Helicobacter pylori are ubiquitous Gram-negative bacteria with a high estimated level of infection in the world populations, but a majority of the infected persons are asymptomatic. This pathogen has been classified b...Helicobacter pylori are ubiquitous Gram-negative bacteria with a high estimated level of infection in the world populations, but a majority of the infected persons are asymptomatic. This pathogen has been classified by the World Health Organization as a class I carcinogen and recognized as the causal agent of most peptic ulcers and chronic gastritis that might lead to stomach cancer. Although not all the transmission pathways of these bacteria into humans have been propedy identified, enough data have suggested that the oral-oral or fecal-oral ones are the main infection routes. Helicobacterpylori have been detected in non-treated water and in drinking water, which suggested that water might be an important infection source. As childhood is the critical period of infection, the aim of the present work was to examine the presence of Helicobacterpylori in soil samples from public playing areas of Spanish parks.展开更多
In this paper,the structure of 'double juts' soil sampler and a series of new soil samplers are introduced.The internal diameter of auger tip the sampler is less than that of sampling tube, but the external di...In this paper,the structure of 'double juts' soil sampler and a series of new soil samplers are introduced.The internal diameter of auger tip the sampler is less than that of sampling tube, but the external diameterof auger tip is larger than that of sampling tube. Therefore, adhesion and cutting resistance can be reducedby limiting connection areas between sampler and the soil. Such a new structure makes it possible to bewidely used for the production of a series of special soil samplers.展开更多
The most important parameter affecting ground-penetrating radar （GPR） measurements is the complex effective relative permittivity εr^＊,eff because it controls the propagation velocity and the reflection of GPR pul...The most important parameter affecting ground-penetrating radar （GPR） measurements is the complex effective relative permittivity εr^＊,eff because it controls the propagation velocity and the reflection of GPR pulses. Knowing εr^＊,eff of soils passed through by electromagnetic waves increases accuracy in soil thickness and interface identification. Complex effective relative permittivity εr^＊,eff= εr^＊,eff - jεr^＊,effof 25 soil samples with textures ranging from loamy sand to silty clay was measured using the two-electrode parallelplate method. The measurements were conducted at defined water contents for frequencies from 1 MHz to 3 GHz. The results confirm the frequency dependence of εr^＊,eff and show that the dielectric behavior of soil-water mixtures is a function of water content. Applying the experimental data of this study with predictions based on the empirical model by Toppet aL （1980）, we find that Topp et aL＇s curve tends to underestimate the real part of εr^＊,eff measured. Along with frequency and water content, soil texture and organic matter affect soil permittivity. Moreover, the real part of εr^＊,eff increases at higher dry bulk densities. Output from our calibration model enables us to predict εr^＊,eff for the soil samples which were tested under the actual in situ soil water content. This results in high accuracy of soil thickness prediction.展开更多
Through the analysis on the migratory diffusion process of atmospheric pollutants,we proposed to seek atmospheric pollutant source with surface soil sample of data.Based on Gaussian plume model and deposition model,at...Through the analysis on the migratory diffusion process of atmospheric pollutants,we proposed to seek atmospheric pollutant source with surface soil sample of data.Based on Gaussian plume model and deposition model,atmospheric pollutants distribution model was deduced,with which a schema matching source seeking model was established.The model was used to seek the pollutant source by using the arsenic data in the surface soil sample of a city.展开更多
This study was designed to screen and characterize antibiotic producing bacteria and fungi from soil samples from a waste dump site in Enugu. The molecular characterization of the isolates was performed by using Zymo ...This study was designed to screen and characterize antibiotic producing bacteria and fungi from soil samples from a waste dump site in Enugu. The molecular characterization of the isolates was performed by using Zymo Research Quick-DNA fungi/bacteria miniprep kit. The bacteria isolates were <i>Providencia stuartii</i>, <i>Providencia alcalifaciens.</i> <i>Bacillus sp.</i>, <i>Streptococcus sp.</i>, <i>Micrococcus sp.</i>, and <i>Staphylococcus sp</i> while <i>Aspergillus fumigatus</i> and <i>Aspergillus niger</i> were fungal isolates. The efficacy of the Crude Extract (CE) of the antibiotics produced was tested against species of <i>Staphylococcus aureus</i> and <i>Escherichia coli</i>. The CE of antibiotics when compared with a conventional antibiotic (Ciprofloxacin) showed lower antimicrobial activity. The minimum inhibitory concentration of the crude extracts ranged between 12.5% and 25% concentrations while the minimum bactericidal concentration ranged from 25% and 50% concentrations. The findings suggest that these organisms have the potential to produce antibiotics and could be harnessed by pharmaceutical industries for the production of newer antibiotics.展开更多
