scholarly journals Evaluation of Stormwater Biofilter Media for Escherichia coli Removal in a Laboratory Microcosm

2008 ◽  
Vol 1 ◽  
pp. ASWR.S825
Author(s):  
Gregory T. Kleinheinz ◽  
Tabitha Zehms ◽  
Kathryn Koenig
Keyword(s):  
Escherichia Coli ◽  
Free Water ◽  
Storm Water ◽  
Management Tool ◽  
Rain Event ◽  
Laboratory System ◽  
Recreational Water ◽  
Indicator Organism ◽  
Great Lakes Basin ◽  
The Impact

Recreational water sites such as beaches along lakes, rivers, or oceans, are one of the most popular activities in many parts of the world. Recently rainfall and runoff due to rainfall events has been associated with increasing microbial levels in recreational water. This runoff can lead to beach closures and potentially unsanitary conditions at popular swimming beaches. The impact of stormwater on beach water quality has led to a myriad of option for controlling stormwater. Some of these include grass buffer partitions, stormwater detention basins, media filters, catch basin inserts, and infiltration units. Biofilters, or infiltration units are gaining popularity as a treatment option for stormwater around the Great Lakes basin, but we are aware of no studies that have looked at the indicator organism (i.e. Escherichia coli, or E.coli) removal potential of these infiltration units and the media used in them. The overall objective of this study was to evaluate the performance of a stormwater biofilter medium in removing the indicator organism E.coli in a laboratory system. When several laboratory biofilter system were challenged with E.coli concentrations of 2.82E3 and 2.85E5 E.coli/100mL of simulated stormwater in a 1.25 cm rain event, the systems were able to remove between 83 and 100% of the E.coli in this influent. During a subsequent 1.25 cm rain event with E.coli-free water, the biofilter was able to retain 68%-100% of the E.coli originally inoculated into the system. The results of this study indicate that these systems hold promise for mitigation of E.coli from storm water near recreational beaches. These findings will assist beach managers, engineers, and municipal stake holders evaluate the usefulness of biofilter infiltration as a storm water management tool in order to decrease E.coli input into beach areas.

Online Modeling of CO2 Storage Systems

2021 ◽  
Author(s):  
Dale Douglas Erickson ◽  
Greg Metcalf
Keyword(s):  
Co2 Storage ◽  
Free Water ◽  
Oil Field ◽  
Management Tool ◽  
Carbon Dioxide Injection ◽  
Injection Wells ◽  
Internal Corrosion ◽  
Injection Process ◽  
Corrosion Risk ◽  
The Impact

Abstract This paper discusses the development and deployment of a specialized online and offline integrated model to simulate the CO2 (Carbon Dioxide) Injection process. There is a very high level of CO2 in an LNG development and the CO2 must be removed in order to prepare the gas to be processed into LNG. To mitigate the global warming effects of this CO2, a large portion of the CO2 Rich Stream (98% purity) is injected back into a depleted oil field. To reduce costs, carbon steel flowlines are used but this introduces a risk of internal corrosion. The presence of free water increases the internal corrosion risk, and for this reason, a predictive model discussed in this paper is designed to help operations prevent free water dropout in the network in real time. A flow management tool (FMT) is used to monitor the current state of the system and helps look at the impact of future events (startup, shutdowns etc.). The tool models the flow of the CO2 rich stream from the outlet of the compressor trains, through the network pipeline and manifolds and then into the injection wells. System behavior during steady state and transient operation is captured and analyzed to check water content and the balance of trace chemicals along with temperature and pressure throughout the network helping operators estimate corrosion rates and monitor the overall integrity of the system. The system has been running online for 24/7 for 2 years. The model has been able to match events like startup/shutdown, cooldowns and blowdowns. During these events the prediction of temperature/pressure at several locations in the field matches measured data. The model is then able to forecasts events into the future to help operations plan how they will operate the field. The tool uses a specialized thermodynamic model to predict the dropout of water in the near critical region of CO2 mixtures which includes various impurities. The model is designed to model startup and shutdown as the CO2 mixture moves across the phase boundary from liquid to gas or gas to liquid during these operations.

