also, the decrease of waste volume by the dechlorination approach would be beneficial in the final disposal cost, compared with the present immobilization methods for waste salt.


Subject(s)
Phosphates/chemistry , Radioactive Waste/analysis , Silicates/chemistry , Uranium/chemistry , Waste Management/methods , Kinetics , Salts/chemistry
4.
Biochem Biophys Res Commun ; 376(2): 404-8, 2008 Nov 14.
Article in English | MEDLINE | ID: mdl-18789310

ABSTRACT

We investigated the molecular effect and signal pathway of icariin, a major flavonoid of Epimedium koreanum Nakai, on angiogenesis. Icariin stimulated in vitro endothelial cell proliferation, migration, and tubulogenesis, which are typical phenomena of angiogenesis, as well as increased in vivo angiogenesis. Icariin activated the angiogenic signal modulators, ERK, phosphatidylinositol 3-kinase (PI3K), Akt, and endothelial nitric oxide synthase (eNOS), and increased NO production, without affecting VEGF expression, indicating that icariin may directly stimulate angiogenesis. Icariin-induced ERK activation and angiogenic events were significantly inhibited by the MEK inhibitor PD98059, without affecting Akt and eNOS phosphorylation. The PI3K inhibitor Wortmannin suppressed icariin-mediated angiogenesis and Akt and eNOS activation without affecting ERK phosphorylation. Moreover, the NOS inhibitor NMA partially reduced the angiogenic activity of icariin. These results suggest that icariin stimulated angiogenesis by activating the MEK/ERK- and PI3K/Akt/eNOS-dependent signal pathways and may be a useful drug for angiogenic therapy.


Subject(s)
Angiogenesis Inducing Agents/pharmacology , Endothelial Cells/drug effects , Flavonoids/pharmacology , MAP Kinase Signaling System/drug effects , Neovascularization, Physiologic/drug effects , Endothelial Cells/enzymology , Endothelial Cells/physiology , Enzyme Inhibitors/pharmacology , Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors , Extracellular Signal-Regulated MAP Kinases/metabolism , Humans , MAP Kinase Kinase Kinases/antagonists & inhibitors , MAP Kinase Kinase Kinases/metabolism , Nitric Oxide Synthase Type III/antagonists & inhibitors , Nitric Oxide Synthase Type III/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide-3 Kinase Inhibitors , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/metabolism
5.
J Hazard Mater ; 160(2-3): 634-7, 2008 Dec 30.
Article in English | MEDLINE | ID: mdl-18440139

ABSTRACT

In this study, a vacuum distillation of a mixture of LiCl-KCl eutectic salt and rare-earth oxidative precipitates was performed to separate a pure LiCl-KCl eutectic salt from the mixture. Also, a dechlorination and oxidation of the rare-earth oxychlorides was carried out to stabilize a final waste form. The mixture was distilled under a range of 710-759.5Torr of a reduced pressure at a fixed heating rate of 4 degrees C/min and the LiCl-KCl eutectic salt was completely separated from the mixture. The required time for the salt distillation and the starting temperature for the salt vaporization were lowered with a reduction in the pressure. Dechlorination and oxidation of the rare-earth oxychlorides was completed at a temperature below 1300 degrees C and this was dependent on the partial pressure of O2. The rare-earth oxychlorides (NdOCl/PrOCl) were transformed to oxides (Nd2O3/PrO2) during the dechlorination and oxidation process. These results will be utilized to design a concept for a process for recycling the waste salt from an electrorefining process.


Subject(s)
Lithium Chloride/analysis , Metals, Rare Earth/chemistry , Potassium Chloride/analysis , Hypochlorous Acid/chemistry , Oxidation-Reduction , Temperature , X-Ray Diffraction
6.
Environ Sci Technol ; 42(24): 9357-62, 2008 Dec 15.
Article in English | MEDLINE | ID: mdl-19174916

ABSTRACT

The molten salt waste from the pyroprocess is one of the problematic wastes to directly apply a conventional process such as vitrification or ceramization. This study suggested a novel method using a reactive material for metal chlorides at a molten temperature of salt waste, and then converting them into manageable product at a high temperature. The inorganic composite, SAP (SiO2-Al2O3-P2O5), synthesized by a conventional sol-gel process has three or four distinctive domains that are bonded sequentially, Si-O-Si-O-A-O-P-O-P. The P-rich phase in the SAP composite is unstable for producing a series of reactive sites when in contact with a molten LiCl salt. After the reaction, metal aluminosilicate, metal aluminophosphate, metal phosphates and gaseous chlorines are generated. From this process, the volatile salt waste is stabilized and it is possible to apply a high temperature process. The reaction products were fabricated successfully by using a borosilicate glass with an arbitrary composition as a chemical binder. There was a low possibility for the valorization of radionuclides up to 1200 degrees C, based on the result of the thermo gravimetric analysis. The Cs and Sr leach rates by the PCT-A method were about 1 x 10(-3) g/(m2 day). For the final disposal of the problematic salt waste, this approach suggested the design concept of an effective stabilizer for metal chlorides and revealed the chemical route to the fabrication of monolithic wasteform by using a composite as an example. Using this method, we could obtain a higher disposal efficiency and lower waste volume, compared with the present immobilization methods.


