• Title/Summary/Keyword: action spectrum

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Synthesis and Antimicrobial Activity of Novel Tetrahydrobenzothienopyrimidines

  • Amal Abdel Haleem Mohamed Eissa;Ashraf Ahmed Moneer
    • Archives of Pharmacal Research
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    • v.27 no.9
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    • pp.885-892
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    • 2004
  • Due to the rapidly growing number of resistant strains of bacteria, the search for antibacterial agents with new modes of action will always remain an important and challenging task. Thus, the reaction of 2-substituted or. unsubstituted-4-(4-acetylanilino)-5,6,7,8-terahydrobenzo[b] thieno[2,3-d]pyrimidine derivatives 1-3 with the hydrazine derivatives, semi and / or thiosemi-carbazides, provided the corresponding hydrazones 4-6 and semi and/or thiosemicarbazones 7-9. Claisen-Schmidt condensation of compounds 1 or 2 with the appropriate aldehyde yielded the chalcones 10, 11 which, when treated with hydroxylamine hydrochloride gave rise to the isoxazoline-containing compounds 12, 13. Furthermore, reacting the respective chalcones 10, 11 with different hydrazines, urea and/or thiourea, furnished compounds 14, 15, 16, and 17 respectively. Representative compounds were tested for their antimicrobial activity against Candida Albicans and certain gram-positive and gram-negative bacteria. Their MICs were then determined. Compound 15e, showed a broad spectrum of activity while most of the other com-pounds showed varying antimicrobial activity.

Structure-activity Relationship Study of Fluoro-Neplanocin A as Potential Antiviral and Antitumor Agents

  • Shin, Dae-Hong;Moon, Hyung-Ryong;Choi, Won-Jun;Lee, Kang-Man;Lee, Sang-Kook;Jeong, Lak-Shin
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.245.3-246
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    • 2003
  • S-Adenosylhomocysteine hydrolase (SAH) catalyzes the hydrolysis of S-adenosylhomocysteine to adenosine and L-homocysteine and has been an attractive target for the development of broad spectrum antiviral agents. Based on the potent inhibitory activity of neplanocin A against SAH, we have reported the synthesis and novel mechanism of action of fluoro-neplanocin A. (omitted)

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Effect of road surface roughness on the response of a moving vehicle for identification of bridge frequencies

  • Yang, Y.B.;Li, Y.C.;Chang, K.C.
    • Interaction and multiscale mechanics
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    • v.5 no.4
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    • pp.347-368
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    • 2012
  • Measuring the bridge frequencies indirectly from an instrumented test vehicle is a potentially powerful technique for its mobility and economy, compared with the conventional direct technique that requires vibration sensors to be installed on the bridge. However, road surface roughness may pollute the vehicle spectrum and render the bridge frequencies unidentifiable. The objective of this paper is to study such an effect. First, a numerical simulation is conducted using the vehicle-bridge interaction element to demonstrate how the surface roughness affects the vehicle response. Then, an approximate theory in closed form is presented, for physically interpreting the role and range of influence of surface roughness on the identification of bridge frequencies. The latter is then expanded to include the action of an accompanying vehicle. Finally, measures are proposed for reducing the roughness effect, while enhancing the identifiability of bridge frequencies from the passing vehicle response.

A study on RFID technology and application of China (중국의 RFID 기술과 응용에 대한 고찰)

  • Li, Peng;Zhang, Yu;Shin, Yun-Ho;Shin, Hyun-Sik
    • The Journal of the Korea institute of electronic communication sciences
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    • v.6 no.2
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    • pp.330-336
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    • 2011
  • RFID is the item is at the core of the Internet, promoting action in the online community is a pivotal element. RFID uses radio frequency waves to automatically find the technology to track individuals and items referring to the short-range wireless technology can be included. For example, ZigBee and Bluetooth has a strong ability to track and calculate. In this study, major advances in this technology by analyzing the techniques of intensive discussions, the current progress of mankind, and the impact on the future direction of development is included.

Photocleavage of DNA by 4′-Bromoacetophenone- Pyrrole Carboxamides

  • Jeon, Raok
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2001.11a
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    • pp.79-79
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    • 2001
  • Genotoxic chemotherapeutics are irreversible DNA targeting agents, which can act as anticancer and antiviral drugs. Natural antibacterial and anticancer enediynes function through the formation of free radicals formed by Bergman-type cycloaromatization and being capable of cleavage of DNA strand. They have been focused primarily on the design and syntheses of simple enediyne structures, which can be mimic their mechanistic feature. Recently. I have been reported the possible application of 4'-bromoacetophenone as a simple photoactivatable DNA cleaving agent, which could be readily prepared and exhibit potent and selective DNA cleaving activity. Herein, we further investigated the activity of 4'-bromoacetophenone-pyrrolecarboxamides, which consist of both DNA cleaving element and recognition unit under various conditions in order to get more understanding of the mechanism of the action and find a broad spectrum of application.

