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1.
Biol Res Nurs ; 26(1): 125-138, 2024 01.
Article in English | MEDLINE | ID: mdl-37579279

ABSTRACT

OBJECTIVE: This study aimed to investigate the effects of aerobic interval training and resistance training on anti-inflammatory adipokines, high sensitivity C-reactive protein, and clinical outcomes in sedentary men with metabolic syndrome. METHODS: A total of 33 sedentary men with metabolic syndrome (age: 46.2 ± 4.6 years; body mass index: 35.4 ± 1.9 kg.m2) were randomly assigned to one of 3 groups: aerobic interval training (n = 12), resistance training (n = 10), or control (n = 11). Participants in the exercise groups completed a 12-week training program, 3 sessions per week, while those in the control group maintained their sedentary lifestyle. The levels of high sensitivity C-reactive protein (hs-CRP), omentin-1, adiponectin, lipid profiles, blood pressure, glucose metabolism, body composition, and peak oxygen uptake (VO2peak) were measured at baseline and after the intervention. RESULTS: Both aerobic interval training and resistance training significantly improved the levels of omentin-1 and adiponectin, as well as reduced inflammation, as indicated by a decrease in hs-CRP levels. Exercise training also led to significant improvements in lipid profiles, blood pressure, glucose metabolism, and body composition. Specifically, the aerobic interval training group had significantly greater increases in high-density lipoprotein cholesterol and VO2peak, as well as greater reductions in low-density lipoprotein cholesterol, triglycerides, and total cholesterol compared to the resistance training group. CONCLUSION: Exercise training, particularly aerobic interval training and resistance training, can be an effective non-pharmacological intervention for managing inflammation and improving cardiovascular health in metabolic syndrome patients.


Subject(s)
C-Reactive Protein , Metabolic Syndrome , Adult , Humans , Male , Middle Aged , Adipokines , Adiponectin , Anti-Inflammatory Agents , C-Reactive Protein/analysis , Cholesterol , Exercise/physiology , Glucose , Inflammation , Metabolic Syndrome/therapy , Triglycerides
2.
J Environ Sci (China) ; 113: 300-310, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34963539

ABSTRACT

Visibility observed at different altitudes is favorable to understand the causes of air pollution. We conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter (PM) concentrations from 2015 to 2018 in Shenyang, a provincial city in Northeast China. The results indicated that visibility increased with the increasing height in winter (especially at night), and decreased with height in summer (especially at the daytime). PM concentration exhibited opposite vertical variation to visibility, reflecting that visibility degrades with the increase of aerosol concentration in the air. The radiosonde meteorological data showed that weak turbulence in the planetary boundary layer (PBL) in winter favored aerosols' accumulation near the surface. Whereas in summer, unstable atmospheric conditions, upper-level moister environment, and regional transport of air pollutants resulted in the deterioration of upper-level visibility. Inter-annual variation in the two-level visibility indicated that the upper-level visibility improved more significantly than low-level visibility, much likely due to the reduction in emission of elevated point sources in Shenyang. Our study suggested that strengthening the control of surface non-point emissions is a promising control strategy to improve Shenyang air quality.


Subject(s)
Air Pollutants , Air Pollution , Aerosols/analysis , Air Pollutants/analysis , Air Pollution/analysis , China , Environmental Monitoring , Particulate Matter/analysis , Seasons
3.
J Environ Manage ; 280: 111794, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33341472

ABSTRACT

A community of aquatic macrophytes has an important role in reducing nutrient load and organic and inorganic contaminants in storm/runoff water. However, minimal information is available regarding the efficiency of constructed wetlands for cleaning runoff water from urban areas, especially in the tropical and subtropical regions. This study investigated the effectiveness of constructed wetland integrated with aquatic macrophytes for removal of chemical and microbial contaminants in the storm/runoff water from the urban areas. Water samples were monthly collected in the constructed wetland from the inlet of storm/runoff water, middle and outlet of discharge, and analyzed for physical and chemical properties, concentrations of nutrients, metals, and fecal coliform (FC) during the period of November, 2016 to April, 2018 in St. Lucie county, Florida, USA. The dominant plant species in the constructed wetland included cattail (Typha latifolia), waterthyme (Hydrilla verticillata) and water hyacinth (Eichhornia crassipes), and periphyton filamentous algae (Spirogyra). The improvement of pH and electrical conductivity (EC) was not obvious, but the concentration of total suspended solids was significantly reduced. This system was effective in the removal of fecal coliform (by 68%) and particulate phosphorus (P, 72%), followed by total P (42%) and N (35%). Concentrations of metallic pollutants including cadmium (Cd), lead (Pb), chromium (Cr), and copper (Cu) were mostly below the detection limit (<1 ppb) except for zinc (Zn), of which concentration was reduced by 23%. The removal of FC was consistently effective all the year round, whereas the removal of total N, P and particulate-P was effective in spring and summer, and less in autumn and winter. These results indicate that constructed wetland with a natural aquatic plant community can effectively reduce the loads of nutrients, metals, and fecal coliforms in water column. Regular harvest of aquatic macrophytes communities and collecting litters may further improve the system efficiency for cleaning storm water from urban areas.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Florida , Metals, Heavy/analysis , Water , Water Pollutants, Chemical/analysis , Wetlands
4.
Sci Total Environ ; 635: 878-891, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-29710610

