42 research outputs found

    Alignment of Ti

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    In this study, magnetic field (B) was applied on TiO2 (anatase) of dye-sensitized solar cell (DSC) for alignment of crystal. Magnetic field was applied on TiO2 when deposited TiO2 on the fluorine tin oxide (FTO) was dried at 373 K for crystalline orientation. And applying time of B was varied 0~25 min. Characteristics of the magnetic field applied TiO2 films were analyzed by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). Current-voltage characteristics were also analyzed using solar simulator, and it was confirmed that the energy conversion efficiency of 41% was increased. Finally, it was identified that the magnetic field affected orientation of TiO2, resulting in the enhancement of the performance of the DSC

    Assessment of pathogenic bacteria in water and sediment from a water reservoir under tropical conditions (Lake Ma Vallée), Kinshasa Democratic Republic of Congo

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    This study was conducted to assess potential human health risks presented by pathogenic bacteria in a protected multi-use lake-reservoir (Lake Ma Vallée) located in west of Kinshasa, Democratic Republic of Congo (DRC). Water and surface sediments from several points of the Lake were collected during summer. Microbial analysis was performed for Escherichia coli, Enterococcus (ENT), Pseudomonas species and heterotrophic plate counts. PCR amplification was performed for the confirmation of E. coli, ENT, Pseudomonas spp. and Pseudomonas aeruginosa isolated from samples. The results reveal low concentration of bacteria in water column of the lake, the bacterial quantification results observed in this study for the water column were below the recommended limits, according to WHO and the European Directive 2006/7/CE, for bathing water. However, high concentration of bacteria was observed in the sediment samples; the values of 2.65 × 103, 6.35 × 103, 3.27 × 103 and 3.60 × 108 CFU g−1 of dry sediment for E. coli, ENT, Pseudomonas spp. and heterotrophic plate counts, respectively. The results of this study indicate that sediments of the Lake Ma Vallée can constitute a reservoir of pathogenic microorganisms which can persist in the lake. Possible resuspension of faecal indicator bacteria and pathogens would affect water quality and may increase health risks to the population during recreational activities. Our results indicate that the microbial sediment analysis provides complementary and important information for assessing sanitary quality of surface water under tropical conditions

    Environmental Prevalence of Carbapenem Resistance Enterobacteriaceae (CRE) in a Tropical Ecosystem in India: Human Health Perspectives and Future Directives

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    In the past few decades, infectious diseases have become increasingly challenging to treat, which is explained by the growing number of antibiotic-resistant bacteria. Notably, carbapenemresistant Enterobacteriaceae (CRE) infections at global level attribute a vast, dangerous clinical threat. In most cases, there are enormous difficulties for CRE infection except a few last resort toxic drugs such as tigecycline and colistin (polymyxin E). Due to this, CRE has now been categorized as one among the three most dangerous multidrug resistance (MDR) pathogens by the US Centres for Disease Control and Prevention (CDC). Considering this, the study of the frequency of CRE infections and the characterization of CRE is an important area of research in clinical settings. However, MDR bacteria are not only present in hospitals but are spreading more and more into the environment, thereby increasing the risk of infection with resistant bacteria outside the hospital. In this context, developing countries are a global concern where environmental regulations are often insufficient. It seems likely that overcrowding, poor sanitation, socioeconomic status, and limited infrastructures contribute to the rapid spread of MDR bacteria, becoming their reservoirs in the environment. Thus, in this review, we present the occurrence of CRE and their resistance determinants in different environmental compartments in India

    Extracellular DNA (eDNA): Neglected and Potential Sources of Antibiotic Resistant Genes (ARGs) in the Aquatic Environments

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    Over the past decades, the rising antibiotic resistance bacteria (ARB) are continuing to emerge as a global threat due to potential public health risk. Rapidly evolving antibiotic resistance and its persistence in the environment, have underpinned the need for more studies to identify the possible sources and limit the spread. In this context, not commonly studied and a neglected genetic material called extracellular DNA (eDNA) is gaining increased attention as it can be one of the significant drivers for transmission of extracellular ARGS (eARGs) via horizontal gene transfer (HGT) to competent environmental bacteria and diverse sources of antibiotic-resistance genes (ARGs) in the environment. Consequently, this review highlights the studies that address the environmental occurrence of eDNA and encoding eARGs and its impact on the environmental resistome. In this review, we also brief the recent dedicated technological advancements that are accelerating extraction of eDNA and the efficiency of treatment technologies in reducing eDNA that focuses on environmental antibiotic resistance and potential ecological health risk

    Extreme Environment <i>Streptomyces</i> : Potential Sources for New Antibacterial and Anticancer Drug Leads?

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    Antimicrobial resistance (AR) is recognized as one of the greatest threats to public health and in global concern. Consequently, the increased morbidity and mortality, which are associated with multidrug resistance bacteria, urgently require the discovery of novel and more efficient drugs. Conversely, cancer is a growing complex human disease that demands new drugs with no or fewer side effects. Most of the drugs currently used in the health care systems were of Streptomyces origin or their synthetic forms. Natural product researches from Streptomyces have been genuinely spectacular over the recent years from extreme environments. It is because of technical advances in isolation, fermentation, spectroscopy, and genomic studies which led to the efficient recovering of Streptomyces and their new chemical compounds with distinct activities. Expanding the use of the last line of antibiotics and demand for new drugs will continue to play an essential role for the potent Streptomyces from previously unexplored environmental sources. In this context, deep-sea, desert, cryo, and volcanic environments have proven to be a unique habitat of more extreme, and of their adaptation to extreme living, environments attribute to novel antibiotics. Extreme Streptomyces have been an excellent source of a new class of compounds which include alkaloids, angucycline, macrolide, and peptides. This review covers novel drug leads with antibacterial and cytotoxic activities isolated from deep-sea, desert, cryo, and volcanic environment Streptomyces from 2009 to 2019. The structure and chemical classes of the compounds, their relevant bioactivities, and the sources of organisms are presented

