Achalasia is a primary motor disorder of the eso-phagus, in which esophageal emptying is impaired. Diagnosis of achalasia is based on clinical fi ndings. The diagnosis is confirmed by radiographic, endoscopic, and man...Achalasia is a primary motor disorder of the eso-phagus, in which esophageal emptying is impaired. Diagnosis of achalasia is based on clinical fi ndings. The diagnosis is confirmed by radiographic, endoscopic, and manometric evaluations. Several treatments for achalasia have been introduced. We searched the PubMed Database for original articles and meta-analyses about achalasia to summarize the current knowledge regarding this disease, with particular focus on different procedures that are used for treatment of achalasia. We also report the Iranian experience of treatment of this disease, since it could be considered as a model for medium-resource countries. Myotomy, particularly laparoscopic myotomy with fundoplication, is the most effective treatment for achalasia. Compared to other treatments, however, the initial cost of myotomy is usually higher and the recovery period is longer. When performing myotomy is not indicated or not possible, graded pneumatic dilation with slow rate of balloon inflation seems to be an effective and safe initial alternative. Injection of botulinum toxin into the lower esophageal sphincter before pneumatic dilation may increase remission rates. However, this needs to be conf irmed in further studies. Due to lack of adequate information regarding the role of expandable stents in the treatment of achalasia, insertion of stents does not currently seem to be a recommended treatment. In summary, laparoscopic myotomy can be considered as the procedure of choice for treatment of achalasia. Graded pneumatic dilation is an effective alternative when the performance of myotomy is not possible for any reason.展开更多
Multivariate statistical technique was used to determine the potassium （K＋） status and to assess soil fertility and K leaching potential in some calcareous soils. Water-soluble K＋ （H20-K） and ammonium acetate-ex...Multivariate statistical technique was used to determine the potassium （K＋） status and to assess soil fertility and K leaching potential in some calcareous soils. Water-soluble K＋ （H20-K） and ammonium acetate-extractable K＋ （NHaOAc- K） ranged from 0.019 to 0.590 （mean value 0.095） and 0.390 to 3.320 （mean value 0.954） cmolc kg-1, respectively. The nitric acid-extractable K＋ （HNO3-K） varied from 1.03 to 13.63 （mean value 5.37） cmolc kg-1. The proportion of H20-K ranged from 0.34% to 14.8% of HNO3-K, and 2.2% to 53.2% of NHaOAc-K. The proportion of NHaOAc-K ranged from 5.8% to 80% of HNO3-K （mean value 23% of HNOa-K）. The tendency of the soil to lose K＋ by leaching was examined by determining K＋-Ca2＋ exchange isotherms. The soils mostly had moderate to high values of K＋ sorption capacity, ranging from 10% to 58% （mean value 28%） of added K＋. The Gapon coefficient varied widely from 1.1 to 12.0 （L mol-1）-1/2. Clay minerals were dominated by illite, smectites and vermiculite with small amounts of kaolinite. Principal component analysis （PCA） showed that the first four components accounted for 27.7%, 21.4%, 13.8%, and 8.9% of total variation, respectively. The non-hierarchical cluster analysis （k-means clustering） grouped 75 sampling sites into six clusters, based on the similarity of soil quality characteristics. The results suggested that such classes could form a basis for variable-rate application to maintain an adequate K＋ status for crop production and to reduce potential K＋ loss from soil by leaching.展开更多
A list of Heteroptera collected from Arasbaran Biosphere Reserve(East Azarbayjan Province,northwestern Iran) and neighboring areas is provided. A total of 114 species from 87 genera and 19 families were collected from...A list of Heteroptera collected from Arasbaran Biosphere Reserve(East Azarbayjan Province,northwestern Iran) and neighboring areas is provided. A total of 114 species from 87 genera and 19 families were collected from Arasbaran and vicinity. Two species are new records for Iran: Gerris(Gerris) maculatus Tamanini and Sigara(Vermicorixa) lateralis(Leach).展开更多
Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more t...Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more than 5 meters reflecting that the aquifer is under stress condition. As a result, interest is focused on application of artificial recharge as an option for groundwater management to augment water supply in this area. Therefore, in the present investigations, suitable sites for artificial recharge were selected by an integrated surface and sub-surface assessment of the area. On the basis of the data collected from four target points, it was realized that the selected sites for artificial recharge could not meet water demand of the area. In this study attention was also paid to utilization of the existing Miangran Lake water as an alternative to combat water shortage for irrigation. The study further indicated that the available Miangran Lake water could be used for irrigation of the reclaimed agricultural land and enabling to convert 20o0 hectares of rain-fed land into irrigation. The total cost to utilize lake water is US$ 2,756,729 and it was estimated that the project could recoup the investment within 5 years which is quite reasonable in this water scarcity prone area.展开更多
