Applied and Environmental Microbiology • 2021

Bioelectrochemical Nitrogen Fixation by Pseudomonas stutzeri Increasing attention is being given to bioelectrochemical nitrogen fixation for its energy-saving property and high selectivity. Chen et al. (e01998-20) demonstrated that the diazotroph Pseudomonas stutzeri A1501 can produce extracellular NH4 without chemical suppression or genetic manipulation when the extracellular electrode is used as the sole electron donor, and the electron uptake pathway from the extracellular electron-donating partner to P. stutzeri was mediated by its endogenous redox electron shuttle phenazines. Since both P. stutzeri and potential electron-donating partners are abundant in diverse soils and sediments, this finding has broader implications for the improvement of nitrogen fertilization in the natural environment.

, Anucha Koedtruad

• 2012

The electrical conductivity and oxygen permeation of Ca2+, Zn2+ and Mg2+-doped La0.3Sr0.7Co0.9Fe0.1O3 (LSCF) were investigated. The synthesized materials were characterized by XRD, XPS and XAS. LSCFs were synthesized by modified citrate method and studied for the effect of sintering temperature. LSCF sintered at 1200 oC showed the higher oxygen permeation rate and more idealized cubic structure than others. By replacing La3+ and Sr2+ ions of LSCF with Ca2+ ions, La0.3Sr0.7-xCax Co0.9Fe0.1O3 (X = 0 - 0.7) and (La0.3Sr0.7)1-xCaxCo0.9 Fe0.1O3 (X = 0 - 0.4) were successfully synthesized. La0.3Sr0.7-xCaxCo0.9Fe0.1O3 showed pure perovskite phase with primitive cubic form when X = 0 - 0.5 whereas (La0.3Sr0.7)1-xCaxCo0.9Fe0.1O3 exhibited pure perovskite phase with primitive cubic and tetragonal forms when X = 0-0.2 and X = 0.3 - 0.4, respectively. La0.3Sr0.5Ca0.2Co0.9Fe0.1O3 showed the highest electrical conductivity in this work due to a lot of IS Co4+ and HS Co3+. To improve oxygen permeation of La0.3Sr0.5Ca0.2Co0.9Fe0.1O3, Co3+ and Fe3+ ions were replaced with Zn2+ and Mg2+ ions to obtain La0.3Sr0.5Ca0.2Co0.9-yMyFe0.1O3 and La0.3Sr0.5Ca0.2(Co0.9Fe0.1)1-y MyO3 (M = Zn2+, Mg2+, Y = 0 - 0.05). Only La0.3Sr0.5Ca0.2Co0.9-yZnyFe0.1O3 (Y = 0 - 0.03) were achieved as pure perovskite phase with primitive cubic structure. The oxygen permeation rate was increased with increasing Zn2+ content because high spin Co2+,3+ and oxygen vacancies were increased.

Farzaneh Rezaei, Saeid Esmaeili

IET Renewable Power Generation • 2024

Commercial off‐the‐shelf (OTS) photovoltaic systems coupled with battery energy storage units (PV‐BES) are typically designed to increase household self‐consumption, neglecting their potential for voltage regulation in low voltage distribution networks (LVDNs). This work proposes an enhanced sensitivity‐based combined (ESC) control method for voltage regulation, using BES control as level 1 and reactive power compensation as level 2. A centralized controller manages charging/discharging intervals, while local inverters handle real‐time power rates and reactive power, ensuring effective LVDN voltage regulation. The BES set points are obtained concerning the measured local bus voltage and according to enhanced sensitivity coefficients. The enhancement algorithm ensures that the full capacity of BES is utilized and that there is adequate capacity during charging and discharging time intervals. The proposed method, tested on 8‐bus and 116‐bus LV test feeders, outperforms OTS and an adaptive decentralized (AD) control method by completely preventing overvoltage issues, minimizing various changes in the direction of BES power, and reducing voltage deviation without significantly affecting consumers' grid dependency.

S. Pandey, Bhim Singh

2020 IEEE 5th International Conference on Computing Communication and Automation (ICCCA) • 2020

This paper deals with a grid integrated PV (Photovoltaic)-BES (Battery Energy Storage) system ensuring the interruption free power to critical loads with mode transfer capability and power quality enhancement even at distorted grid voltage condition. This PV-BES system feeds pre-specified power to the distribution network at the presence of the generation from PV panel and BES at peak load hours, stores energy in BES during light load hours, thus enhances the utility grid stability and benefits the consumer. The modified first order filter (MFOF) based control, which estimates the amplitude of fundamental frequency load current, and the grid voltage in-phase unit template is used to synchronize the PV-BES system to the distribution network in absence of either generation from the PV panel or BES at the grid tied mode. The load voltage magnitude and nature are regulated by the voltage control in a standalone mode operation. The bidirectional DC-DC converter allows a bidirectional flow of power, thus it enables either charging or discharging of the battery according to generation from the PV panel in the grid integrated mode, and provides an uninterrupted power to critical loads in absence of the PV generation and/or the grid. The synchronization mode control is utilized to transfer from the grid tied mode to islanded mode and vice versa.

