OBJECTIVE: To compare the effects of a Chinese herbal suppository(Jianpi suppository) and Western Medicine(mesalazine) on hemorheology and CD62p in patients with ulcerative colitis(UC).METHODS: In a randomized trial, ...OBJECTIVE: To compare the effects of a Chinese herbal suppository(Jianpi suppository) and Western Medicine(mesalazine) on hemorheology and CD62p in patients with ulcerative colitis(UC).METHODS: In a randomized trial, 120 mild to moderate UC patients were randomly divided into two equal groups. The Jianpi suppository group used Chinese herbal suppository rectally, while the mesalazine group was treated with mesalazine tablets orally. Two 15-day courses of treatment were carried out in both groups. Changes in the hemorheology and CD62p indices in patients were observed.RESULTS: The hemorheology and CD62p indices in the Jianpi suppository group decreased significantly more than those of the mesalazine group.CONCLUSION: Jianpi suppository is effective in improving the hypercoagulability of UC patients, and therefore may be worth using in clinical practice.展开更多
Due to frequent soil Cd contamination and wide use of butachlor in China,there is a need to assess their combined toxicity to soil microorganisms.The combined effects of cadmium(Cd,10 mg kg-1 soil) and herbicide butac...Due to frequent soil Cd contamination and wide use of butachlor in China,there is a need to assess their combined toxicity to soil microorganisms.The combined effects of cadmium(Cd,10 mg kg-1 soil) and herbicide butachlor(10,50,and 100 mg kg-1 soil) on enzyme activities and microbial community structure in a paddy soil were assessed using the traditional enzyme assays and random amplified polymorphic DNA(RAPD) analysis.The results showed that urease and phosphatase activities were significantly reduced by high butachlor concentration(100 mg kg-1 soil).When the concentrations of Cd and butachlor added were at a ratio of 1:10,urease and phosphatase activities were significantly decreased whereas enzyme activities were greatly improved at the ratio of 1:5,which indicated that the combined effects of Cd and butachlor on soil urease and phosphatase activities depended largely on their addition concentration ratios.Random amplified polymorphic DNA(RAPD) analysis showed loss of original bands and appearance of new bands when compared with the control soil.Random amplified polymorphic DNA fingerprints suggested substantial differences between the control and treated soil samples,with apparent changes in the number and size of amplified DNA fragments.The addition of high concentration butachlor and the combined impacts of Cd and butachlor significantly affected the diversity of the microbial community.RAPD analysis in conjunction with other biomarkers such as soil enzyme parameters would prove a powerful ecotoxicological tool.Further investigations should be carried out to understand the clear link between RAPD patterns and enzyme activity.展开更多
It has been proved that there exists a cross coupling between vertical heat turbulent transport and vertical velocity by using linear thermodynamics. This result asserts that the vertical component of heat turbulent t...It has been proved that there exists a cross coupling between vertical heat turbulent transport and vertical velocity by using linear thermodynamics. This result asserts that the vertical component of heat turbulent transport flux is composed of both the transport of the vertical potential temperature gradient and the coupling transport of the vertical velocity. In this paper, the coupling effect of vertical velocity on vertical heat turbulent transportation is validated by using observed data from the atmospheric boundary layer to determine cross coupling coefficients, and a series of significant properties of turbulent transportation are opened out. These properties indicate that the cross coupling coefficient is a logarithm function of the dimensionless vertical velocity and dimensionless height, and is not only related to the friction velocity u., but also to the coupling roughness height zwo and the coupling temperature Two of the vertical velocity. In addition, the function relations suggest that only when the vertical velocity magnitude conforms to the limitation IW/u. I # 1, and is above the level zwo, then the vertical velocity leads to the cross coupling effect on the vertical heat turbulent transport flux. The cross coupling theory and experimental results provide a challenge to the traditional turbulent K closure theory and the Monin-Obukhov similarity theory.展开更多
