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The imbalanced use of fertilizers and irrigation water, particularly supplied from groundwater, has adversely affected crop yield and harvest quality in sugarcane (Saccharum officinarum L.). In this experiment, we evaluated the impact of potassium (K) and micronutrients [viz. Zinc (Zn), Iron (Fe), and Boron (B)] application and irrigation water from two sources, viz. canal, and tube well water on sugarcane growth, yield, and cane quality under field trails. Water samples from Mardan (canal water) and Rahim Yar Khan (tube well water) were analyzed for chemical and nutritional attributes. The results revealed that tube well water's electrical conductivity (EC) was three-fold that of canal water. Based on the EC and total dissolved salts (TDS), 83.33% of the samples were suitable for irrigation, while the sodium adsorption ratio (SAR) indicated only a 4.76% fit and a 35.71% marginal fit compared with canal water. Furthermore, the application of K along with B, Fe, and Zn had led to a significant increase in cane height (12.8%, 9.8%, and 10.6%), cane girth (15.8%, 15.6%, and 11.6%), cane yield (13.7%, 12.3%, and 11.5%), brix contents (14%, 12.2%, and 13%), polarity (15.4%, 1.4%, and 14%), and sugar recovery (7.3%, 5.9%, and 6%) in the tube well irrigation system. For the canal water system, B, Fe, and Zn increased cane height by 15.3%, 13.42%, and 11.6%, cane girth by 13.9%, 9.9%, and 6.5%, cane yield by 42.9%, 43.5%, and 42%, brix content by 10.9%, 7.7%, and 8%, polarity by 33.4%, 28%, and 30%, and sugar recovery by 4.0%, 3.9%, and 2.0%, respectively, compared with sole NPK application. In conclusion, the utilization of tube well water in combination with canal water has shown better results in terms of yield and quality compared with the sole application of canal water. In addition, the combined application of K and B significantly improved sugarcane yields compared with Zn and Fe, even with marginally suitable irrigation water. [ABSTRACT FROM AUTHOR]

The current investigation designed to estimate the bioremediation potential of plant growth-promoting rhizobacteria (PGPR) and Ag-nanoparticles. Tube well and HIT water comprising Mn and Fe above recommended values were used as treatments while tap water irrigation was treated as control. The HIT water showed 24, 200, and 64.11% higher content of Na, K Ca over control. Seeds were sterilized in 95% ethanol and soaked for 3 h before sowing in 73 h old culture of Pseudomonas stutzeri (Kx574858) @ 108 cells/ml. Phytotoxic effect of Fe and Mn reduce plant biomass and suppress photosynthetic activity indicates. The carotenoids, proline, and proline activity were 366, 450, and 678% higher in tube well water with combined PGPR and Ag-nanoparticles treatments. Pseudomonas stutzeri was more effective than Ag-nanoparticles to reduce oxidative stress with higher production of carotenoids, flavonoids, proline content, and enzyme SOD and CAT activities in HIT water. It is contingent that the high Mn and Fe bearing waste water enhance PGPR bioremediation potential to reduce metal stress in plants with synergistic action of PGPR and organic matter to alleviate oxidative stresses under metal stress. The residual effect of P. stutzeri on organic matter content of the rhizosphere soil and germination rate was higher for Momordica charantia L. This is the first statement indicating that Ag-nanoparticles oxidize Mn and Fe efficiently to reduce COD and organic matter works synergistically with PGPR and Ag-nanoparticles to enhance ROS production that increase proline, carotenoids, flavonoids, phenolics, and enzymes SOD, POD, PAL, and CAT activities to reduce oxidative stress in cucurbits. [ABSTRACT FROM AUTHOR]

A private company acquired operatorship of a brown oil field in 2020 from a National Oil Company (NOC) of India to enhance production from the field. Due to Covid-19 outbreak, operatorship was transferred in 2021. Soon as the company took over the operation, it met with surprises in terms of a smaller number of flowing oil wells due to operational reasons. However, the most disturbing was the significantly lower field water injection rate than reported by the NOC. The company undertook pressure measurement in wells to find reasons for production non-sustainability and reduced injectivity. Based on poor analysis of pressure data, the best injection well in the largest producing reservoir was interpreted to be hydrodynamically unconnected with the up-dip producers and recommended for disconnection from injection network by subsurface team to increase water injection rate from the remaining injectors. The study team reviewed the geological model and categorically ruled out discontinuity of the sand body with its up-dip producers. The Management ordered third-party review to resolve uncertainty and suggest remedial measures to improve water injection performance. The review of historical production, injection, pressure data and movement of oil water contact with time has improved the understanding of the inter and intra reservoir pressure communications in the field. The data synthesis has confirmed sand/hydrodynamic continuity between producers and injectors. Performance review of injection wells and the Water Injection Plant (WIP) have brought out bottlenecks in the system. The poor-quality injection water and the lapses in upkeeping of WIP were the primary reasons for loss of injectivity. WIP revamping and replacement of the existing oversized micron filter with smaller size have been recommended. To ensure uninterrupted water injection, conversion of one injector to pilot dump flooder has been suggested, a first of kind in India. [ABSTRACT FROM AUTHOR]

Analysis of the distribution of uranium concentrations in the water of conjugated components of the Baikal ecosystem (the water of Lake Baikal and its tributaries, headwaters of the Angara River, and groundwater from the wells drilled on Olkhon Island, and in the southwestern coastal part of Lake Baikal) has been carried out. The essential differences of the maximum uranium concentrations in groundwater of Lake Baikal and its inflows and the close average and median values of uranium in the water of Lake Baikal and the Angara River source were determined. The data obtained on the uranium distribution fix the influence of geological and geochemical peculiarities of the structure of the Baikal ecosystem and its surroundings and the climatic and catastrophic (earthquakes, seismic geodynamic activation, etc.) events that take place in the region. The changes in the uranium concentration in the water of Lake Baikal in relation to the seismic process were analyzed on the example of strong earthquakes (M ≥ 5) in the Lake Baikal area. [ABSTRACT FROM AUTHOR]