A very simple, ultra-sensitive, highly selective and non-extractive new spectrofluorimetric method for the determination of arsenic at pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been develope...A very simple, ultra-sensitive, highly selective and non-extractive new spectrofluorimetric method for the determination of arsenic at pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been developed. PTQA has been proposed as a new analytical reagent for the direct non-extractive spectrofluorimetric determination of Arsenic (V). This novel fluorimetric reagent, PTQA becomes oxidized in a slightly acidic (0.025 - 0.1 M H2SO4) solution with Arsenic (V) in absolute ethanol to produce highly fluorescent oxidized product (λex = 303 nm;λem = 365 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.025 - 0.1 M H2SO4) for the period between 2 min and 24 h. Linear calibration graphs were obtained for 0.001 - 800-μgL-1 of As, having a detection limit of 0.1-ngL-1;the quantification limit of the reaction system was found to be 1-ngL-1 and the RSD was 0% - 2%. A large excess of over 60 cations, anions and complexion agents (like, chloride, phosphate, azide, tartrate, oxalate, SCN, etc.) do not interfere in the determination. The developed method was successfully used in the determination of arsenic in several Certified Reference Materials (alloys, steels, ores, human urine, hair, nails, bovine liver and sediments) as well as in some biological fluids (human blood, urine, hair, nail and milk), soil samples, food samples (vegetables, fruits, rice, corn and wheat), solutions containing both arsenic (III) and arsenic (V) speciation and complex synthetic mixtures. The results of the proposed method for assessing biological, food and soil samples were comparable with both ICP-OES & AHG-AAS and were found to be in excellent agreement.展开更多
Erratum to 19(5):760-781 Frontiers ofStructural and Civil Engineering 2025,https://doi.org/10.1007/s11709-025-1168-5 The article“Interpretable artificial intelligence approach for understanding shear strength in stab...Erratum to 19(5):760-781 Frontiers ofStructural and Civil Engineering 2025,https://doi.org/10.1007/s11709-025-1168-5 The article“Interpretable artificial intelligence approach for understanding shear strength in stabilized clay soils using real field soil samples”,written by Mohamed Noureddin,Aghyad Al Kabbani,Alejandra Lopez,and Leena Korkiala-Tanttu,was originally published electronically on the publisher's internet portal on May 30,2025 without open access due to an unfortunate oversight during the conversion process.展开更多
Soil microorganisms play globally vital roles in the environment,ecology,and agriculture[1],and have become a research hotspot.Most research in these fields depends on microbial sequencing and analysis[2,3],which shou...Soil microorganisms play globally vital roles in the environment,ecology,and agriculture[1],and have become a research hotspot.Most research in these fields depends on microbial sequencing and analysis[2,3],which should ideally be conducted immediately after sample collection[4].However on-site DNA extraction and sequencing are often impractical.Therefore,freshly collected soil samples must be properly stored for transport before sequencing.While this sounds like a natural operation,proper transport of soil samples has been widely overlooked,challenging the accuracy of all related research.展开更多
基金supported by the Ministry of Education and Science of Spain(No.CTM2005-106457-C05-05/TECNO),FPI grant from Ministry of Education and Science of Spain,and FI grant from the Comissionat per a Universitats i Recerca del Departament d'Innovació,Universitats i Empresa de la Generalitat de Catalunya i del Fons Social Europeu
文摘Helicobacter pylori are ubiquitous Gram-negative bacteria with a high estimated level of infection in the world populations, but a majority of the infected persons are asymptomatic. This pathogen has been classified by the World Health Organization as a class I carcinogen and recognized as the causal agent of most peptic ulcers and chronic gastritis that might lead to stomach cancer. Although not all the transmission pathways of these bacteria into humans have been propedy identified, enough data have suggested that the oral-oral or fecal-oral ones are the main infection routes. Helicobacterpylori have been detected in non-treated water and in drinking water, which suggested that water might be an important infection source. As childhood is the critical period of infection, the aim of the present work was to examine the presence of Helicobacterpylori in soil samples from public playing areas of Spanish parks.
文摘In this paper,the structure of 'double juts' soil sampler and a series of new soil samplers are introduced.The internal diameter of auger tip the sampler is less than that of sampling tube, but the external diameterof auger tip is larger than that of sampling tube. Therefore, adhesion and cutting resistance can be reducedby limiting connection areas between sampler and the soil. Such a new structure makes it possible to bewidely used for the production of a series of special soil samplers.
