In the experiment, by taking Quercus engleriana Seem., Betula albo- sinensis Burk., Abies faxoniana Rehd. and Fargesia rufa Yi, in the vegetation restoration pattern area of Beichuan Nature Reserve as the research obj...In the experiment, by taking Quercus engleriana Seem., Betula albo- sinensis Burk., Abies faxoniana Rehd. and Fargesia rufa Yi, in the vegetation restoration pattern area of Beichuan Nature Reserve as the research objects, the study on the biomass models, the biomass distribution law of single plant and the growth rule of every organ of the four tree species was made. The results indicated that in the compositions of all of the species, the proportion of trunk biomass was the highest, while that of trunk biomass was the lowest, the proportions of branch and root biomasses varied depending on species; in the comparison of correlativity between the proportions of biomasses of all nutrition organs and biomass of single plant, the relations were generally significant, the tree trunks were positively related while the roots were negatively related; the proportion of trunk biomass of all species was significantly and negatively related to the proportions of leaf and branch biomasses, while the biomass of leaves was significantly and positively related to the biomass of branches.展开更多
In the high mountain oligotrophic Seven Rila Lakes (2 095–2 535 m a.s.l.) bacterial abundance was recorded in July and September 2006. In July, bacterial abundance (average (3.32±2.5)×105 cell/ml) in the la...In the high mountain oligotrophic Seven Rila Lakes (2 095–2 535 m a.s.l.) bacterial abundance was recorded in July and September 2006. In July, bacterial abundance (average (3.32±2.5)×105 cell/ml) in the lakes correlated negatively with elevation, while in September (average (26.39±7.1)×105 cell/ml) this pattern was altered and the greatest abundance of bacteria occurred at the highest ((39.05±1.5)×105 cell/ml) and the lowest ((30.63±6.0)×105 cell/ml) elevated lakes. Regression analyses suggested that the principal factor controlling bacterial abundance, in both July and September, was inorganic nitrogen (NO3-N and NH4-N; R2=0.70, P<0.05). Other major regulating factors were temperature (R2=0.66, P<0.03) in July and filter-feeding zooplankton (R2=0.95, P<0.01) in September. All factors, except NO3-N, had a positive effect on bacterial abundance.展开更多
AIM:To investigate the prevalence and risk factors of asymptomatic peptic ulcer disease(PUD)in a general Taiwan Residents population. METHODS:From January to August 2008,consecutive asymptomatic subjects undergoing a ...AIM:To investigate the prevalence and risk factors of asymptomatic peptic ulcer disease(PUD)in a general Taiwan Residents population. METHODS:From January to August 2008,consecutive asymptomatic subjects undergoing a routine health check-up were evaluated by upper gastrointestinal endoscopy.Gastroduodenal mucosal breaks were carefully assessed,and a complete medical history and demographic data were obtained from each patient.Logistic regression analysis was conducted to identify indepen-dent risk factors for asymptomatic PUD. RESULTS:Of the 572 asymptomatic subjects,54(9.4%) were diagnosed as having PUD.The prevalence of gastric ulcer,duodenal ulcer and both gastric and duodenal ulcers were 4.7%,3.9%,and 0.9%,respectively. Multivariate analysis revealed that prior history of PUD [odds ratio(OR),2.0,95%CI:1.3-2.9],high body mass index[body mass index(BMI)25-30:OR,1.5,95%CI: 1.0-2.2;BMI>30 kg/m 2 :OR,3.6,95%CI:1.5-8.7] and current smoker(OR,2.6,95%CI:1.6-4.4)were independent predictors of asymptomatic PUD.In contrast, high education level was a negative predictor of PUD (years of education 10-12:OR,0.5,95%CI:0.3-0.8; years of education>12:OR,0.6,95%CI:0.3-0.9). CONCLUSION:The prevalence of PUD in asymptomatic subjects is 9.4%in Taiwan.Prior history of PUD, low education level,a high BMI and current smoker are independent risk factors for developing asymptomatic PUD.展开更多