S. Tyagi, Bhim Singh

2021 IEEE 2nd International Conference on Smart Technologies for Power, Energy and Control (STPEC) • 2021

With the enhancement in the demand as well as number of the electric vehicles (EV) worldwide there is a need for the development of the charging infrastructure for the smooth operation of the EV’s. This work deals with the integration of charging infrastructure to a 3P4W photovoltaic (PV)-small hydro energy conversion (SHEC)-battery energy storage (BES) based microgrid to provide power to the local loads, as well as incorporating AC and DC charging. The generated PV power is utilized locally to increase the self-consumption rate whereas the constant power generated from the SHEC is used to feed AC loads and EV’s connected at the common point in conjunction with the utility grid. Besides, the system provides dual mode operation i.e standalone as well as grid tied mode and operates seamlessly between both the modes. The controller scheme implemented suppresses the high neutral current due to the uneven distribution of the single phase loads besides, providing other functions such as improving the power quality performance of the grid, undisrupted power to the loads, mitigation of harmonics and reactive power compensation. The system is simulated and the results are presented under various scenarios.

D. Chandrashekar, P. Satish Kumar

International Journal Of Scientific Research In Engineering & Technology • 2025

n order to satisfy local load demands, this study investigates a stand-alone renewable energy system that consists of a photovoltaic (PV) plant and a battery energy storage system (BES). To improve power extraction efficiency, the PV system makes use of Sliding Mode Control (SMC) in conjunction with Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT). The BES is linked at a common DC bus to ensure system stability and continuous power supply. To improve energy conversion, an anti-windup proportional-integral (AWPI) controller is deployed in the inverter control system for active power regulation and harmonic reduction. This approach significantly minimizes Total Harmonic Distortion (THD) in inverter voltage and current, leading to superior power quality. The effectiveness of the system is confirmed by simulation results, which show improved performance in harmonic mitigation and renewable power consumption. The findings confirm that integrating SMC-based MPPT and AWPI inverter control enhances stability, efficiency, and reliability, making it a viable solution for sustainable power generation.

Niyungeko Antoine

Management and Economic Journal (MEC-J) • 2021

The objective of this study is to investigate the relationship between ease of doing business score (EDBS) and cost of business start-up procedures (CBS), age dependency ratio (ADR), strength of legal rights index (SLRI), time required to get electricity (TRGE), domestic credit to private sector (DCPS), and start-up procedures to register a business (SPRB). Since 2004, the World Bank evaluates 190 economies based on business regulatory indicators ignoring other factors that may be related to business environment. This paper investigates new factors related to EDBS ignored by the World Bank since 2004. The results of correlation analysis show a negative and significant correlation between EDB and CBS, ADR, TRGE, and SPRB. Nevertheless, a positive and significant correlation was found between EDB and SLRI and DCPS. The linear regression model finds that SLRI and DGPS affected EDB positively and significantly. However, TRGE and SPRB affected negatively to EDB. Asian policymakers should reinforce SLRI and increase DCPS. However, they should also reduce TRGE and SPRB to improve EDB. Further research should be conducted on other regions and test also other factors.

Andie Nugent, Steven Allison

• 2024

Urban ecosystems, although highly altered by humans, host diverse microbiomes that support vital ecosystem processes. While microbial ecologists are beginning to understand the drivers of microbial assembly and the link between community structure and function in many ecosystems, few of these advances have been applied to urban ecosystems. In this synthesis, we review research on the urban soil microbiome and develop a framework to integrate soil microbial communities with urban ecosystem function. We identify disturbance, altered resources, and heterogeneity as key drivers through which urbanization affects soils and soil microorganisms. Steep environmental gradients in many urban systems present a unique opportunity to address fundamental questions in microbial ecology, such as how microbes respond to stress and how biogeochemical rates relate to microbial diversity and composition. Answering such questions will help develop practical and equitable strategies for managing ecosystem benefits in cities where billions of people live.

Joseph P. Salanitro

Encyclopedia of Environmental Microbiology • 2003

Abstract Introduction and Statement of the Problem Properties of Oxygenates Observations on the Microbial Metabolism of MTBE Proposed Biodegradation Pathway for MTBE Prospects and Challenges for the Bioremediation of Fuel Ethers

P. Deines, R. Sekar, H. S. Jensen et al.

• 2010

Abstract. Microbiology in Urban Water Systems (MUWS) is an integrated project, which aims to characterize the microorganisms found in both potable water distribution systems and sewer networks. These large infrastructure systems have a major impact on our quality of life, and despite the importance of these systems as major components of the water cycle, little is known about their microbial ecology. Potable water distribution systems are large, highly interconnected and dynamic, and difficult to control. Sewer systems are also large and subject to time varying inputs and demands. Their performance also faces increasing loading due to increasing urbanization and longer-term environmental changes. Therefore, understanding the link between microbial ecology and any potential impacts on short or long-term engineering performance is important. By combining the strengths and research expertise of civil-, biochemical engineers and molecular microbial ecologists, we aim to link the abundance and diversity of microorganisms to physical and engineering variables so that novel insights into the ecology of microorganisms within both water distribution systems and sewer networks can be explored. By presenting the details of this multidisciplinary approach, and the principals behind the molecular microbiological methods and techniques that we use, this paper will demonstrate the potential of an integrated approach to better understand urban water system function and so meet future challenges.