Soil depth generally varies in mountainous regions in rather complex ways.Conventional soil survey methods for evaluating the soil depth in mountainous and hilly regions require a lot of time,effort and consequently r...Soil depth generally varies in mountainous regions in rather complex ways.Conventional soil survey methods for evaluating the soil depth in mountainous and hilly regions require a lot of time,effort and consequently relatively large budget to perform.This study was conducted to explore the relationships between soil depth and topographic attributes in a hilly region in western Iran.For this,one hundred sampling points were selected using randomly stratified methodology,and considering all geomorphic surfaces including summit,shoulder,backslope,footslope and toeslope;and soil depth was actually measured.Eleven primary and secondary topographic attributes were derived from the digital elevation model(DEM) at the study area.The result of multiple linear regression indicated that slope,wetness index,catchment area and sediment transport index,which were included in the model,could explain about 76 % of total variability in soil depth at the selected site.This proposed approach may be applicable to other hilly regions in the semi-arid areas at a larger scale.展开更多
Atterberg limits and consistency indices are used for classifications of cohesive(fine-grained) soils in relation with compaction and tillage practices. They also provide information for interpreting several soil mech...Atterberg limits and consistency indices are used for classifications of cohesive(fine-grained) soils in relation with compaction and tillage practices. They also provide information for interpreting several soil mechanical and physical properties such as shear strength, compressibility, shrinkage and swelling potentials. Although, several studies have been conducted regarding the land use effects on various soil mechanical properties, little is known about the effects of land use and slope positions on Atterberg limits and consistency indices. This study was conducted to investigate the effects of land use and slope position on selected soil physical and chemical properties, Atterberg limits and consistency indices in hilly region of western Iran. Three land uses including dryland farming, irrigated farming and pasture and four slope positions(i.e., shoulder, backslope, footslope, and toeslope) were used for soil samplings. One hundred eleven soil samples were collected from the surface soil(0-10 cm). Selected physical and chemical properties, liquid limit(LL), plastic limit(PL) and shrinkage limit(SL) were measured using the standard methods; and consistency indices including plastic index(PI), friability index(FI), shrinkage index(SI) and soil activity(A=PI/clay) were calculated. The results showed that irrigated farming significantly increased organic matter content(OM) and OM/clay ratio, and decreased bulk density(ρb) and relative bulk density(ρb-rel) as a result of higher biomass production and plant residues added to the soil compared to other land uses. Except for sand content, OM, ρb, cation exchange capacity(CEC) and calcium carbonate equivalent(CCE), slope position significantly affected soil physical and chemical properties. The highest values of silt, OM/clay and CEC/clay were found in the toeslope position, predominantly induced by soil redistribution within the landscape. The use of complexed(COC)- noncomplexed organic carbon(NCOC) concept indicated that majority of the studied soils were located below the saturation line and the OM in the soils was mainly in the COC form. The LL, PI, FI and A showed significant differences among the land uses; the highest values belonged to the irrigated farming due to high biomass production and plant residues returned to the soils. Furthermore, slope position significantly affected the Atterberg limits and consistency indices except for SL. The highest values of LL, PI, SI and A were observed in the toeslope position probably because of higher OM and CEC/clay due to greater amount of expandable phyllosilicate clays. Overall, soils on the toeslope under irrigated farming with high LL and SI and low values of FI need careful tillage management to avoid soil compaction.展开更多
In 2013,a novel disease was detected in tilapia( Oreochromis niloticus × O.aureus) in Guangzhou,South China.To identify the causative pathogen,we conducted histological examination,bacteria isolation,and purifica...In 2013,a novel disease was detected in tilapia( Oreochromis niloticus × O.aureus) in Guangzhou,South China.To identify the causative pathogen,we conducted histological examination,bacteria isolation,and purification,and sequenced the 16 S rRNA gene of isolates.Infected fish had a large number of white granulomas in the kidney,liver,heart,and spleen.The head kidney and spleen were markedly swollen.A bacterium strain designated as gz201301 was recovered from the spleen of infected tilapia.The 16 S rRNA sequence of gz201301 revealed that it was highly similar to F.noatunensis subsp.orientalis.This is the first report of a Francisella-like infection in farmed tilapia in China.展开更多
