• Title/Summary/Keyword: Biological effectiveness

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A Comparative Study on the Conditioning and Dewaterability of Digested Sludge from Intermittent Aerobic Digestion (간헐포기 소화슬러지의 개량과 탈수 특성에 관한 비교 연구)

  • Kim, Seong Hong;Choi, Young Gyun;Chung, Tai Hak
    • Journal of Korean Society on Water Environment
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    • v.20 no.4
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    • pp.370-375
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    • 2004
  • Synthetic organic polyelectrolytes can be used to condition sludges to enhance their dewaterability. When conditioning biological sludges, the charge on the polymer has a significant impact on the effectiveness of the polymer as a conditioner. The objectives of this investigation were to determine the most effective type and dosage of polymer for conditioning digested sludge prior to dewatering, and to investigate the relationship between dewaterability and particle size. 3 types of digested sludge were used under the different digestion processes like anaerobic digestion, aerobic digestion and intermittent aerobic digestion. CST(capillary suction time), TTF(time-to-filter) and SRF(specific resistance to filtration) were tested as a dewaterability index and the number of particle distribution was analyzed using particle size analyzer. The results indicate that cationic polymer appears to be required for effective conditioning of these 3 types digested sludge and the optimal polymer dosage is about 0.6% of SS. CST and TTF are well correlated with mean particle diameter of which the dimension order is 1.7.

Cavitation Effects on Radiated Sounds and Break Efficiency Induced by Piezoelectric Extracorporeal Shock Wave Lithotripter (ESWL 장치에 의한 방사음 및 파쇄효율에 미치는 캐비테이션의 영향)

  • 장윤석
    • Journal of Biomedical Engineering Research
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    • v.22 no.2
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    • pp.205-210
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    • 2001
  • The effectiveness of extracorporeal shock wave lithotripter for the therapy of calculus has been well known in the field of urology. There are many studies about the performance of that and the influence into human body. Among them, it is an impertant issue that cavitation is always deal with shock wave. A medium of the shock wave is related to the cavitation phenomenon. In this paper, therefore, we analysis the spectra of radiated sounds and the break efficiency on focal region due to the medium of shock wave. The results show that the cavitation bubbles produce a harmful on the break efficiency and the stability of the radiated sounds due to the ESWL.

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Studies on the Biological Activity of Synbiotics: A Review (신바이오틱스의 생리활성에 관한 연구 고찰)

  • Yoon, Jin A;Shin, Kyung-Ok
    • The Korean Journal of Food And Nutrition
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    • v.31 no.3
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    • pp.319-327
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    • 2018
  • This paper defines the common features of synbiotics based on the definition of probiotics and prebiotics, and reviews the effectiveness of synbiotic food. The concept of synbiotics is defined as 'a mixture of prebiotics and probiotics that have a beneficial effect on the host, as a dietary supplement that alters living organisms in the gastrointestinal tract and improves their survival.' Synbiotic food contains ingredients with beneficial microbes that are expected to improve interactions between microbial and useful substances. Synbiotic foods may have anti-cancer and immune system-boosting effects. Improved digestion, healthier bowel movements, and overall increased intestinal health has been reported were reported after increasing the healthy microorganisms within the intestinal tract. In addition, depending on the type of food containing the symbiotic ingredients, more consistent weight control, improvement of cardiovascular health, and lower blood glucose levels may also be expected. Unlike previous studies, this review of synbiotics has shown that it is necessary for synergistic effects to take place among microorganisms and components to be further studied. Further research is needed on the safety and ingestion of microorganisms contained in synbiotics.

Effects of Pretreatment Method on the Bonding Strength of 4-META/MMA-TBB Resin to Bovine Dentin (상아질 전처리방법이 4-META/MMA-TBB계 레진의 접착강도가 미치는 영향)

