• Advances in environmental research
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• 제5권3호
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• pp.201-211
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• 2016

Laboratory tests were conducted to evaluate the performance of waste rubber shreds in leachate collection layer of engineered landfills. The study found that waste rubber shreds layer in combination with a gravel layer can be of potential use in landfill drainage system. To study the performance, conventional gravel along with waste rubber shreds were used in different combinations (with total layer thickness = 500 mm) as leachate collection media. For the laboratory study poly vinyl chloride (PVC) pipes were used. The size range of waste rubber shreds used were 25 mm to 75 mm in length and width = 10 to 20 mm. The gravel size used in the leachate collection media is 10 mm to 20 mm size. Performance study of 7 Test Cols. with different combinations of waste rubber shreds and gravel bed thickness were studied to find out the best combination. The study found that the Test Col.-3 having waste rubber shreds thickness = 200 mm and gravel layer thickness = 300 mm gave the best results in terms of percentage removal in various physicochemical parameters present in the leachate. Further to find the best size rubber shreds three more Test Cols - 8, 9 and 10 were constructed having the rubber shreds and gravel layer ratio same as that of Test Col.-3 but having rubber shreds width = 10 mm, 15 mm and 20 mm respectively. Based on the results obtained using Test Cols. 8, 9 and 10 the study found that smaller size rubber shreds gave bests results in terms of improvement in various leachate parameters.

• Advances in environmental research
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• 제10권1호
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• pp.43-57
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• 2021

Evaluation of groundwater quality is vital due to its diverse use for several purposes. In the present study, groundwater quality and suitability from the Peshawar basin, Pakistan, were evaluated for drinking and irrigation purposes. The water samples were analysed for major cations (Ca, Mg, Na and K) and anions (chloride, bicarbonate and sulphate) along with other physicochemical parameters (pH, electrical conductivity, total dissolved solids, and total hardness). About 95% of the water samples were found to be within the WHO, US-EPA and Pak-EPA permissible levels for drinking purposes. Seventy percent (70%) of the water samples belonged to the hard water category. Irrigation water quality parameters, such as, chloride, residual sodium bicarbonate, sodium adsorption ratio, percent sodium, magnesium adsorption ratio, Kelly's ration and permeability index were evaluated which demonstrated that the groundwater was highly to moderately suitable for irrigation. A correlation study was conducted to find out the mutual associations among the variables. Piper diagram indicated the overall chemical nature of the study area was calcium-magnesium bicarbonate type. Cluster analysis revealed mutual apportionment of various parameters in the groundwater of the Peshawar basin, Pakistan.

• Animal Bioscience
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• 제36권6호
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• pp.953-961
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• 2023

Objective: This study aimed to investigate the effect of dorsal cranial myopathy (DCM) on chicken meat quality. Methods: Sixty-six Ross 308 AP broilers, 47 days old, of both sexes, weighing about 3.51 kg, were slaughtered according to standard industrial practices, and evaluated for meat color, pH, chemical composition, collagen content, fatty acid profile, and histopathological parameters. Comparisons between normal and DCM-affected meat were performed using Student's t-test at the 5% significance level. Results: Histological analysis of muscle tissues affected by DCM showed myofiber degeneration, proliferation of inflammatory cells, fibroplasia, and necrosis with fibrosis. DCM samples had lower protein content and higher moisture, ash, insoluble collagen, total collagen, and pH. DCM-affected meat was redder and more yellowish. There were no differences in lipid or soluble collagen contents between groups. DCM-affected meat had higher percentages of arachidonic acid (C20:4n-6) and eicosapentaenoic acid (C20:5n-3). Conclusion: This study revealed that DCM-affected meat exhibits considerable changes in quality parameters.

• 한국산업보건학회지
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• 제29권3호
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• pp.358-367
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• 2019

Objectives: This study aimed to review model algorithms and input parameters applied to some exposure models and to compare the simulated estimates using an exposure scenario from each model. Methods: A total of five exposure models which can estimate inhalation exposure were selected; the Korea Ministry of Environment(KMOE) exposure model, European Centre for Ecotoxicology and Toxicology of Chemicals Targeted Risk Assessment(ECETOC TRA), SprayExpo, and ConsExpo model. Algorithms and input parameters for exposure estimation were reviewed and the exposure scenario was used for comparing the modeled estimates. Results: Algorithms in each model commonly consist of the function combining physicochemical properties, use characteristics, user exposure factors, and environmental factors. The outputs including air concentration ($mg/m^3$) and inhaled dose(mg/kg/day) are estimated applying input parameters with the common factors to the algorithm. In particular, the input parameters needed to estimate are complicated among the models and models need more individual input parameters in addition to common factors. In case of CEM, it can be obtained more detailed exposure estimates separating user's breathing zone(near-field) and those at influencing zone(far-field) by two-box model. The modeled exposure estimates using the exposure scenario were similar between the models; they were ranged from 0.82 to $1.38mg/m^3$ for concentration and from 0.015 to 0.180 mg/kg/day for inhaled dose, respectively. Conclusions: Modeling technique can be used for a useful tool in the process of exposure assessment if the exposure data are scarce, but it is necessary to consider proper input parameters and exposure scenario which can affect the real exposure conditions.