Fuel Cells Bulletin • 2018

Canadian-based Hydrogenics has received an order, valued at US$7.8 million, to supply hydrogen PEM fuel cell power systems for zero-emission vehicles in China, with shipments expected to be made over the next 12 months. The customer has chosen to remain confidential at this time.

Aaron Bradshaw

• 2023

More-than-human, multispecies, and animals’ geographic accounts of the city have tended to focus on large, charismatic, and wild organisms, to the detriment of spatially invisible other-than-humans central to urban reproduction. At the same time, urban microbial geographies have foregrounded embodied interactions between humans and microorganisms, whether they are symbiotic or pathogenic, often marginalising the material contributions of extracorporeal microbiomes to the urban fabric. Building from these two blindspots, this article focuses on microbial ecologies that live constitutively outside of (other-than-)human bodies and which are intimately caught up in the metabolic intensities and infrastructural environments of the urban realm. There are two key aims: 1) to explore different forms of urban microbial ecologies and 2) to examine their relationships with urban infrastructures and reproduction. My disciplinary lenses are animals’ geographies and urban ecology and my case study focuses on urban water metabolism. Thus, based on empirical fieldwork on the urban river Lea in East London, and supplemented by scientific literature and technical documents, I analyse three urban microbial ecologies that correspond to the urban realms ‘extended microbiomes’: those involved in slow sand filtration for the treatment of drinkable water, those involved in sewage treatment via the activated sludge process, and those emerging and evolving in disused urban canal infrastructure. These processes spatially manage microbial growth and modulate the distribution of different forms of microbial agency with important effects for the smooth functioning of urban water metabolism. Yet, considering the specific materiality and ecological agency of microbes points to a more-than-human contingency and indeterminacy at the centre of urban reproduction. Urban human-microbial co-evolution and is mired with uncertainties, ‘black boxes’, and unintended consequences.

Hu Ren, Chun-Hui Pu, Chang-jian Lin et al.

Journal of Electrochemistry • 2013

Charge transfer is one of the essential life processes.In the past decades,the electrochemical methods have been developed to study life science in a unique physicochemical view and have exhibited abundant and precious information beyond conventional biological techniques.As bioelectrochemical research areas evolved from the fundamental studies of biomolecules' electrochemical behaviours in non-living conditions to the living cells in intro and in vivo,and further to the single molecule in living systems,the role of instruments becomes more and more crucial.The performances of instruments such as sensitivity,resolution(time,spatial and eneygy resolutions) and controllability are more demanding in the living conditions and at small size.In this review,the current statuses of the bioelectrochemical instruments,especially those for electrochemical studies at single living cell level,are presented;and the prospects of the domestic bioelectrochemical instruments are discussed.

Florian Walder, Marcel van der Heijden

• 2025

A critical asset of healthy soils is a rich and functionally diverse microbiota, yet many agricultural practices - including frequent pesticide use and insufficient organic amendments - risk compromising this biological foundation. In this contribution, we present results from two complementary studies conducted on more than 100 farms in Switzerland to investigate how pesticide application and compost use affect the diversity, composition and structure of soil microbial communities. Using a combination of molecular analyses (16S/ITS rRNA amplicon sequencing, quantitative PCR of functional genes), soil physicochemical properties and indicators for soil functions, we found that pesticide residues are associated with shifts in microbial community composition and, in some cases, reduced bacterial diversity. Conversely, farms that regularly apply compost show increased fungal richness and more complex microbial networks than reference farms. By linking these changes in microbial community traits to soil functional indicators - such as soil respiration and aggregate stability - we could shed light on the interrelationships of soil biodiversity, physicochemical properties, and soil functions, as well as the influence of agricultural management.

, Anuj Yadav, Suresh Chandra et al.

Madras Agricultural Journal • 2013

Studies were conducted to prepare Ready To Serve beverage from banana pulp with the sugar level i.e. 1.25, 1.00 and 0.75 kg /kg of pulp. The desired amount of sugar was added and blended with pulp/juice in the ratio of 10.75(T1), 11(T2) and 11.25(T3). The RTS bottles were stored under refrigeration condition (5oC), BOD incubator (25oC) and room temperature (30-35oC), up to 90 days to determine the effect of sugar ratio on quality of banana (RTS) beverage. The qualities were evaluated for fresh as well as stored samples after 15, 30, 45, 60, 75 and 90 days of storage. The TSS, acidity and optical density of banana RTS beverage increased with increase in the storage periods on particular temperatures. It was observed that the microbial growth increased with increase in the temperatures and storage period irrespective of storage conditions.

