A number of HPLC methods have been approved for the determination of rifampicin, but no references involved the assay of related substances of rifampicin. In the present paper, a reversed-phase liquid chromatographic ...A number of HPLC methods have been approved for the determination of rifampicin, but no references involved the assay of related substances of rifampicin. In the present paper, a reversed-phase liquid chromatographic method for the determination of related substances of rifampicin is developed and validated. Rifampicin and its related substances, including rifamycin SV, rifampicin N-oxide and 3-formylrifamycin SV were separated using a Zorbax Eclipse C8, 250×4.6 mm(i.d), 5 μm column by isocratic elution at a flow rate of 1 mL·min -1. The detector was set at 254 nm. The mobile phase is a mixture of methanol-acetonitrile -0.075 mol·L -1 monopotassium phosphate -1.0 mol·L -1 citric acid (31:31:35:3, v/v). The method validation included accuracy, precision, linearity, sensitivity and stability. All results are shown to be acceptable.展开更多
Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for t...Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy.展开更多
AIM: To evaluate the hepatoprotective effect of garlic on liver injury induced by isoniazid (INH) and rifarnpicin (RIF). METHODS: Wistar rats weighing 150-200 g were treated orally with 50 mg/kg of INH and RIF d...AIM: To evaluate the hepatoprotective effect of garlic on liver injury induced by isoniazid (INH) and rifarnpicin (RIF). METHODS: Wistar rats weighing 150-200 g were treated orally with 50 mg/kg of INH and RIF daily each for 28 d. For hepatoprotective studies, 0.25 g/kg per day of freshly prepared garlic hornogenate was administered orally half an hour before the INH+RIF doses. Serum alanine arninotransferase (AIT), aspartate aminotransferase (AST) and bilirubin were estimated on d 0, 14, 21, and 28 in all the rats. Histological analysis was carried out to assess the injury to the liver. Lipid peroxidation (1PO) as a marker of oxidative stress and non-protein thiols (glutathione) for antioxidant levels were measured in liver hornogenate. RESULTS: The treatment of rats with INH+RIF (50 mg/kg per day each) induced hepatotoxicity in all the treated animals as judged by elevated serum ALT, AST, and bilirubin levels, presence of focal hepatocytic necrosis (6/8) and portal triaditis (8/8). Garlic simultaneously administered at a dose of 0.25 g/kg per day prevented the induction of histopathological injuries in INH+RIF co-treated animals, except in 4 animals, which showed only moderate portal triaditis. The histological changes correlated with oxidative stress in INH+RIF treated animals. The group which received 0.25 g/kg per day garlic hornogenate along with INH+RIF showed higher levels of glutathione (P〈0.05) and low levels of 1PO (P〈 0.05) as compared to INH+RIF treated group. CONCLUSION: Freshly prepared garlic homogenate protects against INH+RIF-induced liver injury in experimental animal model.展开更多
AIM: To evaluate and compare the hepatoprotective and immunomodulatory effects of Curcuma longa (CL), Ocimum sanctum (OS), Tinospora cordifolia (TC) and Zizyphus mauritiana (ZM) on liver injury and immunosuppression i...AIM: To evaluate and compare the hepatoprotective and immunomodulatory effects of Curcuma longa (CL), Ocimum sanctum (OS), Tinospora cordifolia (TC) and Zizyphus mauritiana (ZM) on liver injury and immunosuppression induced by Isoniazid (INH), Rifampicin (RIF) and Pyrazinamide (PZA). METHODS: Duncan Hartley guinea pigs, weighing 700-1050 g, were treated orally with 50 mg/kg of INH, 100 mg/kg of RIF and 300 mg/Kg of PZA for 21-d. 200 mg/kg (bw) of each herb crude extract was administered to the herb control group and 2-h previous to INH + RIF + PZA (AKT) doses to the Herb + AKT groups. Serum alanine aminotransferase (ALT), aspertate aminotransferase (AST) bilirubin and Alkaline Phosphatase (ALP) were assessed on d 0 and 21 in all the groups. Phagocytic % (P%), Phagocytic Index (PI) and Chemotactic Index (CI) were also measured as immunologic parameters. Histological analysis was carried out to assess injury to the liver. RESULTS: The AKT treated control group showed hepatotoxicity as judged by elevated serum AST 5-fold, AST/ALT ratio 4-fold, ALP 2-fold and hepatological changes, such as focal necrosis, portal triaditis and steatosis. Immune function was suppressed as judged by decreased P% (51.67 ?1.68 vs 40.61 ?1.28, P < 0.01), PI (2.0725±0.05 vs 0.61±0.05, P < 0.001) and CI (1.8525±0.04 vs 0.695±0.07, P < 0.001). All four herb treated groups showed normal liver histology, enzyme levels and increased P%, while PI and CI were enhanced in the TC and ZM treated groups, respectively. CL + AKT, TC + AKT and ZM + AKT showed nearly normal histology with minimal inflammation and microvesicular steatosis, while OS + AKT showed partial protection. Hepatotoxicity was prevented by restricting the rise of AST by 2-fold in CL + AKT and TC + AKT groups and by 3-fold in OS + AKT and ZM + AKT groups, AST/ALT by 2-fold and ALP to normal levels in all four groups. All four herb + AKT groups showed normal to enhanced neutrophil function. CONCLUSION: All four herbs showed hepatoprotective potential and prevented immunosuppression. CL and TC showed the highest hepatoprotective activity, while TC and ZM showed strong immunostimulatory activity.展开更多