A shallow well was drilled in the East Siberian Sea for the first time with the purpose of geological study of the suture zone of deep waters of the Arctic Ocean and marginal structures of the continental shelf. The works have been carried out at the initiative of the Federal Agency on Mineral Resources (Rosnedra) in August 2022. The well was drilled by the Russian Geological Research Institute (VSEGEI) and Rosgeologia with the assistance of Rosneft and was linked to the Rosneft's long-term stratigraphic drilling program. Drilling was accompanied by continuous seismic-acoustic profiling and well thermometry. The maximum depth of the well was 472 m from the bottom of the sea floor; 147.5 m of core was taken to a depth of 268 m. Two sedimentary sequences were identified in the section: the Lower Jurassic–Lower Cretaceous gently deformed sequence and the Upper Neogene–Quaternary horizontally lying sequence. The sequences are separated by a thick unsampled interval with horizons of confined waters. The Jurassic–Lower Cretaceous sequence composes a northwestern-dipping monocline broken by faults and probably belongs to the complex filling the Zhokhov marginal trough of the Verkhoyansk–Chukotka orogen on the Eastern Arctic shelf. [ABSTRACT FROM AUTHOR]

Graph: English Brook, which parallels New York State Route 9 for miles, flows into Lake George, the Queen of American Lakes, ferrying a huge load of salt to the lake. A road salt primer Road salt "is a general term for chloride-based deicing products", explains Brendan Wiltse, a limnologist at Paul Smith's College in the Adirondacks. Another study in Orleans, New York, 434.5 kilometers northwest of East Fishkill, revealed that the highest chloride levels were in private wells "downgradient of a road salt storage facility [a salt barn], followed by wells within 30 meters of a major roadway", writes Kelsey Pieper, of Virginia Polytechnic Institute and State University, in a 2018 paper in I Environmental Science and Technology i . [Extracted from the article]

A geophysical resistivity survey was conducted in Zehri tehsil in the district of Khuzdar for the metering of subsurface hydrogeological properties of aquifers. The Schlumberger electrode arrangement was employed with the vertical electrical sounding (VES) method for subsurface exploration. Two profile lines were designated for the survey. The distance between the two profile lines was about 1500 m and each profile contained four VES stations. The results of profile one show the aquifers were encountered in fractured limestone of the Jamburo Formation of Paleocene age at an average depth of 127 m, with an average resistivity of 39.7 Ωm, and the average aquifer thickness was 54.025 m. The result of profile two shows the aquifers were encountered only in VES four in the sandstone lithology of the Ziddi Formation with a resistivity of 79.9 Ωm, at a depth of 120 m with, and a thickness of 40 m. There was no aquifer encountered in the remaining all VES. The main lithology of these VES is thick impervious compacted limestone, shale, and clay of Jurassic age from the Ziddi Formation. The current tube wells were also rapidly depleting in the study area. The main factor behind the decline of aquifers in the study area is an uncontrolled installation of tube wells and continuous pumping of tube wells for agricultural purposes badly puts stress on aquifers and directly deteriorates the quality and quantity of groundwater. [ABSTRACT FROM AUTHOR]

Key Takeaways: Garland, Texas, wanted to reduce its nonrevenue water (NRW), which had risen sharply between 2015 and 2020. Using satellite‐directed field leak inspections, the city was able to identify leaking pipes and reduce real water losses. Garland began a proactive leak detection program in 2021, and NRW has dropped significantly because of these efforts. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Accurate prediction and continuous monitoring of spatiotemporal variations in groundwater levels (GWL) are essential for sustainable groundwater resource management as it is a critical natural resource for human survival and ecosystem health. In this study, deep learning-based models, convolutional neural network (CNN), long short-term memory (LSTM), and CNN-LSTM were developed to predict GWL changes from 2003 to 2020 by integrating the gravity recovery and climate experiment (GRACE) and GRACE Follow-On (GRACE-FO) data with hydro-meteorological data sets (evapotranspiration, precipitation, and temperature). To assess the effectiveness of the developed models, ~ 1115 in-situ wells located in various parts of the Ganga River basin were chosen due to their importance in India and their reported decline in groundwater levels. Comparison of predicted GWL from deep-learning models with the in-situ data reveals that the LSTM model shows a relatively higher Pearson's correlation coefficient (PR) (0.681 on testing) and lower normalized root mean squared error (NRMSE) (0.292 on testing) values compared to the CNN-LSTM and CNN models. Further trend and seasonal characteristics of GWL predicted by the LSTM model also match well with the in-situ groundwater wells, except few parts of the Ganges basin. The negative GWL trend in the Ganga River basin suggests that the basin has been experiencing a continuous decline in the GWL due to anthropogenic groundwater withdrawal for irrigation. Sensitivity analysis of the deep-learning models suggests that GRACE played a significant role in estimating GWL prediction compared to precipitation and temperature. [ABSTRACT FROM AUTHOR]

Purpose. Development of a methodology for determining the thermal state of block inverse gravel filters manufactured using low-temperature technology during their transportation in a well based on computer and mathematical modeling. Methods. The study of hydrodynamic processes occurring during the transportation of the filter in the borehole, as well as the calculation of thermal fields in the filter body, was performed using the Ansys Fluent software package. To determine the effective thermophysical characteristics of the filter, the approaches of the heat transfer theory in porous media were applied. To investigate the thermal conditions of the filter at heat exchange with well fluid, the use of analytical solution of the heat conduction problem in a cylindrical shell, taking into account the properties of porous dispersed water-saturated medium, is proposed. Findings. The methodology for calculating the thermal state of a gravel filter during its operation in a well has been developed. For estimation of the filter surface temperature, the expression obtained on the basis of the analytical solution of the heat conduction equation, taking into account the characteristics of the porous filter medium, is proposed. Hydrodynamic and thermal fields in the borehole and the filter body during the filter transportation process in the borehole have been obtained. Originality. For the first time, the problem of heat exchange of a gravel inversion filter, manufactured by low-temperature technology in a well is considered. The influence of hydrothermal conditions in the well on the process of filter heating during its transportation in the well is shown. The hydrodynamic fields during the flow of the drilling mud around the inverse gravel filter are determined. Practical implications. The proposed approaches and results of the study allow to determine and can be used in the development of technological regulations for the use of block gravel filters produced by low-temperature technology for the equipment of hydrogeological wells. The methodology for modelling the process of two-phase inversion transition of aggregate state of the binding agent during transportation of inverted block-type gravel filter during well construction has been developed. [ABSTRACT FROM AUTHOR]