Developing the low carbon ecological circular agriculture is an effective approach to realizing low carbon development of agriculture. Through investigation on existing measures and performance of development of low c...Developing the low carbon ecological circular agriculture is an effective approach to realizing low carbon development of agriculture. Through investigation on existing measures and performance of development of low carbon type ecological circular agriculture in Nantong City, we analyzed the potential and problems of Nantong City in developing low carbon type ecological circular agriculture. Finally, with reference to domestic and foreign research achievements and practical experience, we put forward countermeasures for developing low carbon type ecological circular agriculture in Nantong City from building technical system and government guidance.展开更多
Magnetically modified palygorskite composites were synthesized with γ-Fe2O3 dispersing on the external surface of clay mineral. The magnetic clay was characterized with Fourier transform infrared, X-ray diffrac- tion...Magnetically modified palygorskite composites were synthesized with γ-Fe2O3 dispersing on the external surface of clay mineral. The magnetic clay was characterized with Fourier transform infrared, X-ray diffrac- tion, transmission electron microscopy, and vibrating sample magnetometer. Candida sp. 99-125 lipase was immobilized on magnetic palygorskite composites by physical adsorption with enzyme loading of 41.5 mg· g^-1 support and enzyme activity of 2631.6 U· （g support）^-1. The immobilized lipase exhibit better thermal and broader pH stability and excellent reusabilitV compared with free lipase.展开更多
In a developing country like Ghana, the study of land use and land cover change(LULCC) based on satellite imageries still remains a challenge due to cost, resolution and availability with less skilled man power. Exist...In a developing country like Ghana, the study of land use and land cover change(LULCC) based on satellite imageries still remains a challenge due to cost, resolution and availability with less skilled man power. Existing researches are skewed towards the southerly part of Ghana thereby leaving the Northern sectors uncovered. The maximum likelihood classification(MLC) algorithm was employed for the LULCC between 2000 and 2014 in Nadowli: an area characterized by an upsurge in mining in the Northern belt of Ghana. A spatial-social approach was utilized combining both satellite imagery and socio economic data. Land use transition matrix, land use integrated index/degree indices was used to depict the characters of the change. A semi structured interview, pair wise ranking and key informant interviews were used to correlate the socio economic impact of the different LULC. Overall changes in the landscape showed an increase in bare ground by 19.22%, open savannah by 16.8% whereas closed savanna decreased by 50%. Land use change matrix showed increasing trends of bare ground at the expense of vegetation. The integrated land use index highlighted the bare ground and built up areas rising with a decreasing closed vegetation woodlot. Large farm size are shrinking whiles majority of the people view mining as the main socio economic activity affecting the environment and the reduction in vegetation. This study therefore provides a strategic guide and a baseline data for land use policy actors in the Northern belt of Ghana. This will aid in developing models for future land use change implications in surrounding areas where mining is on the rise.展开更多
Naturally-occurring and artificially-induced polyploids have been documented in various fish species but to date no comparison has been reported of the impacts of ploidy on fish biomarker responses to organic pollutan...Naturally-occurring and artificially-induced polyploids have been documented in various fish species but to date no comparison has been reported of the impacts of ploidy on fish biomarker responses to organic pollutants.This study describes effects of ploidy,gender,and dose on biliary fluorescent aromatic compound（FAC） concentrations,hepatic ethoxyresorufin-O-deethylase（EROD） and glutathione S-transferase（GST） activities in one of the most commonly cultured warm-water species,the African catfish Clarias gariepinus.Recently matured male and female diploid and triploid fish were intraperitoneally（i.p.）injected with 0,5 or 25 mg/kg benzo[a]pyrene（BaP） and liver and gallbladder were sampled48 hr later.No significant differences were found between ploidies in bile concentrations of7,8 dihydrodiolbenzo[a]pyrene（7,8D BaP）,1-hydroxybenzo[a]pyrene（1-OH BaP） or3-hydroxybenzo[a]pyrene（3-OH BaP）.However,concentrations of the biliary FACs did differ between males and females at different dose of injection with generally higher concentrations in females at the low dose of BaP and higher concentrations in males at the higher BaP concentration.Hepatic EROD activity did not exhibit gender-dependent difference,whereas it was significantly higher in triploids than diploids.GST activities were not significantly influenced by any of the tested factors.This work advanced our understanding of the role of ploidy,gender,and dose in biotransformation of pollutants in fish.展开更多