AIM, To study the role of N-acetylcysteine (NAC) as a protective agent in rifampicin (RMP)-induced oxidative hepatic injury of young rats. METHODS: Hepatic injury was produced by giving 50mg/kg body weight/day of...AIM, To study the role of N-acetylcysteine (NAC) as a protective agent in rifampicin (RMP)-induced oxidative hepatic injury of young rats. METHODS: Hepatic injury was produced by giving 50mg/kg body weight/day of RMP for 3 wk. A dose of NAC (100mg/kg body weight/day) was given in combination with RMP intraperitoneally. Analysis of lipid peroxidation, thiol levels, cytochrome P4se, superoxide dismutase (SOD), catalase, glutathione peroxidase, reductase and transferase were estimated in liver along with the body weight, liver weight and histological observations. RESULTS: RMP exposure resulted in no change in body and liver weight while antioxidative enzymes were altered but the non protein thiol (GSH) status was well preserved. Cytochrome P450 system and peroxidation of lipids were induced by RMP exposure. Partial protection was observed with NAC against RMP-induced changes in liver, which was evidenced from the prevention of increase in lipid peroxidation and the reduction in SOD and catalase enzyme levels. CONCLUSION. NAC protects young rats against RMP- induced oxidative hepatic injury.展开更多
[Objective] The purpose of the study is to breed Micromonospora car- bonacea highly producing antibiotics and then to improve the antibiotic production. [Method] Sodium Nitrite mutagenesis, combined with rifampicin re...[Objective] The purpose of the study is to breed Micromonospora car- bonacea highly producing antibiotics and then to improve the antibiotic production. [Method] Sodium Nitrite mutagenesis, combined with rifampicin resistance screening, was used in mutation breeding of M. carbonacea highly producing antibiotics from the strain of M. carbonacea JXNU-I. [Result] The overproducing strain JXNU-1-16- Y65 was screened with the production of antibiotics 266.05% more than that of the original strain. [Conclusion] The effectiveness of sodium nitrite mutation in breeding microorganisms highly producing antibiotic was proved, and the study may lay the foundation on further development and application of the antibiotic from M. car- bonacea JXNU-1.展开更多
Based on the steady-state solution of finite-state birth and death process, the principle of line configuration for shared multi-channel system is analyzed. Call congestion ratio equation and channel utilization ratio...Based on the steady-state solution of finite-state birth and death process, the principle of line configuration for shared multi-channel system is analyzed. Call congestion ratio equation and channel utilization ratio equation are deduced, and visualized data analysis is presented. The analy-sis indicates that, calculated with the proposed equations, the overestimate for call congestion ratio and channel utilization ratio can be rectified, and thereby the cost of channels can be saved by 2000 in a small system.With MATLAB programming, line configuration methods are provided. In order to generally and intuitively show the dynamic running of the system, and to analyze,promote and improve it, the system is simulated using M/M/n/n/m queuing model and Monte-Carlo method. In addition, the simulation validates the correctness of the theoretical analysis and optimizing configuration method.展开更多
In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the...In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the balance between supply and demand. The two surface water resources, Gargar and Merdjet Sidi Abed dams, do not satisfy the requirements of agriculture water. According to the National Office of the Irrigation and Drainage data, the quantity of allocated water is never distributed; the difference between allocated water and drop water can also exceed 20%, and then, another problem of management is that the water losses in the distribution can reach 20% again. The shortage irrigation water resource allocated has constrained the farmers to use groundwater. The chemical analysis of 56 simples to this water showed a significant chemical diversity in the compositions. There is a high salinity risk (C3 class) or very high risk (C4 class) of soil salinisation. A space chart distribution to the EC water probability to exceed 2.25 dS/m interpolated by the indicator kriging method showed that 78% of the groundwater surface presents a significant probability to exceed this limit. The average value of the SAR (sodium adsorption ratio) is lower than 10 that indicates a moderate risk of sodisation. This observation is in contradiction with the high values of the SAR measured in the soil solution. The approach of residual alkalinity (RSC) shows that a good number of drillings analyzed presents a positive sign RSC (RSC 〉 0). This water presents a real danger of sodisation. They have a low salinity, which, for a farmer, does not present any danger.展开更多
