• Title/Summary/Keyword: Spreading resistance

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Characterization of Extended Spectrum Beta-Lactamases (ESBL) Producing Escherichia coli Isolates from Surface Water Adjacent to Pharmaceutical Industries in Bangladesh: Antimicrobial Resistance and Virulence Pattern

  • Taslin Jahan Mou;Nasrin Akter Nupur;Farhana Haque;Md Fokhrul Islam;Md. Shahedur Rahman;Md. Amdadul Huq;Anowar Khasru Parvez
    • Microbiology and Biotechnology Letters
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    • v.51 no.3
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    • pp.268-279
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    • 2023
  • The pharmaceutical industry in Bangladesh produces a diverse range of antibiotics for human and animal use, however, waste disposal management is inadequate. This results in substantial quantities of antibiotics being discharged into water bodies, which provide suitable environment for the growth of antibiotic-resistant bacteria, capable of spreading resistance genes. This study intended for exploring the bacterial antibiotic resistance profile in adjoining aquatic environmental sources of pharmaceutical manufacturing facilities in Bangladesh. Seven surface water samples were collected from the vicinity of two pharmaceutical industries located in the Savar area and 51 Escherichia coli isolates were identified using both phenotypic and genotypic methods. Antibiotic susceptibility tests revealed the highest percentage of resistance against ampicillin, azithromycin, and nalidixic acid (100%) and the lowest resistance against meropenem (1.96%) out of sixteen different antibiotics tested. 100% of the study E. coli isolates were observed with Multidrug resistance phenotypes, with the Multiple Antibiotic Resistance (MAR) value ranging from 0.6-1.0. Furthermore, 69% of the isolates were Extended Spectrum Beta-Lactamases (ESBL) positive as per the Double Disk Diffusion Synergy Test (DDST). ESBL resistance genes blaTEM, blaCTX-M-13, blaCTX-M-15, and blaSHV were detected in 70.6% (n = 36), 60.8% (n = 32), 54.9% (n = 28), and 1.96% (n = 1) of the isolates, respectively, by Polymerase Chain Reaction (PCR). Additionally, 15.68% (n = 8) of the isolates were positive for E. coli specific virulence genes in PCR. These findings suggest that pharmaceutical wastewater, if not properly treated, could be a formidable source of antibiotic resistance spread in the surrounding aquatic environment. Therefore, continued surveillance for drug resistance among bacterial populations around drug manufacturing facilities in Bangladesh is necessary, along with proper waste disposal management.

A Study of Skid Resistance Characteristics by Deicing Chemicals (제설제 사용으로 인한 노면 미끄럼저항 특성 연구)

  • Lee, Seung Woo;Woo, Chang Wan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.5D
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    • pp.813-819
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    • 2006
  • Skid Resistance is a index to represent the friction between tire and road surface, which influences driving safety. Skid resistance varies with the conditions of tire, abrasion of road surface, vehicle speed, drying, wet and freezing condition of road surfaces. Especially, freezing occurs when temperature drops below $0^{\circ}C$ followed by snow or rain causes decrease of skid resistance. To recover the decreased skid resistance deicing work is applied. As a results of deicing works, freezing condition is changed into wet condition. However the wet road surfaces containing the remaining deicings agents may not show the skid resistance of normal wet condition. In this study, skid resistances in the condition of freezing, deicing process and deicing agents remained after snow-removal are evaluated. The test results, skid resistance recover quickly when Pre-wetted salt spreading and NaCl was used as deicing method. Skid resistance of Deicing agents remained on the road surface showed that concrete is higher than asphalt. superior effect. Recovery rate of skid resistance by comparison wet condition is 54~80%.

Experimental Study on the Frost Resistance of Concete Product (콘크리트제품의 동결저항성에 관한 실험적 연구)

  • Sugawara, Takashi;Tsukinaga, Yhoichi;Lee, Sanghun
    • 한국방재학회:학술대회논문집
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    • 2011.02a
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    • pp.91-91
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    • 2011
  • The quality of the surface layer in concrete structures plays an important role in the durability of the concrete. The concrete factory products are made as they improve the appearance of the surface and compressive strength in need. A common criterion to judge the quality of concrete products frequently seen in our daily life appears to be "beauty" in terms of consistent shaping. However, as for most concrete curb in such areas where a large amount of anti-freezing agents(NaCl) and ice and snow melting agents(CaCl2) are spread over roads to ensure road safety during the winter season, since deterioration advances from the surface, scaling is seen on the surface concrete due to deterioration which combined freezing damage and salt damage. Especially, In cold northern districts, the spreading amount of deicing salts increases by regulation of studded tire use, and the scaling of the concrete products, the various parts of concrete structures for roads is increasing in recent years. In this study, L-shape concrete curb were targeted, the permeable form method with the commercial permeable sheet was applied to it and the improvements of the quality were examined. By the permeable form method, surface layers got strengthened, which prevented permeation of the deterioration factor from the outside, and the scaling resistance of the upper surface where the permeable sheet was applied improved exceedingly. It will be expected by applying the permeable form method to various concrete products that frost resistance improves and scaling damage decreases.