Objective Brachial-ankle pulse wave velocity （baPWV） is widely used as a simple noninvasive measure of arterial softness. The aim of this study was to evaluate the usefulness of baPWV as a predictor of the carotid a...Objective Brachial-ankle pulse wave velocity （baPWV） is widely used as a simple noninvasive measure of arterial softness. The aim of this study was to evaluate the usefulness of baPWV as a predictor of the carotid artery atherosclerosis in the elderly. Methods A total of 721 elderly participants （mean ~ SD age, 70.3 -4- 5.6years） were enrolled in the current study. All participant underwent both baPWV measurement and B-mode ultrasound for the intima-media thickness. Carotid atherosclerosis （CAS） was defined as the present of carotid plaque or and/or intima media thickness for at least 1.1 mm. Results A multivariate logistic regression analysis reveals that age, sex, brachial-ankle pulse wave velocity, smoking and LDL-C level showed a significant correlation with the presence of CAS. The odds ratios of CAS associated with a 500cm/s increase of brachial-ankle pulse wave velocity were 2.378 [95% confidence interval, 1.36 to 4.00, P〈0.05], 3.733 [95% confidence interval, 1.729 to 8.058, P〈0.01], 4.438 [95% confidence interval, 1.659 to 11.803, P〈0.01]. The baPWV significantly correlated with IMT by bivariate correlation analysis （r=-0.39; p=0.001）. After adjusting for factors influencing, baPWV all the same correlated with IMT （r=-0.35; p=0.001）.Conclusion These results indicate that brachial-ankle PWV is an independent predictor of CAS in the elderly.It also means that the direct measurement of arterial stiffness by this simple method may be of great help for the evaluation of carotid artherosclerosis, at least in the elderly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
Corn steep liquor(CSL) is an important raw material that has high nutritional value and serves as a nitrogen source.Biotin in CSL is especially of great importance to fermentation.In order to develop a fast,versatile,...Corn steep liquor(CSL) is an important raw material that has high nutritional value and serves as a nitrogen source.Biotin in CSL is especially of great importance to fermentation.In order to develop a fast,versatile,cheap,and environmentally safe analytical method for quantifying vitamins B2(VB2),B3(VB3),B6(VB6) and B7(VB7) in CSL,the near-infrared spectroscopy(NIR) measurements of 66 samples(22 batches) of CSL were analyzed by partial least-square regression(PLSR).Multivariate models developed in the NIR regions showed good predictive abilities for VB2,VB3,VB6 and VB7.Results confirmed the probability of the multivariate spectroscopic approach as a replacement for expensive and time-consuming conventional chemical methods.展开更多
The purpose of this study is to identify the determinants of adoption of sawah technology in Ashanti region of Ghana. It identifies those independent variables that explain adoption and can also facilitate further dis...The purpose of this study is to identify the determinants of adoption of sawah technology in Ashanti region of Ghana. It identifies those independent variables that explain adoption and can also facilitate further dissemination and adoption of sawah technology. Sawah refers to leveled rice field surrounded by banks with inlet and outlet for irrigation and drainage. This study uses data from 108 farmers randomly selected from 198 sawah farmers in the study area. Regression analysis showed that age, educational level and year of experience in rice production were the personal factors that determined the adoption of sawah technology among the respondents. The result further showed that contact with extension agents, attendance in previous sawah trainings, land tenure arrangement, yield from sawah farm and attributes of sawah technology determined adoption. This study suggested that adoption of sawah technology should be targeted at young, educated and experienced farmers. Also, security of land must be ascertained by farmers in order to enhance adoption, continuous and sustained use of sawah technology.展开更多