Transmissivity and hydraulic conductivity are essential parameters for understanding the behavior and characteristics of aquifers, and useful for framing of ground water sustainability and management aspects. After well construction and subsequent analysis of pumping test data (PTDA), the aquifer parameters can be determined. In the study area, the drilling methods are not anticipated for construction of tube wells uniformly, but the area has an ideal ground water recharge and flow conditions. The hydrogeological data gaps of aquifer parameters are observed in the study area. Keeping in view, the database is generated by using geo-electrical resistivity survey. Further, these are validated with ground truth (limited hydrogeological studies of yield test, existing lithological, and transmissivity data), and in this queue, other researchers had not yet been discussed for this type of terrain. The authors discussed the importance of geophysical results for generation of hydrogeological data without drilling and said about the optimal time saving, labor costs, and financial burdens. The study area is categorized in two segments based on the geological variations—Siwalik piedmont area (zone 1) and alluvial plains (zone 2). There were 30 numbers of vertical electrical soundings (VES) conducted in the area and resulted to derive the aquifer disposition and aquifer parameter (modeled transmissivity "T"). The VES-based modeled transmissivity (T) value trend follows < 1000m2/day (Siwaliks), 1000–3000 m2/day (alluvial plains), whereas the aquifer potential yield ranges are observed < 1000 lpm (Siwaliks) and 1000–1500 lpm (alluvial plains), respectively. The validated results reveal that that an aquifer's yield/discharge rate is proportional to the "T" component and also beneficial for producing hydrogeological data without drilling. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper summarizes the results of the risk analysis and characterization of the CO2 and brine leakage potential of Farnsworth Unit (FWU) site wells. The study is part of the U.S. DOE's National Risk Assessment Partnership (NRAP) program, which aims to quantitatively evaluate long-term environmental risks under conditions of significant geologic uncertainty and variability. To achieve this, NRAP utilizes risk assessment and computational tools specifically designed to quantify uncertainties and calculate the risk associated with geologic carbon dioxide (CO2) sequestration. For this study, we have developed a workflow that utilizes physics-based reservoir simulation results as input to perform leakage calculations using NRAP Tools, specifically NRAP-IAM-CS and RROM-Gen. These tools enable us to conduct leakage risk analysis based on ECLIPSE reservoir simulation results and to characterize wellbore leakage at the Farnsworth Unit Site. We analyze the risk of leakage from both individual wells and the entire field under various wellbore integrity distribution scenarios. The results of the risk analysis for the leakage potential of FWU wells indicate that, when compared to the total amount of CO2 injected, the highest cemented well integrity distribution scenario (FutureGen high flow rate) exhibits approximately 0.01% cumulative CO2 leakage for a 25-year CO2 injection duration at the end of a 50-year post-injection monitoring period. In contrast, the highest possible leakage scenario (open well) shows approximately 0.1% cumulative CO2 leakage over the same time frame. [ABSTRACT FROM AUTHOR]

Climate tipping points are a topic of growing interest in climate research as well as a frequent communication tool in the media to warn of dangerous climate change. Despite indications that several climate tipping points may be triggered within the Paris Agreement temperature range of 1.5 °C to well below 2 °C warming above pre-industrial levels, there is limited understanding of the level of public understanding of climate tipping points, the effects this knowledge may have on perceptions of risk related to climate change, and the corresponding behavioural and policy support implications. The emerging scholarship on learning, communication, and risk perceptions related to climate tipping points provides confounding evidence regarding the psychological and behavioural effects of information about climate tipping points. It remains unknown whether and under what conditions this knowledge increases concern, urgency perceptions and action intentions, or whether it might overwhelm audiences, inducing fatalism and withdrawal from public engagement. In this study, we assess the current state of knowledge about climate tipping points among Norwegians using a nationally representative survey. We study the comparative effects of communicating about climate tipping points and climate change more generally on risk perceptions among participants with a survey-embedded experiment. We find low levels of knowledge regarding climate tipping points (<20 %). Information about tipping points had somewhat stronger effects on participants’ risk perceptions compared to general information about climate change, moderately increasing concern. We discuss our findings, and the implications, and suggest directions for further research. [ABSTRACT FROM AUTHOR]

This article describes three utopian attempts to ameliorate the negative effects of income inequality that are less revolutionary than those of More and Bellamy. Rather than dispensing with money or gold, these three utopias modify existing institutions with the aim of lopping off the extremes of both wealth and poverty without upending the entire social and economic structure. Discussion includes Theodor Hertzka's Freeland (1891), Theodor Herzl's Altneuland: The Old New Land (1902), and H. G. Wells's A Modern Utopia (1905). The three utopias provide potential solutions by undercutting causes of poverty and intergenerational wealth accumulation rather than by economic leveling, and by stressing a fresh start for each generation. The primary tools in this effort are education, universal healthcare, a safety net of basic income, fiscal transparency, confiscatory estate taxes, and common ownership of land. [ABSTRACT FROM AUTHOR]

The boundary of Yellow Sea Cold Water Mass (YSCWM) is a key ocean frontal structure influencing the regional ecosystem. Complex oceanic processes such as tidal currents, upwelling, and internal waves influence fine-scale hydrological structures, comprehensively resulting in a significantly highly productive area for plankton and fisheries. However, detailed research requires inaccessible high-resolution data. To investigate the fine-scale and high-frequency effects of oceanic processes on the local hydrological and ecological environment, we conducted comprehensive cruise acoustic observations and intensive station surveys of the hydrological environment around the YSCWM boundary in summer 2021 and 2022, and found that: (1) fine-scale hydrological structures across the YSCWM boundary were directly captured through this specific intensive station observation design; (2) clear zooplankton diel vertical migration (DVM) phenomena match well with the thermocline variation, showing that acoustics are effective indicators that reflect the water mass layering structure in summer in the YS; and (3) the shear excited by internal waves during propagation and flood tides enhances the upward and downward mixing of the water mass near the thermocline, thus thickening and weakening the layer, an effect that will be more pronounced when both are present at the same time, with ebb tide having the opposite effect. Topographically influenced tidal upwelling also causes significant vertical fluctuations in isotherms. This represents a new way of studying the fine-scale hydrodynamic–hydrologic–ecological aspects of key regions through acoustic remote sensing. [ABSTRACT FROM AUTHOR]