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A EMG Signal Analysis by the Short Time Fourier Analysis (시간 푸리에 해석에 의한 근전신호 해석)

  • Shin, Seung-Hyun;Lim, Hyun-Su;Huh, Woong
    • Proceedings of the KOSOMBE Conference
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    • v.1989 no.05
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    • pp.61-65
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    • 1989
  • In this paper, a method of the measument the degree of the musule fatigue by Short Time Fourier Analysis of the EMG signals from human biceps in the action state is proposed. For this purpose, fatigue state and recovery state of 10 persons EMG signals are sampled. And then spectrum centroids are analyzed with respect to the change of sample time window. As result of 10 persons experiment, we know that person A is most good recovery stale.

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Seismic design and assessment of steel-concrete frame structures with welded dissipative fuses

  • Calado, Luis;Proenca, Jorge M.;Sio, Joao
    • Steel and Composite Structures
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    • v.35 no.4
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    • pp.527-544
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    • 2020
  • This research presents the design and numerical assessment of composite steel-concrete frame structures with welded dissipative fuses. The assessment has been carried out based on linear response spectrum, nonlinear static pushover and time history procedures. The analytical expressions which define the envelope of the nonlinear response of the dissipative fuses are first presented and calibrated against experimental results available in literature. The assessment is then carried out according to a design methodology proposed herein. Outcomes of the numerical assessment indicate that the use of welded dissipative fuses successfully limited damage within the replaceable parts. Furthermore, although structures with dissipative fuses present lower strength and, generally, lower displacement capacity, their displacement ductility and global dissipative performance are generally higher than conventional structures, especially when the structure with dissipative fuses presents a dissipative configuration adjusted to the bending moment distribution diagram calculated for the applied seismic action.

Study of antimicrobial activity and the mode of action of Anal P5 peptide

  • Park, Yoonkyung;Hahm, Kyung-Soo
    • Journal of Integrative Natural Science
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    • v.1 no.1
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    • pp.47-53
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    • 2008
  • In a previous study, we showed that Cecropin A (1-8)-Magainin 2 (1-12) hybrid peptide (CA-MA)'s analogue, Anal P5, exhibit broad-spectrum antimicrobial activity. Anal P5, designed by flexible region (positions 9, 10)-substitution, Lys- (positions 4, 8, 14, 15) and Leu- (positions 5, 6, 12, 13, 16, 17, 20) substitutions, showed an enhanced antimicrobial and antitumor activity without hemolysis. The primary objective of the present study was to gain insight into the relevant mechanisms of antimicrobial activities of Anal P5 by using flow cytometric analysis. Anal P5 exhibits strong antifungal activity in a salt concentration independent manner. In addition, Anal P5 causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy, supporting its antibacterial activity. Its potent antibiotic activity suggests that Anal P5 is an excellent candidate as a lead compound for the development of novel antibiotic agents.

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Flavonoids: Broad Spectrum Agents on Chronic Inflammation

  • Lim, Hyun;Heo, Moon Young;Kim, Hyun Pyo
    • Biomolecules & Therapeutics
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    • v.27 no.3
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    • pp.241-253
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    • 2019
  • Flavonoids are major plant constituents with numerous biological/pharmacological actions both in vitro and in vivo. Of these actions, their anti-inflammatory action is prominent. They can regulate transcription of many proinflammatory genes such as cyclooxygenase-2/inducible nitric oxide synthase and many cytokines/chemokines. Recent studies have demonstrated that certain flavonoid derivatives can affect pathways of inflammasome activation and autophagy. Certain flavonoids can also accelerate the resolution phase of inflammation, leading to avoiding chronic inflammatory stimuli. All these pharmacological actions with newly emerging activities render flavonoids to be potential therapeutics for chronic inflammatory disorders including arthritic inflammation, meta-inflammation, and inflammaging. Recent findings of flavonoids are summarized and future perspectives are presented in this review.

Numerical Simulation of Irregular Airflow within Wave Power Converter Using OWC by Action of 3-Dimensional Irregular Waves (3차원불규칙파동장하의 진동수주형 파력발전구조물에서 불규칙공기흐름의 수치시뮬레이션)

  • Lee, Kwang-Ho;Park, Jung-Hyun;Kim, Do-Sam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.3
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    • pp.189-202
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    • 2012
  • An Oscillating Water Column (OWC) wave generation system uses the air flow induced by the vertical motion of water column in the air chamber as a driving force of turbine. It is well known that OWC is one of the most efficient devices to harness wave power. This study estimated the air flow velocity from the time variation of the water level fluctuation in the air chamber under regular wave conditions using 3-dimensional numerical irregular wave tank (3D-NIT) model that can simulate the 3-dimensional irregular wave field. The applicability of the 3D-NIT model was validated by comparing numerically predicted air flow velocities with hydraulic experimental results. In addition, the characteristics of air flow frequency spectrum variation due to the incident frequency spectrum change, and the variations of frequency spectrum and wave reflection due to the existence of converter inside the air chamber were discussed. It is found that the phase difference exists in between the air flow velocity and the water level fluctuation inside the air chamber, and the peak frequency of the spectrum in water level fluctuation is amplified by the resonance in the air chamber.