We present the application of Support Vector Machine (SVM) for the prediction of blast induced ground vibration by taking into consideration of maximum charge per delay and distance between blast face to monitoring po...We present the application of Support Vector Machine (SVM) for the prediction of blast induced ground vibration by taking into consideration of maximum charge per delay and distance between blast face to monitoring point. To investigate the suitability of this approach, the predictions by SVM have been compared with conventional predictor equations. Blast vibration study was carried out at Magnesite mine of Pithoragarh, India. Total 170 blast vibrations data sets were recorded at different strate-gic and vulnerable locations in and around to mine. Out of 170 data sets, 150 were used for the training of the SVM network as well as to determine site constants of different conventional predictor equations, whereas, 20 new randomly selected data sets were used to compare the prediction capability of SVM network with conventional predictor equations. Results were compared based on Co-efficient of Determination (CoD) and Mean Absolute Error (MAE) between monitored and predicted values of Peak Particle Veloc-ity (PPV). It was found that SVM gives closer values of predicted PPV as compared to conventional predictor equations. The coef-ficient of determination between measured and predicted PPV by SVM was 0.955, whereas it was 0.262, 0.163, 0.337 and 0.232 by USBM, Langefors-Kihlstrom, Ambraseys-Hendron and Bureau of Indian Standard equations, respectively. The MAE for PPV was 11.13 by SVM, whereas it was 0.973, 1.088, 0.939 and 1.292 by USBM, Langefors-Kihlstrom, Ambraseys-Hendron and Bureau of Indian Standard equations respectively.展开更多
A practical adaptive turbo coded modulation (TuCM) scheme was proposed and its adaptive method was described. With some hardware considerations, a suboptimal optimization algorithm that the number of fading regions is...A practical adaptive turbo coded modulation (TuCM) scheme was proposed and its adaptive method was described. With some hardware considerations, a suboptimal optimization algorithm that the number of fading regions is variable was put forward. Furthermore, the cutoff fade depth of power adaptation was modified to reduce the interruption probability. The results show that the proposed adaptive TuCM comes within 3 dB of Rayleigh fading channel capacity, and exhibits about 3 dB power gain relative to the conventional adaptive trellis-coded modulation (TCM), and is easy to realize by hardware.展开更多
This study investigated the regional differences of China′s urban land expansion from the late 1980s to the year of 2008, based on the spatio-temporal analysis of CLCD (China′s land cover/land use database) datasets...This study investigated the regional differences of China′s urban land expansion from the late 1980s to the year of 2008, based on the spatio-temporal analysis of CLCD (China′s land cover/land use database) datasets which were mainly produced from remote sensing imagery data. A newly defined urbanization level index (UI), based on urban land area, is proposed to describe Chinese urban expansion process at 1 kilometer, provincial, regional, and na-tional scales, together with the absolute urban expansion index (UEa) and the relative urbanization expansion index (UEr). The results indicate that the percentages of total land area occupied by urban in the late 1980s, 1995, 2000, 2005, and 2008 were approximately 0.25%, 0.32%, 0.33%, 0.43% and 0.52% of China′s total land area, respectively. Between the late 1980s and 2008, the total urban expansion in the mainland of China was 2.645 × 104 km2, resulting in an annual urban expansion area of about 1322.7 km2/yr, with the UEr of 111.9%. This study also finds that there has been an obvious spatial gradient of urbanization ratio running from the east coast to the west inland, and the urbanization gaps among different regions have persisted over the past two decades. The study also reveals obvious temporal varia-tions of the urbanization rates. There was very little urban growth during the period of 1995-2000 due to the governmental policy factors.展开更多
In the Sanjiang Plain,Northeast China,the natural wetland is undergoing a rapid conversion into agricultural land,which has resulted in drastic ecological changes in the region. To investigate the effects of different...In the Sanjiang Plain,Northeast China,the natural wetland is undergoing a rapid conversion into agricultural land,which has resulted in drastic ecological changes in the region. To investigate the effects of different land uses on soil labile organic carbon,soils of Calamagrostis angustifolia wetland,Carex lasiocarpa wetland,dry farmland,paddy field,forest land and abandoned cultivated land were collected for measuring the contents of soil microbial biomass carbon (MBC),dissolved organic carbon (DOC),readily oxidizable carbon (ROC) and carbohydrate carbon (CHC). The results show that soil organic carbon contents follow the order: Carex lasiocarpa wetland>Calamagrostis angustifolia wetland>forest land>paddy field>dry farmland. The contents of MBC and DOC in Calamagrostis angustifolia and Carex lasiocarpa wetlands are significantly higher than those in other