• 한국지역사회생활과학회지
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• 제16권4호
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• pp.3-13
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• 2005

본 실험은 야산에서 재배한 더덕의 장기 저장을 목적으로 포장재와 온도를 달리하여 30일간 저장하면서 pH, 수분, 회분, 일부 무기성분과 사포닌의 함량 변화를 조사하였다. 신선한 더거 즙액의 pH는 5.3이었고 30일에는 $4.2{\∼}4.3$으로 유의적으로 감소하였다. 수분함량은 저장 온도보다는 포장재질에 의해 영향 받는 정도가 컸다. 회분함량은 저장기간이 증가할수록 크게 감소하여, 30일 후에는 신선더덕의 $14{\∼}67\%$만을 함유하고 있었다. 더덕의 무기성분 함량은 종류에 따라 정도는 다르지만 저장기일이 증가함에 따라 감소하였으며, 이는 더덕의 pH와 회분함량의 변화와 관련이 있을 것으로 여겨진다. 저장 기간이 증가함에 따라 더덕 즙액의 색탁은 약간 어두어졌고, 15일 저장 시 약간 붉은 색을 띠는 경향이 뚜렷했으나 점차 감소하였으며, 황색도는 저장조건별로 변화 양상이 달랐다. 조사포닌 함량은 1g당 29.7mg이었고, 30일간 저장 시 항균포장을 하거나 냉장 저장을 한 경우에는 초기 함량과 유의적 차이가 없었으나 마대포장-실온저장 더덕은 30일간 저장 시 24.9mg으로 유의적으로 감소하였다. Codonoposide 함량은 건조 더덕 100g 중 382mg으로, 조사포닌 총량의 약 $8\%$였으며, 15일 저장 시 마대포장-실온저장 더덕은 약간 증가한 반면, 나머지 조건에서는 감소하였고, 30일 저장 시에는 $304{\∼}365mg$으로 초기 시료보다 낮아져, 전반적으로는 감소 경향을 보였으나 모든 저장조건에서 유의적인 변화는 아니었다. 이상의 결과로 미루어 야산에서 재배된 더덕의 장기 저장 조건은 항균포장-냉장저장인 것으로 보인다.

• 한국식품과학회지
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• 제34권6호
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• pp.1007-1012
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• 2002

도토리의 해충방제를 위한 감마선 조사가 도토리에서 추출한 전분의 이화학적 및 관능적 특성에 미치는 영향을 검토하였다. 전분의 기계적 색도(Hunter L, a, b)는 $0.25{\sim}10\;kGy$ 범위에서 변화되지 않았다. 살충선량인 1 kGy의 감마선 조사는 전분입자의 형태에 변화를 초래하지 않았으나 10 kGy에서는 입자표면의 손상이 관찰되었다. X-선 회절분석에서 회절양상은 전분입자의 무정형 부분이나 결정성 영역에 있어서 처리구간에 차이가 나타나지 않았다. 물결합력, 팽윤력, 용해도, 호화양상 등은 감마선 조사건량의 증가로 변화를 보였으며, $0.5{\sim}1\;kGy$ 범위에서는 전분의 이화학적 특성에 거의 영향이 없었다. 한편 도토리전분 겔을 제조하여 처리선량별 텍스쳐를 측정해 본 결과, 전반적인 물성 인자들은 1 kGy 선량 이하에서는 변화가 크지 않았으나 3 kGy 이상 조사구에서는 경도, 점착성,씹힘성 등에 있어서 변화가 심하였다. 이상의 결과에서 1 kGy 이하의 감마선 조사는 도토리 전분의 이화학적 특성과 가공적성에 유의적인 변화를 주지 않으면서 도토리의 해충을 사멸할 수 있을 것으로 기대된다.

• 생태와환경
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• 제33권4호통권92호
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• pp.358-365
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• 2000