ABSTRACT

Decaying experiments of four major aquatic macrophyte detritus, namely cattail (Typha orientalis), water lettuce (Pistia stratiotes), hydrilla (Hydrilla verticillata) and maidencane (Panicum hemitomon), were conducted using the litterbag technique in the stormwater detention pond of South Florida, USA. Dry weight and chemical composition of remaining biomass were dynamically determined during the 185-day decay experiment. The results showed that decomposition rates (k), and the derived turnover (t50% and t95%) were species specific. The k values decreased in the order of hydrilla (0.0123 g day-1) > water lettuce (0.0082 g day-1) > maidencane (0.0049 g day-1) > cattail (0.0031 g day-1), whereas t50% and t95% varied in the reverse way. Biomass properties including concentrations of C, N, P, lignin, cellulose, hemicellulose, and the ratios of C/N, C/P, N/P and lignin/N affected decaying rate of the studied aquatic plants. The dry mass loss and concentrations of C, N, P, lead (Pb), chromium (Cr), copper (Cu), manganese (Mn), zinc (Zn), lignin, cellulose, hemicellulose and ratios C/N, C/P, N/P and Lignin/N of plant detritus were significantly affected by species, decaying time, and their interactions. However, the influence of species differences was greater than that of decaying time on those indexes. The estimated amounts (kg) of nutrients and metals released based on k values for the waterways of the IRL basin (water surface area 15.6 km2) were N 126.85 × 103, P 8.89 × 103, Zn 408.20, Pb 97.95, Cr 128.99, Mn 313.03, and Cu 82.40. Water lettuce contributed most, accounting for 52.13% N, 56.81% P, 74.95% Zn, 59.58% Pb, and 74.65% Mn, followed by hydrilla, cattail and maidencane. For Cr and Cu, cattail had the greatest contribution of 65.77% and 54.15%, respectively, followed by water lettuce, hydrilla and maidencane.


Subject(s)
Araceae/physiology , Environmental Monitoring , Water Pollutants, Chemical/analysis , Biodegradation, Environmental , Biomass , Chromium , Florida , Metals , Nitrogen/analysis , Poaceae , Rivers/chemistry
5.
Water Res ; 137: 375-383, 2018 06 15.
Article in English | MEDLINE | ID: mdl-29555116

ABSTRACT

Leaching of dissolved organic nitrogen (DON) has been reported as a pathway of N loss from agriculture, but the molecular composition of DON in agricultural water is poorly understood. Runoff water samples were collected from citrus grove furrows (CGF), ditches (CGD) and pasture ditches (PD) in four seasons. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) was used to investigate molecular composition of DON. Chemodiversity index of DON had spatiotemporal variations, while the molecular composition of total DON showed minimal variations, except for PD in November. Lignin derivatives constituted 61% of the total DON compounds. Relative abundance of aliphatic compounds, char and condensed aromatics of unique DON compounds varied spatiotemporally and had a significant correlation with DON concentration. Aromaticity index decreased from CGF to connected CGD, implying that photodegradation is possibly the dominant process that alters molecular composition of aquatic DON during the transport. Significant differences in unique DON composition between CGD and PD indicates that fertilization and land use affect DON composition. The information on molecular characterization of DON should be useful for tracking DON source and developing technologies to remove DON in the agricultural runoff water.