land use types. The contents of CHC and ROC are the highest in Calamagrostis angustifolia wetland and the lowest in dry farmland. The contents of all the labile organic carbon increase along with the years of abandonment of cultivated land. The ratios of MBC,DOC and ROC to SOC also follow the order: Carex lasiocarpa wetland>Calamagrostis angustifolia wetland>forest land>paddy field>dry farmland,while the ratio of CHC to SOC is paddy field>forest field>Carex lasiocarpa wetland>Carex lasiocarpa wetland>dry farmland. When natural wetlands were cultivated,the activity of soil organic carbon tends to reduce in some extent due to the disappearance of heterotrophic environment and the reduction of vegetation residue. Thus,the abandonment of cultivated land is an effective way for restoring soil organic carbon.展开更多
AIM: To study the sensitivity of gastric smooth muscle to C-type natriuretic peptide (CNP) in streptozotocin (STZ)-induced diabetic rats. METHODS: The spontaneous contraction of a gastric smooth muscle strip was recor...AIM: To study the sensitivity of gastric smooth muscle to C-type natriuretic peptide (CNP) in streptozotocin (STZ)-induced diabetic rats. METHODS: The spontaneous contraction of a gastric smooth muscle strip was recorded by using physiological methods in rats. The expressions of CNP and natriuretic peptide receptor-B (NPR-B) in gastric tissue were examined by using immunohistochemistry techniques in the diabetic rat. RESULTS: At 4 wk after injection of STZ and vehicle, the frequency of spontaneous contraction of gastric smooth muscle was significantly reduced in diabetic rats, and the frequency was decreased from 3.10 ± 0.14 cycle/min in controls to 2.23 ± 0.13 cycle/min (n = 8, P < 0.01). However, the amplitude of spontaneous contraction was not significant different from the normal rat. CNP significantly inhibited spontaneous contraction of gastric smooth muscle in normal and diabetic rats, but the inhibitory effect was significantly potentiated in the diabetic rats. The amplitudes of spontaneous contraction were suppressed by 75.15% ± 0.71% and 58.92% ± 1.32% while the frequencies were decreased by 53.33% ± 2.03% and 26.95% ± 2.82% in diabetic and normal rats, respectively (n = 8, P < 0.01). The expression of CNP in gastric tissue was not changed in diabetic rats, however the expression of NPR-B was significantly increased in diabetic rats, and the staining indexes of NPR-B were 30.67 ± 1.59 and 17.63 ± 1.49 in diabetic and normal rat, respectively (n = 8, P < 0.01).CONCLUSION: The results suggest that CNP induced an inhibitory effect on spontaneous contraction of gastric smooth muscle, potentiated in diabetic rat via up-regulation of the natriuretic peptides-NPR-B-particulate guanylyl cyclase-cyclic GMP signal pathway.展开更多
This research reports on potentiality in the solar chimney as an exhaust ventilation device through a hypothetical statement that convenient weather conditions exist on sub-humid warm climate to enhance the performanc...This research reports on potentiality in the solar chimney as an exhaust ventilation device through a hypothetical statement that convenient weather conditions exist on sub-humid warm climate to enhance the performance ofa SC (solar chimney), in order to increase ventilation to dissipate metabolic heat from inhabitants of airtight buildings. The methodology used in this research integrates the use of simplified mathematical models that predict in a semi-empirical way a potential volume flow through estimation of kinetic power generation, by natural circulation and stack effect in a typical covered-plate air solar collector. The study was carried out during the warm month of April, an important warm season for Colima, where the prevailing wind is about 6.8 m/s, the average temperature of maximums and minimums oscillates between 15.4℃and 34.4 ℃ with average relative humidity of 65% according to national weather service. A scale model of the SC was installed on environmental chambers. The results showed that this device is capable of generating ventilation conditions around light breeze parameters near between 0.6 m/s and 1.5 m/s width, a better performance at day in 45% approximately than the night values, making ventilation rates up 0.24 ACH (air changes per hour) as average air change rate.展开更多
The Miyun Reservoir is the most important water source for Beijing Municipality, the capital of China with a population of more than 12 million. In recent decades, the inflow to the reservoir has shown a decreasing tr...The Miyun Reservoir is the most important water source for Beijing Municipality, the capital of China with a population of more than 12 million. In recent decades, the inflow to the reservoir has shown a decreasing trend, which has seriously threatened water use in Beijing. In order to analyze the influents of land use and cover change (LUCC) upon inflow to Miyun Reservoir, terrain and land use information from remote sensing were utilized with a revised evapotranspiration estimation formula; a water loss model under conditions of human impacts was introduced; and a distributed monthly water balance model was established and applied to the Chaobai River Basin controlled by the Miyun Reservoir. The model simulation suggested that not only the impact of land cover change on evapotranspiration, but also the extra water loss caused by human activities, such as the water and soil conservation development projects should be considered. Although these development projects were of great benefit to human and ecological protection, they could reallocate water resources in time and space, and in a sense thereby influence the stream flow.展开更多
