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Antibacterial Mode of Action of Cinnamomum verum Bark Essential Oil, Alone and in Combination with Piperacillin, Against a Multi-Drug-Resistant Escherichia coli Strain

  • Yap, Polly Soo Xi;Krishnan, Thiba;Chan, Kok-Gan;Lim, Swee Hua Erin
    • Journal of Microbiology and Biotechnology
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    • v.25 no.8
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    • pp.1299-1306
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    • 2015
  • This study aims to investigate the mechanism of action of the cinnamon bark essential oil (CB), when used singly and also in combination with piperacillin, for its antimicrobial and synergistic activity against beta-lactamase TEM-1 plasmid-conferred Escherichia coli J53 R1. Viable count of bacteria for this combination of essential oil and antibiotic showed a complete killing profile at 20 h and further confirmed its synergistic effect by reducing the bacteria cell numbers. Analysis on the stability of treated cultures for cell membrane permeability by CB when tested against sodium dodecyl sulfate revealed that the bacterial cell membrane was disrupted by the essential oil. Scanning electron microscopy observation and bacterial surface charge measurement also revealed that CB causes irreversible membrane damage and reduces the bacterial surface charge. In addition, bioluminescence expression of Escherichia coli [pSB1075] and E. coli [pSB401] by CB showed reduction, indicating the possibility of the presence of quorum sensing (QS) inhibitors. Gas-chromatography and mass spectrometry of the essential oil of Cinnamomum verum showed that trans-cinnamaldehyde (72.81%), benzyl alcohol (12.5%), and eugenol (6.57%) were the major components in the essential oil. From this study, CB has the potential to reverse E. coli J53 R1 resistance to piperacillin through two pathways; modification in the permeability of the outer membrane or bacterial QS inhibition.

Comparison of two different methods of detecting residual caries

  • Vural, Uzay Koc;Kutuk, Zeynep Bilge;Ergin, Esra;Cakir, Filiz Yalcin;Gurgan, Sevil
    • Restorative Dentistry and Endodontics
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    • v.42 no.1
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    • pp.48-53
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    • 2017
  • Objectives: The aim of this study was to investigate the ability of the fluorescence-aided caries excavation (FACE) device to detect residual caries by comparing conventional methods in vivo. Materials and Methods: A total of 301 females and 202 males with carious teeth participated in this study. The cavity preparations were done by grade 4 (Group 1, 154 teeth), grade 5 (Group 2, 176 teeth), and postgraduate (Group 3, 173 teeth) students. After caries excavation using a handpiece and hand instruments, the presence of residual caries was evaluated by 2 investigators who were previously calibrated for visual-tactile assessment with and without magnifying glasses and trained in the use of a FACE device. The tooth number, cavity type, and presence or absence of residual caries were recorded. The data were analyzed using the Chi-square test, the Fisher's Exact test, or the McNemar test as appropriate. Kappa statistics was used for calibration. In all tests, the level of significance was set at p = 0.05. Results: Almost half of the cavities prepared were Class II (Class I, 20.9%; Class II, 48.9%; Class III, 20.1%; Class IV, 3.4%; Class V, 6.8%). Higher numbers of cavities left with caries were observed in Groups 1 and 2 than in Group 3 for all examination methods. Significant differences were found between visual inspection with or without magnifying glasses and inspection with a FACE device for all groups (p < 0.001). More residual caries were detected through inspection with a FACE device (46.5%) than through either visual inspection (31.8%) or inspection with a magnifying glass (37.6%). Conclusions: Within the limitations of this study, the FACE device may be an effective method for the detection of residual caries.

How to Improve Eating Behaviour during Early Childhood

  • Green, Robin John;Samy, Gamal;Miqdady, Mohamad Saleh;Salah, Mohamed;Sleiman, Rola;Abdelrahman, Hatim Mohamed Ahmed;Al Haddad, Fatima;Reda, Mona M.;Lewis, Humphrey;Ekanem, Emmanuel E.;Vandenplas, Yvan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.18 no.1
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    • pp.1-9
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    • 2015
  • Eating behaviour disorder during early childhood is a common pediatric problem. Many terminologies have been used interchangeably to describe this condition, hindering implementation of therapy and confusing a common problem. The definition suggests an eating behaviour which has consequences for family harmony and growth. The recent Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition does not cover the entire spectrum seen by pediatricians. Publications are substantive but level of evidence is most of the time low. This purpose of this review is to clarify terminology of eating behaviour problems during early childhood; including benign picky eating, limited diets, sensory food aversion, selective eating, food avoidance emotional disorder, pervasive refusal syndrome, tactile defensiveness, functional dysphagia, neophobia and toddler anorexia. This tool is proposed only to ease the clinical management for child care providers. Diagnostic criteria are set and management tools are suggested. The role of dietary counselling and, where necessary, behavioural therapy is clarified. It is hoped that the condition will make its way into mainstream pediatrics to allow these children, and their families, to receive the help they deserve.