  • 김교한;김영빈
    • Journal of Biomedical Engineering Research
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    • v.16 no.4
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    • pp.533-542
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    • 1995
  • The present study investigated the effectiveness of pretreatment on dentin bonding. The adhesive resin was 5% 4-methacryloyloxyethyl trimellitate anhydride (4-META) in methyl methacrylate (MMA) combined with poly-MMA powder. Polymerization of this resin was initiated by tri-n-butyl borage (TBB). Ground bovine dentin samples were etched with either an aqueous solution of 10% citric (10-0 solution) (Group I) or aqueous solution of 10% citric acid and 3% ferric chloride(10-3 solution) (Group ll ). After etching, the primer (an aqueous solution of 35% hydroxyethyl methacrylate (HEM- A) and 5% glutaraldehyde was applied on the differently etched surfaces (Group III , Group IV). The 10-0 treatment showed the lowest tensile bond strength, followed by the 10-3 treatment, primer application after the 10-0 treatment and primer application after the 10-3 treatment. The relationship among the surface morphology after pretreatment, fractured surface morphology and tensile bond strength was examined. It revealed that the surface morphology change by different pretreatment influenced the bond strength and the resulting fractured surface morphology. The correlation of tensile bond strength with the fracture morphology was explained.

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Clay-based Management for Removal of Harmful Red Tides in Korea: A Multi-perspective Approach

  • Choi, Moon-Hee;Lee, Soon Chang;Oh, You-Kwan;Lee, Hyun Uk;Lee, Young-Chul
    • Journal of Marine Bioscience and Biotechnology
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    • v.6 no.1
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    • pp.17-25
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    • 2014
  • Periodically, harmful algal blooms (HABs) have occurred, with impacts on various areas including public health, tourism, and aquatic ecosystems, especially aquacultured and caged fisheries. To prevent or manage invasions of HABs into fish farms on an emergency basis, many methods have been proposed. Frequently over the past 30 years in coastal countries, treatments of clay and clay mixed with polyaluminum chloride (PAC) and chitosan have been tested for HAB-removal effectiveness in both the laboratory and the field. In Korea, yellow loess clay (hwangto) has been dispersed using electrolytic clay dispensers, both to decrease the amount of yellow loess clay's usage in containers and enhance HAB-removal efficiency. However, this emergency method has limitations, among which is the requirement for more effective controlling agents for field applications. Thus, in this paper, we review technologies for clay-based red tides prevention and control and their limitations, and, further, introduce next-generation algicidal technologies for the emergency protection of fish farms.

Single-cell PCR on protargol-impregnated euplotid ciliates: a combined approach of morphological and molecular taxonomy

  • Kim, Se-Joo;Choi, Joong-Ki;Ryu, Seong-Ho;Min, Gi-Sik
    • Animal cells and systems
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    • v.15 no.3
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    • pp.251-258
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    • 2011
  • Ciliates are considered one of the most diverse protozoa and play significant roles in ecology. For successful taxonomic study of these microscopic eukaryotes, a staining procedure is necessary, due mainly to intrinsic difficulties in recognizing characteristics from living cells. Although molecular taxonomy has been used to resolve the ambiguities associated with traditional morphology-based taxonomy, extraction of genomic DNA from stained ciliate cells is not available yet. In the present study, we describe a method to extract genomic DNA from a single protargol-impregnated euplotid cell. By using $HgCl_2$ as a fixative and modulating the exposure time of bleach solution in the protargol impregnation, high-quality genomic DNA can successfully be extracted from a stained single cell with minimal loss of morphological integrity. This technique will contribute to the effectiveness of combined approaches of molecular and morphological taxonomy from single ciliate cells.

A Study on the Evaluation of Hydrodynamic Performance of Trileaflet Prosthetic Heart Valves (삼엽식 인공판막의 수력학적 성능평가에 관한 연구)

  • 김혁필;이계한
    • Journal of Biomedical Engineering Research
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    • v.18 no.2
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    • pp.147-156
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    • 1997
  • Various prosthetic heart valves have been developed and used clinically, but they have problems, such as thrombogenecity, hemoltsis, high cost and low durability. New types of trileaflet polymer heart valves have been developed in order to use them as inlet and outlet valves in a ventricular assist device. The aim of this study is to determine the hydrodynamic effectiveness of the newly designed trileaflet polymer valves and their feasibility for temporary use in the blood pumps. Trileaflet polymer valves are made of polyurethane, because of its good blood compatibility, high tonsil strength and good resistance to fatigue. An in vitro experimental investigation was perf'ormed in order to ev91ua1e hydrodynamic performance of the trileaflet polymer valves having different design and fabrication tech- niques. The St. Jude Medical valve (SJMV) and floating-type monoleaflet polymer valve (MLPV) were also tested The pressure drop across the valve, leakage volume, and the flow patterns mere investigated for valves. The result of comparative tests showed that the trileaflet polymer valves had a better hydrodynamic performance than the others. TPV which has two stable membrane shape showed the lowest back flow. The pressure hops of TPVs were lower than that of MLPV, but slightly higher than SJMV. The hydrodynamic performance of valves under the pulastile flow showed the similar results as steady flow. The velocity profiles and turbulent intensities were measured at the distal sites of valves using a hot-film anemometer. Central flow was maintained in trileaflet polymer valves, and the maximum turbulent intensities were lower in TPVs comparing to MLPV.