文摘A number of HPLC methods have been approved for the determination of rifampicin, but no references involved the assay of related substances of rifampicin. In the present paper, a reversed-phase liquid chromatographic method for the determination of related substances of rifampicin is developed and validated. Rifampicin and its related substances, including rifamycin SV, rifampicin N-oxide and 3-formylrifamycin SV were separated using a Zorbax Eclipse C8, 250×4.6 mm(i.d), 5 μm column by isocratic elution at a flow rate of 1 mL·min -1. The detector was set at 254 nm. The mobile phase is a mixture of methanol-acetonitrile -0.075 mol·L -1 monopotassium phosphate -1.0 mol·L -1 citric acid (31:31:35:3, v/v). The method validation included accuracy, precision, linearity, sensitivity and stability. All results are shown to be acceptable.
文摘Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy.
基金Supported by the Indian Council of Medical Research,New Delhi,India,No.45/39/2002-PHA/BMS
文摘AIM: To evaluate the hepatoprotective effect of garlic on liver injury induced by isoniazid (INH) and rifarnpicin (RIF). METHODS: Wistar rats weighing 150-200 g were treated orally with 50 mg/kg of INH and RIF daily each for 28 d. For hepatoprotective studies, 0.25 g/kg per day of freshly prepared garlic hornogenate was administered orally half an hour before the INH+RIF doses. Serum alanine arninotransferase (AIT), aspartate aminotransferase (AST) and bilirubin were estimated on d 0, 14, 21, and 28 in all the rats. Histological analysis was carried out to assess the injury to the liver. Lipid peroxidation (1PO) as a marker of oxidative stress and non-protein thiols (glutathione) for antioxidant levels were measured in liver hornogenate. RESULTS: The treatment of rats with INH+RIF (50 mg/kg per day each) induced hepatotoxicity in all the treated animals as judged by elevated serum ALT, AST, and bilirubin levels, presence of focal hepatocytic necrosis (6/8) and portal triaditis (8/8). Garlic simultaneously administered at a dose of 0.25 g/kg per day prevented the induction of histopathological injuries in INH+RIF co-treated animals, except in 4 animals, which showed only moderate portal triaditis. The histological changes correlated with oxidative stress in INH+RIF treated animals. The group which received 0.25 g/kg per day garlic hornogenate along with INH+RIF showed higher levels of glutathione (P〈0.05) and low levels of 1PO (P〈 0.05) as compared to INH+RIF treated group. CONCLUSION: Freshly prepared garlic homogenate protects against INH+RIF-induced liver injury in experimental animal model.
文摘AIM: To evaluate and compare the hepatoprotective and immunomodulatory effects of Curcuma longa (CL), Ocimum sanctum (OS), Tinospora cordifolia (TC) and Zizyphus mauritiana (ZM) on liver injury and immunosuppression induced by Isoniazid (INH), Rifampicin (RIF) and Pyrazinamide (PZA). METHODS: Duncan Hartley guinea pigs, weighing 700-1050 g, were treated orally with 50 mg/kg of INH, 100 mg/kg of RIF and 300 mg/Kg of PZA for 21-d. 200 mg/kg (bw) of each herb crude extract was administered to the herb control group and 2-h previous to INH + RIF + PZA (AKT) doses to the Herb + AKT groups. Serum alanine aminotransferase (ALT), aspertate aminotransferase (AST) bilirubin and Alkaline Phosphatase (ALP) were assessed on d 0 and 21 in all the groups. Phagocytic % (P%), Phagocytic Index (PI) and Chemotactic Index (CI) were also measured as immunologic parameters. Histological analysis was carried out to assess injury to the liver. RESULTS: The AKT treated control group showed hepatotoxicity as judged by elevated serum AST 5-fold, AST/ALT ratio 4-fold, ALP 2-fold and hepatological changes, such as focal necrosis, portal triaditis and steatosis. Immune function was suppressed as judged by decreased P% (51.67 ?1.68 vs 40.61 ?1.28, P < 0.01), PI (2.0725±0.05 vs 0.61±0.05, P < 0.001) and CI (1.8525±0.04 vs 0.695±0.07, P < 0.001). All four herb treated groups showed normal liver histology, enzyme levels and increased P%, while PI and CI were enhanced in the TC and ZM treated groups, respectively. CL + AKT, TC + AKT and ZM + AKT showed nearly normal histology with minimal inflammation and microvesicular steatosis, while OS + AKT showed partial protection. Hepatotoxicity was prevented by restricting the rise of AST by 2-fold in CL + AKT and TC + AKT groups and by 3-fold in OS + AKT and ZM + AKT groups, AST/ALT by 2-fold and ALP to normal levels in all four groups. All four herb + AKT groups showed normal to enhanced neutrophil function. CONCLUSION: All four herbs showed hepatoprotective potential and prevented immunosuppression. CL and TC showed the highest hepatoprotective activity, while TC and ZM showed strong immunostimulatory activity.