Subject(s)
Agriculture , Nitrogen/analysis , Water/analysis , Citrus , Florida , Mass Spectrometry/methods , Nitrogen/chemistry , Seasons , Spatio-Temporal Analysis , Spectroscopy, Fourier Transform Infrared/methods , Water/chemistry
6.
Anim Sci J ; 88(8): 1232-1238, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28078817

ABSTRACT

The aim of this study was to evaluate fertility and sex ratios after artificial insemination in dogs under field conditions. Semen was cryopreserved as unsorted (control) or was separated into X- and Y-chromosome-bearing sperm using a cell sorter. Sixty female dogs were inseminated with frozen-thawed spermatozoa of 100 × 106 unsorted (a dose in practice) and 4 × 106 sorted (X and Y group, respectively). A total of 20 dogs became pregnant and 126 puppies were born from the three groups. The percentage of parturition was similar for the X (5/20; 25.0%) and Y (4/20; 20.0%) group (P > 0.05), but lower than controls (11/20; 55.0%) (P < 0.05). Ultimately 28 out of the 32 puppies produced from X group were female (87.5%) and 19/22 (86.4%) puppies of Y group were male. In contrast, sex ratio (51.4% to 48.6%) in the control was significantly different from the X, Y group (P < 0.05). However, male and female puppies in the control had similar birth weights and weaning weights to those from the X and Y groups. This preliminary information indicated that normal puppies of predicted sex can be produced with low numbers of sorted cryopreserved dog spermatozoa at a farm level, making sperm-sexing technology potentially applicable for elite breeding units.


Subject(s)
Cryopreservation , Fertility , Freezing , Insemination, Artificial , Parturition , Pregnancy, Animal , Semen Preservation , Sex Preselection/methods , Sex Ratio , Spermatozoa , Animals , Dogs , Female , Male , Pregnancy
7.
Chemosphere ; 172: 488-495, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28092769

ABSTRACT

Phosphorous (P) concentration in stormwater runoff varies at different spatial and temporal scales. Excessive P loading from agriculture system into the St. Lucie Estuary (SLE) contributed to water quality deterioration in southern Indian River Lagoon. This study examines the spatial and temporal shifts of different P forms in runoff and storm water under different land use, water management, and rainfall conditions. Storm water samplings were conducted monthly between April 2013 and December 2014 in typical farmland and along the waterway (Canal C-24) that connects lands to the SLE. Concentrations of different P forms and related water quality variables were measured. Approximately 89% of the collected water samples contained total P (TP) concentrations exceeding the total maximum daily load (TMDL) level (0.081 mg L-1). Concentrations of different P forms declined from agricultural field furrows to the canal and then increased from the upstream to the downstream in the canal where urban activities dominated land use. Total dissolved P (TDP) was the predominant form of TP, followed by PO4-P. Speciation and concentrations of P varied with sites and sampling times, but were significantly higher in the summer months (from June to September) than in the winter. Water pH explained ∼20% of TP variation. Spatiotemporal variations of P concentrations and compositions provide a data-based guide for development of best management practices (BMPs) to minimize P export from the SLE watershed.


Subject(s)
Environmental Monitoring/methods , Estuaries , Phosphates/analysis , Phosphorus/analysis , Water Pollutants, Chemical/analysis , Agriculture , Electric Conductivity , Florida , Geography , Hydrogen-Ion Concentration , Rivers/chemistry , Seasons , Spatio-Temporal Analysis , Temperature , Water Purification/methods , Water Quality
8.
Environ Sci Pollut Res Int ; 23(19): 19561-9, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27392622

ABSTRACT

Nitrogen (N) is considered as a key element that triggers algal boom in the Indian River Lagoon (IRL), South Florida. Intensive agriculture may have contributed to increased N input into the IRL. Runoff and storm water samples were collected in representative agricultural fields and along waterways that connect lands to the IRL from April 2013 to December 2014. Concentrations of different N species (particulate N, dissolved organic N, dissolved NH4 (+)-N, and NO3 (-)-N) and related water physical-chemical properties were measured. Total N (TN) concentrations generally decreased from agricultural field furrows to discharging point of the waterways but were generally above the US EPA critical level (0.59 mg L(-1)) for surface water. Organic N was the dominant form of dissolved N, followed by NO3 (-)-N, and dissolved NH4 (+)-N. Concentrations and speciation of N in water varied with sites and sampling times but were generally higher in summer and fall and lower in spring and winter, as affected by the seasonality of regional hydrology and agricultural practices. Correlations occurred between N concentration, water physical properties, and rainfall. This information has important implications in the development of best management practices to minimize the impacts of agricultural practice on N loading in the Indian River Lagoon.