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Novel biological strategies to enhance the radiation therapeutic ratio

  • Kim, Jae Ho;Jenrow, Kenneth A.;Brown, Stephen L.
    • Radiation Oncology Journal
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    • v.36 no.3
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    • pp.172-181
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    • 2018
  • Successful anticancer strategies require a differential response between tumor and normal tissue (i.e., a therapeutic ratio). In fact, improving the effectiveness of a cancer therapeutic is of no clinical value in the absence of a significant increase in the differential response between tumor and normal tissue. Although radiation dose escalation with the use of intensity modulated radiation therapy has permitted the maximum tolerable dose for most locally advanced cancers, improvements in tumor control without damaging normal adjacent tissues are needed. As a means of increasing the therapeutic ratio, several new approaches are under development. Drugs targeting signal transduction pathways in cancer progression and more recently, immunotherapeutics targeting specific immune cell subsets have entered the clinic with promising early results. Radiobiological research is underway to address pressing questions as to the dose per fraction, irradiated tumor volume and time sequence of the drug administration. To exploit these exciting novel strategies, a better understanding is needed of the cellular and molecular pathways responsible for both cancer and normal tissue and organ response, including the role of radiation-induced accelerated senescence. This review will highlight the current understanding of promising biologically targeted therapies to enhance the radiation therapeutic ratio.

Computational Detection of Prokaryotic Core Promoters in Genomic Sequences

  • Kim Ki-Bong;Sim Jeong Seop
    • Journal of Microbiology
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    • v.43 no.5
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    • pp.411-416
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    • 2005
  • The high-throughput sequencing of microbial genomes has resulted in the relatively rapid accumulation of an enormous amount of genomic sequence data. In this context, the problem posed by the detection of promoters in genomic DNA sequences via computational methods has attracted considerable research attention in recent years. This paper addresses the development of a predictive model, known as the dependence decomposition weight matrix model (DDWMM), which was designed to detect the core promoter region, including the -10 region and the transcription start sites (TSSs), in prokaryotic genomic DNA sequences. This is an issue of some importance with regard to genome annotation efforts. Our predictive model captures the most significant dependencies between positions (allowing for non­adjacent as well as adjacent dependencies) via the maximal dependence decomposition (MDD) procedure, which iteratively decomposes data sets into subsets, based on the significant dependence between positions in the promoter region to be modeled. Such dependencies may be intimately related to biological and structural concerns, since promoter elements are present in a variety of combinations, which are separated by various distances. In this respect, the DDWMM may prove to be appropriate with regard to the detection of core promoter regions and TSSs in long microbial genomic contigs. In order to demonstrate the effectiveness of our predictive model, we applied 10-fold cross-validation experiments on the 607 experimentally-verified promoter sequences, which evidenced good performance in terms of sensitivity.

A Case of Clinical Application of Music Therapy in Patient with PTSD (외상후스트레스장애 환자에 대한 음악요법의 적용 일례)

  • Kwon, Soon-Jae;Yang, Jong-Chul;Park, Tae-Won;Chung, Young-Chul;Chung, Sang-Keun
    • Anxiety and mood
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    • v.8 no.1
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    • pp.50-54
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    • 2012
  • Music therapy had been widely used in the area of psychiatry. However recently, participation of psychiatrist has been decreased, due to recent trends of emphasizing biological psychiatry and rapid effectiveness of pharmacotherapy. A 46 years old male PTSD patient was admitted to psychiatric ward. He has suffered from PTSD symptoms, such as intrusive distressing recollection of his past traffic accident, social avoidance, insomnia and depression. Music therapy, which is conducted by a psychiatrist and a music therapist, was applied. This case suggests the positive role of music therapy in treatment of PTSD and emphasizes the importance of participation of psychiatrist, as an organizer during music therapy.