M. Rahman, H.S. Dutta

Agricultural Reviews • 2022

New revolutions have been taking place in agriculture since pre-historic times to increase agricultural production and meet the demands of rising population. The last revolution or green revolution has increased the overall production of all agricultural components but has led to several long-term environmental problems. Almost 62% of vegetables and 82% of fruits are found to have pesticide residues, which can affect our health in different ways. This have arisen the fear of eating raw fruits and vegetables and led to sublethal effects on natural enemies and pollinators. So, it is the very need of hour to look for sustainable approaches to control the plant diseases. Most of the plant pathogens are seed borne and disseminated. Thus, they affect the plants during pre-emergence stage or cause seedling damping off resulting in 100% crop loss. Under sustainable practices, microbial seed coating is an evolving precision technology. It enhances the shelf-life and activity of beneficial microbes and thereby decrease the use of harmful chemical pesticides and fertilizers. Natural products such as biochar, chitosan, peat, acacia gum, natural dyes from flowers Phutuka, Polash, Khoyar, Kodam can be used to manufacture microbial seed coats manually. Agribusiness firms Incotec, Novozymes and Monsanto have also led to developing of coated seeds laced with promising microbes. Thus, adoption of microbial seed coating can be a cost effective and efficient strategy in organic horticultural production.

Benoit St-Pierre

Microorganisms • 2023

Ruminants represent a highly successful group of herbivores that have not only evolved to thrive across a wide range of habitats, but have also played a central role throughout human history [...]

, RAMALAKSHMI A, ANTHONI RAJ S et al.

Madras Agricultural Journal • 2008

The premonsoon sowing of millets, pulses and cotton is a practice adopted in most of the rainfed area where the seeds are sown well ahead of monsoon and remain in the soil until receipt of rain. The seeds remain buried in dry soil for 2-3 weeks and germinate after the receipt of the rains if the season is normal and the farmers are lucky. Otherwise, they have to take up another sowing particularly when rain is delayed beyond a month. The seeds remain in the soil and subjected to heat stress and information on the survival of biofertilizer organisms inoculated on the seeds is much limited. Therefore the present study was undertaken to know whether the inoculants survive or perish on treated seeds in the transient period between sowing and monsoon rains.

, RAJASEKARAN P

MADRAS AGRICULTURAL JOURNAL • 1981

An experiment was conducted to study the effect of incorporation of fish and chicken wastes on comparative biogas production and distribution of microorganisms. The treatments had equel quantity of cattle dung and water mixed with old slurry and fish and chicken wastes in to proportion of 4: 1: 1. Two sets of experiments were conducted le, one set kept above ground and the other kept burried in soil, for 12 weeks and gas generated were measured for every 24 hours. The fish wastes Incorparated above ground. (4: 1: 1) gave the maximum average gas output of 1088 cc/day over 12 weeks compared to 899 cc/day of chicken wastes. Similarly the maximum bacterial population of 47,0 x 100/0 was estimated in fish wastes kent on the ground compared to chicken slurry (338x 104/g) fish clurry wae to found to have fish celluloytic activity and also produced fish methanogenic activity.

Sara König, Thomas Reitz, Ulrich Weller et al.

• 2022

<p>Mechanistic simulation models are an essential tool for predicting soil functions such as nutrient cycling, water filtering and storage, productivity and carbon storage as well as the complex interactions between these functions. Most soil functions are driven or affected by soil organisms. Yet, biological processes are often neglected in soil function models or implicitly described by rate parameters. This can be explained by the high complexity of the soil ecosystem with its dynamic and heterogeneous environment, and by the range of temporal and spatial scales these processes are taking place at.</p><p>Here, we meet these challenges and present our approach for integrating biological microscale processes into soil modelling. We introduce our systemic soil model BODIUM which simulates relevant microbial processes at the profile scale to analyse the impact of different agricultural management and climatic conditions on soil functions. For this, BODIUM includes different microbial pools as well as C:N stoichiometric considerations but does not explicitly account for microbial community structure or composition dynamics. In our approach, soil structure dynamics at the pore scale is a critical factor for controlling the availability of carbon and nutrients as well as the distribution of water and oxygen, which in turn jointly drive microbial growth and activity. To explore the potential advantage of BODIUM, we compare our model approach with traditional modelling approaches without explicit microbial activity under different simulation scenarios. We further analyse the impact of changing microclimatic conditions of water, oxygen and nutrient availability as dedicated by a dynamic soil structure on microbial activity and the corresponding soil functions.</p><p>Finally, we discuss ongoing developments to additionally consider, e.g., microbe-fauna-interactions, microbial feedback on soil structure dynamics, and phosphor dynamics.</p>

, Maria Kazou, Alkmini Gavriil et al.