This study proposed a structured approach that incorporates a geographical information system (GIS) with an analytical hierarchal process (AHP) for selecting the best location for drilling new artesian wells, considering water quantity and salinity, aquifer depth, distance to the area of use, the wells interfering, and land characteristics. ArcGIS software was used to manipulate the raw data to generate a thematic layer for each selection criterion. The proposed approach consists of three phases: the first phase applies regular AHP to find the best site in the study area; and the second phase utilizes the raster overlay feature of ArcGIS to find the best zone in the study area to dig a new artesian well. In the third and last phase, AHP compares the first phase best site with a set of random sites within the best-identified zone in the second phase. A case study was used to exemplify the proposed approach. It results in a sensitivity of about 15% of the original criteria weights. The study concludes that the outcomes of this approach are more trustworthy and robust, as compared to relying solely on the AHP method (phase 1) or ArcGIS (phase 2) method. [ABSTRACT FROM AUTHOR]

Groundwater temperature is one of the main factors that is considered when deciding on installation of a vapor compression refrigeration system with groundwater used for heat transfer. Groundwater temperature measurement is a necessity for the system installation. A total of 75 groundwater wells within the Chiang Mai Basin were selected for temperature monitoring stations. The temperature-depth profile of shallow groundwater showed that temperature had little change below 2 m depth from the water table. The temperature-depth profile of deep groundwater showed the separation of upper and lower temperature zones. Mostly, the temperature of the upper zone of deep groundwater has a positive slope. The temperature of the lower zone of deep groundwater is relatively constant. Both the shallow and deep groundwater temperatures are below the atmospheric temperature. The seasons, hydrogeologic units, and land use types have affected groundwater temperature of the Chiang Mai Basin only little. [ABSTRACT FROM AUTHOR]

The city of Gagal suffers from insufficient drinking water, and the population turns to surface water, wells and drillings without guarantee of quality. In order to characterize the hydrogeochemical and bacteriological properties of the waters of the aquifer system in the city of Gagal, to contribute to improving its knowledge, field campaigns were undertaken to sample the groundwater. The present study focuses on the hydrogeochemical and bacteriological characterization of drinking water in Gagal, southwestern Chad. The methodology consisted of acquiring existing data, a field campaign, and a chemical and bacteriological analysis of the water in the laboratory. The results of the physicochemical analyses revealed that the values of the parameters such as conductivity, pH (5.23), Ca² (26.11 mg/L), Mg²(5.14 mg/L), Na(3.54 mg/L), K(1.34 mg/L), HCO3 -(81.74 mg/L), Cl-(11.77 mg/L), SO4 -(1.94 mg/L), and NO3 - (8.70 mg/L) conformed to the WHO potability standards. Piper's diagram showed calcic and magnesian bicarbonate facies represented by 75%; and calcic and magnesian sulfate chloride facies in 25% of the analyzed waters. The bacteriological (Total coliforms (0 to more than 135,200 CFU/100 ml), Escherichia coli (0 and 14,400 CFU/100 ml), faecal enterococci (0 and 4600 CFU/100 ml)) study confirmed that the water from the wells and boreholes showed pollution of bacterial origin. Using these waters may endanger the populations with the risks of hydric diseases. [ABSTRACT FROM AUTHOR]

Experimentation is a common method to reveal the stick–slip vibration characteristics of horizontal well drill string system. Three different diameters of mini bits and an experimental bench of horizontal well drillstring system are innovatively designed to simulate the interaction between the bit and rock and the interaction between the drill pipe and well wall, which are the two boundary conditions that generate stick–slip vibration. The effects of bit type, drill pipe stiffness, rotational speed, and (ROP) Rate of Penetration on stick–slip vibration are investigated using rock-breaking experiments. The experimental results show that as the rotational speed increases from 9 to 45 r/min, (SSVI) stick–slip vibration intensity decreases. When the rotational speed is 9 r/min, the SSVI of the bit with higher cutter density drilling rock is lower than that of the bit with lower cutter density drilling rock. When the rotation speed is 45 r/min, the SSVI of the three bits is equal. The SSVI of drill pipe with smaller stiffness is greater than that of drill pipe with larger stiffness. The SSVI increases as the ROP increase from 0.36 to 1.26 m/h. The experimental findings aid in our understanding of the causes of stick–slip vibration. It lays the groundwork for the next step in reducing the harm caused by stick–slip vibration. [ABSTRACT FROM AUTHOR]

Several researchers have explored how landscape planning and design can effectively mitigate floods and leverage flood benefits in flooded land. However, these landscape planning opportunities are rarely used and rarely discussed in research areas. Generally, the people who live in flood-prone areas are economically dependent on this land. Hence, they come back repeatedly after every flood for their livelihood. For instance, Bangladesh, which suffers from floods due to its geographical location and topographical characteristics, has yet to learn about the opportunities available for landscape planning & design. In this research, Shahzadpur Upazila situated near the Jamuna River is considered a case, is the most vulnerable and flood-prone area in Sirajganj. Every year around 20000 people are suffering more or less in Shahzadpur. Many of them are obliged to do temporary migration and start from nothing all over again. Government management response commonly involves riverbank erosion treatment and non-government organization (NGO) funding only for installing tube wells and toilets. Moreover, the importance of bringing back resiliency in those lands is diverting backward due to a lack of knowledge and attention. Due to many challenges, the research focuses on only landscape planning & design before architecture. This paper presents a strategic framework that will discuss the challenges that need to be overcome and the opportunities to address each. The following three landscape planning strategies are discussed to reduce flood damage: raising the land, creating wetlands, and using agriculture as a buffer. Along with this, a mixed-method approach will shortlist the opportunities according to the villager's needs in terms of implementation. The approaches will introduce the possibilities coming with floods and bring back resilience to the land again. [ABSTRACT FROM AUTHOR]

Background: Biosecurity‐based interventions are important health strategies for the control of infectious disease and improve productivity in broiler. There are various reasons why broilers die at the early stages of production; however, biosecurity measures are crucial in reducing the risk of disease prevalence and can therefore affect the overall deaths in a flock for a specific period (crude mortality rate [CMR]). Objectives: This study was designed to determine the current biosecurity situation on small‐scale broiler farms in Bangladesh and its relationship to the CMR during the early stages of production. Methods: A cross‐sectional observational study was conducted on small‐scale broiler farms (N = 57) located in peri‐urban areas of Chattogram and Pabna districts of Bangladesh. Descriptive and predictive statistical analyses were performed to estimate the frequency of categorical variables and their effect on CMR. Results: The findings indicated that around 80% of small‐scale broiler farms lacked adequate biosecurity measures. Both on day 1 (p = 0.012) and on days 2–14 (p = 0.003), flocks with inadequate biosecurity had considerably higher median CMRs. Farms that were near the neighbourhood used wood shavings as bedding, offered tube well/shallow well or supply line water, maintained a brief empty period (≤5 days) before introducing new flocks and began using antibiotics on day 1 all had significantly higher CMR at both days 1 and 2–14. Conclusions: The findings point to the necessity of implementing stringent biosecurity measures in broiler production in locations where there is a shortage, which can lower the burden of arbitrary antibiotic usage and will lower total production costs due to crude mortality and management‐related issues. [ABSTRACT FROM AUTHOR]