文摘Achalasia is a primary motor disorder of the eso-phagus, in which esophageal emptying is impaired. Diagnosis of achalasia is based on clinical fi ndings. The diagnosis is confirmed by radiographic, endoscopic, and manometric evaluations. Several treatments for achalasia have been introduced. We searched the PubMed Database for original articles and meta-analyses about achalasia to summarize the current knowledge regarding this disease, with particular focus on different procedures that are used for treatment of achalasia. We also report the Iranian experience of treatment of this disease, since it could be considered as a model for medium-resource countries. Myotomy, particularly laparoscopic myotomy with fundoplication, is the most effective treatment for achalasia. Compared to other treatments, however, the initial cost of myotomy is usually higher and the recovery period is longer. When performing myotomy is not indicated or not possible, graded pneumatic dilation with slow rate of balloon inflation seems to be an effective and safe initial alternative. Injection of botulinum toxin into the lower esophageal sphincter before pneumatic dilation may increase remission rates. However, this needs to be conf irmed in further studies. Due to lack of adequate information regarding the role of expandable stents in the treatment of achalasia, insertion of stents does not currently seem to be a recommended treatment. In summary, laparoscopic myotomy can be considered as the procedure of choice for treatment of achalasia. Graded pneumatic dilation is an effective alternative when the performance of myotomy is not possible for any reason.
文摘Multivariate statistical technique was used to determine the potassium （K＋） status and to assess soil fertility and K leaching potential in some calcareous soils. Water-soluble K＋ （H20-K） and ammonium acetate-extractable K＋ （NHaOAc- K） ranged from 0.019 to 0.590 （mean value 0.095） and 0.390 to 3.320 （mean value 0.954） cmolc kg-1, respectively. The nitric acid-extractable K＋ （HNO3-K） varied from 1.03 to 13.63 （mean value 5.37） cmolc kg-1. The proportion of H20-K ranged from 0.34% to 14.8% of HNO3-K, and 2.2% to 53.2% of NHaOAc-K. The proportion of NHaOAc-K ranged from 5.8% to 80% of HNO3-K （mean value 23% of HNOa-K）. The tendency of the soil to lose K＋ by leaching was examined by determining K＋-Ca2＋ exchange isotherms. The soils mostly had moderate to high values of K＋ sorption capacity, ranging from 10% to 58% （mean value 28%） of added K＋. The Gapon coefficient varied widely from 1.1 to 12.0 （L mol-1）-1/2. Clay minerals were dominated by illite, smectites and vermiculite with small amounts of kaolinite. Principal component analysis （PCA） showed that the first four components accounted for 27.7%, 21.4%, 13.8%, and 8.9% of total variation, respectively. The non-hierarchical cluster analysis （k-means clustering） grouped 75 sampling sites into six clusters, based on the similarity of soil quality characteristics. The results suggested that such classes could form a basis for variable-rate application to maintain an adequate K＋ status for crop production and to reduce potential K＋ loss from soil by leaching.
基金supported by grants from Shahre Rey Islamic Azad University,the National Natural Science Foundation of China(30825006,30970394)the Doctoral Program of Higher Education of China(200800190015)
文摘A list of Heteroptera collected from Arasbaran Biosphere Reserve(East Azarbayjan Province,northwestern Iran) and neighboring areas is provided. A total of 114 species from 87 genera and 19 families were collected from Arasbaran and vicinity. Two species are new records for Iran: Gerris(Gerris) maculatus Tamanini and Sigara(Vermicorixa) lateralis(Leach).
文摘Ever growing demand for water for agricultural activities in the Izeh Plain has enhanced the use of groundwater. Due to enormous groundwater abstraction since 1985, the overall static water level has receded by more than 5 meters reflecting that the aquifer is under stress condition. As a result, interest is focused on application of artificial recharge as an option for groundwater management to augment water supply in this area. Therefore, in the present investigations, suitable sites for artificial recharge were selected by an integrated surface and sub-surface assessment of the area. On the basis of the data collected from four target points, it was realized that the selected sites for artificial recharge could not meet water demand of the area. In this study attention was also paid to utilization of the existing Miangran Lake water as an alternative to combat water shortage for irrigation. The study further indicated that the available Miangran Lake water could be used for irrigation of the reclaimed agricultural land and enabling to convert 20o0 hectares of rain-fed land into irrigation. The total cost to utilize lake water is US$ 2,756,729 and it was estimated that the project could recoup the investment within 5 years which is quite reasonable in this water scarcity prone area.
