Fate and transport of faecal contamination microbial indicators, pathogenic protozoa and Campylobacter in the artificially recharged fractured aquifer of Salento, Italy

2008 ◽  
Vol 57 (6) ◽  
pp. 849-856 ◽  
Author(s):  
R. La Mantia ◽  
C. Masciopinto ◽  
C. Levantesi ◽  
V. Tandoi
Keyword(s):  
Pathogenic Bacteria ◽  
Fate And Transport ◽  
Fractured Aquifer ◽  
Specific Detection ◽  
Microbial Indicators ◽  
Faecal Contamination ◽  
Time Required ◽  
Indicators Of Faecal Contamination ◽  
Campylobacter Spp

The study investigates the fate and transport of microorganisms introduced by artificial groundwater recharge at the Nardò fractured aquifer in Salento, Italy. Microbial indicators of faecal contamination, parasitic protozoa (Giardia and Cryptosporidium) and pathogenic bacteria (Campylobacter spp.), were monitored into injected water and groundwater to test the efficiency of the “natural disinfection” into the fractured aquifer. A remarkable decrease of microbial indicators and pathogens was observed suggesting that pathogens removal or inactivation may be possible during water flow in fractured aquifer. The recently described PNA probe CJE195 (Lehtola et al. 2005) was utilised for the rapid and specific detection of Campylobacter spp. by fluorescence in situ hybridization (FISH) after enrichment. FISH results were consistent with those of traditional cultural method (ISO 17995) applied in parallel: time required for Campylobacter identification was reduced of 4 days.

scholarly journals Influence of the method of whole wheat inclusion on performance and caecal microbiota profile of broiler chickens

2019 ◽  
Vol 7 ◽  
Author(s):  
Yashpal Singh ◽  
Abdul Latiff Molan ◽  
Velmurugu Ravindran
Keyword(s):  
Broiler Chickens ◽  
Pathogenic Bacteria ◽  
Gas Production ◽  
Whole Wheat ◽  
Hybridisation Analysis ◽  
Ad Libitum ◽  
Ground Wheat ◽  
Caecal Microbiota ◽  
Campylobacter Spp

SummaryA study was conducted to investigate the effect of method of whole wheat inclusion on performance and caecal microbiota profile of broiler chickens. Fluorescencein situhybridisation analysis was used to characterise the microbiota by using genus-specific probes. Three treatments, namely, ground wheat (GW) or 200 g/kg whole wheat (WW) replacing GW before or after pelleting were evaluated. A total of 144, one-day-old male broilers (Ross 308) were allocated to 18 cages (eight broilers per cage) based on body weight and six cages were randomly assigned to each treatment. The diets were offeredad libitumfrom day 11 to 35 post-hatch. The WW fed birds, regardless of the method of inclusion, resulted in poorer weight gain (P < 0.05) and reduced feed intake (P < 0.001), but a similar feed per gain (P > 0.05) compared to those fed the GW diet. The WW diet, regardless to the method of inclusion, had no effect (P > 0.05) on the populations ofLactobacillusandBacteroides spp.compared with the GW diet. TheBifidobacterium spp.population was higher (P < 0.05) in birds fed the GW diet compared with WW feeding, regardless of the method of inclusion. A reduction (P < 0.05) in the numbers of pathogenicClostridiumandCampylobacter spp.were observed in caecal samples from birds fed WW diets, regardless of method of inclusion, compared with those fed the GW diet, which was attributed to increased gizzard activity. Birds fed WW diets, regardless to the method of inclusion, showed a reduction in gizzard pH (P < 0.05), microbial gas production (P < 0.05), and an increase in gizzard weight (P < 0.05) relative to the GW treatment. The results indicated that the gizzard has an important function as a barrier organ, one that prevents pathogenic bacteria from entering the distal digestive tract.

scholarly journals Microbial indicators of faecal contamination in waters and sediments of beach bathing zones

2008 ◽  
Vol 211 (5-6) ◽  
pp. 510-517 ◽  
Author(s):  
M.C. Garrido-Pérez ◽  
E. Anfuso ◽  
A. Acevedo ◽  
J.A. Perales-Vargas-Machuca
Keyword(s):  
Microbial Indicators ◽  
Faecal Contamination ◽  
Indicators Of Faecal Contamination

Microbial Indicators of Faecal Contamination in Water: A Current Perspective

2005 ◽  
Vol 166 (1-4) ◽  
pp. 139-166 ◽  
Author(s):  
Pam Tallon ◽  
Brenda Magajna ◽  
Cassandra Lofranco ◽  
Kam Tin Leung
Keyword(s):  
Microbial Indicators ◽  
Faecal Contamination ◽  
Current Perspective ◽  
Indicators Of Faecal Contamination ◽  
A Current