Agricultural projects in different parts of the world depend on underground water wells. Recently, there have been many unfortunate incidents in which children have died in abandoned underground wells. Providing topographical information for these wells is a prerequisite to protecting people from the dangers of falling into them, especially since most of these wells become buried over time. Many solutions have been developed recently, most with the aim of exploring these well areas. However, these systems suffer from several limitations, including high complexity, large size, or inefficiency. This paper focuses on the development of a smart exploration unit that is able to investigate underground well areas, build a 3D map, search for persons and animals, and determine the levels of oxygen and other gases. The exploration unit has been implemented and validated through several experiments using various experiment testbeds. The results proved the efficiency of the developed exploration unit, in terms of 3D modeling, searching, communication, and measuring the level of oxygen. The average accuracy of the 3D modeling function is approximately 95.5%. A benchmark has been presented for comparing our results with related works, and the comparison has proven the contributions and novelty of the proposed system’s results. [ABSTRACT FROM AUTHOR]

Groundwater availability in the Zakho Basin faces significant challenges due to political issues, border stream control, climate change, urbanization, land use changes, and poor administration, leading to declining groundwater quantity and quality. To address these issues, this study utilized the Analytic Hierarchy Process (AHP) and geospatial techniques to identify potential groundwater sites in Zakho. The study assigned weights normalized through the AHP eigenvector and created a final index using the weighted overlay method and specific criteria such as slope, flow accumulation, drainage density, lineament density, geology, well data, rainfall, and soil type. Validation through the receiver operating characteristic (ROC) curve (AUC = 0.849) and coefficient of determination (R2 = 0.81) demonstrated the model's accuracy. The results showed that 17% of the area had the highest potential as a reliable groundwater source, 46% represented high-to-moderate potential zones, and 37% had low potential. Flat areas between rivers and high mountains displayed the greatest potential for groundwater development. Identifying these potential sites can aid farmers, regional planners, and local governments in making precise decisions about installing hand pumps and tube wells for a regular water supply. Additionally, the findings contribute to the development of a sustainable groundwater management plan, focusing on improving water usage and protecting water-related ecosystems in the region. Identification of the optimum influencing factors, arrangement of the factors in a hierarchy, and creation of a GWPI map will allow further planning for groundwater preservation and sustainability. This project can be conducted in other areas facing droughts. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Data on the geothermal resource base of Iceland are presented: 25 high-temperature (temperature over 200°C at the bottom) and 250 low-temperature (150°C) deposits. The similarity of the geological conditions and the main characteristics of thermal water intakes in Iceland and Kamchatka krai of Russia is noted. The analysis of the legal support of geothermal energy in Iceland, as well as the activities of the state institution Orkustofnun for licensing, research of geothermal deposits, and the creation of the world's largest library of geothermal literature, was carried out. The process of implementation of the IDDP state program for drilling and testing wells at the foot of the Krafla volcano at supercritical parameters (SCP) of fluids is described. The main characteristics of eight geothermal power plants (GeoPP) with a total capacity of 753 MW with electricity generation in 2021 of 6208 GW h are given and thermal schemes and cycles are described. It is indicated that the most powerful GeoPP in Iceland is Hellisheiði (303 МW), the geothermal coolant of which is supplied to Reykjavik, located at a distance of 19.5 km from it. This station is equipped with an installed system for the utilization of carbon dioxide into carbonate underground rocks. Power units with binary cycles were built at two GeoPPs: Husavik (2 MW) in the Kalina cycle and Svartsergi (7 × 1.2 MW) with organic coolant. It is noted that Iceland has the world's largest geothermal heat generation (2373 MW, 9340 GW h (2021)), with heating predominating (1650 MW; 6840 GW h (2021)). The most powerful heat-supply system in the country and in the world, in Reykjavik, is described: its capacity is 1150 MW and the length is 2230 km. Data are presented on the nonenergy use of geothermal water in fish farms, swimming pools, greenhouses, and carbon dioxide utilization plants. It is concluded that the experience of Iceland is especially significant for the development of geothermal energy in Russia. [ABSTRACT FROM AUTHOR]

Groundwater is one of the world's most important sources of fresh drinking water. Various contaminants mix with groundwater and alter its natural composition, such as arsenic. This study aimed to ascertain the present condition of arsenic concentration, its spatial pattern, and its relationship with tube well depth in the Gangni Union in the Chuadanga district of Bangladesh. Additionally, the study tried to assess the associated noncarcinogenic health risks imposed by oral ingestion of arsenic. Systematic sampling was used to collect water samples (n = 100) along with depth information from the sample tube wells. Water samples were analyzed with the pre-calibrated Hach EZ, Dual-Range Arsenic Test Kit (Range: 0.00–0.5 mg/l). Both geostatistical (spatial autocorrelation, Hotspot analysis, and IDW) and statistical (descriptive and correlation statistics) methods were used. The resultant arsenic content of the samples tested ranges from 0.0004 (mg/l) to 0.10 (mg/l). Arsenic levels in almost 42% of the samples exceeded the WHO standard, 21% exceeded the Bangladesh standard, and 37% were within the tolerable standard. Geostatistical analysis shows that approximately 63% of the total area is arsenic contaminated. Furthermore, hotspot analysis reveals that the northeastern and southeastern parts of the study area are more arsenic-contaminated than the other parts. Noncarcinogenic health risk assessment shows that children have a higher average daily dose (ADD) range (8.33E-06-0.00181) than adults (2.78E-06-0.0006). Similarly, the hazard quotient (HQ) value is also higher for children (0.0277–6.033) than for adults (0.0092–2.011). The result of Pearson's correlation coefficient, r (98) = − 0.7580, p = 0.000, shows a negative linear relationship between concentration values and depth, meaning that increasing depth will reduce arsenic contamination from tube well water. [ABSTRACT FROM AUTHOR]