Bacterial leaf blight(BLB)and bacterial leaf streak(BLS),caused by Xanthomonas oryzae pv.oryzae(Xoo)and X.oryzae pv.oryzicola(Xoc),respectively,lead to severe loss in yields and quality in most rice-growing areas arou...Bacterial leaf blight(BLB)and bacterial leaf streak(BLS),caused by Xanthomonas oryzae pv.oryzae(Xoo)and X.oryzae pv.oryzicola(Xoc),respectively,lead to severe loss in yields and quality in most rice-growing areas around the world.As the staple crop and the model plant for biology research,characterizing the diseases of rice has great significance.It is crucial to elucidate the interaction between the pathogens and rice as well as the mechanisms of pathogenesis and resistance.The special topic of the three papers is the pathogenicity of plant pathogenic bacteria and host resistance to pathogens.展开更多
Background: Modelling aboveground biomass(AGB) in forest and woodland ecosystems is critical for accurate estimation of carbon stocks. However, scarcity of allometric models for predicting AGB remains an issue that ha...Background: Modelling aboveground biomass(AGB) in forest and woodland ecosystems is critical for accurate estimation of carbon stocks. However, scarcity of allometric models for predicting AGB remains an issue that has not been adequately addressed in Africa. In particular, locally developed models for estimating AGB in the tropical woodlands of Ghana have received little attention. In the absence of locally developed allometric models, Ghana will continue to use Tier 1 biomass data through the application of pantropic models. Without local allometric models it is not certain how Ghana would achieve Tier 2 and 3 levels under the United Nations programme for reducing emissions from deforestation and forest degradation. The objective of this study is to develop a mixedspecies allometric model for use in estimating AGB for the tropical woodlands in Ghana. Destructive sampling was carried out on 745 trees(as part of charcoal production) for the development of allometric equations. Diameter at breast height(dbh, i.e. 1.3 m above ground level), total tree height(H) and wood density(ρ) were used as predictors for the models. Seven models were compared and the best model selected based on model efficiency,bias(%) and corrected Akaike Information Criterion. The best model was validated by comparing its results with those of the pantropic model developed by Chave et al.(Glob Chang Biol 20:3177–3190, 2014) using equivalence test and conventional paired t-test.Results: The results revealed that the best model for estimating AGB in the tropical woodlands is AGB =0.0580ρ((dbh)2 H)0.999. The equivalence test showed that this model and the pantropic model developed by Chave et al.(Glob Chang Biol 20:3177–3190, 2014) were equivalent within ±10% of their mean predictions(p-values <0.0001 for one-tailed t-tests for both lower and upper bounds at 5% significant level), while the paired t-test revealed that the mean(181.44 ± 18.25 kg) of the model predictions of the best model of this study was significantly(n = 745, mean diff. = 16.50 ± 2.45 kg;S.E. = 1.25 kg;p < 0.001) greater than that(164.94 ± 15.82 kg) of the pantropic model of Chave et al.(Glob Chang Biol 20:3177–3190, 2014).Conclusion: The model developed in this study fills a critical gap in estimating AGB in tropical woodlands in Ghana and other West African countries with similar ecological conditions. Despite the equivalence with the pantropic model it remains superior to the model of Chave et al.(Glob Chang Biol 20:3177–3190, 2014) for the estimation of AGB in local tropical woodlands. It is a relevant tool for the attainment of Tier 2 and 3 levels for REDD+. The model is recommended for use in the tropical woodlands in Ghana and other West African countries in place of the use of pantropic models.展开更多
OBJECTIVE: This article investigates the methods of achieving deep remission of inflammatory bowel disease (IBD). METHODS: Increasing recognition of the concept of quality of care is contributing to the evolution of t...OBJECTIVE: This article investigates the methods of achieving deep remission of inflammatory bowel disease (IBD). METHODS: Increasing recognition of the concept of quality of care is contributing to the evolution of treatment goals in patients with IBD from clinical response and remission (symptom control) toward deep remission. A change in the treatment goal requires a change in the treatment strategy. Optimization of conventional therapy, early treatment, use of the Lemann score, performance of double-balloon endoscopy, treatment using Traditional Chinese Medicine, and good communication between physicians and patients are needed to attain deep remission. RESULTS: The above-mentioned methods can help to achieve deep remission. CONCLUSION: Using the above methods, it will bepossible to improve the prognoses of patients with IBD by minimizing complications and bowel damage and thereby changing the course of the disease.展开更多
