• 제목/요약/키워드: bacteria and virus

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양전하가 부가된 수처리 필터의 입자제거특성에 관한 연구 (A Study on the Positively Charged Filter for Removing Fine Particles in Water)

  • 정성학;김종원;김상희;전병헌;이승갑;이재근;안영철
    • 설비공학논문집
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    • 제24권5호
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    • pp.454-460
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    • 2012
  • The purpose of the present work is to investigate the removal characteristics of positively charged filters for capturing negatively charged particles such as bacteria and virus in water. In order to reduce the pressure drop and increase the filtration efficiency, the filter media, modified by charge modifier having positive functional groups, is developed and evaluated. Improved liquid filters have been developed with the modified surface charge to capture and adsorb particles by electrokinetic interaction between the filter surface and particles contained in an aqueous liquid. The positively charged filter media is composed of glass fiber, cellulose and poly-ethylenimine resin for positively charging with the variation of volume ratio. The zeta potential value of the positively charged filter is +37.92 mV at the glass fiber and cellulose content ratio of 50 : 50 with resin content of 100%, while that of the PSL test particle is -23.5 mV at pH 7. The removal efficiency of the electro-positively charged filter is 98% for PSL particles of 0.11 ${\mu}m$, while that of the negatively charged filter is 7%. The positively charged filter media showed the potential to be an effective method for removing fine particles from the contaminated water for liquid filtration.

침지형 MF 중공사막을 이용한 하수 2차 처리수의 재이용 연구 (Treatment of Secondary Municipal Wastewater by Submerged Hollow Fiber MF Membranes for Water Reuse)

  • 현승훈;김응도;홍승관;안원영;임성균;김건태
    • 상하수도학회지
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    • 제19권1호
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    • pp.47-52
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    • 2005
  • This study was conducted to evaluate the performance of submerged hollow fiber MF processes to treat secondary wastewater for water reuse. Specifically, membrane productivity and filtrate water quality were investigated under various operating conditions (i.e. flux, recovery, and backwash rate) at pilot-scale. Membrane fouling became more severe with increasing flux and recovery, suggesting that low flux operation (< 25 LMH) was desirable. At high flux operating(> 37.5 LMH), increasing backwash rate showed only limited success. The biofouling, quantified by PEPA and BFHPC, was also significant in wastewater reclamation, and biogrowth control by chlorine, were necessary to improve membrane productivity. Filtrate water qualities are in good compliance with water reuse regulations regardless of operating conditions (flux, recovery and backwash rate). Particle (e.g. turbidity) removal ranged from 89 to 98%, while only 11 to 21% of organics (e.g. NPDOC) were removed by MF membrane. Only small improvement in biostability (e.g. AOC) was achieved by MF system, and thus, without post disinfection, significant microorganisms might be present in the filtrate due to regrowth. Lastly, in order to further investigate pathogen removal, controlled microbial challenge tests were performed by monitoring Giardia, Cryptosporidium, bacteria and virus, and showed relatively good microbial removal.

치성 협부 봉와직염의 증상으로 발현된 Sweet 증후군; 증례 보고 (SWEET SYNDROME INITIALLY MANIFESTING ODONTOGENIC BUCCAL CELLULITIS; REPORT OF A CASE)

  • 김용진;변수환;김준영;안강민;전주홍;이부규
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제29권6호
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    • pp.538-542
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    • 2007
  • Sweet syndrome is characterized by acute onset of fever. neutrophilic leukocytosis, painful erythematous plaque on the face and extremities, infiltration of mature neutrophils in the dermis. Cutaneous lesion and clinical symptoms rapidly improve after treatment with systemic corticosteroids. The cause of sweet syndrome is unknown but the associations with hypersensitivity to bacteria, virus, or tumor antigen have been reported. Sweet syndrome itself can be a premonitory manifestation of malignancy, so diagnostic work up for other internal malignancy is recommended. Because of fever and leukocytosis, cutaneous infections are important differentials. Sweet syndrome can be divided into 4 categories according to associated disease and symptom. (Idiopathic Sweet syndrome, Parainflammatory Sweet syndrome, Paraneoplastic Sweet syndrome, Pregnacy associated Sweet syndrome.) Sweet syndrome is relatively rare disease and the association with myelodisplastic syndrome has been reported. We report a case of Sweet syndrome associated with myelodisplastic syndrome which has initial manifestation of odontogenic buccal cellulites.