Subject(s)
Environmental Monitoring , Nitrogen/chemistry , Rivers/chemistry , Water Movements , Water Pollutants, Chemical/chemistry , Agriculture , Florida , Phosphorus/chemistry , Seasons
9.
PLoS One ; 11(3): e0150898, 2016.
Article in English | MEDLINE | ID: mdl-26964101

ABSTRACT

Forest soils play a critical role in the sequestration of atmospheric CO2 and subsequent attenuation of global warming. The nature and properties of organic matter in soils have an influence on the sequestration of carbon. In this study, soils were collected from representative forestlands, including a subtropical evergreen broad-leaved forest (EBF), a coniferous forest (CF), a subalpine dwarf forest (DF), and alpine meadow (AM) along an elevation gradient on Wuyi Mountain, which is located in a subtropical area of southeastern China. These soil samples were analyzed in the laboratory to examine the distribution and speciation of organic carbon (OC) within different size fractions of water-stable soil aggregates, and subsequently to determine effects on carbon sequestration. Soil aggregation rate increased with increasing elevation. Soil aggregation rate, rather than soil temperature, moisture or clay content, showed the strongest correlation with OC in bulk soil, indicating soil structure was the critical factor in carbon sequestration of Wuyi Mountain. The content of coarse particulate organic matter fraction, rather than the silt and clay particles, represented OC stock in bulk soil and different soil aggregate fractions. With increasing soil aggregation rate, more carbon was accumulated within the macroaggregates, particularly within the coarse particulate organic matter fraction (250-2000 µm), rather than within the microaggregates (53-250µm) or silt and clay particles (< 53µm). In consideration of the high instability of macroaggregates and the liability of SOC within them, further research is needed to verify whether highly-aggregated soils at higher altitudes are more likely to lose SOC under warmer conditions.


Subject(s)
Carbon/chemistry , Forests , Grassland , Soil/chemistry , China
10.
PLoS One ; 8(11): e78973, 2013.
Article in English | MEDLINE | ID: mdl-24265737

ABSTRACT

Stream water dissolved organic carbon (DOC) correlates positively with soil organic carbon (SOC) in many biomes. Does this relationship hold in a small geographic region when variations of temperature, precipitation and vegetation are driven by a significant altitudinal gradient? We examined the spatial connectivity between concentrations of DOC in headwater stream and contents of riparian SOC and water-soluble soil organic carbon (WSOC), riparian soil C:N ratio, and temperature in four vegetation types along an altitudinal gradient in the Wuyi Mountains, China. Our analyses showed that annual mean concentrations of headwater stream DOC were lower in alpine meadow (AM) than in subtropical evergreen broadleaf forest (EBF), coniferous forest (CF), and subalpine dwarf forest (SDF). Headwater stream DOC concentrations were negatively correlated with riparian SOC as well as WSOC contents, and were unrelated to riparian soil C:N ratio. Our findings suggest that DOC concentrations in headwater streams are affected by different factors at regional and local scales. The dilution effect of higher precipitation and adsorption of soil DOC to higher soil clay plus silt content at higher elevation may play an important role in causing lower DOC concentrations in AM stream of the Wuyi Mountains. Our results suggest that upscaling and downscaling of the drivers of DOC export from forested watersheds when exploring the response of carbon flux to climatic change or other drivers must done with caution.


Subject(s)
Carbon/analysis , Carbon/chemistry , Organic Chemicals/analysis , Organic Chemicals/chemistry , Rivers/chemistry , Soil/chemistry , Water/chemistry , China , Plant Development , Rain , Temperature
11.
Ying Yong Sheng Tai Xue Bao ; 24(12): 3446-52, 2013 Dec.
Article in Chinese | MEDLINE | ID: mdl-24697063

ABSTRACT

Based on the remote images in 2001 and 2010, the source and sink areas of urban heat island (UHI) in Shenyang City, Northeast China were determined by GIS technique. The effect of urban regional landscape pattern on UHI effect was assessed with land surface temperature (LST), area rate index (CI) of the source and sink areas and intensity index (LI) of heat island. The results indicated that the land use type changed significantly from 2001 to 2010, which significantly changed the source and sink areas of UHI, especially in the second and third circle regions. The source and sink areas were 94.3% and 5.7% in the first circle region, 64.0% and 36.0% in the third circle region in 2001, while they were 93.4% and 6.6%, 70.2% and 29.8% in 2010, respectively. It suggested that the land use pattern extended by a round shape in Shenyang led to the corresponding UHI pattern. The LST in the study area tended to decrease from the first circle region to the third. The UHI intensity was characterized with a single center in 2001 and with several centers in 2010, and the grade of UHI intensity was in a decreasing trend from 2001 to 2010. The absolute value of CI increased from the first circle region to the third, and the L1 was close to 1, suggesting the change in land use pattern had no significant influence on UHI in Shenyang.