Bleeding canker (BC) of pear trees, is a devastating disease in China. The disease was originally observed in Jiangsu Province and its causal agent was identified first as Erwinia sp. in the early 1970's and latte...Bleeding canker (BC) of pear trees, is a devastating disease in China. The disease was originally observed in Jiangsu Province and its causal agent was identified first as Erwinia sp. in the early 1970's and latter as a novel species, Dickeya fangzhongdai. BC is epidemically emerging prevalently from April to September annually in pear-growing regions in Zhejiang, Anhui and Shandong provinces, and threatening pear industry currently in China. To better control BC disease, it is crucial to know BC symptomatology, epidemics, etiology, and diagnostics first. The special topic of the three papers have well illustrated the points mentioned above.展开更多
The study assesses the quality of hand dug wells in relation to distance from soakaway septic tanks in three selected peri-urban communities in the Ga West Municipality near Accra, Ghana. Water quality analyses of bio...The study assesses the quality of hand dug wells in relation to distance from soakaway septic tanks in three selected peri-urban communities in the Ga West Municipality near Accra, Ghana. Water quality analyses of bio-physico-chemical variables (pH, Temperature, EC, turbidity, DO, BOD, TSS, TDS, sodium, potassium, nitrate, nitrite, ammonia, sulphate, chloride, salinity, total alkalinity, total coliform, fecal coliforms and isolation of <i>E. coli</i>) were determined. Concentrations of the major nutrient anion sulphate, nitrate, phosphate, and chlorides in water samples at distances between 0</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">30 m radial distances from the septic tank were above the WHO permissible limit of drinking water compared to the control. All the water samples had high fecal and total coliform counts that exceeded the international standard of 0 per 100 mL of potable water with counts ranging from 0</span><span style="font-family:""> - </span><span style="font-family:"">143</span><span style="font-family:""> </span><span style="font-family:"">cfu/100</span><span style="font-family:""> </span><span style="font-family:"">ml and 53</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">463/100</span><span style="font-family:""> </span><span style="font-family:"">ml for FC and TC respectively. High fecal coliform and detection of <i>E. coli</i> in most samples is an indication of fecal pollution possibly from their close proximity to soak away septic sewage. The high nutrient levels detected in samples at distances between 0</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">30</span><span style="font-family:""> </span><span style="font-family:"">m as compared to the controls may also be attributed to its close proximity to septic tanks. This study, therefore, accentuates the need for the owners of the water points to site their water source at least 30m away </span><span style="font-family:"">from </span><span style="font-family:"">localized sources of pollution as well as treatment of groundwater before use.展开更多
Xanthomonas oryzea pv.oryzae(Xoo)is the causal agent of bacterial blight of rice,which is a significant threat to many of rice-growing regions.The type Ⅲ secretion system(T3SS)is an essential virulence factor in Xoo....Xanthomonas oryzea pv.oryzae(Xoo)is the causal agent of bacterial blight of rice,which is a significant threat to many of rice-growing regions.The type Ⅲ secretion system(T3SS)is an essential virulence factor in Xoo.Expression of the T3SS is often induced in the host environment or in hrp-inducing medium but is repressed in nutrient-rich medium.The elucidation of molecular mechanism underlying induction of T3SS genes expression is a very important step to lift the veil on global virulence regulation network in Xoo.Thus,an efficient and reliable genetic tool system is required for detection of the T3SS proteins.In this study,we constructed a protein expression vector pH3-flag based on the backbone of pHM1,a most widely used vector in Xoo strains,especially a model strain PXO99A.This vector contains a synthesized MCS-FLAG cassette that consists of a multiple cloning site(MCS),containing a modified pUC18 polylinker,and Flag as a C-terminal tag.The cassette is flanked by transcriptional terminators to eliminate interference of external transcription enabling detection of accurate protein expression.We evaluated the potential of this expression vector as T3SS proteins detection system and demonstrated it is applicable in the study of T3SS genes expression regulation in Xoo.This improved expression system could be very effectively used as a molecular tool in understanding some virulence genes expression and regulation in Xoo and other Xanthomonas spp.展开更多