소아에서 마이코플라즈마 폐렴의 예기적 진단 (Presumptive Diagnosis of Mycoplasma pneumoniae Pneumonia in Children)

  • 이창언;박수진;김원덕
    • Journal of Yeungnam Medical Science
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    • 제29권2호
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    • pp.89-95
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    • 2012
  • Background: As Mycoplasma pneumoniae pneumonia has increased in Korea, its relevance to infants, toddlers, and adolescents has magnified as well as. However, it is difficult to perform the serological test and PCR test routinely for diagnosis in actual clinical practice. Thus, the authors conducted this study to help clinicians do presumptive diagnosis of Mycoplasma pneumoniae pneumonia using clinical, radiological, and hematological findings. Methods: The study population consisted of 224 children between 1 month and 14 years old, hospitalized for radiographically confirmed pneumonia. Patients were divided into two groups of 100 children with Mycoplasma pneumoniae pneumonia, as diagnosed using the ELISA method. Groups with negative result in Mycoplasma IgM antibody test were classified into the viral group (98 patients with respiratory virus) and the bacterial group (46 patients with the bacteria detected in the blood sputum culture or antibiotic treatment except macrolide improved the patient's condition). These groups were compared and analyzed using clinical, hematological, and radiographic differences and scoring system. Results: Clinical, hematological, and radiographic characteristics of Mycoplasma pneumoniae pneumonia have shown the intermediate level results between bacterial pneumonia and viral pneumonia. In terms of scoring system, the mean score of Mycoplasma pneumoniae pneumonia was 4.23, which was the intermediate level between bacterial pneumonia (mean score=6.67) and viral pneumonia (mean score=1.48). Conclusion: Results suggest that the combination of the scoring system information can increase the accuracy in the diagnosis even if they may have difficulties on diagnosis, because clinical manifestations, hematological, and radiographic findings are nonspecific.

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Status of Membrane Filtration in Japan : Application for Water Supply

  • Minami, Katsuyoshi
    • 한국막학회:학술대회논문집
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    • 한국막학회 1997년도 심포지움시리즈 Jan-97 수처리용 분리막 기술 및 응용
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    • pp.55-62
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    • 1997
  • In Japan, the membrane filtration is becoming a common technology for municipal water supply system especially for small plant. 6 years before (1991), the national research project of membrane filtration for small plant has started. The project was named as "MAC 21", MEMBRANE AQUA CENTURY 21. In the project the Ministry of Health and Welfare, 8 universities and 18 water treatment plant companies have been involved. This was the first attempt to research a common theme in joint with government, universities and private companies. After three years, the guide line for membrane filtration application for small plant has been established. This has promoted to install some actual plant. And also, another joint research for "RESEARCH OF MEMBRANE FILTRATION FOR ADVANCED WATER TREATMENT" has started in 1994 and completed in March, 1997. The project was named as MAC21. In the former project the main objectives were removal of turbidity and bacteria from water. However, in new project the objective was establishment of the further advanced membrane filtration technology which would be applicable for trace chemical components removal such as tri-halo-methane pre-courser, agricultural chemicals removal, offensive smell and taste removal and virus removal. For the objectives, application of nanofiltration and hybrid-system, a combination of micro-filtration ultra-filtration with biological, ozone and activated carbon treatment process have been studied. In addition, application of membrane filtration for treatment of back-wash waste water originated from membrane filters and conventional sand filters has.been studied. At the end of March of this year, about 30 membrane filtration plants are actually supplying the water, the total treatment capacity is about 6,000 m$^{3}$/day and another 20 will be installed within one year.led within one year.