Burleigh Dodds Series in Agricultural Science • 2022

Milk, which is a basic component of the human diet since millennia worldwide, is rich in all kind of nutrients, thus comprises an excellent growth substrate for both beneficial and harmful microorganisms. As a result, milk contains numerous microorganisms deriving either from the animal itself or from the environment during the collection and storage of milk. These microbes can play a number of roles, such as facilitating dairy fermentations, promoting health, causing spoilage or even disease. For decades, the microbial ecology of dairy products has been based on the study of microbial isolates through conventional culture-dependent microbiological analysis. However, culture-independent approaches, and, most importantly, high throughput sequencing coupled with the omics-based techniques enable a thorough taxonomic fingerprinting of the dairy microbiota. This chapter provides a broad overview on the microbiota of raw cow's milk, as this has been described so far by both culture-dependent and -independent approaches.

, SUBRAMANIA IYER G, RAJASEKARAN P et al.

Madras Agricultural Journal • 1983

Experiments carried out to study the succession of microbial communities in the rotting of jute and mesta with varying quantities of water revealed variations in their distributions. The bacterial population showed an increasing trend with the progress of retting until comple- tion. Wider variations were observed in the distribution of yeast, fungal and pectolytic bacteria. The anaerobic bacteria was found maximum during the 10th day. The acid forming bacteria differed with PH and varying levels of acids produced during the retting process. A combination of different groups of efficient organisms might be helpful in quickening the process of retting.

, Willem J. Ravensberg

Burleigh Dodds Series in Agricultural Science • 2021

Microbial bioprotectants have the potential to play a major role in the future of crop protection. Agriculture needs to become more sustainable and still provide food security within planetary borders. New technologies and scientific discoveries can unravel the interactions between the plant, the microbiome and the soil and provide new opportunities for crop protection and more resilient cropping systems. Regulatory issues delay and hamper exploitation and research of genetic resources. This chapter describes the factors that promote the use of microbial bioprotectants as well as those that hamper their further adoption. A sustainable and resilient agriculture depends on the microbial interactions between plants in promoting plant growth and combatting biotic and abiotic threats. The transition to a resilient agriculture requires big changes in policy, regulation and farming practices. This chapter assesses the future outlook for the methods for controlling plant diseases described in this book as well as the factors determining their uptake and success.

, Gopal H., Natarajan T. et al.

Madras Agricultural Journal • 2009

Use of microbial inoculants to enhance the nutrient uptake of any traditional medicinal plant is prerequisite to keep its medicinal value. In order to optimize the microbial inoculants for ashwagandha Withania Somnifera (L) Duna nutrient management, experiments were conducted. The effective strains of Azospirillum, Azotobacter, Bacillus and Pseudomonas isolated and characterized from different medicinal plants of Tamil Nadu were evaluated for ashwagandha under pot-culture condition. The results revealed that combined inoculation of A. lipoferum - AAs-11, Azotobacter - AAz-3, Bacillus - APb-1 and Pseudomonas fluorescens - APs-1 enhanced the biochemical constituents of ashwagandha such as chlorophyll, protein and total alkaloid contents compared to single and other combinations. Further, this bioinoculant package along with panchakavya spray enhanced the rhizosphere microbial activity of ashwagandha. It is concluded that these microbial inoculants in combination with panchakavya is the best organic nutrient management package for ashwagandha

Y. Xia, X. Sun, R. Tao et al.

• 2021

In order to investigate the distribution and risk of microbial aerosols in residential areas after the COVID-19 in Wuhan Ctiy, Changqing Garden residential area, a mature community was selected as a case in this study. From October to December 2020, the Andersen-sixstage microbial air sampler was used to collect samples in six typical places in this residential area, and the microbial aerosol concentration was determined by the plate count method. In addition, the health risk assessment was evaluated according to the Chinese Population Exposure Parameters Manual (Adult Volume). The results showed that: (1) The concentration of microbial aerosol can be ranked in this order: fresh food market >underground parking lot >food street >central basketball court >central square >green pavilion. (2) The concentration of bacteria and fungus aerosol was different in different places, and the maximum aerosol concentration occurred in the fresh food market ((1525.32±1311.31) CFU/m3) and the food street ((1296.82±113.84) CFU/m3), respectively. (3) Take the air microbial concentration in typical places as the evaluation standard: the central basketball court, green pavilion and central square were clean, the fresh food market and underground parking lot were slightly polluted, and the food court was lightly pollution. (4) The median diameter of microbial aerosols was less than 4.7 μm, which can easily cause lower respiratory tract infections in residents. (5) The Hazard Quotient (HQ) of the typical places from October to December 2020 was less than 1, indicating that the health risk of microbial aerosol exposure in Changqing Garden residential area was relatively small. This research shows that the air quality of the Changqing Garden residential area is good under the epidemic prevention and control normalized measures, which meets the requirements for sanitary conditions in the post-COVID-19 era. © 2021, Editorial Board, Research of Environmental Sciences. All right reserved.