Balanced Scorecard in the strategic planning of a construction company

2018 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Roberth Frias ◽  
Maria Medina
Keyword(s):  
Strategic Planning ◽  
Strategic Management ◽  
Balanced Scorecard ◽  
Organization Theory ◽  
Management Control ◽  
Management Tool ◽  
The Balanced Scorecard ◽  
Construction Company ◽  
Construction Companies ◽  
The Impact

This research focused on the strategic management tool Balanced Scorecard and strategic planning, as a guide to guide the management of companies, allowing communication and the functionality of the strategy using KPIs that allow to identify, maintain control and increase efficiency and the achievement of optimal results. For the deductive hypothetical analysis, the specific factors that affect business management performance were grouped into two variables: Balanced Scorecard and Strategic Planning. The objective of the work was to demonstrate the impact of the Balanced Scorecard in the strategic planning of a construction company. In order to support the research, the following theories were approached: the Financial Theory, the Economic Theory of the Company, the Transaction Costs, the Network Theory, the Organization Theory, the Dependence on Resources, the Strategic Management Theory and the Business Diagnosis Theory. The result obtained confirms the hypothesis that there is a significant incidence of the Balanced Scorecard in the strategic planning of construction companies. In conclusion, the construction company has obtained significant improvements in the results in each of the indicators evaluated with the implementation of the Balanced Scorecard, demonstrating improvements in their management results, affirming that there is better performance and management control allowing them to achieve the organizational objectives set.

scholarly journals The Protein Interactome of Glycolysis in Escherichia coli

Proteomes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 16
Author(s):  
Shomeek Chowdhury ◽  
Stephen Hepper ◽  
Mudassir K. Lodi ◽  
Milton H. Saier ◽  
Peter Uetz
Keyword(s):  
Escherichia Coli ◽  
Protein Interactions ◽  
Allosteric Regulation ◽  
Glycolytic Enzymes ◽  
Protein Protein Interactions ◽  
Post Translational Modification ◽  
Interacting Protein ◽  
E Coli ◽  
Protein Interactome ◽  
The Impact

Glycolysis is regulated by numerous mechanisms including allosteric regulation, post-translational modification or protein-protein interactions (PPI). While glycolytic enzymes have been found to interact with hundreds of proteins, the impact of only some of these PPIs on glycolysis is well understood. Here we investigate which of these interactions may affect glycolysis in E. coli and possibly across numerous other bacteria, based on the stoichiometry of interacting protein pairs (from proteomic studies) and their conservation across bacteria. We present a list of 339 protein-protein interactions involving glycolytic enzymes but predict that ~70% of glycolytic interactors are not present in adequate amounts to have a significant impact on glycolysis. Finally, we identify a conserved but uncharacterized subset of interactions that are likely to affect glycolysis and deserve further study.

scholarly journals Impact of On-Farm Interventions against CTX-Resistant Escherichia coli on the Contamination of Carcasses before and during an Experimental Slaughter

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 228
Author(s):  
Michaela Projahn ◽  
Jana Sachsenroeder ◽  
Guido Correia-Carreira ◽  
Evelyne Becker ◽  
Annett Martin ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Broiler Chickens ◽  
Stocking Density ◽  
Resistant Bacteria ◽  
Control Group ◽  
Cross Contamination ◽  
High Prevalence ◽  
On Farm ◽  
The Impact ◽  
Slow Growing

Cefotaxime (CTX)-resistant Enterobacteriaceae are still an ongoing challenge in human and veterinary health. High prevalence of these resistant bacteria is detected in broiler chickens and the prevention of their dissemination along the production pyramid is of major concern. The impact of certain on-farm interventions on the external bacterial contamination of broiler chickens, as well as their influence on single processing steps and (cross-) contamination, have not yet been evaluated. Therefore, we investigated breast skin swab samples of broiler chickens before and during slaughter at an experimental slaughter facility. Broiler chickens were previously challenged with CTX-resistant Escherichia coli strains in a seeder-bird model and subjected to none (control group (CG)) or four different on-farm interventions: drinking water supplementation based on organic acids (DW), slow growing breed Rowan × Ranger (RR), reduced stocking density (25 kg/sqm) and competitive exclusion with Enterobacteriales strain IHIT36098(CE). Chickens of RR, 25 kg/sqm, and CE showed significant reductions of the external contamination compared to CG. The evaluation of a visual scoring system indicated that wet and dirty broiler chickens are more likely a vehicle for the dissemination of CTX-resistant and total Enterobacteriaceae into the slaughterhouses and contribute to higher rates of (cross-) contamination during processing.