AIM:To examine the association between parity and gastric cancer (the cases are almost all premenopausal women) risk in a cohort of young parous women.METHODS:The study cohort consisted of all women with a record of a...AIM:To examine the association between parity and gastric cancer (the cases are almost all premenopausal women) risk in a cohort of young parous women.METHODS:The study cohort consisted of all women with a record of a first and singleton childbirth in the Birth Register between 1978 and 1987.We tracked each woman from the time of her first childbirth to December 31,2008.Their vital status was ascertained by linking records to the computerized mortality database.Cox proportional hazard regression models were used to estimate hazard ratios of death from gastric cancer associated with parity.RESULTS:There were 1090 gastric cancer deaths (85.87% of them were premenopausal) during 33686828 person-years of follow-up.The mortality rate of gastric cancer was 3.24 cases per 100000 person-years.A trend of increasing risk of gastric cancer was seen with increasing parity.The adjusted hazard ratio was 1.24 [confidence interval (95% CI):1.02-1.50] for women who had borne two to three children,and 1.32 (95% CI:1.01-1.72) for women with four or more births,when compared with women who had given birth to only one child.CONCLUSION:These results suggest that higher parity may increase the risk of death from gastric cancer among premenopausal women.展开更多
On the basis of panel data from 29 provinces and cities throughout the country in 2006-2010, a research is made on factors influencing regional industrial solid waste comprehensive utilization ability through a regres...On the basis of panel data from 29 provinces and cities throughout the country in 2006-2010, a research is made on factors influencing regional industrial solid waste comprehensive utilization ability through a regression analysis method. Research result shows that a positive influence will generate on the comprehensive utilization ability of the industrial solid waste by three factors： regional industrial soldi waste treatment earning level, regional industrial soldi waste treatment investment level and regional industrial pollution treatment subsidy strength. And this thesis will propose suggestions from improving earning ability, enhartcing treatment investment and increasing government subsidy depending on result of empirical analysis.展开更多
In this study, the relationship between the QBO （quasi-biennial oscillation）, which is seen at the equatorial stratosphere, and critical frequency of layer （Es） sporadically observed at the ionospheric E region wa...In this study, the relationship between the QBO （quasi-biennial oscillation）, which is seen at the equatorial stratosphere, and critical frequency of layer （Es） sporadically observed at the ionospheric E region was analyzed by using multiple regression model. For this analysis, Es layer critical frequency （foEs） obtained from four different stations at equatorial region and QBO measured at 10 hPa altitude values were used. The positive relationship between foEs and QBO was observed at all stations. An increase of 1 m/s at QBO leads to an increase of 0.01 Mhz, 0.02 Mhz, 0.02 Mhz and 0.01 Mhz （Jicamarca, Ascension, Manila and Kwajalein） on foEs, respectively. Expect for Manila station, westerly phase of QBO has greater effect on foEs compared to easterly phase of QBO at all other stations. It is seen that the changes occurred on foEs can be explained by the QBO at rates 47%, 46%, 32% and 44% for Jicamarca, Ascension, Manila and Kwajalein stations, respectively.展开更多
基金Supported by the Restoring&Reconstruction Project of Giant Panda Habitat after the Wenchuan Earthquake in Beichuan Qiang Minority Autonomous County~~
文摘In the experiment, by taking Quercus engleriana Seem., Betula albo- sinensis Burk., Abies faxoniana Rehd. and Fargesia rufa Yi, in the vegetation restoration pattern area of Beichuan Nature Reserve as the research objects, the study on the biomass models, the biomass distribution law of single plant and the growth rule of every organ of the four tree species was made. The results indicated that in the compositions of all of the species, the proportion of trunk biomass was the highest, while that of trunk biomass was the lowest, the proportions of branch and root biomasses varied depending on species; in the comparison of correlativity between the proportions of biomasses of all nutrition organs and biomass of single plant, the relations were generally significant, the tree trunks were positively related while the roots were negatively related; the proportion of trunk biomass of all species was significantly and negatively related to the proportions of leaf and branch biomasses, while the biomass of leaves was significantly and positively related to the biomass of branches.