This study applies a directional distance function(DDF)data envelopment analysis(DEA)model to measure the environmental efficiency of 12 U.S.airlines 2013–2016 by considering flight delay and greenhouse gas(GHG)emiss...This study applies a directional distance function(DDF)data envelopment analysis(DEA)model to measure the environmental efficiency of 12 U.S.airlines 2013–2016 by considering flight delay and greenhouse gas(GHG)emissions as joint undesirable outputs.First,the environmental efficiency of airlines is compared using the CCR DEA(without flight delay)and DDF DEA(with flight delay).We find that several airlines experienced substantial changes in environmental efficiency scores when flight delay is considered.Secondly,a tobit regression is used to explore whether the environmental factors of fleet age,ownership type,freight traffic,market share,and carrier type affect airlines’environmental efficiency.The results demonstrate that all of these factors significantly influence airline performance.展开更多
文摘OBJECTIVE: To compare the effects of a Chinese herbal suppository(Jianpi suppository) and Western Medicine(mesalazine) on hemorheology and CD62p in patients with ulcerative colitis(UC).METHODS: In a randomized trial, 120 mild to moderate UC patients were randomly divided into two equal groups. The Jianpi suppository group used Chinese herbal suppository rectally, while the mesalazine group was treated with mesalazine tablets orally. Two 15-day courses of treatment were carried out in both groups. Changes in the hemorheology and CD62p indices in patients were observed.RESULTS: The hemorheology and CD62p indices in the Jianpi suppository group decreased significantly more than those of the mesalazine group.CONCLUSION: Jianpi suppository is effective in improving the hypercoagulability of UC patients, and therefore may be worth using in clinical practice.
基金supported by the National Key Basic Research Program of China (No.2004CB418503)the National Natural Science Foundation of China (No.40801203)
文摘Due to frequent soil Cd contamination and wide use of butachlor in China,there is a need to assess their combined toxicity to soil microorganisms.The combined effects of cadmium(Cd,10 mg kg-1 soil) and herbicide butachlor(10,50,and 100 mg kg-1 soil) on enzyme activities and microbial community structure in a paddy soil were assessed using the traditional enzyme assays and random amplified polymorphic DNA(RAPD) analysis.The results showed that urease and phosphatase activities were significantly reduced by high butachlor concentration(100 mg kg-1 soil).When the concentrations of Cd and butachlor added were at a ratio of 1:10,urease and phosphatase activities were significantly decreased whereas enzyme activities were greatly improved at the ratio of 1:5,which indicated that the combined effects of Cd and butachlor on soil urease and phosphatase activities depended largely on their addition concentration ratios.Random amplified polymorphic DNA(RAPD) analysis showed loss of original bands and appearance of new bands when compared with the control soil.Random amplified polymorphic DNA fingerprints suggested substantial differences between the control and treated soil samples,with apparent changes in the number and size of amplified DNA fragments.The addition of high concentration butachlor and the combined impacts of Cd and butachlor significantly affected the diversity of the microbial community.RAPD analysis in conjunction with other biomarkers such as soil enzyme parameters would prove a powerful ecotoxicological tool.Further investigations should be carried out to understand the clear link between RAPD patterns and enzyme activity.
基金This study has been supported by the National Natural Science Foundation of China under Grant No. 40633014.
文摘It has been proved that there exists a cross coupling between vertical heat turbulent transport and vertical velocity by using linear thermodynamics. This result asserts that the vertical component of heat turbulent transport flux is composed of both the transport of the vertical potential temperature gradient and the coupling transport of the vertical velocity. In this paper, the coupling effect of vertical velocity on vertical heat turbulent transportation is validated by using observed data from the atmospheric boundary layer to determine cross coupling coefficients, and a series of significant properties of turbulent transportation are opened out. These properties indicate that the cross coupling coefficient is a logarithm function of the dimensionless vertical velocity and dimensionless height, and is not only related to the friction velocity u., but also to the coupling roughness height zwo and the coupling temperature Two of the vertical velocity. In addition, the function relations suggest that only when the vertical velocity magnitude conforms to the limitation IW/u. I # 1, and is above the level zwo, then the vertical velocity leads to the cross coupling effect on the vertical heat turbulent transport flux. The cross coupling theory and experimental results provide a challenge to the traditional turbulent K closure theory and the Monin-Obukhov similarity theory.