R. Abdullah, T. Rafique, A. Kaleem et al.

International Journal of Biosciences (IJB) • 2015

A leafy vegetable particularly spinach locally known as palak, has been part of human diet for many years. Pakistan stands among top ten spinach producing countries in the world and contributes considerably to the income. However, lack of proper storage facilities and microbial attack result in post-harvest losses. Food irradiation reduced storage losses, extended shelf life and improved microbiological and parasitological safety of foods. In present study, flat leaf variety of spinach was exposed to various gamma radiation doses (0.5, 0.75 and 1.0 kGy). The microbial flora of spinach before and after irradiation was analyzed to determine significant changes in the population of spoilage microorganisms. In the present study 0.75 kGy proved to be the most beneficial in reducing the microbial flora without affecting the sensory properties of flat leaf spinach and extended the shelf life up to 4days. So, this study can be useful in shelf life enhancement for export purpose.

Asmus Olesen, Rafel Pinilla-Redondo, Mads Hansen et al.

• 2021

Horizontal gene transfer via plasmids is important for the dissemination of antibiotic resistance genes among medically relevant pathogens. Specifically, the transfer of IncHI1A plasmids is believed to facilitate the spread of antibiotic resistance genes, such as carbapenemases, within the clinically important family Enterobacteriaceae . The microbial community of urban wastewater treatment plants has been shown to be highly permissive towards conjugal transfer of IncP1 plasmids. Here, we tracked the transfer of the P1 plasmid pB10 and the clinically relevant HI1A plasmid R27 in the microbial communities present in urban residential sewage entering full-scale wastewater treatment plants. We found that both plasmids readily transferred to these communities and that strains in the sewage were able to further disseminate them. Furthermore, that R27 has a broad potential host range, but a low host divergence. Interestingly, although the majority of R27 transfer events were to members of Enterobacteriaceae , we found a subset of transfer to other families, even other phyla. Indicating, that HI1A plasmids facilitate horizontal gene transfer both within Enterobacteriaceae , but also across families of especially Gammaproteobacteria, such as Moraxellaceae , Pseudomonadaceae and Shewanellaceae . pB10 displayed a similar potential host range as R27. In contrast to R27, pB10 had a high host divergence. By cultivative enrichment of the transconjugant communities, we show that sewage strains of Enterobacteriaceae and Aeromonadaceae can stably maintain R27 and pB10, respectively. Our results suggest that dissemination in the urban residual water system of HI1A plasmids may result in an accelerated acquisition of antibiotic resistance genes among pathogens.

Adekunle Gregory Fakunle, Akinkunmi Paul Okekunle, Johnson Oluwaseun Ogundare et al.

Indoor and Built Environment • 2025

Despite the health outcomes associated with exposure to indoor microbial aerosols, the environmental factors contributing to indoor microbial proliferation in residential environments have not been extensively investigated. This study assessed factors associated with indoor bacterial and fungal aerosols in residential apartments within Ibadan, Nigeria. A 12-month survey on housing characteristics and estimation of indoor bacterial and fungal aerosols was carried out in a sample of 356 residential apartments in Ibadan using a standardized home walkthrough checklist and an indoor sampling method. Indoor levels of microbial concentration, total bacterial count, total fungal count, richness ( R ) and Simpson diversity ( D ) were assessed and categorized as either high (>median) or low (≤median) exposures. The results showed that occupant density (adjusted odds ratio (aOR) = 1.03, 95% confidence interval (CI) = 1.01–1.05; aOR = 1.04, 95%CI = 1.02–1.06; aOR = 1.04, 95%CI = 1.02–1.06), leaking roofs (aOR = 2.51, 95%CI = 1.52–4.27; aOR = 1.79, 95%CI = 1.13–2.88; aOR = 1.85, 95%CI = 1.17–2.97) and visible dampness (aOR = 4.67, 95%CI = 2.21–10.34; aOR = 4.37, 95%CI = 2.22–8.81; aOR = 4.28, 95%CI = 2.17–8.59) were independently associated with higher levels of bacterial concentrations, richness and diversity respectively. Culturally relevant interventions targeted at these factors would be promising in managing microbial proliferation in residential environments.

Victor Henry Azubuike Enemor, Precious Ebuka Okeke, Uchechukwu Chibuzo Ogbodo

Asian Journal of Research in Biochemistry • 2020

Water is very important to the existence of humans though could also serve as vehicle for pathogenic organisms and dangerous organic and inorganic matters. The physicochemical and microbial analyses of selected borehole water samples in Awka residential areas were conducted with the aim of ascertaining suitability or otherwise for human consumption. The total hardness, pH, alkalinity, some common elements and presence of toxic metals were determined by standard methods of American Public Health Association. The presence of microorganisms in the water samples was also determined. Results of the physicochemical analysis of the borehole water samples showed a mean pH value of 5.52 below the WHO standard of 6.5 - 8.5 and mean total hardness of 150 ppm greater than the WHO standard of 70 ppm. The microelements such as manganese, zinc, lead, selenium, nickel and cadmium were found to be below detectable levels in the water samples. Five bacteria species were isolated and identified in the water samples as Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli and Klebsiella pneumoniae. The physicochemical properties and the bacteria load of most of the water samples indicate that they were unfit for human consumption as the samples were outside WHO reference standard for potable water suggesting a need for increased awareness for improved sanitation and hygiene practices in the state.