scholarly journals Solubility assessment of single-chain antibody fragment against epithelial cell adhesion molecule extracellular domain in four Escherichia coli strains

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Fatemeh Sadat Javadian ◽  
Majid Basafa ◽  
Aidin Behravan ◽  
Atieh Hashemi
Keyword(s):  
Escherichia Coli ◽  
Cell Adhesion ◽  
Epithelial Cell ◽  
Adhesion Molecule ◽  
Cell Adhesion Molecule ◽  
Extracellular Domain ◽  
Epithelial Cell Adhesion Molecule ◽  
Single Chain ◽  
E Coli ◽  
The Impact

Abstract Background Overexpression of the EpCAM (epithelial cell adhesion molecule) in malignancies makes it an attractive target for passive immunotherapy in a wide range of carcinomas. In comparison with full-length antibodies, due to the small size, the scFvs (single-chain variable fragments) are more suitable for recombinant expression in E. coli (Escherichia coli). However, the proteins expressed in large amounts in E. coli tend to form inclusion bodies that need to be refolded which may result in poor recovery of bioactive proteins. Various engineered strains were shown to be able to alleviate the insolubility problem. Here, we studied the impact of four E. coli strains on the soluble level of anti-EpEX-scFv (anti-EpCAM extracellular domain-scFv) protein. Results Although results showed that the amount of soluble anti-EpEX-scFv obtained in BL21TM (DE3) (114.22 ± 3.47 mg/L) was significantly higher to those produced in the same condition in E. coli RosettaTM (DE3) (71.39 ± 0.31 mg/L), and OrigamiTM T7 (58.99 ± 0.44 mg/L) strains, it was not significantly different from that produced by E. coli SHuffleTM T7 (108.87 ± 2.71 mg/L). Furthermore, the highest volumetric productivity of protein reached 318.29 ± 26.38 mg/L in BL21TM (DE3). Conclusions Although BL21TM (DE3) can be a suitable strain for high-level production of anti-EpEX-scFv protein, due to higher solubility yield (about 55%), E. coli SHuffleTM T7 seems to be better candidate for soluble production of scfv compared to BL21TM (DE3) (solubility yield of about 30%).

scholarly journals The gut at war: the consequences of enteropathogenic Escherichia coli infection as a factor of diarrhea and malnutrition

2000 ◽  
Vol 118 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Ulysses Fagundes-Neto ◽  
Isabel Cristina Affonso Scaletsky
Keyword(s):  
Escherichia Coli ◽  
Diarrheal Disease ◽  
Driving Forces ◽  
Public Health Problem ◽  
Clinical Aspects ◽  
Small Intestinal Mucosa ◽  
Enteropathogenic Escherichia Coli ◽  
Important Public Health Problem ◽  
The Impact

Diarrheal disease is still the most prevalent and important public health problem in developing countries, despite advances in knowledge, understanding, and management that have occurred over recent years. Diarrhea is the leading cause of death in children under 5 years of age. The impact of diarrheal diseases is more severe in the earliest periods of life, when taking into account both the numbers of episodes per year and hospital admission rates. This narrative review focuses on one of the major driving forces that attack the host, namely the enteropathogenic Escherichia coli (EPEC) and the consequences that generate malnutrition in an early phase of life. EPEC serotypes form dense microcolonies on the surface of tissue-culture cells in a pattern known as localized adherence (LA). When EPEC strains adhere to epithelial cells in vitro or in vivo they cause characteristic changes known as Attaching and Effacement (A/E) lesions. Surface abnormalities of the small intestinal mucosa shown by scanning electron microscopy in infants with persistent diarrhea, although non-specific, are intense enough to justify the severity of the clinical aspects displayed in a very young phase in life. Decrease in number and height of microvilli, blunting of borders of enterocytes, loss of the glycocalyx, shortening of villi and presence of a mucus pseudomembrane coating the mucosal surface were the abnormalities observed in the majority of patients. These ultrastructural derangements may be due to an association of the enteric enteropathogenic agent that triggers the diarrheic process and the onset of food intolerance responsible for perpetuation of diarrhea. An aggressive therapeutic approach based on appropriate nutritional support, especially the utilization of human milk and/or lactose-free protein hydrolyzate-based formulas and the adequate correction of the fecal losses, is required to allow complete recovery from the damage caused by this devastating enteropathogenic agent.