    Efficient Management of Fast Charging Systems Based on a Real-Time Monitoring System

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    Fast charging technology is attracting attention due to the increase in the use of batteries such as EV (Electric Vehicle), LEV (Light Electric Vehicle) and ESSs (Energy Storage Systems). Fast charging of the battery has problems such as fire, heat, and performance degradation of the battery. In the case of fast charging, a large current is applied to the battery to charge it. For this reason, information of battery voltage, battery current and temperature is important when charging a battery. Excessive current, overvoltage, and overheating beyond the standard value can cause deterioration of battery performance and a direct cause of fire. Therefore, the condition of the battery must be operated in the condition that meets the battery standard. To overcome these problems, we are trying to solve problems such as battery overheating and accidents by applying real-time monitoring technology, User Mode and Auto Control Mode. In this paper, we propose a real-time monitoring system based on the PHPOC Wi-Fi Shield. It operates to efficiently manage the charger and battery status based on real-time data, and is verified through real-time monitoring of the proposed system

    Efficient Management of Fast Charging Systems Based on a Real-Time Monitoring System

    No full text
    Fast charging technology is attracting attention due to the increase in the use of batteries such as EV (Electric Vehicle), LEV (Light Electric Vehicle) and ESSs (Energy Storage Systems). Fast charging of the battery has problems such as fire, heat, and performance degradation of the battery. In the case of fast charging, a large current is applied to the battery to charge it. For this reason, information of battery voltage, battery current and temperature is important when charging a battery. Excessive current, overvoltage, and overheating beyond the standard value can cause deterioration of battery performance and a direct cause of fire. Therefore, the condition of the battery must be operated in the condition that meets the battery standard. To overcome these problems, we are trying to solve problems such as battery overheating and accidents by applying real-time monitoring technology, User Mode and Auto Control Mode. In this paper, we propose a real-time monitoring system based on the PHPOC Wi-Fi Shield. It operates to efficiently manage the charger and battery status based on real-time data, and is verified through real-time monitoring of the proposed system

    A Novel Strategy for Monitoring a PV Junction Box Based on LoRa in a 3 kW Residential PV System

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    Recently, 3 kW residential PV (Photovoltaic) junction boxes have mainly been installed on the roof or outer wall of building. Wired and wireless monitoring systems are being implemented by RS-485 and WIFI/IoT. However, conventional monitoring systems have a communication limitation according to the distance and environment. It cannot receive any information when a failure of the PV junction box occurs. Therefore, there is a need for a strategy to determine whether the fuse and diode in the PV junction box are faulty through voltage and current sensors. In this paper, we propose a novel strategy for monitoring PV junction boxes, based on LoRa (Long Range). The TTGO LoRa32 V2.0 module with LoRa and various input and output ports is utilized. The wireless TX module transmits various data collected from the PV junction box to the RX module in real time. In addition, the RX module displays the received data on an LCD (Liquid Crystal Display) screen so that the user can intuitively identify it, and the data is recorded on the internal storage device or database in the web server. The manufactured PV junction box monitoring system was tested under a 3 kW PV system. Additionally, communication reception has stable signal intensity overall, both indoors and outdoors. In particular, it shows excellent characteristics in maintaining RSSI (Received Signal Strength Indicator) > −99 dBm and PER (Packet Error Rate) < 2.7%, up to a radius of 200 m, even in NLOS (Non Line-Of-Sight) environments. Although some packet loss occurred, it was confirmed that invisible communication was possible up to 300 m

    Phase Transformation and Evolution of Localized Surface Plasmon Resonance in Cu<sub>2–<i>x</i></sub>S Thin Films Deposited at 60 °C

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    Cu<sub>2–<i>x</i></sub>S (0 ≤ x ≤ 1) thin films deposited at low temperatures (<95 °C) have rich polymorphs due to small differences in Gibbs free energy of formation, which is critical for understanding their fundamental properties. In this work, phase transformation from djurleite to covellite is obtained by simple chemical bath deposition (CBD) without using oxidizing/reducing agents. Cu<sub>2–<i>x</i></sub>S thin films synthesized using cetyltrimethylammonium bromide as a surfactant at 60 °C for different deposition time exhibit red shift in optical absorption due to quantum size effect and blue shift in localized surface plasmon resonance in the near-infrared region originating from increased copper vacancy. The surface morphology of the Cu<sub>2–<i>x</i></sub>S thin films is influenced by the surfactant, which in turn alters the optoelectronics properties. The preferential bonding between Cu and S is determined by hydrolysis of thioacetamide to release sulfides (S<sup>2–</sup>) and disulfides (S<sub>2</sub><sup>2–</sup>) and the kinetics to reduce Cu<sup>2+</sup> to Cu<sup>+</sup> leading to mixed phase formation and an increase in surface to volume ratio. Through X-ray photoelectron spectroscopy and X-ray absorption near edge structure analysis, it is confirmed that both Cu<sup>2+</sup> and S<sup>2–</sup> are reduced with time of deposition and form covellite Cu–S<sub>2</sub><sup>2–</sup>–Cu bonds
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