A total of 27 taxons, 12 from Rotifera, 1 from Cladocera, and 14 from Copepoda, were determined in the study, which was conducted by sampling 4 times from 29 water wells. A total of 3 families were detected from Rotifera and Lecanidae was the richest family with 8 species. Among the 6 families of Copepoda, Cyclopoidae had 8 species. The rotifer species with the largest distribution areas were Lecane closterocerca (found in 15 wells), Pleuroxus aduncus, the only species from Cladocera, was found in 21 wells and Kinnecaris xanthi had the widest distribution area (found in 27 wells). In terms of total zooplankton species, it was determined that wells 3, 12, and 18 were the richest with 14 species. While Rotifera was found in limited quantities in all water wells, Pleuroxus aduncus from Cladocera, Diacyclops longuioides, Megacyclops viridis, Monchenkocyclops mehmetadami and Thermocyclops dybowski from Copepoda were found in very large quantities. In addition, the genus Ectinosoma is reported for the first time from inland waters of Türkiye with this study. [ABSTRACT FROM AUTHOR]

Peatlands are ecosystems formed mostly by organic matter and water and constitute a particular type of free aquifer. They perform important hydrological functions by storing excess water during rainfall events, contributing to the baseflow of its rivers throughout the year. Its degradation affects the water table dynamics and influences the decomposition of organic matter content and the release of carbon into its waters. The water retention capacity may also be compromised and thus reduce the volume of water available downstream, especially in the dry season. This study aimed to evaluate the effects of anthropic interference on variations in groundwater level, water storage, and carbon flow in two tropical mountain peatlands, located at the head of the Araçuaí River, in Serra do Espinhaço Meridional, Minas Gerais State, Brazil. Level meters were installed in groundwater wells distributed on peatland zones located in a protected area (Natural Park) (Protected—TP) and outside the conservation unit (Anthropized—TA). Data were analyzed considering the daily rainfall recorded by an automatic weather station installed in the study area. From the data on precipitation and water table level variation, the specific yield (Sy) in the two peatlands was calculated. The observed flows and the mean monthly Sy on each groundwater well were correlated and their significance was verified using the t-test (p < 0.05). The relationship between the observed flow and the mean monthly values of Sy obtained for the groundwater wells was verified through multiple regression. The Sy correlated significantly with the flow in both peatlands (p < 0.05). Multiple linear regression showed a coefficient of determination (R2) of 0.92 in both peatlands, indicating a direct relationship between Sy and observed flow. The TP presented a 43% smaller variation in the water table, a 7% higher Sy, and a specific flow rate of 13% higher related to the TA. The peatland located in the protected area retains more water, with less variation in flow throughout the year, and releases less carbon in the water compared to the anthropized peatland. The results demonstrate that anthropization is causing peatland degradation, reducing its water-holding capacity and accelerating its carbon losses. In the medium term, these effects may lead to a drastic reduction in flow in the upper course of the Araçuaí River. [ABSTRACT FROM AUTHOR]

The provision of clean water, microorganisms-free water is crucial in preventing the transmission of waterborne diseases. This study was conducted with the objective of evaluating the bacteriological quality of water sources accessible to students within Nasarawa State University Keffi. Sixteen samples, comprising ten from piped source, three from boreholes, and three from wells, were subjected to bacteriological quality assessment. The total bacterial count was analyzed using the pour plate technique, while the total coliform count and bacteriological index were assessed through the most probable number technique. Among the various water sources examine, pipe-borne water exhibited the lower bacterial contamination with a mean of 0.6×106 CFU/100 mL in contrast to borehole and well water sources, which recorded mean of 1.6×106 and 3.2×106 CFU/100 mL, respectively. Additionally, pipe-borne water demonstrated the lowest mean total coliform count, registering 22 MPN/100 mL. Notably, Notably, the water samples were found to harbor bacteria such as Escherichia coli, Klebsiella pneumonia, Enterobacter aerogens, and Citrobacter sp. Alarming findings from this study highlight the unsuitability of most water samples for human consumption, as they fail to meet the quality standards established by the World Health Organization. Consequently, it is necessary to implement measures aimed at safeguarding water sources from contamination and curbing the proliferation of diseases. Furthermore, it is pertinent to prioritize adequate treatment of domestic water sources prior to consumption to ensure public health and wellbeing. [ABSTRACT FROM AUTHOR]

In times of water scarcity, groundwater is a vital resource that provides an alternate source of water for human consumption. In Iraq, the quality of rivers has been greatly affected by climate change and the dwindling availability of surface water. Examining and classifying the groundwater in this region is now vital. The present study sought to incorporate the groundwater property data (drinking purpose) with a geographic information system (GIS). Eleven variables were measured in 25 wells to investigate the physio-chemical properties around the Babylon province of Iraq. On the basis of the acceptability of groundwater for drinking, GWQI was categorized into four primary groups in the results. Approximately 28% of the twenty-five wells (1811.04 km2) are of excellent quality, 24% are of good quality (1552.3 km2), 44% are of low quality (2845.9 km2), and 4% are extremely contaminated (2587.2 km2). The average GWQI for the entire study region was 110.7, making it inappropriate for human consumption. It has been determined that approximately 52% of the groundwater from the examined wells can be deemed safe for consumption, although certain measurements surpass the permissible limits. To guarantee that the residents in these areas are supplied with water of superior quality and safety, treatment of the tested groundwater is recommended before use. [ABSTRACT FROM AUTHOR]

Groundwater quality assessment is an important aspect of groundwater studies in arid environments such as Sharourah in Saudi Arabia. Sharourah governorate is located in the south of Saudi Arabia in the Empty Quarter desert. It suffers from water scarcity, and groundwater is the main source for the domestic water use. The researchers collected the samples from groundwater wells of different places in Sharourah governorate in May to august 2019. They used eighteen physical and chemical parameters to investigate the quality of the groundwater. The results showed that all parameters were below the maximum allowed according to the specifications to SASO and WHO for drinking water. The effective weight percentage and water quality index for all parameters in the samples studied were calculated according to the standards of SASO. The largest effective weights were for the parameters of Mg2 + , pH, Cl-, EC, and TDS compared to other parameters; and their mean percentage was 32.19%, 21.53%, 8.44%, 7.68%, and 6.73%, respectively. WQI values range from 38 to 70; the nine samples of the groundwater wells were classified into two categories: four wells of good water, and five of poor water. All the groundwater samples showed that the groundwater in Sharourah governorate is suitable for domestic uses, and safe for obtaining drinking water therefrom according to WQI used in this study. [ABSTRACT FROM AUTHOR]