Coliform transport in a pristine reservoir: modeling and field studies

1998 ◽  
Vol 37 (2) ◽  
pp. 137-144 ◽  
Author(s):  
Elisa Garvey ◽  
John E. Tobiason ◽  
Michael Hayes ◽  
Evelyn Wolfram ◽  
David A. Reckhow ◽  
...  
Keyword(s):  
Model Development ◽  
Fate And Transport ◽  
Field Studies ◽  
Meteorological Conditions ◽  
Reservoir Modeling ◽  
Vertical Circulation ◽  
Quality Model ◽  
Circulation Patterns ◽  
In Situ Experiments

This paper reports on field studies and model development aimed at understanding coliform fate and transport in the Quabbin Reservoir, an oligotrophic drinking water supply reservoir. An investigation of reservoir currents suggested the importance of wind driven phenomena, and that both lateral and vertical circulation patterns exist. In-situ experiments of coliform decay suggested dependence on light intensity and yielded an appropriate decay coefficient to be used in CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model. Modeling confirmed the sensitivity of reservoir outlet concentration to vertical variability within the reservoir, meteorological conditions, and location of coliform source.

scholarly journals In-situ tryptophan-like fluorescence: A real-time indicator of faecal contamination in drinking water supplies

2015 ◽  
Vol 81 ◽  
pp. 38-46 ◽  
Author(s):  
J.P.R. Sorensen ◽  
D.J. Lapworth ◽  
B.P. Marchant ◽  
D.C.W. Nkhuwa ◽  
S. Pedley ◽  
...  
Keyword(s):  
Drinking Water ◽  
Real Time ◽  
Water Supplies ◽  
Faecal Contamination

In situ enzymatic removal of orthophosphate by the nucleoside phosphorylase catalyzed phosphorolysis of nicotinamide riboside

1982 ◽  
Vol 60 (9) ◽  
pp. 917-921 ◽  
Author(s):  
John W. Shriver ◽  
Brian D. Sykes
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nucleoside Phosphorylase ◽  
Nicotinamide Riboside ◽  
Time Required ◽  
Removal System ◽  
Nuclear Magnetic

An enzymatic orthophosphate removal system is described which can be effectively used to continuously remove orthophosphate from biochemical samples. The phosphorolysis of nicotinamide riboside is catalyzed by calf spleen nucleoside phosphorylase to give ribose-1-PO4 and nicotinamide along with a proton. At pH 8 the production of ribose-1-PO4 from orthophosphate is essentially quantitative. This reaction can be monitored optically or by 31P nuclear magnetic resonance (NMR). Equations are given for determining the time required to remove a given amount of phosphate from a typical NMR sample with a known amount of nucleoside phosphorylase. The effects of a competing orthophosphate-producing reaction are considered.

In-Situ, Time Resolved, Kinetics of Reactions in Co-Ge thin Films

1991 ◽  
Vol 237 ◽  
Author(s):  
R. M. Walser ◽  
Byung-Hak Lee ◽  
Alaka Valanju ◽  
Winston Win ◽  
M. F. Becker
Keyword(s):  
Depth Profiling ◽  
Laser Interferometry ◽  
Semiconductor Interface ◽  
Time Resolved ◽  
Interface Reactions ◽  
Valuable Adjunct ◽  
Diffusion Controlled ◽  
Sputter Deposited ◽  
Time Required

ABSTRACTWe report the first kinetic study of metal-semiconductor interface reactions using in-situ, time resolved, laser interferometry. Diffusion couples with Co/Ge thicknesses of 1500 Å/1500 Å were sputter deposited on silicon wafers, and vacuum-annealed at temperatures between 300°C-400°C. Under these conditions polycrystalline CoGe was expected to form [1]. Real time laser (HeNe 6328 Å) interferograms for each anneal were recorded in-situ. These data were supplemented by information from AES and X-ray.For temperatures below 400°C the diffusion controlled formation of CoGe was observed. The composition was confirmed by Auger depth profiling that showed uniform Co and Ge concentrations when the reaction went to completion. The well defined interferences fringes were formed by the dissolution of amorphous Ge. The activation energy = 1.6 eV for the formation of CoGe were determined with precision from the temperature dependence of the time required to anneal the fixed λ/4 distance between adjacent minima and maxima of the interferogram. We discuss the evidence for formation of an intermediate Co-rich compound following the initial diffusion of Co into Ge. The results of these experiments indicate that optical interferometry will be a valuable adjunct to other techniques used to study metal-semiconductor interface reactions.