Subject(s)
Cities , Hot Temperature , China , Environmental Monitoring
12.
Ying Yong Sheng Tai Xue Bao ; 23(5): 1345-50, 2012 May.
Article in Chinese | MEDLINE | ID: mdl-22919847

ABSTRACT

According to the recorded air temperature data and their continuity of each weather station, the location of each weather station, the numbers of and the distances among the weather stations, and the records on the weather stations migration, several weather stations in Liaoning Province were selected as the urban and rural representative stations to study the characteristics of urban heat island (UHI) intensity in the province. Based on the annual and monthly air temperature data of the representative stations, the ranges and amplitudes of the UHI intensity were analyzed, and the grades of the UHI intensity were classified. The Tieling station, Dalian station, Anshan station, Chaoyang station, Dandong station, and Jinzhou station and the 18 stations including Tai' an station were selected as the representative urban and rural weather stations, respectively. In 1980-2009, the changes of the annual UHI intensity in the 6 representative cities differed. The annual UHI intensity in Tieling was in a decreasing trend, while that in the other five cities was in an increasing trend. The UHI intensity was strong in Tieling but weak in Dalian. The changes of the monthly UHI intensity in the 6 representative cities also differed. The distribution of the monthly UHI intensity in Dandong, Jinzhou and Tieling took a "U" shape, with the maximum and minimum appeared in January and in May-August, respectively, indicating that the monthly UHI intensity was strong in winter and weak in summer. The ranges of the annual and monthly UHI intensity in the 6 cities were 0.57-2.15 degrees C and -0.70-4.60 degrees C, and the ranges of 0.5-2.0 degrees C accounted for 97.8% and 72.3%, respectively. The UHI intensity in the province could be classified into 4 grades, i. e., weak, strong, stronger and strongest.


Subject(s)
Cities , Environmental Monitoring/methods , Global Warming/statistics & numerical data , Hot Temperature , Meteorological Concepts , China , Seasons , Weather
13.
Ying Yong Sheng Tai Xue Bao ; 21(6): 1609-13, 2010 Jun.
Article in Chinese | MEDLINE | ID: mdl-20873642

ABSTRACT

The monthly, annual, and inter-decade variations of heat island effect in inner and outer suburbs of Shenyang and their relationships with urbanization were analyzed, based on the air temperature data from 1961 to 2008. It was indicated that the monthly and annual heat island effect was higher in inner suburb than in outer suburb, and decreased from inner suburb to outer suburb. The variation trend of monthly heat island effect in inner and outer suburbs was similar from March to November, but in contrary from December to next February, possibly due to the effects of heating in winter. The annual heat island effect in both inner and outer suburbs had an increasing trend before 2000 but a decreasing trend after 2000, and was significantly positively correlated with the green land area, population, and established construction area before 2000 (P < 0.05), but significantly negatively correlated with them after 2000 (P < 0.05), the correlation degree being 0.43, 0.52, and 0.26, respectively.


Subject(s)
Ecosystem , Global Warming/statistics & numerical data , Hot Temperature , Suburban Health , Urbanization/trends , China , Environmental Monitoring/methods , Seasons
14.
Biotechnol Adv ; 27(5): 616-24, 2009.
Article in English | MEDLINE | ID: mdl-19409479

ABSTRACT

We studied the spray characteristics of inedible oil using experimental and simulation methods. Spray penetration, spray cone angle and spray tip speed were measured at different biodiesel ratios in a constant volume vessel with wide visualization and high back pressure, using a high-speed camera. The characteristics of biodiesel spray were simulated under the same conditions using Star-CD software. The experimental results showed that, as the ratio of biodiesel in the blends increased, spray penetration and spray speed increased, but the spray cone angle decreased. Throughout the spray injection period, the region at 0.05-0.475S (spray tip penetration) was a key area affecting spray cone angle. From 0.8 ms after injection, the spray penetration deviation ratios started to increase with increasing biodiesel blend ratios. Simulation results showed similar macroscopic spray characteristics to the experimental results for jatropha oil. The results also showed that the Sauter mean diameter of blend fuels was greater than that of diesel, and spray was more concentrated, due to the higher viscosity and surface tension of the biodiesel, compared with conventional diesel fuel. The macroscopic and microscopic spray properties of blended fuels containing 5%, 10% and 20% biodiesel were similar to diesel.