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Analysis of Class 1 Integrons in Imipenem-resistant Pseudomonas aeruginosa

  • Sung, Ji Youn
    • Korean Journal of Clinical Laboratory Science
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    • v.43 no.2
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    • pp.68-74
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    • 2011
  • Pseudomonas aeruginosa is an aerobic, Gram-negative, glucose-nonfermenting bacterium, which has emerged as a serious opportunistic pathogen. Recently, outbreaks of carbapenem resistant P. aeruginosa give rise to significant therapeutic challenges for treating nosocomial infections. The genes of metallo-${\beta}$-lactamase (MBL), a powerful carbapenemase, are carried as a part of the mobile gene cassettes inserted into integrons playing an important role in rapid dissemination of antibiotic resistance genes among bacterial isolates. In this study, we investigated the prevalence of integron in imipenem resistant P. aeruginosa isolates. A total of 61 consecutive, non-duplicate, and imipenem resistant P. aeruginosa strains were isolated from a university hospital in the Chungcheong province of Korea. We employed repetitive extragenic palindromic sequence-based PCR (rep-PCR) method for the selection of clonally different P. aerusinosa strains. PCR and DNA sequencing were conducted for the detection of integrons. Twenty-one clonally different P. aeruginosa strains were isolated. Only one (P28) of the strains harbored $bla_{VIM-2}$ that was found as gene cassettes in class 1 integrons. Four of 21 carbapenem resistant P. aeruginosa strains harbored class 1 integron containing aminoglycoside resistance determinant. All of the integrons detected in the study contained more than one resistance gene cassette, which can mediate resistance to multiple antibiotics. To prevent further spreading of the multi-drug resistant P. aeruginosa, conseguent monitoring and clinical polices are required.

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Feasibility of Optoelectronic Neural Stimulation Shown in Sciatic Nerve of Rats (흰쥐의 좌골 신경 자극을 통한 광전 자극의 가능성에 대한 연구)

  • Kim Eui tae;Oh Seung jae;Baac Hyoung won;Kim Sung june
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.611-615
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    • 2004
  • A neural prostheses can be designed to permit stimulation of specific sites in the nervous system to restore their functions, lost due to disease or trauma. This study focuses on the feasibility of optoelecronic stimulation into nervous system. Optoelectronic stimulation supplies, power and signal into the implanted optical detector inside the body by optics. It can be effective strategy especially on the retinal prosthesis, because it enables the non-invasive connection between the external source and internal detector through natural optical window 'eye'. Therefore, we designed an effective neural stimulating setup by optically based stimulation. Stimulating on the sciatic nerve of a rat with proper depth probe through optical stimulation needs higher ratio of current spreading through the neural surface, because of high impedance of neural interface. To increase the insertion current spreading into the neuron, we used a parallel low resistance compared to load resistance organic interface and calculated the optimized outer parallel resistance for maximum insertion current with the assumption of limited current by photodiode. Optimized outer parallel resistance was at a range of 500Ω-700Ω and a current was at a level between 580uA and 650uA. Stimulating current efficiency from initial photodiode induced current was between 47.5 and 59.7%. Various amplitude and frequency of the optical stimulation on the sciatic nerve showed the reliable visual tremble, and the action potential was also recorded near the stimulating area. These result demonstrate that optoelectronic stimulation with no bias can be applied to the retinal prosthesis and other neuroprosthetic area.

Characterization of Screen Printed phosphorous Diffusion Paste for Silicon Solar Cells (스크린 프린팅을 이용한 태양전지 에미터 형성에 관한 연구)

  • Gong, Dae-Yeong;Yang, Doo-Hwan;Kim, Sun-Yong;Lee, Yong-Woo;Kwon, Tae-Young;Yun, Seog-Woo;Lee, Kwang-Il;Yi, Jun-Sin
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.111-113
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    • 2009
  • This paper shows that you can achieve high quality N+ emitter layers using a screen printable phosphorous diffusion paste and firing in an infrared belt furnace. Spreading resistance measurement from a beveled sample is used to measure carrier concentration as a function of depth for different phosphorous concentrations. Contours of estimated sheet resistance are shown for different processing conditions. This paper describes newly developed low cost phosphorous pastes. It shows the characterization of the newly developed phosphorous paste (DP99-038). This low cost pastes can easily be printed and make 16% efficiency.