G Hill

Fuel and Fuel System Microbiology: Fundamentals, Diagnosis, and Contamination Control • 2003

THE OLD MAXIM, THAT ANY TEST result is only as good as the sample, is never more true than for analysis of samples drawn for the investigation of microbiological contamination in fuels and fuel systems. Probably more than any other fuel contamination type, microbial contamination will tend to have a highly heterogeneous dispersion that is likely to be in a continual state of change. There may be changes in the overall numbers of microbes present, their viability (and culturability), the relative numbers of the predominant types (genera and species) and the amounts of microbial biomass present [1]. These changes may be due to the microbial activity itself or as a consequence of tank or system operating activities. It is thus apparent that both the timing of sampling operations and selection of appropriate sampling points need careful consideration and planning. In order that those conducting the analyses can put the best possible interpretation on the results obtained, as much information as possible about the sampling needs to be conveyed to the testing laboratory.

E. M Kholodova

Izvestiya MGTU MAMI • 2013

There was conducted a study of microbial fuel cells in the industrial waste water in the flow and periodic mode.

, Avi Roy Chowdhury, Jayendran Venkateswaran et al.

12th Simulation Workshop (SW25) Proceedings • 2025

Modeling complex global health systems, such as infectious disease dynamics, requires balancing detail with abstraction. A hybrid simulation approach combining System Dynamics (SD) and Agent Based Modeling (ABM) to study bacterial infection spread at both individual and population levels is presented. SD model captures within-host dynamics, focusing on bacterial growth, immune responses, and antibiotic treatment. ABM introduces individual variability and interactions, enabling simulation of infection spread among a population of agents. This integrated framework connects within-host and population-level dynamics, providing a foundation for adding layers of complexity. By simulating different scenarios, the model offers insights into infection dynamics and strategies for managing bacterial infections and antibiotic resistance at the community level.

Kelvin Sewake, Joseph DeFrank

HortScience • 1992

Anthurium bacterial blight is a disease that has devastated much of the Hawaii anthurium industry in recent years. In response to the crisis, the Cooperative Extension Service produced a video entitled “Strategies for Anthurium Blight Control - A Growers' Discussion.” The video format was selected to allow the extension service to utilize experience of four successful large scale commercial growers and deliver blight control information to other growers with a graphic demonstration on control procedures for disease management. Production of the video eliminated the need for farm tours, eliminated the risk of disease spread, condensed information, and allowed growers to borrow copies. This video proved effective in prompting growers to adopt and implement recommended blight control procedures.

R. POFFÉ, W. MERTENS

International Journal of Food Science & Technology • 1988

Summary Cooled raw bulk milk samples were examined for total bacterial count after 3 days at 30°C, and the numbers of psychrotrophs and proteolytic psychrotrophs after 10 days at 7°C. Positive correlations were found between the total bacterial count and the numbers of psychrotrophs, enumerated on standard plate count (SPC) agar (r = 0.88, n = 65), and between the numbers of psychrotrophs counted on SPC agar and on milk agar, respectively (r = 0.89, n = 59). Only 30.4% of the bacteria were psychrotrophs but the regression shows that the percentage of psychrotrophs increases when the total bacterial count rises. On average only small differences were found between the counts of psychrotrophs on SPC agar and milk agar, suggesting that in most samples the same organisms were probably enumerated on both media. The numbers of proteolytic bacteria were less well correlated with the numbers of psychrotrophs (r = 0.65, n = 56), as wide variations occurred between the samples. It is suggested that the total bacterial count at 30°C can be a useful estimate of the number of psychrotrophs.

John C. Schilling

Journal of Milk and Food Technology • 1956

Determination of logarithmic averages of bacterial counts is a necessary and laborious task in grading raw and pasteurized milk. As the plate count determination replaces the methylene blue test for the ever increasing number of bulk milk producers, the problem becomes greater. A slide rule type of device has been developed that may materially simplify this task. This method is explained with information relative to its principle, application, accuracy, and advantages.