백련어의 도입 및 제거가 부영양호의 수중생물군집과 환경요인에 미치는 영향을 조사하였다. 생물조작을 위해 호수연안에 6개의 enclosure를 설치하고, 5월 22일부터 7월 23일까지(전기), 7월 23일부터 9월 18일까지(후기) 두 가지 밀도(고, 저)의 어류를 투입 및 제거하였다. RIA(${\alpha}$=0.05)의 결과는 어류도입 및 제거가 대부분의 생물군집 및 환경요인에 유의한 영향을 미치는 것으로 나타났다. 각 enclosure의 환경요인에 대해 어류투입은 투명도, 용존산소, 수소이온농도, 큰분획엽록소(>40 ${\mu}$m) 등의 감소와 질소화합물, 소형분획엽록소(<2 ${\mu}$m)의 증가를 유도하였으며, 어류제거는 정반대 현상을 보였다. 한편, 수중생물군집에 있어서, 어류투입은 picocyanobacteria이나 섬모충(<20 ${\mu}$m) 같은 소형 플랑크톤의 증가가 뚜렷하였고, 어류제거에 의해 다시 유의하게 회복하였다. 그러나 크고, 군체를 형성하거나 긴 사상체 남조나 규조등은 두 가지 어류조작에 유의한 변화를 보이지 않았으며, 어류제거시만 Diaphanosoma, Cyclopoida, naupli 등 동물플랑크톤의 유의한 증가를 나타냈다. 본 연구는 실험기간 동안 강한 바람과 호수바닥으로부터 지속적인 인의 공급 등으로 인하여 결과해석에 부정적으로 작용하였으나, 전체적으로 어류도입 및 제거가 enclosure내 플랑크톤군집과 환경요인에 대해 서로 상반되는 효과를 유도하는 것이 확인되었다.

• Membrane and Water Treatment
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• 제10권1호
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• pp.29-38
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• 2019

Microbial community and composition in stormwater runoff from mixed land use land cover (LULC) catchment with ongoing land development was diverse across the hydrological stage due different environmental parameters (hydrometeorological and physicochemical) and source of runoff. However, limited studies have been made for bacterial composition in this catchment. Therefore, this study aims to: (1) quantify the concentration of fecal indicator bacteria (FIB), stormwater quality and bacterial composition and structure according to hydrological stage; and (2) determine their correlation to environmental parameters. The 454 pyrosequencing was used to determine the bacterial community and composition; while Pearson's correlation was used to determine the correlation among parameters-FIB, stormwater quality, bacterial composition and structure-to environmental parameters. Results demonstrated that the initial and peak runoff has the highest concentration of FIB, stormwater quality and bacterial composition and structure. Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes were dominant bacteria identified in this catchment. Furthermore, the 20 most abundant genera were correlated with runoff duration, average rainfall intensity, runoff volume, runoff flow, temperature, pH, organic matter, nutrients, TSS and turbidity. An increase of FIB and stormwater quality concentration, diversity and richness of bacterial composition and structure in this study was possibly due to leakage from septic tanks, cesspools and latrines; feces of domestic and wild animals; and runoff from forest, destroyed septic system in land development site and urban LULC. Overall, this study will provide an evidence of hydrological stage impacts on the runoff microbiome environment and public health perspective.

• Environmental Engineering Research
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• 제20권3호
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• pp.254-259
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• 2015

In this study, the characteristics as well as the maturity and stability of chicken manure collected from nine chicken farms in South Korea during the summer and winter seasons of 2014 are evaluated. The physicochemical parameter values of the manure, such as BOD, $NO_3-N$ and $PO_4-P$ etc. were determined using the Korea Standard test Method, HPLC, and APHA standard methods. The results showed that the alkalinity content and COD concentration in winter chicken manure were higher than those of summer chicken manure. The moisture content of summer manure was positively correlated with almost all of the other parameters of the manure, whereas it was negatively correlated with almost all of the other parameters in the winter manure. According to the criterion of C/N ratio, chicken manure indicated good quality compost. However, composted chicken manure showed immature and unstable compost when considering the criteria of the $NH_4-N/NO_3-N$ ratio and $NH_4-N$ concentrations.

• Genomics & Informatics
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• 제21권2호
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• pp.21.1-21.14
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• 2023

Fusobacterium nucleatum is a gram-negative bacteria associated with diverse infections like appendicitis and colorectal cancer. It mainly attacks the epithelial cells in the oral cavity and throat of the infected individual. It has a single circular genome of 2.7 Mb. Many proteins in F. nucleatum genome are listed as "Uncharacterized." Annotation of these proteins is crucial for obtaining new facts about the pathogen and deciphering the gene regulation, functions, and pathways along with discovery of novel target proteins. In the light of new genomic information, an armoury of bioinformatic tools were used for predicting the physicochemical parameters, domain and motif search, pattern search, and localization of the uncharacterized proteins. The programs such as receiver operating characteristics determine the efficacy of the databases that have been employed for prediction of different parameters at 83.6%. Functions were successfully assigned to 46 uncharacterized proteins which included enzymes, transporter proteins, membrane proteins, binding proteins, etc. Apart from the function prediction, the proteins were also subjected to string analysis to reveal the interacting partners. The annotated proteins were also put through homology-based structure prediction and modeling using Swiss PDB and Phyre2 servers. Two probable virulent factors were also identified which could be investigated further for potential drug-related studies. The assigning of functions to uncharacterized proteins has shown that some of these proteins are important for cell survival inside the host and can act as effective drug targets.