scholarly journals A Review of Nontraditional Biomanipulation

2008 ◽  
Vol 8 ◽  
pp. 1184-1196 ◽  
Author(s):  
Xia Zhang ◽  
Ping Xie ◽  
Xiaoping Huang
Keyword(s):  
Algal Blooms ◽  
Algal Species ◽  
Planktivorous Fish ◽  
Bighead Carp ◽  
Cyanobacterial Blooms ◽  
Management Tool ◽  
Nutrient Concentrations ◽  
Effective Management ◽  
Nuisance Algae ◽  
The Impact

The aim of this review is to identify problems, find general patterns, and extract recommendations for successful management using nontraditional biomanipulation to improve water quality. There are many obstacles that prevent traditional biomanipulation from achieving expectations: expending largely to remove planktivorous fish, reduction of external and internal phosphorus, and macrophyte re-establishment. Grazing pressure from large zooplankton is decoupled in hypereutrophic waters where cyanobacterial blooms flourish. The original idea of biomanipulation (increased zooplankton grazing rate as a tool for controlling nuisance algae) is not the only means of controlling nuisance algae via biotic manipulations. Stocking phytoplanktivorous fish may be considered to be a nontraditional method; however, it can be an effective management tool to control nuisance algal blooms in tropical lakes that are highly productive and unmanageable to reduce nutrient concentrations to low levels.Although small enclosures increase spatial overlap between predators and prey, leading to overestimates of the impact of predation, microcosm and whole-lake experiments have revealed similar community responses to major factors that regulate lake communities, such as nutrients and planktivorous fish. Both enclosure experiments and large-scale observations revealed that the initial phytoplankton community composition greatly impacted the success of biomanipulation. Long-term observations in Lake Donghu and Lake Qiandaohu have documented that silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) (two filter-feeding planktivorous species commonly used in management) can suppress Microcystis blooms efficiently. The introduction of silver and bighead carp could be an effective management technique in eutrophic systems that lack macrozooplankton. We confirmed that nontraditional biomanipulation is only appropriate if the primary aim is to reduce nuisance blooms of large algal species, which cannot be controlled effectively by large herbivorous zooplankton. Alternatively, this type of biomanipulation did not work efficiently in less eutrophic systems where nanophytoplankton dominated.

scholarly journals Continuous Monitoring of Turbidity and Conductivity in Wastewater Networks

2015 ◽  
Vol 28 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Thomas Bersinger ◽  
Isabelle Le Hécho ◽  
Gilles Bareille ◽  
Thierry Pigot ◽  
Alexandre Lecomte
Keyword(s):  
Total Nitrogen ◽  
Continuous Monitoring ◽  
Oxygen Demand ◽  
Rain Event ◽  
Aquatic Life ◽  
Pollutant Concentrations ◽  
Rain Events ◽  
The One ◽  
Continuous Estimation ◽  
The Impact

Continuous monitoring of the sanitation network of the urban catchment of Pau (southwest France) has been performed since March 2012 using rain gauges, flowmeters, as well as turbidity and conductivity probes. Good correlations were obtained between turbidity, total suspended solids (TSS) and chemical oxygen demand (COD) on the one hand, and conductivity and total nitrogen on the other hand. This allowed an instantaneous and continuous estimation of pollutant concentrations and fluxes since that date. In the present paper we focused on the results of October 2012, which was characterized by alternating periods of dry and rainy events. Turbidity and conductivity raw data show different trends during the study period depending on the parameter and the rain events. A turbidity peak is observed at the beginning of each rain event but its amplitude varies with the intensity of the rain and the length of the preceding dry weather period. Conversely, conductivity decrease during each rain event implying, that rain water acts as a dilution factor. The behaviour of COD and total nitrogen differ markedly due to their partitioning between the dissolved (total nitrogen) and particulate phases (COD). Daily pollutant fluxes allow a global comprehension and monitoring of the sewer system. Important COD fluxes during a rain event preceded by a long dry weather period highlight the importance of erosion of sedimentary deposits in the sewerage network. During these events, important fluxes are discharged into receiving water leading to the question of the impact on aquatic life. Generally, these results highlight the potential of online monitoring to better understand the behaviour of the sewer network on long or short time scales. This could be a useful tool to manage wastewater treatment.

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