基金Supported by the Project of Rural Environmental Pollution Prevention and Control Engineering R&D Center of Jiangsu ProvinceScientifi and Technological Service Platform for Agricultural Environmental Pollution Prevention and Control of Nantong City (DE2009006)2010 Soft Science Project of Nantong Association of Science and Technology(RK2010-05)
文摘Developing the low carbon ecological circular agriculture is an effective approach to realizing low carbon development of agriculture. Through investigation on existing measures and performance of development of low carbon type ecological circular agriculture in Nantong City, we analyzed the potential and problems of Nantong City in developing low carbon type ecological circular agriculture. Finally, with reference to domestic and foreign research achievements and practical experience, we put forward countermeasures for developing low carbon type ecological circular agriculture in Nantong City from building technical system and government guidance.
基金the National Basic Research Program of China(2009CB724700)the Foundation of Jiangsu Province of China for College Postgraduate Students in Innovation Engineering(CXZZ12_0440)
文摘Magnetically modified palygorskite composites were synthesized with γ-Fe2O3 dispersing on the external surface of clay mineral. The magnetic clay was characterized with Fourier transform infrared, X-ray diffrac- tion, transmission electron microscopy, and vibrating sample magnetometer. Candida sp. 99-125 lipase was immobilized on magnetic palygorskite composites by physical adsorption with enzyme loading of 41.5 mg· g^-1 support and enzyme activity of 2631.6 U· （g support）^-1. The immobilized lipase exhibit better thermal and broader pH stability and excellent reusabilitV compared with free lipase.
基金self-supported as part of the Ph D Program on CSC scholarship in the China University of Geosciences (Wuhan)
文摘In a developing country like Ghana, the study of land use and land cover change(LULCC) based on satellite imageries still remains a challenge due to cost, resolution and availability with less skilled man power. Existing researches are skewed towards the southerly part of Ghana thereby leaving the Northern sectors uncovered. The maximum likelihood classification(MLC) algorithm was employed for the LULCC between 2000 and 2014 in Nadowli: an area characterized by an upsurge in mining in the Northern belt of Ghana. A spatial-social approach was utilized combining both satellite imagery and socio economic data. Land use transition matrix, land use integrated index/degree indices was used to depict the characters of the change. A semi structured interview, pair wise ranking and key informant interviews were used to correlate the socio economic impact of the different LULC. Overall changes in the landscape showed an increase in bare ground by 19.22%, open savannah by 16.8% whereas closed savanna decreased by 50%. Land use change matrix showed increasing trends of bare ground at the expense of vegetation. The integrated land use index highlighted the bare ground and built up areas rising with a decreasing closed vegetation woodlot. Large farm size are shrinking whiles majority of the people view mining as the main socio economic activity affecting the environment and the reduction in vegetation. This study therefore provides a strategic guide and a baseline data for land use policy actors in the Northern belt of Ghana. This will aid in developing models for future land use change implications in surrounding areas where mining is on the rise.
文摘Naturally-occurring and artificially-induced polyploids have been documented in various fish species but to date no comparison has been reported of the impacts of ploidy on fish biomarker responses to organic pollutants.This study describes effects of ploidy,gender,and dose on biliary fluorescent aromatic compound（FAC） concentrations,hepatic ethoxyresorufin-O-deethylase（EROD） and glutathione S-transferase（GST） activities in one of the most commonly cultured warm-water species,the African catfish Clarias gariepinus.Recently matured male and female diploid and triploid fish were intraperitoneally（i.p.）injected with 0,5 or 25 mg/kg benzo[a]pyrene（BaP） and liver and gallbladder were sampled48 hr later.No significant differences were found between ploidies in bile concentrations of7,8 dihydrodiolbenzo[a]pyrene（7,8D BaP）,1-hydroxybenzo[a]pyrene（1-OH BaP） or3-hydroxybenzo[a]pyrene（3-OH BaP）.However,concentrations of the biliary FACs did differ between males and females at different dose of injection with generally higher concentrations in females at the low dose of BaP and higher concentrations in males at the higher BaP concentration.Hepatic EROD activity did not exhibit gender-dependent difference,whereas it was significantly higher in triploids than diploids.GST activities were not significantly influenced by any of the tested factors.This work advanced our understanding of the role of ploidy,gender,and dose in biotransformation of pollutants in fish.