文摘Soil depth generally varies in mountainous regions in rather complex ways.Conventional soil survey methods for evaluating the soil depth in mountainous and hilly regions require a lot of time,effort and consequently relatively large budget to perform.This study was conducted to explore the relationships between soil depth and topographic attributes in a hilly region in western Iran.For this,one hundred sampling points were selected using randomly stratified methodology,and considering all geomorphic surfaces including summit,shoulder,backslope,footslope and toeslope;and soil depth was actually measured.Eleven primary and secondary topographic attributes were derived from the digital elevation model(DEM) at the study area.The result of multiple linear regression indicated that slope,wetness index,catchment area and sediment transport index,which were included in the model,could explain about 76 % of total variability in soil depth at the selected site.This proposed approach may be applicable to other hilly regions in the semi-arid areas at a larger scale.
基金Isfahan University of Technology for the financial support of this study
文摘Atterberg limits and consistency indices are used for classifications of cohesive(fine-grained) soils in relation with compaction and tillage practices. They also provide information for interpreting several soil mechanical and physical properties such as shear strength, compressibility, shrinkage and swelling potentials. Although, several studies have been conducted regarding the land use effects on various soil mechanical properties, little is known about the effects of land use and slope positions on Atterberg limits and consistency indices. This study was conducted to investigate the effects of land use and slope position on selected soil physical and chemical properties, Atterberg limits and consistency indices in hilly region of western Iran. Three land uses including dryland farming, irrigated farming and pasture and four slope positions(i.e., shoulder, backslope, footslope, and toeslope) were used for soil samplings. One hundred eleven soil samples were collected from the surface soil(0-10 cm). Selected physical and chemical properties, liquid limit(LL), plastic limit(PL) and shrinkage limit(SL) were measured using the standard methods; and consistency indices including plastic index(PI), friability index(FI), shrinkage index(SI) and soil activity(A=PI/clay) were calculated. The results showed that irrigated farming significantly increased organic matter content(OM) and OM/clay ratio, and decreased bulk density(ρb) and relative bulk density(ρb-rel) as a result of higher biomass production and plant residues added to the soil compared to other land uses. Except for sand content, OM, ρb, cation exchange capacity(CEC) and calcium carbonate equivalent(CCE), slope position significantly affected soil physical and chemical properties. The highest values of silt, OM/clay and CEC/clay were found in the toeslope position, predominantly induced by soil redistribution within the landscape. The use of complexed(COC)- noncomplexed organic carbon(NCOC) concept indicated that majority of the studied soils were located below the saturation line and the OM in the soils was mainly in the COC form. The LL, PI, FI and A showed significant differences among the land uses; the highest values belonged to the irrigated farming due to high biomass production and plant residues returned to the soils. Furthermore, slope position significantly affected the Atterberg limits and consistency indices except for SL. The highest values of LL, PI, SI and A were observed in the toeslope position probably because of higher OM and CEC/clay due to greater amount of expandable phyllosilicate clays. Overall, soils on the toeslope under irrigated farming with high LL and SI and low values of FI need careful tillage management to avoid soil compaction.
基金Supported by the Pearl River Science&Technology Nova Program of Guangzhou City(No.2012J2200078)the Marine Fishery Science&Technology Promotion Project of Guangdong Provinces(No.A201301B06)
文摘In 2013,a novel disease was detected in tilapia( Oreochromis niloticus × O.aureus) in Guangzhou,South China.To identify the causative pathogen,we conducted histological examination,bacteria isolation,and purification,and sequenced the 16 S rRNA gene of isolates.Infected fish had a large number of white granulomas in the kidney,liver,heart,and spleen.The head kidney and spleen were markedly swollen.A bacterium strain designated as gz201301 was recovered from the spleen of infected tilapia.The 16 S rRNA sequence of gz201301 revealed that it was highly similar to F.noatunensis subsp.orientalis.This is the first report of a Francisella-like infection in farmed tilapia in China.