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Analysis for Series Resistance of Amorphous Silicon Thin Film Transistor (비정질 실리코 박막 트랜지스터의 직렬 저항에 관한 분석)

  • Kim, Youn-Sang;Lee, Seong-Kyu;Han, Min-Koo
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.6
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    • pp.951-957
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    • 1994
  • We present a new model for the series resistance of inverted-staggered amorphous silicon (a-Si) thin film transistors (TFT's) by employing the current spreading under the source and the drain contacts as well as the space charge limited current model. The calculated results based on our model have been in good agreements with the measured data over a wide range of applied voltage, gate-to-source and gate-to-drain overlap length, channel length, and operating temperature. Our model shows that the contribution of the series resistances to the current-voltage (I-V) characteristics of the a-Si TFT in the linear regime is more significant at low drain and high gate voltages, for short channel and small overlap length, and at low operating temperature, which have been verified successfully by the experimental measurements.

Characteristics of Impulse Discharges in Wet Soil (습한 토양의 임펄스방전특성)

  • Kim, Hoe-Gu;Lee, Bok-Hee
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.2
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    • pp.363-369
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    • 2017
  • This paper presents the experimental results related to soil ionization and electrical breakdown in a concentric hemispherical electrode system under lightning impulse voltages. Dynamic voltage-current and impedance-time characteristics of soil ionization were measured and analyzed. Also the electrical breakdowns of the soil gap were investigated. The time-lag to the peak current corresponds to the soil ionization propagation. The time of ionization propagation in wet sand is found to decrease with increasing the impulse currents. A drastic decrease in ground resistance was observed during the impulse current spreading in sand. The electrical breakdown appears at the wave tail of impulse voltage and results in a wide scatter in V-t curves. The voltage-current curves have a fan-like shape attributed to ionization processes which result in increasing current and decreasing voltage.

Study on small resistance regions in post-liquefaction shear deformation based on soil's compressive properties

  • Jongkwan Kim;Jin-Tae Han;Mintaek Yoo
    • Geomechanics and Engineering
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    • v.36 no.3
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    • pp.295-301
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    • 2024
  • Understanding the post-liquefaction shear behavior is crucial for predicting and assessing the damage, such as lateral flow, caused by liquefaction. Most studies have focused on the behavior until liquefaction occurs. In this study, we performed undrained multi-stage tests on clean sand, sand-silt mixtures, and silty soils to investigate post-liquefaction shear strain based on soil compressibility. The results confirmed that it is necessary to consider the soil compressibility and the shape of soil particles to understand the post-liquefaction shear strain characteristics. Based on this, an index reflecting soil compressibility and particle shape was derived, and the results showed a high correlation with post-liquefaction small resistance characteristic regardless of soil type and fine particle content.

PHYSICAL PROPERTIES OF FRESH RED PEPPER

  • W. J. La;D. B. Song;Lee, S. K.;Lee, T. K.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11c
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    • pp.578-585
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    • 2000
  • Geometrical characteristics of fresh red pepper(Capsicum annuum L.) were measured and indexed to define some important geometrical characteristics, and malformation of body and fruit stalk which are necessary for the design of the equipments for cutting, spreading and alignment of red pepper in developing a fruit stalk remover of fresh red pepper. The effects of bending of body and fruit stalk on the equipments of cutting, spreading and alignment were studied. The maximum lengths of some parts of fresh red pepper were found to be 180 mm, 125 mm, 144 mm, 67 mm and 76 mm for the body, the bent part of body, the fruit stalk, the bent part and the straight part of fruit stalk, respectively. The fresh red pepper with bending indices more than 0.4 and 0.3 for the body and the fruit stalk, respectively, was defined to be malformed based on the result of cutting rate using cutting unit; while the other ones to be normal in shape. Based on this, among the total fresh red peppers tested, 47%, 40% and 20% were found malformed for the body, the fruit stalk, and for both of the body and the fruit stalk. Malformed red peppers were poorer in spreading and alignment than normal ones, and the processed quantity was decreased with increased feed rate. The required time for the malformed peppers to pass on the alignment plate inclined at 30 increased rapidly at 8.3 Hz with increased feed rate. For the fresh red peppers with average moisture content of 85%,w.b., the maximum tensile strength between fruit stalk and body was 88.1 N; the maximum cutting resistances were 92.1 N and 94.9 N for the fruit stalk-calyx joint and body, respectively. Average coefficients of static friction were 0.99, 0.62, 0.59 and OJ, respectively, for the surfaces of rubber, galvanized iron, acryl and plywood.

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