Subject(s)
Energy-Generating Resources , Gasoline , Plant Oils/chemistry , Aerosols , Computer Simulation , Equipment Design , Jatropha , Pressure , Software
15.
Ying Yong Sheng Tai Xue Bao ; 18(10): 2202-8, 2007 Oct.
Article in Chinese | MEDLINE | ID: mdl-18163298

ABSTRACT

By using GIS and RS techniques, the edge effects of forest landscape in the upper reaches of Minjiang River, Sichuan Province of China were studied on landscape scale. The results showed that there was a distinct boundary between forestland and farmland, with the vegetation changed significantly. The biomass at forestland edge was lower than that in forestland interior, with the edge effect width being 60 m, whereas the biomass in farmland exterior was higher than that in farmland interior, with the edge effect width being 60-90 m. Forestland-grassland boundary was naturally formed and changed gradually. The biomass at forestland edge was lower than that in forestland interior, while that at grassland edge was higher than that in grassland interior, with the edge effect being 60 m for forestland and 45-75 m for grassland. The edge effect of forestland-shrub land boundary was similar to that of forestland-grassland boundary, with the edge effect width being 60 m for forestland and 45-75 m for shrub land.


Subject(s)
Biomass , Ecosystem , Trees/growth & development , China , Conservation of Natural Resources , Environment Design , Geographic Information Systems , Poaceae/growth & development , Rivers , Satellite Communications
16.
Ying Yong Sheng Tai Xue Bao ; 17(5): 935-8, 2006 May.
Article in Chinese | MEDLINE | ID: mdl-16883831

ABSTRACT

Depth of edge influence of landscape boundary is an important component of landscape boundary research, and also, the hotspot of ecological research at home and abroad. This paper summarized the recent decades' research advances abroad in depth of edge influence, including quantitative methods, depth of edge influence on abiotic and biotic factors, and affecting factors on depth of edge influence. The studies on depth of edge influence in our country were also discussed,with the development trend prospected.


Subject(s)
Conservation of Natural Resources , Ecology/trends , Ecosystem , Trees/growth & development , Environment
17.
Int J Food Microbiol ; 106(1): 74-8, 2006 Jan 15.
Article in English | MEDLINE | ID: mdl-16300850

ABSTRACT

Of 45 Escherichia coli O157 isolates from cattle feces, which were collected between May 2000 and September 2003 in Korea, 32 were resistant to at least 1 antibiotic and 28 were resistant to 4 or more antibiotics, with 32, 30 and 30 of the isolates being resistant to streptomycin, tetracycline and sulfisoxazole, respectively. Two isolates were resistant to fluoroquinolones and to 10 or more of the 22 other antimicrobial agents that were tested. Thirteen antimicrobial resistant patterns were observed. The most frequent resistance type, which was found for 11 isolates, was streptomycin-tetracycline-kanamycin-ampicillin-piperacillin-cephalothin-sulfisoxazole-ticarcillin. Polymerase chain reaction (PCR) analysis of the isolates for E. coli O157 virulence markers revealed that 25 of the resistant E. coli O157 isolates tested positive for stx2 or both stx1 and stx2 genes. These findings suggest that many of the resistant E. coli O157 isolates might cause disease in humans.


Subject(s)
Anti-Bacterial Agents/pharmacology , Escherichia coli O157/drug effects , Escherichia coli Proteins/analysis , Animals , Cattle , Cattle Diseases/microbiology , Colony Count, Microbial , Consumer Product Safety , Drug Resistance, Bacterial , Drug Resistance, Multiple, Bacterial , Escherichia coli Infections/microbiology , Escherichia coli Infections/veterinary , Escherichia coli O157/genetics , Escherichia coli O157/isolation & purification , Feces/microbiology , Food Microbiology , Humans , Meat/microbiology , Microbial Sensitivity Tests , Polymerase Chain Reaction/methods , Polymerase Chain Reaction/veterinary , Shiga Toxins/analysis , Shiga Toxins/genetics , Virulence Factors/genetics , Virulence Factors/isolation & purification
18.
Ying Yong Sheng Tai Xue Bao ; 17(11): 2011-5, 2006 Nov.
Article in Chinese | MEDLINE | ID: mdl-17269317