Complex, multihazard risks such as private groundwater contamination necessitate multiannual risk reduction actions including seasonal, weather‐based hazard evaluations. In the Republic of Ireland (ROI), high rural reliance on unregulated private wells renders behavior promotion a vital instrument toward safeguarding household health from waterborne infection. However, to date, pathways between behavioral predictors remain unknown while latent constructs such as extreme weather event (EWE) risk perception and self‐efficacy (perceived behavioral competency) have yet to be sufficiently explored. Accordingly, a nationwide survey of 560 Irish private well owners was conducted, with structural equation modeling (SEM) employed to identify underlying relationships determining key supply management behaviors. The pathway analysis (SEM) approach was used to model three binary outcomes: information seeking, post‐EWE action, and well testing behavior. Upon development of optimal models, perceived self‐efficacy emerged as a significant direct and/or indirect driver of all three behavior types—demonstrating the greatest indirect effect (β = −0.057) on adoption of post‐EWE actions and greatest direct (β = 0.222) and total effect (β = 0.245) on supply testing. Perceived self‐efficacy inversely influenced EWE risk perception in all three models but positively influenced supply awareness (where present). Notably, the presence of a vulnerable (infant and/or elderly) household member negatively influenced adoption of post‐EWE actions (β = −0.131, p = 0.016). Results suggest that residential and age‐related factors constitute key demographic variables influencing risk mitigation and are strongly mediated by cognitive variables—particularly self‐efficacy. Study findings may help contextualize predictors of private water supply management, providing a basis for future risk‐based water interventions. [ABSTRACT FROM AUTHOR]

Copyright of World Water Policy is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water scarcity is a prevalent issue in Iraq, and groundwater resources are critical for addressing this problem, particularly in the country's desert regions. This study aimed to assess groundwater quality and develop spatial models using geographic information systems (GIS), inverse distance weighting (IDW), and Kriging interpolation techniques in the southwestern desert of Iraq. Water samples were collected from 75 wells, spanning an area of 50,488 km², and were analyzed during both the dry and wet seasons. The water quality characterization included measurements of electrical conductivity (EC), total dissolved solids (TDS), pH, and major cations and anions in the groundwater. Results indicated a high range of TDS values, corresponding to elevated EC levels, with pH values ranging from 7.1 to 8.3 across the study area, as revealed by the GIS models. It was found that the concentrations of major cations (Ca and Mg) and anions (HCO3, Cl, and SO4) exceeded the acceptable limits for drinking water set by the World Health Organization (WHO) and Iraqi drinking water specifications, with noticeable variations in the distribution of these elements within the study area. Furthermore, seasonal fluctuations were observed to have a significant impact on the groundwater quality characteristics. In conclusion, a wide range of water quality characteristics was identified in the study area, and the developed spatial models can serve as valuable tools for selecting appropriate treatment methods to utilize groundwater as a drinking water source. [ABSTRACT FROM AUTHOR]

The article discusses a recent study comparing the use of a stylet versus a bougie during hyperangulated videolaryngoscopy. The study found statistically significant results in favor of the bougie group, but the results were fragile, with just one patient in the bougie group potentially changing the outcome. The study's findings were also limited in generalizability due to underperformance of the stylet group compared to previous studies. The authors suggest that proper technique and equipment can make both stylets and bougies equally effective, but they recommend using bougies with a stable curve for better results. [Extracted from the article]

The depth at which groundwaters transition from fresh to more saline-the "base of fresh water"-is frequently used to determine the stringency and types of measures put in place to manage groundwater and protect it from contamination. Therefore, it is important to understand salinity distributions and compare defined bases of fresh water with salinity distributions and groundwater well depths. Here we analyze two distinct datasets: 1) a large set of total dissolved solids concentration (TDS) measurements (n = 216,754) and 2) groundwater well locations and depths (n = 399,454) across California. We find that 19 to 56% of the groundwater TDS measurements made at depths deeper than defined bases of fresh water pump fresh groundwater (TDS < 2,000 mg/L). Because fresh groundwater is found at depths deeper than the base of fresh water, current policies informed by base of fresh water assessments may not be managing and protecting large volumes of deep fresh groundwater. Furthermore, we find that nearly 4% of existing groundwater wells penetrate defined bases of fresh water, and nearly 16% of wells overlie it by no more than 100 m, evidencing widespread encroachment on the base of fresh water by groundwater users. Consequently, our analysis suggests that groundwater sustainability in California may be poorly safeguarded in some places and that the base-of-fresh-water concept needs to be reconsidered as a means to define and manage groundwater.

Past waste-disposal activities at Naval Air Station Whiting Field (NASWF) have led to elevated concentrations of contaminants in the underlying sand and gravel aquifer. Contaminants include two of the most commonly detected chemicals in groundwater in many countries (benzene and trichloroethylene (TCE)) and the “forever chemicals” per- and poly-fluoroalkyl substances (PFAS) such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). A MODFLOW model (the Whiting Field Groundwater Model (WFGM)) was previously developed for NASWF and the surrounding area to simulate groundwater flow. To obtain insight into groundwater flow pathways for the identification of potential source areas, the MODPATH particle-tracking application was applied to the WFGM for three public supply wells and three monitoring wells at NASWF. The travel time to recharge areas was estimated using concentrations of the groundwater age-dating solutes tritium (as helium ingrowth) and chlorofluorocarbons detected in the monitoring wells. Simulated travel times agree with the groundwater ages and indicate that the calibrated WFGM reasonably represents groundwater flow velocities and pathways. The MODPATH simulations confirm suspected on-base source areas to explain chemical detection in the monitoring wells. In contrast, the particle-tracking simulations indicate that potential source areas to the public supply wells include both on- and off-base sources. This is important because PFAS chemicals can have multiple sources, including land application of sludge-based fertilizers. This approach that combines groundwater age dating with particle-tracking simulations can be applied at similar sites characterized by benzene-, TCE-, and PFAS-contaminated groundwater.