基金Supported by the Sofia University "St. Kl. Ohridski" fund for scientific research (No. 90/2006)
文摘In the high mountain oligotrophic Seven Rila Lakes (2 095–2 535 m a.s.l.) bacterial abundance was recorded in July and September 2006. In July, bacterial abundance (average (3.32±2.5)×105 cell/ml) in the lakes correlated negatively with elevation, while in September (average (26.39±7.1)×105 cell/ml) this pattern was altered and the greatest abundance of bacteria occurred at the highest ((39.05±1.5)×105 cell/ml) and the lowest ((30.63±6.0)×105 cell/ml) elevated lakes. Regression analyses suggested that the principal factor controlling bacterial abundance, in both July and September, was inorganic nitrogen (NO3-N and NH4-N; R2=0.70, P<0.05). Other major regulating factors were temperature (R2=0.66, P<0.03) in July and filter-feeding zooplankton (R2=0.95, P<0.01) in September. All factors, except NO3-N, had a positive effect on bacterial abundance.
文摘AIM:To investigate the prevalence and risk factors of asymptomatic peptic ulcer disease(PUD)in a general Taiwan Residents population. METHODS:From January to August 2008,consecutive asymptomatic subjects undergoing a routine health check-up were evaluated by upper gastrointestinal endoscopy.Gastroduodenal mucosal breaks were carefully assessed,and a complete medical history and demographic data were obtained from each patient.Logistic regression analysis was conducted to identify indepen-dent risk factors for asymptomatic PUD. RESULTS:Of the 572 asymptomatic subjects,54(9.4%) were diagnosed as having PUD.The prevalence of gastric ulcer,duodenal ulcer and both gastric and duodenal ulcers were 4.7%,3.9%,and 0.9%,respectively. Multivariate analysis revealed that prior history of PUD [odds ratio(OR),2.0,95%CI:1.3-2.9],high body mass index[body mass index(BMI)25-30:OR,1.5,95%CI: 1.0-2.2;BMI>30 kg/m 2 :OR,3.6,95%CI:1.5-8.7] and current smoker(OR,2.6,95%CI:1.6-4.4)were independent predictors of asymptomatic PUD.In contrast, high education level was a negative predictor of PUD (years of education 10-12:OR,0.5,95%CI:0.3-0.8; years of education>12:OR,0.6,95%CI:0.3-0.9). CONCLUSION:The prevalence of PUD in asymptomatic subjects is 9.4%in Taiwan.Prior history of PUD, low education level,a high BMI and current smoker are independent risk factors for developing asymptomatic PUD.
文摘Objective Brachial-ankle pulse wave velocity （baPWV） is widely used as a simple noninvasive measure of arterial softness. The aim of this study was to evaluate the usefulness of baPWV as a predictor of the carotid artery atherosclerosis in the elderly. Methods A total of 721 elderly participants （mean ~ SD age, 70.3 -4- 5.6years） were enrolled in the current study. All participant underwent both baPWV measurement and B-mode ultrasound for the intima-media thickness. Carotid atherosclerosis （CAS） was defined as the present of carotid plaque or and/or intima media thickness for at least 1.1 mm. Results A multivariate logistic regression analysis reveals that age, sex, brachial-ankle pulse wave velocity, smoking and LDL-C level showed a significant correlation with the presence of CAS. The odds ratios of CAS associated with a 500cm/s increase of brachial-ankle pulse wave velocity were 2.378 [95% confidence interval, 1.36 to 4.00, P〈0.05], 3.733 [95% confidence interval, 1.729 to 8.058, P〈0.01], 4.438 [95% confidence interval, 1.659 to 11.803, P〈0.01]. The baPWV significantly correlated with IMT by bivariate correlation analysis （r=-0.39; p=0.001）. After adjusting for factors influencing, baPWV all the same correlated with IMT （r=-0.35; p=0.001）.Conclusion These results indicate that brachial-ankle PWV is an independent predictor of CAS in the elderly.It also means that the direct measurement of arterial stiffness by this simple method may be of great help for the evaluation of carotid artherosclerosis, at least in the elderly
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Supported by Foundation of Tianjin City Science and Technology Project (No.09ZCKFSH00900)
文摘Corn steep liquor(CSL) is an important raw material that has high nutritional value and serves as a nitrogen source.Biotin in CSL is especially of great importance to fermentation.In order to develop a fast,versatile,cheap,and environmentally safe analytical method for quantifying vitamins B2(VB2),B3(VB3),B6(VB6) and B7(VB7) in CSL,the near-infrared spectroscopy(NIR) measurements of 66 samples(22 batches) of CSL were analyzed by partial least-square regression(PLSR).Multivariate models developed in the NIR regions showed good predictive abilities for VB2,VB3,VB6 and VB7.Results confirmed the probability of the multivariate spectroscopic approach as a replacement for expensive and time-consuming conventional chemical methods.