ABSTRACT

A typical pepper-forest boundary was selected in the arid valley of Minjiang River upper reaches, and the moisture content in 0-15 cm soil layer was determined by time-domain reflectometry (TDR) during drought, after rain, and different seasons. Moving split-window techniques (MSWT) was employed to detect the depth of edge influence (DEI) on soil moisture and its dynamic variation with time. The results showed that the changes of squared Euclidean distance (SED) curve on the graph tended to become stable when the window width reached 8 - 12, and DEI could be detected. The seasonal variation of soil moisture could be divided into three periods, i.e., rising period (January to April), peak period (May to October), and lessen period (November to December). DEI was smaller during drought, and increased after rain. The DEI on soil moisture ranged from 6 m in pepper field to 2 m in forest during drought and from 12 m in pepper field to 2 m in forest after rain, but ranged from 10 m in pepper field to 2 m in forest field within a year. DEI was different in different seasons, and was dynamic. Under such condition of soil moisture, the forest restoration from pepper land and the seedling planting were not ecologically reasonable. Reducing human disturbance and revegetating with natural shrubs and meadows could be more effective for vegetation conservation in the arid valley of Minjiang River upper reaches.


Subject(s)
Capsicum/growth & development , Environmental Monitoring , Soil/analysis , Trees/growth & development , Water/metabolism , Capsicum/metabolism , China , Rain , Rivers , Seasons
19.
Ying Yong Sheng Tai Xue Bao ; 15(10): 1804-8, 2004 Oct.
Article in Chinese | MEDLINE | ID: mdl-15624812

ABSTRACT

By using moving split-window techniques (MSWT), this study estimated how far the edge effects penetrated the forest and agricultural fields in the arid valley of upper reaches of Minjiang River, southwestern China. Its aim was to provide general information on vegetation along edge to interior gradients in order to assist in interpretation and prediction of biological phenomena associated with agriculture-forestry boundary, and to improve current management practices in such areas. Three types of boundaries (10 transects) were investigated and sampled. The results showed that when the window width reached 6-10, the change of the SED curve on the graph tended to become stable, and one or two peaks occurred. The depth of edge influence was clearly different for different types of boundaries, and could be estimated within 50 m from the edge to interior. The depth of edge influence (DEI) on vegetation diversity almost varied between 12-30 m, mainly depending on the patch type, topography and microclimate, but seldom on slope orientation. Of the 6 forest transects in the three types of boundaries, the DEI was detected only in the forest part transects M2 and M6, but almost detectable in the agricultural part of all transects. MSWT was considered to be a useful tool for characterizing edge dynamics if enough data was available, and became a simple and powerful technique for analyzing the boundary. The results will provide further knowledge for understanding the interaction between forestry and agriculture in the arid valley.


Subject(s)
Crops, Agricultural/growth & development , Ecosystem , Trees/growth & development , Water Supply , China , Environment , Rivers
20.
Ying Yong Sheng Tai Xue Bao ; 15(5): 891-4, 2004 May.
Article in Chinese | MEDLINE | ID: mdl-15320418

ABSTRACT

In this paper, the accumulation and translocation of lead in soil-crop ecosystems were studied through fertilization with chemical fertilizer, manure and bio-fertilizer. The results showed that the soil total Pb content was decreased with soil depth. It was 11.14 and 9.37 mg x kg(-1) in 0-15 and 15-30 cm after harvest, respectively. Rice root absorbed lead from soil, and transferred it to stem-leaf and grain. The Pb content in rice plant was root>stem and leaf>grain, which was increased with rice growth. The grains of 606-14 and Liao 294 contained 0. 008 and 0.007 mg x kg(-1) of Pb, respectively, which is under the standard of green food. Variance analysis indicated that the grain yield of different varieties had a significant variance, but no significant variance was found among different treatments. It could be summarized that manure or bio-fertilizer could be the substitute of chemical fertilizer in producing rice.


Subject(s)
Lead/analysis , Oryza/metabolism , Soil Pollutants/analysis , Soil/analysis , Absorption , Fertilizers , Oryza/chemistry , Plant Roots/chemistry , Plant Roots/metabolism
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