Subject(s)
Aluminum Oxide/chemistry , Phosphorus Compounds/chemistry , Radioactive Waste , Salts/isolation & purification , Silicon Dioxide/chemistry , Chlorides/chemistry , Magnetic Resonance Spectroscopy , Metals/chemistry , Microscopy, Electron, Scanning , Salts/chemistry , Thermogravimetry , X-Ray Diffraction
7.
Health Phys ; 90(1): 42-55, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16340607

ABSTRACT

This paper describes a dynamic compartment model for evaluating the tritium level in agricultural plants after a short-term exposure to HTO vapor and its comparison with experimental results to test the predictive accuracy of the model. The model uses a time-dependent growth equation of a plant so that it can predict the contamination level of tritium depending on the stage of the growth of the plant, which is a major difference from some other compartment models using a constant crop yield. The model is able to calculate the time variable concentrations of the compartments representing the atmosphere, soil, and plants of four categories including leafy vegetables, root vegetables, grains, and tuber plants. Experimental results include the tissue free water tritium (TFWT) and the organically bound tritium (OBT) concentration of rice, soybean, cabbage, and radish exposed to HTO vapor for 1 h in the daytime at different growth stages. The model predictions showed that the model could simulate well not only the time-dependent tritium concentration of the plants but also the effect of the growth stage of the plant at the exposure time. Comparison of the model predictions with the experimental results suggested that the model could predict reasonably well the observed TFWT and OBT concentrations of the plants considered.


Subject(s)
Food Contamination, Radioactive , Plants, Edible/chemistry , Tritium/analysis , Agriculture , Volatilization , Water
8.
J Environ Radioact ; 76(3): 349-67, 2004.
Article in English | MEDLINE | ID: mdl-15261422

ABSTRACT

A dynamic compartment model has been studied to estimate the transfer of radionuclides deposited onto flooded rice-fields after an accidental release. In the model, a surface water compartment and a direct shoot-base absorption from the surface water to the rice-plant, which are major features discriminating the present model from the existing model, has been introduced to account for the flooded condition of rice-fields. The model has been applied to the deposition experiments of 137Cs on rice-fields that were performed at three different times to simulate the deposition before transplanting (May 2) and during the growth of the rice (June 1 and August 12), respectively. In the case of the deposition of May 2, the root-uptake is the most predominant process for transferring 137Cs to the rice-body and grain. When the radionuclide is applied just after transplanting (June 1), the activity of the body is controlled by the shoot-base absorption and the activity of the grain by the root-uptake. The deposition just before ear-emergence (August 12) shows that the shoot-base absorption contributes entirely to the increase of both the activities of the body and grain. The model prediction agrees within one or two factors with the experimental results obtained for a respective deposition experiment.


Subject(s)
Food Contamination , Models, Theoretical , Radioactive Hazard Release , Water Pollutants, Radioactive/analysis , Water Pollutants, Radioactive/pharmacokinetics , Cesium Radioisotopes/analysis , Disasters , Forecasting , Oryza , Plant Roots , Risk Assessment
9.
Exp Mol Med ; 36(6): 534-44, 2004 Dec 31.
Article in English | MEDLINE | ID: mdl-15665586

ABSTRACT

During chronic inflammatory response, mono- cytes/macrophages produce 92-kDa matrix metalloproteinase-9 (MMP-9), which may contribute to their extravasation, migration and tissue remodeling. Activation of peroxisome proliferator- activated factor receptor-g (PPAR-g) has been shown to inhibit MMP-9 activity. To evaluate whether ox-LDL, a PPAR-g activator, inhibits PMA-induced MMP-9 expression and activity, and if so, whether CD36 and PPAR-g are involved in this process, we investigated the effect of ox-LDL on MMP-9 expression and activity in PMA-activated human monocytic cell line U937. PMA-induced MMP-9 expression and activity were suppressed by the treatment with ox-LDL (50 mg/ml) or PPAR-g activators such as troglitazone (5 mM), ciglitazone (5 mM), and 15d- PGJ2 (1 mM) for 24 h. This ox-LDL or PPAR-g activator-mediated inhibition of MMP-9 activity was diminished by the pre-treatment of cells with a blocking antibody to CD36, or PGF2a (0.3 mM), which is a PPAR-g inhibitor, as well as overexpression of a dominant-negative form of CD36. Taken together, these results suggest that ox-LDL suppresses PMA-induced MMP-9 expression and activity through CD36-mediated activation of PPAR-g.


Subject(s)
CD36 Antigens/physiology , Lipoproteins, LDL/physiology , Matrix Metalloproteinase 9/metabolism , Monocytes/enzymology , PPAR gamma/metabolism , Prostaglandin D2/analogs & derivatives , Antibodies, Blocking/pharmacology , CD36 Antigens/immunology , Cells, Cultured , Chromans/pharmacology , Humans , Lipoproteins, LDL/pharmacology , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase Inhibitors , Monocytes/drug effects , Monocytes/metabolism , NF-kappa B/antagonists & inhibitors , Prostaglandin D2/pharmacology , RNA, Messenger/analysis , RNA, Messenger/metabolism , Tetradecanoylphorbol Acetate/antagonists & inhibitors , Tetradecanoylphorbol Acetate/pharmacology , Thiazolidinediones/pharmacology , Transcription, Genetic/drug effects , Troglitazone
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