文摘The purpose of this study is to identify the determinants of adoption of sawah technology in Ashanti region of Ghana. It identifies those independent variables that explain adoption and can also facilitate further dissemination and adoption of sawah technology. Sawah refers to leveled rice field surrounded by banks with inlet and outlet for irrigation and drainage. This study uses data from 108 farmers randomly selected from 198 sawah farmers in the study area. Regression analysis showed that age, educational level and year of experience in rice production were the personal factors that determined the adoption of sawah technology among the respondents. The result further showed that contact with extension agents, attendance in previous sawah trainings, land tenure arrangement, yield from sawah farm and attributes of sawah technology determined adoption. This study suggested that adoption of sawah technology should be targeted at young, educated and experienced farmers. Also, security of land must be ascertained by farmers in order to enhance adoption, continuous and sustained use of sawah technology.
基金Supported by A grant from the National Science Council,Executive Yuan,Taiwan,No.NSC-94-2314-B-037-056
文摘AIM:To examine the association between parity and gastric cancer (the cases are almost all premenopausal women) risk in a cohort of young parous women.METHODS:The study cohort consisted of all women with a record of a first and singleton childbirth in the Birth Register between 1978 and 1987.We tracked each woman from the time of her first childbirth to December 31,2008.Their vital status was ascertained by linking records to the computerized mortality database.Cox proportional hazard regression models were used to estimate hazard ratios of death from gastric cancer associated with parity.RESULTS:There were 1090 gastric cancer deaths (85.87% of them were premenopausal) during 33686828 person-years of follow-up.The mortality rate of gastric cancer was 3.24 cases per 100000 person-years.A trend of increasing risk of gastric cancer was seen with increasing parity.The adjusted hazard ratio was 1.24 [confidence interval (95% CI):1.02-1.50] for women who had borne two to three children,and 1.32 (95% CI:1.01-1.72) for women with four or more births,when compared with women who had given birth to only one child.CONCLUSION:These results suggest that higher parity may increase the risk of death from gastric cancer among premenopausal women.
文摘On the basis of panel data from 29 provinces and cities throughout the country in 2006-2010, a research is made on factors influencing regional industrial solid waste comprehensive utilization ability through a regression analysis method. Research result shows that a positive influence will generate on the comprehensive utilization ability of the industrial solid waste by three factors： regional industrial soldi waste treatment earning level, regional industrial soldi waste treatment investment level and regional industrial pollution treatment subsidy strength. And this thesis will propose suggestions from improving earning ability, enhartcing treatment investment and increasing government subsidy depending on result of empirical analysis.
文摘In this study, the relationship between the QBO （quasi-biennial oscillation）, which is seen at the equatorial stratosphere, and critical frequency of layer （Es） sporadically observed at the ionospheric E region was analyzed by using multiple regression model. For this analysis, Es layer critical frequency （foEs） obtained from four different stations at equatorial region and QBO measured at 10 hPa altitude values were used. The positive relationship between foEs and QBO was observed at all stations. An increase of 1 m/s at QBO leads to an increase of 0.01 Mhz, 0.02 Mhz, 0.02 Mhz and 0.01 Mhz （Jicamarca, Ascension, Manila and Kwajalein） on foEs, respectively. Expect for Manila station, westerly phase of QBO has greater effect on foEs compared to easterly phase of QBO at all other stations. It is seen that the changes occurred on foEs can be explained by the QBO at rates 47%, 46%, 32% and 44% for Jicamarca, Ascension, Manila and Kwajalein stations, respectively.