基金Supported ty Department of Science and Technology,Changdigarh, India
文摘AIM, To study the role of N-acetylcysteine (NAC) as a protective agent in rifampicin (RMP)-induced oxidative hepatic injury of young rats. METHODS: Hepatic injury was produced by giving 50mg/kg body weight/day of RMP for 3 wk. A dose of NAC (100mg/kg body weight/day) was given in combination with RMP intraperitoneally. Analysis of lipid peroxidation, thiol levels, cytochrome P4se, superoxide dismutase (SOD), catalase, glutathione peroxidase, reductase and transferase were estimated in liver along with the body weight, liver weight and histological observations. RESULTS: RMP exposure resulted in no change in body and liver weight while antioxidative enzymes were altered but the non protein thiol (GSH) status was well preserved. Cytochrome P450 system and peroxidation of lipids were induced by RMP exposure. Partial protection was observed with NAC against RMP-induced changes in liver, which was evidenced from the prevention of increase in lipid peroxidation and the reduction in SOD and catalase enzyme levels. CONCLUSION. NAC protects young rats against RMP- induced oxidative hepatic injury.
基金Supported by Science and Technology Planning Project of Jiangxi Province of China(20112BBF60026)~~
文摘[Objective] The purpose of the study is to breed Micromonospora car- bonacea highly producing antibiotics and then to improve the antibiotic production. [Method] Sodium Nitrite mutagenesis, combined with rifampicin resistance screening, was used in mutation breeding of M. carbonacea highly producing antibiotics from the strain of M. carbonacea JXNU-I. [Result] The overproducing strain JXNU-1-16- Y65 was screened with the production of antibiotics 266.05% more than that of the original strain. [Conclusion] The effectiveness of sodium nitrite mutation in breeding microorganisms highly producing antibiotic was proved, and the study may lay the foundation on further development and application of the antibiotic from M. car- bonacea JXNU-1.
文摘Based on the steady-state solution of finite-state birth and death process, the principle of line configuration for shared multi-channel system is analyzed. Call congestion ratio equation and channel utilization ratio equation are deduced, and visualized data analysis is presented. The analy-sis indicates that, calculated with the proposed equations, the overestimate for call congestion ratio and channel utilization ratio can be rectified, and thereby the cost of channels can be saved by 2000 in a small system.With MATLAB programming, line configuration methods are provided. In order to generally and intuitively show the dynamic running of the system, and to analyze,promote and improve it, the system is simulated using M/M/n/n/m queuing model and Monte-Carlo method. In addition, the simulation validates the correctness of the theoretical analysis and optimizing configuration method.
文摘In the Lower Cheliff Plain (northwestern of Algeria), the waters resources are limited; the adoption of a rational approach in the management of irrigation water in the irrigated perimeter poses an inequality in the balance between supply and demand. The two surface water resources, Gargar and Merdjet Sidi Abed dams, do not satisfy the requirements of agriculture water. According to the National Office of the Irrigation and Drainage data, the quantity of allocated water is never distributed; the difference between allocated water and drop water can also exceed 20%, and then, another problem of management is that the water losses in the distribution can reach 20% again. The shortage irrigation water resource allocated has constrained the farmers to use groundwater. The chemical analysis of 56 simples to this water showed a significant chemical diversity in the compositions. There is a high salinity risk (C3 class) or very high risk (C4 class) of soil salinisation. A space chart distribution to the EC water probability to exceed 2.25 dS/m interpolated by the indicator kriging method showed that 78% of the groundwater surface presents a significant probability to exceed this limit. The average value of the SAR (sodium adsorption ratio) is lower than 10 that indicates a moderate risk of sodisation. This observation is in contradiction with the high values of the SAR measured in the soil solution. The approach of residual alkalinity (RSC) shows that a good number of drillings analyzed presents a positive sign RSC (RSC 〉 0). This water presents a real danger of sodisation. They have a low salinity, which, for a farmer, does not present any danger.