文摘Bacterial leaf blight(BLB)and bacterial leaf streak(BLS),caused by Xanthomonas oryzae pv.oryzae(Xoo)and X.oryzae pv.oryzicola(Xoc),respectively,lead to severe loss in yields and quality in most rice-growing areas around the world.As the staple crop and the model plant for biology research,characterizing the diseases of rice has great significance.It is crucial to elucidate the interaction between the pathogens and rice as well as the mechanisms of pathogenesis and resistance.The special topic of the three papers is the pathogenicity of plant pathogenic bacteria and host resistance to pathogens.
基金Federal Ministry of Education and Research (BMBF) of Germany,funded the PhD programme of the lead author through the West African Science Service Centre for Climate Change and Adapted Land use (WASCAL)。
文摘Background: Modelling aboveground biomass(AGB) in forest and woodland ecosystems is critical for accurate estimation of carbon stocks. However, scarcity of allometric models for predicting AGB remains an issue that has not been adequately addressed in Africa. In particular, locally developed models for estimating AGB in the tropical woodlands of Ghana have received little attention. In the absence of locally developed allometric models, Ghana will continue to use Tier 1 biomass data through the application of pantropic models. Without local allometric models it is not certain how Ghana would achieve Tier 2 and 3 levels under the United Nations programme for reducing emissions from deforestation and forest degradation. The objective of this study is to develop a mixedspecies allometric model for use in estimating AGB for the tropical woodlands in Ghana. Destructive sampling was carried out on 745 trees(as part of charcoal production) for the development of allometric equations. Diameter at breast height(dbh, i.e. 1.3 m above ground level), total tree height(H) and wood density(ρ) were used as predictors for the models. Seven models were compared and the best model selected based on model efficiency,bias(%) and corrected Akaike Information Criterion. The best model was validated by comparing its results with those of the pantropic model developed by Chave et al.(Glob Chang Biol 20:3177–3190, 2014) using equivalence test and conventional paired t-test.Results: The results revealed that the best model for estimating AGB in the tropical woodlands is AGB =0.0580ρ((dbh)2 H)0.999. The equivalence test showed that this model and the pantropic model developed by Chave et al.(Glob Chang Biol 20:3177–3190, 2014) were equivalent within ±10% of their mean predictions(p-values <0.0001 for one-tailed t-tests for both lower and upper bounds at 5% significant level), while the paired t-test revealed that the mean(181.44 ± 18.25 kg) of the model predictions of the best model of this study was significantly(n = 745, mean diff. = 16.50 ± 2.45 kg;S.E. = 1.25 kg;p < 0.001) greater than that(164.94 ± 15.82 kg) of the pantropic model of Chave et al.(Glob Chang Biol 20:3177–3190, 2014).Conclusion: The model developed in this study fills a critical gap in estimating AGB in tropical woodlands in Ghana and other West African countries with similar ecological conditions. Despite the equivalence with the pantropic model it remains superior to the model of Chave et al.(Glob Chang Biol 20:3177–3190, 2014) for the estimation of AGB in local tropical woodlands. It is a relevant tool for the attainment of Tier 2 and 3 levels for REDD+. The model is recommended for use in the tropical woodlands in Ghana and other West African countries in place of the use of pantropic models.
文摘OBJECTIVE: This article investigates the methods of achieving deep remission of inflammatory bowel disease (IBD). METHODS: Increasing recognition of the concept of quality of care is contributing to the evolution of treatment goals in patients with IBD from clinical response and remission (symptom control) toward deep remission. A change in the treatment goal requires a change in the treatment strategy. Optimization of conventional therapy, early treatment, use of the Lemann score, performance of double-balloon endoscopy, treatment using Traditional Chinese Medicine, and good communication between physicians and patients are needed to attain deep remission. RESULTS: The above-mentioned methods can help to achieve deep remission. CONCLUSION: Using the above methods, it will bepossible to improve the prognoses of patients with IBD by minimizing complications and bowel damage and thereby changing the course of the disease.