The importance of the turbulent ship wake regime for pollutant fate and transport

2021 ◽  
Author(s):  
Amanda T. Nylund ◽  
Rickard Bensow ◽  
Mattias Liefvendahl ◽  
Arash Eslamdoost ◽  
Anders Tengberg ◽  
...  
Keyword(s):  
Fate And Transport ◽  
In Situ Measurements ◽  
Ex Situ ◽  
Landsat 8 ◽  
Turbulent Regime ◽  
Near Wake ◽  
Ship Wake ◽  
Spatiotemporal Scales ◽  
The Impact

&lt;p&gt;This interdisciplinary study with implications for fate and transport of pollutants from shipping, investigates the previously overlooked phenomenon of ship induced mixing. When a ship moves through water, the hull and propeller induce a long-lasting turbulent wake. Natural waters are usually stratified, and the stratification influences both the vertical and horizontal extent of the wake. The altered turbulent regime in shipping lanes governs the distribution of discharged pollutants, e.g. PAHs, metals, nutrients and non-indigenous species. The ship related pollutant load follows the trend in volumes of maritime trade, which has almost tripled since the 1980s. In heavily trafficked areas there may be one ship passage every ten minutes; today shipping constitutes a significant source of pollution.&lt;/p&gt;&lt;p&gt;To understand the environmental impact of shipping related pollutants, it is essential to know their fate following regional scale transport. However, previous modelling efforts assuming discharge at the surface will not adequately reflect the input values in the regional models. Therefore, it is urgent to bridge the gaps between the spatiotemporal scales from high-resolution numerical modeling of the flow hydrodynamics around the ship, mixing processes and interaction of the ship and wake with stratification, and parameterization in regional oceanographic modeling. Here this knowledge gap is addressed by combining an array of methods; in situ measurements, remote sensing and numerical flow modeling.&lt;/p&gt;&lt;p&gt;A bottom-mounted Acoustic Doppler Current Profiler was placed under a ship lane, for &lt;em&gt;in-situ&lt;/em&gt; measurements of the vertical and temporal expansion of turbulent wakes. In addition, &lt;em&gt;ex-situ&lt;/em&gt; measurements with Landsat 8 Thermal Infrared Sensor were used to estimate the longevity and spatial extent of the thermal signal from ship wakes. The computational modelling was conducted using well resolved 3D RANS modelling for the hull and the near wake (up to five ship lengths aft), a method typically used for the near wake behaviour in analysing the propulsion system. As this is not feasible to use for a far wake analysis, the predicted wake is then used as input for a 2D+time modelling for the sustained wake up to 30min after the ship passage. These results, both from measurements and numerical models, are then combined to analyse how ship-induced turbulence influence at what depth discharged pollutants will be found.&lt;/p&gt;&lt;p&gt;This first step to cover the mesoscales of the turbulent ship wake is necessary to assess the impact of ship related pollution. In-situ measurements show median wake depth 13.5m (max 31.5m) and median longevity 10min (max 29min). Satellite data show median thermal wake signal 13.7km (max 62.5km). A detailed simulation model will only be possible to use for the first few 100m of the ship wake, but the coupling to a simplified 2D+time modelling shows a promising potential to bridge our understanding of the impact of the ship wake on the larger scales. Our model results indicate that the natural stratification affects the distribution and retention of pollutants in the wake region. The depth of discharge and the wake turbulence characteristics will in turn affect the fate and transport of pollutants on larger spatiotemporal scales.&lt;/p&gt;

EFFECTS OF GROWING SEASON SOIL TEMPERATURE, MOISTURE, AND NH4-N ON SOIL NITROGEN

1974 ◽  
Vol 54 (4) ◽  
pp. 403-412 ◽  
Author(s):  
C. A. CAMPBELL ◽  
D. W. STEWART ◽  
W. NICHOLAICHUK ◽  
V. O. BIEDERBECK
Keyword(s):  
Quantitative Relationship ◽  
Growing Season ◽  
Stepwise Multiple Regression ◽  
Soil N ◽  
N Transformations ◽  
Temperature Changes ◽  
Diurnal Patterns ◽  
Multiple Regression Technique ◽  
Time Required

Wood Mountain loam was wetted with water or (NH4)2SO4 solution to provide a factorial combination among three moisture and three NH4-N levels. Samples in polyethylene bags were incubated at 2.5-cm depths in fallow, and in an incubator that simulated the diurnal patterns of temperature fluctuation recorded in the field. During the growing season, treatments were sampled regularly for moisture, NO3− and exchangeable NH4-N. Similar determinations were made on in situ samples taken in fallow Wood Mountain loam. The incubator simulated the effects of growing season temperatures on soil N transformations satisfactorily. Pronounced increases or decreases in temperature led to flushes in N mineralization. However, in the 1972 growing season, temperature was suboptimal and temperature changes were generally small. Consequently, when a stepwise multiple regression technique was used to analyze the data, neither ammonification nor nitrification showed a quantitative relationship to temperature. Comparison of the nitrification occurring in laboratory-incubated soils with that occurring in situ led to the conclusion that 70 to 90% of the NO3-N produced in surface soil resulted from wetting and drying. Estimates of potentially ammonifiable soil N(No) and its rate of mineralization (k) were derived from cumulative ammonification by assuming that the laws of first-order kinetics were applicable. In the 10, 15, and 20% moisture treatments the average No was 27, 41, and 82 ppm, respectively. Under the conditions of this study, the time required to mineralize half of No was about 7 wk.

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