Hydraulic conductivity is an essential parameter for groundwater investigation and management. A simple technique for determining the hydraulic conductivity of aquifers is the slug test, which consists of measuring the water level in a well after the sudden removal or injection of a small amount of water. The interpretation of a slug test is based on a geometry-dependent shape factor, for which various empirical relationships and approximate solutions have been proposed in the literature. In this study, shape factors are derived numerically for slug tests performed in monitoring wells with screens unaffected by aquifer boundaries. Also presented is a new approximate analytical solution for predicting shape factors for well screens with a large aspect ratio. A comparison with earlier methods reported in the literature shows that our results match or exceed them in terms of accuracy. The approximate analytical solution is promising because it is accurate and very easy to apply in practice. [ABSTRACT FROM AUTHOR]

Background: Lymphatic filariasis (LF) is a vector-borne parasitic disease which affects 70 million people worldwide and causes life-long disabilities. In Bangladesh, there are an estimated 44,000 people suffering from clinical conditions such as lymphoedema and hydrocoele, with the greatest burden in the northern Rangpur division. To better understand the factors associated with this distribution, this study examined socio-economic and environmental factors at division, district, and sub-district levels. Methodology: A retrospective ecological study was conducted using key socio-economic (nutrition, poverty, employment, education, house infrastructure) and environmental (temperature, precipitation, elevation, waterway) factors. Characteristics at division level were summarised. Bivariate analysis using Spearman's rank correlation coefficient was conducted at district and sub-district levels, and negative binomial regression analyses were conducted across high endemic sub-districts (n = 132). Maps were produced of high endemic sub-districts to visually illustrate the socio-economic and environmental factors found to be significant. Results: The highest proportion of rural population (86.8%), poverty (42.0%), tube well water (85.4%), and primary employment in agriculture (67.7%) was found in Rangpur division. Spearman's rank correlation coefficient at district and sub-district level show that LF morbidity prevalence was significantly (p<0.05) positively correlated with households without electricity (district rs = 0.818; sub-district rs = 0.559), households with tube well water (sub-district rs = 0.291), households without toilet (district rs = 0.504; sub-district rs = 0.40), mean annual precipitation (district rs = 0.695; sub-district rs = 0.503), mean precipitation of wettest quarter (district rs = 0.707; sub-district rs = 0.528), and significantly negatively correlated with severely stunted children (district rs = -0.723; sub-district rs = -0.370), mean annual temperature (district rs = -0.633.; sub-district rs = 0.353) and mean temperature (wettest quarter) ((district rs = -0.598; sub-district rs = 0.316) Negative binomial regression analyses at sub-district level found severely stunted children (p = <0.001), rural population (p = 0.002), poverty headcount (p = 0.001), primary employment in agriculture (p = 0.018), households without toilet (p = <0.001), households without electricity (p = 0.002) and mean temperature (wettest quarter) (p = 0.045) to be significant. Conclusions: This study highlights the value of using available data to identify key drivers associated with high LF morbidity prevalence, which may help national LF programmes better identify populations at risk and implement timely and targeted public health messages and intervention strategies. Author summary: Lymphatic Filariasis (LF) is particularly associated with poverty and living in a rural area, where disease transmitting mosquito vectors thrive. To better understand the socio-economic and environmental factors associated with the LF morbidity prevalence distribution in Bangladesh, this study examined publicly available data and used descriptive, statistical, and mapping methods to highlight key associations. Results found that high risk populations were those living in rural areas, employed in agriculture, with high levels of poverty, and houses without electricity or toilets, and where temperatures in the rainy season were lower than other regions of the country. These findings will help to inform public health messages and implement interventions for people affected by LF morbidity, but also to help reduce any current and future risk of transmission. This will support progress to achieving WHO elimination targets, leading to a future free of suffering for people affected by LF associated morbidity. [ABSTRACT FROM AUTHOR]

Water supplies in arid regions have traditionally been assured by cisterns, channels, wells, among other man-made structures with smooth vertical walls that can be deadly traps for several animals, including amphibians and reptiles. In this study, we investigate the incidence of such "trap structures" on the herpetofauna of the eastern Iberian Peninsula. We explored which features of these structures and which biological traits are associated with higher incidence of falling into these traps. We studied 205 trap structures and found 1224 amphibians or reptiles representing 25 different species, including endangered and protected ones. Broad-scale macroclimate and landscape variables were not associated with the incidence of traps. Instead, trap impact was influenced mainly by trap morphology and season of the year, which suggests that construction design and species phenology are the main factors to affect the incidence of a trap. Biological traits (subterranean or aquatic habits, diet, nocturnal activity or emission of reproductive calls) in some species were related to the probability of falling into these traps. Some species of snakes, lizards, and toads were more prone to fall in trap structures than other species. We conclude that trap structures can strongly impact amphibian and reptile survival, especially in arid or semi-arid regions where wells and water cisterns are widespread. [ABSTRACT FROM AUTHOR]

INTRODUCTION The pathogenic Escherichia coli bacterium that cause diseases within the intestine is called diarrheagenic E. coli (DEC) and is responsible for E. coli gastroenteritis. The present study aimed to identify the occurrence and antibiotic resistance profile of STEC/ EHEC and EPEC from water sources in the Adamawa-north Senatorial zone, Nigeria. METHODS Water samples from hand-dug wells and rivers/ streams from the study area were screened for the presence of E. coli, and diarrheagenic E. coli (DEC) by polymerase chain reactions. The antimicrobial susceptibility pattern of the DEC pathotypes was determined by Kirby-Bauer method. RESULTS Of the 256 water samples analyzed, 63 (24.6%) E. coli were isolated. Of these, 44 (69.8%) and 19 (30.2%) were isolated from river and well water sources, respectively. Of the 63 E. coli isolates recovered from the water sources, 27 (42.9%) were non-sorbitol fermenting E. coli. Of these, 24 (88.9%) isolates were of STEC/EHEC pathotypes, 2 (7.4%) were of EPEC pathotype, while shiga toxins and intimin genes were not amplified in 1 (3.7%) isolate. All the STEC and EPEC exhibited complete resistance (100%) to cotrimoxazole, ampicillin, nalidixic acid, augmentin, and ceftriaxone. However, while 13 (54.2%) out of the 24 STEC isolates demonstrated resistance to imipenem, all the EPEC isolates remained susceptible to imipenem. The resistant profile showed that the DEC pathotypes were resistant to 7-12 antibiotics with 8 (30.8%) of the 26 DEC resistant to 12 antibiotics. CONCLUSIONS The findings of this study contribute to a better knowledge of the occurrence of STEC/EHEC and EPEC in the major water sources of the study area and may serve as reference point data for future use and epidemiological surveillance. [ABSTRACT FROM AUTHOR]