文摘Bleeding canker (BC) of pear trees, is a devastating disease in China. The disease was originally observed in Jiangsu Province and its causal agent was identified first as Erwinia sp. in the early 1970's and latter as a novel species, Dickeya fangzhongdai. BC is epidemically emerging prevalently from April to September annually in pear-growing regions in Zhejiang, Anhui and Shandong provinces, and threatening pear industry currently in China. To better control BC disease, it is crucial to know BC symptomatology, epidemics, etiology, and diagnostics first. The special topic of the three papers have well illustrated the points mentioned above.
文摘The study assesses the quality of hand dug wells in relation to distance from soakaway septic tanks in three selected peri-urban communities in the Ga West Municipality near Accra, Ghana. Water quality analyses of bio-physico-chemical variables (pH, Temperature, EC, turbidity, DO, BOD, TSS, TDS, sodium, potassium, nitrate, nitrite, ammonia, sulphate, chloride, salinity, total alkalinity, total coliform, fecal coliforms and isolation of <i>E. coli</i>) were determined. Concentrations of the major nutrient anion sulphate, nitrate, phosphate, and chlorides in water samples at distances between 0</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">30 m radial distances from the septic tank were above the WHO permissible limit of drinking water compared to the control. All the water samples had high fecal and total coliform counts that exceeded the international standard of 0 per 100 mL of potable water with counts ranging from 0</span><span style="font-family:""> - </span><span style="font-family:"">143</span><span style="font-family:""> </span><span style="font-family:"">cfu/100</span><span style="font-family:""> </span><span style="font-family:"">ml and 53</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">463/100</span><span style="font-family:""> </span><span style="font-family:"">ml for FC and TC respectively. High fecal coliform and detection of <i>E. coli</i> in most samples is an indication of fecal pollution possibly from their close proximity to soak away septic sewage. The high nutrient levels detected in samples at distances between 0</span><span style="font-family:""> </span><span style="font-family:"">-</span><span style="font-family:""> </span><span style="font-family:"">30</span><span style="font-family:""> </span><span style="font-family:"">m as compared to the controls may also be attributed to its close proximity to septic tanks. This study, therefore, accentuates the need for the owners of the water points to site their water source at least 30m away </span><span style="font-family:"">from </span><span style="font-family:"">localized sources of pollution as well as treatment of groundwater before use.
基金supported by the National Key R&D Program of China (2017YFD0200400)the National Natural Science Foundation of China (31772122 and 31470235)
文摘Xanthomonas oryzea pv.oryzae(Xoo)is the causal agent of bacterial blight of rice,which is a significant threat to many of rice-growing regions.The type Ⅲ secretion system(T3SS)is an essential virulence factor in Xoo.Expression of the T3SS is often induced in the host environment or in hrp-inducing medium but is repressed in nutrient-rich medium.The elucidation of molecular mechanism underlying induction of T3SS genes expression is a very important step to lift the veil on global virulence regulation network in Xoo.Thus,an efficient and reliable genetic tool system is required for detection of the T3SS proteins.In this study,we constructed a protein expression vector pH3-flag based on the backbone of pHM1,a most widely used vector in Xoo strains,especially a model strain PXO99A.This vector contains a synthesized MCS-FLAG cassette that consists of a multiple cloning site(MCS),containing a modified pUC18 polylinker,and Flag as a C-terminal tag.The cassette is flanked by transcriptional terminators to eliminate interference of external transcription enabling detection of accurate protein expression.We evaluated the potential of this expression vector as T3SS proteins detection system and demonstrated it is applicable in the study of T3SS genes expression regulation in Xoo.This improved expression system could be very effectively used as a molecular tool in understanding some virulence genes expression and regulation in Xoo and other Xanthomonas spp.
文摘This study applies a directional distance function(DDF)data envelopment analysis(DEA)model to measure the environmental efficiency of 12 U.S.airlines 2013–2016 by considering flight delay and greenhouse gas(GHG)emissions as joint undesirable outputs.First,the environmental efficiency of airlines is compared using the CCR DEA(without flight delay)and DDF DEA(with flight delay).We find that several airlines experienced substantial changes in environmental efficiency scores when flight delay is considered.Secondly,a tobit regression is used to explore whether the environmental factors of fleet age,ownership type,freight traffic,market share,and carrier type affect airlines’environmental efficiency.The results demonstrate that all of these factors significantly influence airline performance.