文摘We present the application of Support Vector Machine (SVM) for the prediction of blast induced ground vibration by taking into consideration of maximum charge per delay and distance between blast face to monitoring point. To investigate the suitability of this approach, the predictions by SVM have been compared with conventional predictor equations. Blast vibration study was carried out at Magnesite mine of Pithoragarh, India. Total 170 blast vibrations data sets were recorded at different strate-gic and vulnerable locations in and around to mine. Out of 170 data sets, 150 were used for the training of the SVM network as well as to determine site constants of different conventional predictor equations, whereas, 20 new randomly selected data sets were used to compare the prediction capability of SVM network with conventional predictor equations. Results were compared based on Co-efficient of Determination (CoD) and Mean Absolute Error (MAE) between monitored and predicted values of Peak Particle Veloc-ity (PPV). It was found that SVM gives closer values of predicted PPV as compared to conventional predictor equations. The coef-ficient of determination between measured and predicted PPV by SVM was 0.955, whereas it was 0.262, 0.163, 0.337 and 0.232 by USBM, Langefors-Kihlstrom, Ambraseys-Hendron and Bureau of Indian Standard equations, respectively. The MAE for PPV was 11.13 by SVM, whereas it was 0.973, 1.088, 0.939 and 1.292 by USBM, Langefors-Kihlstrom, Ambraseys-Hendron and Bureau of Indian Standard equations respectively.
基金National Natural Science Foundation ofChina (60 0 72 0 2 8) High Technology Research and Developm entProgram (863 ) of China (2 0 0 1AA12 10 3 1)
文摘A practical adaptive turbo coded modulation (TuCM) scheme was proposed and its adaptive method was described. With some hardware considerations, a suboptimal optimization algorithm that the number of fading regions is variable was put forward. Furthermore, the cutoff fade depth of power adaptation was modified to reduce the interruption probability. The results show that the proposed adaptive TuCM comes within 3 dB of Rayleigh fading channel capacity, and exhibits about 3 dB power gain relative to the conventional adaptive trellis-coded modulation (TCM), and is easy to realize by hardware.
基金Under the auspices of National Basic Research Program of China (No. 2010CB950900)National Natural Science Foundation of China (No. 40971223)Knowledge Innovation Programs of Chinese Academy of Sciences (No. KZCX2-EW-306)
文摘This study investigated the regional differences of China′s urban land expansion from the late 1980s to the year of 2008, based on the spatio-temporal analysis of CLCD (China′s land cover/land use database) datasets which were mainly produced from remote sensing imagery data. A newly defined urbanization level index (UI), based on urban land area, is proposed to describe Chinese urban expansion process at 1 kilometer, provincial, regional, and na-tional scales, together with the absolute urban expansion index (UEa) and the relative urbanization expansion index (UEr). The results indicate that the percentages of total land area occupied by urban in the late 1980s, 1995, 2000, 2005, and 2008 were approximately 0.25%, 0.32%, 0.33%, 0.43% and 0.52% of China′s total land area, respectively. Between the late 1980s and 2008, the total urban expansion in the mainland of China was 2.645 × 104 km2, resulting in an annual urban expansion area of about 1322.7 km2/yr, with the UEr of 111.9%. This study also finds that there has been an obvious spatial gradient of urbanization ratio running from the east coast to the west inland, and the urbanization gaps among different regions have persisted over the past two decades. The study also reveals obvious temporal varia-tions of the urbanization rates. There was very little urban growth during the period of 1995-2000 due to the governmental policy factors.
基金Under the auspices of National Natural Science Foundation of China (No. 30470340)
文摘In the Sanjiang Plain,Northeast China,the natural wetland is undergoing a rapid conversion into agricultural land,which has resulted in drastic ecological changes in the region. To investigate the effects of different land uses on soil labile organic carbon,soils of Calamagrostis angustifolia wetland,Carex lasiocarpa wetland,dry farmland,paddy field,forest land and abandoned cultivated land were collected for measuring the contents of soil microbial biomass carbon (MBC),dissolved organic carbon (DOC),readily oxidizable carbon (ROC) and carbohydrate carbon (CHC). The results show that soil organic carbon contents follow the order: Carex lasiocarpa wetland>Calamagrostis angustifolia wetland>forest land>paddy field>dry farmland. The contents of MBC and DOC in Calamagrostis angustifolia and Carex lasiocarpa wetlands are significantly higher than those in other land use types. The contents of CHC and ROC are the highest in Calamagrostis angustifolia wetland and the lowest in dry farmland. The contents of all the labile organic carbon increase along with the years of abandonment of cultivated land. The ratios of MBC,DOC and ROC to SOC also follow the order: Carex lasiocarpa wetland>Calamagrostis angustifolia wetland>forest land>paddy field>dry farmland,while the ratio of CHC to SOC is paddy field>forest field>Carex lasiocarpa wetland>Carex lasiocarpa wetland>dry farmland. When natural wetlands were cultivated,the activity of soil organic carbon tends to reduce in some extent due to the disappearance of heterotrophic environment and the reduction of vegetation residue. Thus,the abandonment of cultivated land is an effective way for restoring soil organic carbon.