基金supported by the German Research Foundation (DFG) (No. SFB 299)
文摘The most important parameter affecting ground-penetrating radar （GPR） measurements is the complex effective relative permittivity εr^＊,eff because it controls the propagation velocity and the reflection of GPR pulses. Knowing εr^＊,eff of soils passed through by electromagnetic waves increases accuracy in soil thickness and interface identification. Complex effective relative permittivity εr^＊,eff= εr^＊,eff - jεr^＊,effof 25 soil samples with textures ranging from loamy sand to silty clay was measured using the two-electrode parallelplate method. The measurements were conducted at defined water contents for frequencies from 1 MHz to 3 GHz. The results confirm the frequency dependence of εr^＊,eff and show that the dielectric behavior of soil-water mixtures is a function of water content. Applying the experimental data of this study with predictions based on the empirical model by Toppet aL （1980）, we find that Topp et aL＇s curve tends to underestimate the real part of εr^＊,eff measured. Along with frequency and water content, soil texture and organic matter affect soil permittivity. Moreover, the real part of εr^＊,eff increases at higher dry bulk densities. Output from our calibration model enables us to predict εr^＊,eff for the soil samples which were tested under the actual in situ soil water content. This results in high accuracy of soil thickness prediction.
文摘Through the analysis on the migratory diffusion process of atmospheric pollutants,we proposed to seek atmospheric pollutant source with surface soil sample of data.Based on Gaussian plume model and deposition model,atmospheric pollutants distribution model was deduced,with which a schema matching source seeking model was established.The model was used to seek the pollutant source by using the arsenic data in the surface soil sample of a city.
文摘This study was designed to screen and characterize antibiotic producing bacteria and fungi from soil samples from a waste dump site in Enugu. The molecular characterization of the isolates was performed by using Zymo Research Quick-DNA fungi/bacteria miniprep kit. The bacteria isolates were <i>Providencia stuartii</i>, <i>Providencia alcalifaciens.</i> <i>Bacillus sp.</i>, <i>Streptococcus sp.</i>, <i>Micrococcus sp.</i>, and <i>Staphylococcus sp</i> while <i>Aspergillus fumigatus</i> and <i>Aspergillus niger</i> were fungal isolates. The efficacy of the Crude Extract (CE) of the antibiotics produced was tested against species of <i>Staphylococcus aureus</i> and <i>Escherichia coli</i>. The CE of antibiotics when compared with a conventional antibiotic (Ciprofloxacin) showed lower antimicrobial activity. The minimum inhibitory concentration of the crude extracts ranged between 12.5% and 25% concentrations while the minimum bactericidal concentration ranged from 25% and 50% concentrations. The findings suggest that these organisms have the potential to produce antibiotics and could be harnessed by pharmaceutical industries for the production of newer antibiotics.
文摘A very simple, ultra-sensitive, highly selective and non-extractive new spectrofluorimetric method for the determination of arsenic at pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been developed. PTQA has been proposed as a new analytical reagent for the direct non-extractive spectrofluorimetric determination of Arsenic (V). This novel fluorimetric reagent, PTQA becomes oxidized in a slightly acidic (0.025 - 0.1 M H2SO4) solution with Arsenic (V) in absolute ethanol to produce highly fluorescent oxidized product (λex = 303 nm;λem = 365 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.025 - 0.1 M H2SO4) for the period between 2 min and 24 h. Linear calibration graphs were obtained for 0.001 - 800-μgL-1 of As, having a detection limit of 0.1-ngL-1;the quantification limit of the reaction system was found to be 1-ngL-1 and the RSD was 0% - 2%. A large excess of over 60 cations, anions and complexion agents (like, chloride, phosphate, azide, tartrate, oxalate, SCN, etc.) do not interfere in the determination. The developed method was successfully used in the determination of arsenic in several Certified Reference Materials (alloys, steels, ores, human urine, hair, nails, bovine liver and sediments) as well as in some biological fluids (human blood, urine, hair, nail and milk), soil samples, food samples (vegetables, fruits, rice, corn and wheat), solutions containing both arsenic (III) and arsenic (V) speciation and complex synthetic mixtures. The results of the proposed method for assessing biological, food and soil samples were comparable with both ICP-OES & AHG-AAS and were found to be in excellent agreement.
文摘Erratum to 19(5):760-781 Frontiers ofStructural and Civil Engineering 2025,https://doi.org/10.1007/s11709-025-1168-5 The article“Interpretable artificial intelligence approach for understanding shear strength in stabilized clay soils using real field soil samples”,written by Mohamed Noureddin,Aghyad Al Kabbani,Alejandra Lopez,and Leena Korkiala-Tanttu,was originally published electronically on the publisher's internet portal on May 30,2025 without open access due to an unfortunate oversight during the conversion process.
基金supported by the National Natural Science Foundation of China(42320104002)the Jiangsu Agriculture Science and Technology Innovation Fund(JASTIF,CX(22)1003)the Original Innovation Project of Chinese Academy of Sciences(ZDBS-LY-DQC024)。
文摘Soil microorganisms play globally vital roles in the environment,ecology,and agriculture[1],and have become a research hotspot.Most research in these fields depends on microbial sequencing and analysis[2,3],which should ideally be conducted immediately after sample collection[4].However on-site DNA extraction and sequencing are often impractical.Therefore,freshly collected soil samples must be properly stored for transport before sequencing.While this sounds like a natural operation,proper transport of soil samples has been widely overlooked,challenging the accuracy of all related research.