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A Waterborne Outbreak and Detection of Cryptosporidium Oocysts in Drinking Water of an Older High-Rise Apartment Complex in Seoul

  • Cho, Eun-Joo;Yang, Jin-Young;Lee, Eun-Sook;Kim, Se-Chul;Cha, So-Yang;Kim, Sung-Tek;Lee, Man-Ho;Han, Sun-Hee;Park, Young-Sang
    • Parasites, Hosts and Diseases
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    • 제51권4호
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    • pp.461-466
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    • 2013
  • From May to June 2012, a waterborne outbreak of 124 cases of cryptosporidiosis occurred in the plumbing system of an older high-rise apartment complex in Seoul, Republic of Korea. The residents of this apartment complex had symptoms of watery diarrhea and vomiting. Tap water samples in the apartment complex and its adjacent buildings were collected and tested for 57 parameters under the Korean Drinking Water Standards and for additional 11 microbiological parameters. The microbiological parameters included total colony counts, Clostridium perfringens, Enterococcus, fecal streptococcus, Salmonella, Shigella, Pseudomonas aeruginosa, Cryptosporidium oocysts, Giardia cysts, total culturable virus, and Norovirus. While the tap water samples of the adjacent buildings complied with the Korean Drinking Water Standards for all parameters, fecal bacteria and Cryptosporidium oocysts were detected in the tap water samples of the outbreak apartment complex. It turned out that the agent of the disease was Cryptosporidium parvum. The drinking water was polluted with sewage from a septic tank in the apartment complex. To remove C. parvum oocysts, we conducted physical processes of cleaning the water storage tanks, flushing the indoor pipes, and replacing old pipes with new ones. Finally we restored the clean drinking water to the apartment complex after identification of no oocysts.

Isolation and Characterization of Oligotrophic Bacteria Possessing Induced Systemic Disease Resistance against Plant Pathogens

  • Han, Song-Hee;Kang, Beom-Ryong;Lee, Jang-Hoon;Kim, Hyun-Jung;Park, Ju-Yeon;Kim, Jeong-Jun;Kim, Young-Cheol
    • The Plant Pathology Journal
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    • 제28권1호
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    • pp.68-74
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    • 2012
  • Biocontrol microbes have mainly been screened among large collections of microorganisms $via.$ nutrient-rich $in$ $vitro$ assays to identify novel and effective isolates. However, thus far, isolates from only a few genera, mainly spore-forming bacilli, have been commercially developed. In order to isolate field-effective biocontrol microbes, we screened for more than 200 oligotrophic bacterial strains, isolated from rhizospheres of various soil samples in Korea, which induced systemic resistance against the soft-rot disease caused by $Pectobacterium$ $carotovorum$ SCC1; we subsequently conducted in $planta$ bioassay screening. Two oligotrophic bacterial strains were selected for induced systemic disease resistance against the $Tobacco$ $Mosaic$ $Virus$ and the gray mold disease caused by $Botrytis$ $cinerea$. The oligotrophic bacterial strains were identified as $Pseudomonas$ $manteilii$ B001 and $Bacillus$ $cereus$ C003 by biochemical analysis and the phylogenetic analysis of the 16S rRNA sequence. These bacterial strains did not exhibit any antifungal activities against plant pathogenic fungi but evidenced several other beneficial biocontrol traits, including phosphate solubilization and gelatin utilization. Collectively, our results indicate that the isolated oligotrophic bacterial strains possessing induced systemic disease resistance could provide useful tools as effective biopesticides and might be successfully used as cost-effective and preventive biocontrol agents in the field.