Yakup Cuci, Sait Çelik

International Journal of Chemistry and Technology • 2021

Chlorpyrifos is an solid organophosphorus pesticide widely used in agriculture. It is relatively stable to hydrolysis in neutral pH and acidic aqueous solutions. Stability decreases with increasing pH. Chlorpyrifos practically insoluble in water, but highly soluble in most organic solvents such as acetone xylene and methyl bromide. It is an effective skin, stomach and respiratory insecticide and is effective against aphids, spider mites, soil bugs and house pests. It is also highly toxic bees and fish. Most pesticides are complex organic molecules and are persistent in the environment, either biota or accumulate in the environment. In pesticide-used areas, the pesticide itself or its residues are transported by rain and irrigation water and mixes into groundwater. The effects caused by the pesticide are closely related to the level of accumulation. During the studies, contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. In this study, the biodegradation potential of chlorpyrifos with P. Putida was investigated in the batch stirred reactor. In the optimum conditions, the maximum pesticide removal rate was determined as 1.51 mg/g. d. m.o.h.

Albert E. Dimond, James G. Horsfall

Rubber Chemistry and Technology • 1943

Abstract The recent article by ZoBell and Grant notes the attack of rubber by bacteria under conditions of high moisture. It is suggested that “the life of rubber products which come in contact with moisture may be prolonged if ways can be found to retard or prevent the activity of rubber oxidizing microorganisms”. In the compounding of rubber commercially, native rubber is mixed with a number of chemicals, each of which serves a specific purpose in the properties of the finished product. Among these are accelerators which lower the temperature and shorten the time of vulcanization and lengthen the life of rubber. Two well-known accelerators are mercaptobenzothiazole and tetramethylthiuram disulfide. These compounds have been tested for their ability to inhibit germination of fungi, and gross observations have been made on their ability to inhibit bacterial growth. Mercaptobenzothiazole is a moderately good fungicide, and tetramethylthiuram disulfide is excellent. The latter compound is now being marketed as a seed protectant and for the prevention of turf diseases. Both of these materials have been tested, under field conditions prevailing in Connecticut, by the authors for their efficacy in controlling plant diseases. Mercaptobenzothiazole, although inferior to tetramethylthiuram disulfide, has given partial plant disease control.

Claude E. ZoBell, Carroll W. Grant

Rubber Chemistry and Technology • 1943

Abstract In studying the biological oxygen demand of sea water, it has been observed that rubber stoppers increase the amount of oxygen consumed. In fact, the small amount of rubber gasket exposed to the water in citrate of magnesia bottles perceptibly increases the amount of oxygen consumed after 5 to 10 days' incubation. Heat-sterilized as well as formaldehyde-preserved controls proved that the increased oxygen consumption is attributable to biological activity. One-gram samples of various kinds of rubber, cut in small pieces to give a surface area of approximately 10 sq. cm., were placed in 160-cc. glass-stoppered bottles. After sterilizing in an autoclave at 120° C for 20 minutes, the bottles were filled with sterile water saturated with oxygen. Half the bottles were inoculated; the others were left sterile. Duplicate bottles were analyzed for oxygen immediately by the Winkler technique, and the others were incubated in the water bath for one to five days at 22° C, after which the amount of oxygen consumed was determined. It was necessary to decant or siphon the water from the rubber before treating it with the Winkler reagents because free iodine reacts with rubber.

А. Yu. Gusarova, Yu. V. Prosvetov, О. A. Kovalenko

Modern medical technology • 2019

A clinical case of conducting a diagnostic searching a patient with suspected recurrence of pulmonary tuberculosis in the absence of bacterial excretion is presented in the article.

, , Padraigin Murphy

• 2011

Prebiotics are selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microbiota that confers benefits upon host well-being and health’ It is not the prebiotic by itself but rather the changes induced in microflora composition that is responsible for its effects. Several sources of prebiotic were used in this study, namely extracellular polysaccharides (EPS) originating from Lactic Acid Bacteria (LAB), barley, oat. Laminaria digitata. Laminaria hyperborea and Saccharomyces cerevisiae. EPS-producing LAB were isolated from a wide variety of environmental and gastrointestinal niches. The strains were typed and classified according to their EPS-producing ability and selected strains were identified for possible commercial potential. Nevertheless, because of the constraints in terms of prebiotic yield from LAB, the cereal, seaweed and yeast were chosen better as sources of polysaccharide for large animal studies where their influence on gut microflora could be studied in a more meaningful way. In these cases, the polysaccharides were glucans - a heterogeneous group of (3-linked polyglucoses and which have attracted the attention of the pharmaceutical and functional food industry because of their positive effects on animal and human health. The prebiotic properties of cereal, algal and yeast P-glucans were thus investigated at the microbiological and molecular level on the Lactobacillus, Bifidobacterium (potential probiotics populations) and enterobacterium group in the mammalian gastrointestinal tract. Throughout the thesis, the effects of supplementing porcine diets with various forms of these polysaccharides were evaluated using conventional plating and denaturing gradient gel electrophoresis (DGGE). These results clearly showed the interspecies fluctuations of the lactobacilli, bifidobacteria in some cases in response to the diets, and it also documented the effects on members of the enterobacteria. Research and development of these biotic products have helped pave the way towards finding a successful replacement for antibiotic growth promoters (AGP) during the weaning phase of pig production.