基金Supported by The National Natural Science Foundation of China, No. 30760068
文摘AIM: To study the sensitivity of gastric smooth muscle to C-type natriuretic peptide (CNP) in streptozotocin (STZ)-induced diabetic rats. METHODS: The spontaneous contraction of a gastric smooth muscle strip was recorded by using physiological methods in rats. The expressions of CNP and natriuretic peptide receptor-B (NPR-B) in gastric tissue were examined by using immunohistochemistry techniques in the diabetic rat. RESULTS: At 4 wk after injection of STZ and vehicle, the frequency of spontaneous contraction of gastric smooth muscle was significantly reduced in diabetic rats, and the frequency was decreased from 3.10 ± 0.14 cycle/min in controls to 2.23 ± 0.13 cycle/min (n = 8, P < 0.01). However, the amplitude of spontaneous contraction was not significant different from the normal rat. CNP significantly inhibited spontaneous contraction of gastric smooth muscle in normal and diabetic rats, but the inhibitory effect was significantly potentiated in the diabetic rats. The amplitudes of spontaneous contraction were suppressed by 75.15% ± 0.71% and 58.92% ± 1.32% while the frequencies were decreased by 53.33% ± 2.03% and 26.95% ± 2.82% in diabetic and normal rats, respectively (n = 8, P < 0.01). The expression of CNP in gastric tissue was not changed in diabetic rats, however the expression of NPR-B was significantly increased in diabetic rats, and the staining indexes of NPR-B were 30.67 ± 1.59 and 17.63 ± 1.49 in diabetic and normal rat, respectively (n = 8, P < 0.01).CONCLUSION: The results suggest that CNP induced an inhibitory effect on spontaneous contraction of gastric smooth muscle, potentiated in diabetic rat via up-regulation of the natriuretic peptides-NPR-B-particulate guanylyl cyclase-cyclic GMP signal pathway.
文摘This research reports on potentiality in the solar chimney as an exhaust ventilation device through a hypothetical statement that convenient weather conditions exist on sub-humid warm climate to enhance the performance ofa SC (solar chimney), in order to increase ventilation to dissipate metabolic heat from inhabitants of airtight buildings. The methodology used in this research integrates the use of simplified mathematical models that predict in a semi-empirical way a potential volume flow through estimation of kinetic power generation, by natural circulation and stack effect in a typical covered-plate air solar collector. The study was carried out during the warm month of April, an important warm season for Colima, where the prevailing wind is about 6.8 m/s, the average temperature of maximums and minimums oscillates between 15.4℃and 34.4 ℃ with average relative humidity of 65% according to national weather service. A scale model of the SC was installed on environmental chambers. The results showed that this device is capable of generating ventilation conditions around light breeze parameters near between 0.6 m/s and 1.5 m/s width, a better performance at day in 45% approximately than the night values, making ventilation rates up 0.24 ACH (air changes per hour) as average air change rate.
基金supported by the Knowledge Innovation Key Project of Chinese Academy of Sciences (Nos. CX10G-E01-08 andKZCX2-SW-317) and the National Natural Science Foundation of China (No. 50279049)
文摘The Miyun Reservoir is the most important water source for Beijing Municipality, the capital of China with a population of more than 12 million. In recent decades, the inflow to the reservoir has shown a decreasing trend, which has seriously threatened water use in Beijing. In order to analyze the influents of land use and cover change (LUCC) upon inflow to Miyun Reservoir, terrain and land use information from remote sensing were utilized with a revised evapotranspiration estimation formula; a water loss model under conditions of human impacts was introduced; and a distributed monthly water balance model was established and applied to the Chaobai River Basin controlled by the Miyun Reservoir. The model simulation suggested that not only the impact of land cover change on evapotranspiration, but also the extra water loss caused by human activities, such as the water and soil conservation development projects should be considered. Although these development projects were of great benefit to human and ecological protection, they could reallocate water resources in time and space, and in a sense thereby influence the stream flow.