Anti-inflammatory Effects of Ponciri Fructus Extracts on Raw 264.7 Cells

  • Lee, Jin Wook;Jung, Hyuk-Sang;Sohn, Youngjoo;Kang, Yoon Joong
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2018년도 춘계학술발표회
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    • pp.91-91
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    • 2018
  • Poncirus Fructus (PF) is obtained by drying the trifoliate orange fruit belonging to the Rutaceae family. In our country of medicine, PF has been used as a treatment of indigestion, allergy and inflammation. But Mechanism and medical data for PF is insignificant. Recently, the effect of the study PF of biological activity was reported, such as anti- thrombosis, anti-bacteria, anti-virus, anti- allergic. We investigated that the effect of PF on anti-inflammatory in murine macrophage-like cell line Raw264.7 cells. Our results show that the expression level of Nitric Oxide (NO) and Matrix-metallopeptidase-9 (MMP-9) significantly decreased. Moreover, to determine the expression level of pro-inflammatory cytokines such as Tumor Necrosis Factor ($TNF-{\alpha}$) and Interleukin-6 (IL-6) and the phosphorylation pattern of signaling molecules of mitogen-activated protein kinase (MAPK) family, we performed ELISA and westren blot in Raw264.7 cells. In addition, nuclear factor-kappa B ($NF-{\kappa}B$) pathway was confirmed. PF extract inhibited the production of $TNF-{\alpha}$ and IL-6. The extract suppressed the phosphorylation of ERK1/2, JNK, and p38 MAPK, and the nuclear translocation of $NF-{\kappa}B$ p65 in activated cells. Our results suggest that PF can be used as a potential therapeutic agent or functional food to relieve inflammation.

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주요 한약재의 오존처리저장 특성 (Ozone Processing Storage Characteristic of Main Herb Medicines)

  • 우성훈;이광식
    • 조명전기설비학회논문지
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    • 제22권1호
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    • pp.66-72
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    • 2008
  • 최근 한약재의 저장 중 품질 유지를 위한 다양한 방안이 검토되고 있으며, 그 방안의 하나로 한약재의 유해 세균 및 잔존 농약을 분해, 처리하여 저장하는 방법을 연구하였다. 오존발생기에 관한 선행 연구를 통해 오존이 박테리아 및 비루스에 대한 살균효과가 우수함을 확인하고, 오존을 이용하여 한약재 살균처리 및 저장(이하 OPS)에 적용하는 방법을 연구하였다 본 연구에서는 현재 시중에 많이 유통되어 사용되고 있는 4종류의 약재를 선정하여 한약재 특성 평가를 실시하였다. 즉 오존 램프를 이용하여 한약재 살균 특성을 조사하였고, 장기간 오존 저장 후 한약재의 품질 및 고유 성분이 유지되는지를 조사하기 위하여 한약재의 일반성분 및 생리활성물질의 정량분석 평가를 하였다.

전북지역 도축돈 호흡기질병 조사 (Seasonal survey on the respiratory diseases of slaughtered pigs in Jeonbuk, Korea)

  • 임미나;김철민;박영민;송주태;진재권;조현웅
    • 한국동물위생학회지
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    • 제39권4호
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    • pp.231-237
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    • 2016
  • The present study was conducted to investigate the lesion of red internal organs in slaughtered pigs and provided assistant data for pig farms. During March to December 2015, a total of 1,160 lung samples out of 58 herds were collected randomly from pigs slaughtered in Jeonbuk province. In addition, 290 hilar lymph nodes from pig with pneumonic lung lesion (5 samples per herd) were screened for selected viral and bacterial pathogens. Gross lesions of lungs such as swine enzootic pneumonia (SEP), pleuritis, pleuropneumonia, pericarditis and liver white spots were examined. The overall prevalence of SEP was 64.3% (746/1,160). In the analysis of seasonal prevalence, there was an increase of occurrence during the spring months (287/400, 71.8%) and decrease during the fall months (93/200, 46.5%) among the whole herds. The mean number of SEP score per pig was $1.20{\pm}1.28$. The prevalence of pleuropneumonia, pleuritis, pericarditis, and milk spot was 25.5% (296/1,160), 44.1% (512/1,160), 3.8% (44/1,160) and 17.6% (204/1,160), respectively. The most frequent region with lung lesion was diaphragmatic lobes (left 17.1%, right 17.3%). In the detection of viral pathogens by PCR, porcine circovirus type2 (PCV2) was positive in 86.9% (252/290), while porcine reproductive and respiratory syndrome virus (PRRSV) was not detected, In the case of bacterial pathogens, 50 microorganisms were isolated by PCR and/or microbiological test. The most frequently isolated bacteria was Streptococcus suis (20, 34.4%), followed by Pasteurella multocida (17, 29.3%), Streptococcus spp. (11, 3.4%), Actinobacillus pleuropneumoniae (2, 8.9%).