Prediction of Baltic Dry Index by Applications of Long Short-Term Memory (Long Short-Term Memory를 활용한 건화물운임지수 예측)

  • HAN, Minsoo;YU, Song-Jin
    • Journal of Korean Society for Quality Management
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    • v.47 no.3
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    • pp.497-508
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    • 2019
  • Purpose: The purpose of this study is to overcome limitations of conventional studies that to predict Baltic Dry Index (BDI). The study proposed applications of Artificial Neural Network (ANN) named Long Short-Term Memory (LSTM) to predict BDI. Methods: The BDI time-series prediction was carried out through eight variables related to the dry bulk market. The prediction was conducted in two steps. First, identifying the goodness of fitness for the BDI time-series of specific ANN models and determining the network structures to be used in the next step. While using ANN's generalization capability, the structures determined in the previous steps were used in the empirical prediction step, and the sliding-window method was applied to make a daily (one-day ahead) prediction. Results: At the empirical prediction step, it was possible to predict variable y(BDI time series) at point of time t by 8 variables (related to the dry bulk market) of x at point of time (t-1). LSTM, known to be good at learning over a long period of time, showed the best performance with higher predictive accuracy compared to Multi-Layer Perceptron (MLP) and Recurrent Neural Network (RNN). Conclusion: Applying this study to real business would require long-term predictions by applying more detailed forecasting techniques. I hope that the research can provide a point of reference in the dry bulk market, and furthermore in the decision-making and investment in the future of the shipping business as a whole.

Monitoring Compliance and Examining Challenges of a Smoke-free Policy in Jayapura, Indonesia

  • Wahyuti, Wahyuti;Hasairin, Suci K.;Mamoribo, Sherly N.;Ahsan, Abdillah;Kusuma, Dian
    • Journal of Preventive Medicine and Public Health
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    • v.52 no.6
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    • pp.427-432
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    • 2019
  • Objectives: In Indonesia, 61 million adults smoked in 2018, and 59 million were exposed to secondhand smoke at offices or restaurants in 2011. The Presidential Decree 109/2012 encouraged local governments to implement a smoke-free policy (SFP), and the city of Jayapura enacted a local bill (1/2015) to that effect in 2015. This study aimed to evaluate compliance with this bill and to explore challenges in implementing it. Methods: We conducted a mixed-methods study. Quantitatively, we assessed compliance of facilities with 6 criteria (per the bill): the presence of signage, the lack of smoking activity, the lack of sale of tobacco, the lack of tobacco advertisements, the lack of cigarette smoke, and the lack of ashtrays. We surveyed 192 facilities, including health facilities, educational facilities, places of worship, government offices, and indoor and outdoor public facilities. Qualitatively, we explored challenges in implementation by interviewing 19 informants (government officers, students, and community members). Results: The rate of compliance with all 6 criteria was 17% overall, ranging from 0% at outdoor public facilities to 50% at health facilities. Spatial patterning was absent, as shown by similar compliance rates for SFP facilities within a 1-km boundary around the provincial and city health offices compared to those outside the boundary. Implementation challenges included (1) a limited budget for enforcement, (2) a lack of support from local non-governmental organizations and universities, (3) a lack of public awareness at the facilities themselves, and (4) a lack of examples set by local leaders. Conclusions: Overall compliance was low in Jayapura due to many challenges. This information provides lessons regarding tobacco control policy in underdeveloped areas far from the central government.

Comparison of the effects of horizontal and vertical micro-osteoperforations on the biological response and tooth movement in rabbits

  • Kim, Seok-gon;Kook, Yoon-Ah;Lim, Hee Jin;Park, Patrick;Lee, Won;Park, Jae Hyun;Bayome, Mohamed;Kim, Yoonji
    • The korean journal of orthodontics
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    • v.51 no.5
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    • pp.304-312
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    • 2021
  • Objective: This study aimed to compare the amount of tooth movement after multiple horizontal (MH) and single vertical (SV) micro-osteoperforations (MOPs), and evaluate the histological changes after orthodontic force application in rabbits. Methods: The mandibles of 24 white rabbits were subjected to two experimental interventions: MH and SV MOPs. Defect volume of the MOPs between the two groups was kept similar. A force of 100 cN was applied via a coil spring between the incisor teeth and the first premolars. The amount of tooth movement was measured. Differences in the amount of tooth movement and bone variables at three time points and between the two groups were evaluated using repeated-measures analysis of variance. Results: The first premolar showed a mesial movement of 1.47 mm in the MH group and 1.84 mm in the SV group, which was significantly different at Week 3 (p < 0.05). No significant difference was observed in bone volume and bone fraction between the groups. Tartrate-resistant acidic phosphatase-positive cell count was also significantly greater at Week 3 than at Week 1 in both the SV and MH groups. Conclusions: The amount of tooth movement showed significant differences between Weeks 1 and 3 in the SV and MH MOP groups, but showed no differences between the two groups. Therefore, SV MOP could be considered an effective tool for enhancing tooth movement, especially for molar distalization, uprighting, and protraction to an edentulous area.

Tuber quality of Ashwagandha (Withania somnifera Duanal) affected by different growth conditions

  • Kaliyadasa, Ewon;Jayasinghe, Lalith;Peiris, Sriyani
    • Korean Journal of Agricultural Science
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    • v.46 no.1
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    • pp.151-161
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    • 2019
  • Ashwagandha (Withania sominifera Duanal) is an important medicinal herb with increased demand after discovering its anti-stress and sex stimulating properties that are attributed to the presence of biologically active alkaloid compounds. The aim of this study was to elucidate a proper agro technological package that ensures the optimum growth of Ashwagandha to obtain the finest quality without degrading the pharmacologically active constituents. Mixtures of organic and inorganic fertilizers were combined with direct seeding and transplanted as four different treatments in this study. The fresh and dry weights of the tubers were recorded up to 12 months starting from two months after sowing (MAS) while the shoot height, root length, number of leaves, fresh and dry weights of the shoot and the root with a shoot ratio of up to 6 MAS were determined. The results revealed that the growth of Ashwagandha was not affected significantly by the method of planting, type of fertilizer or their combinations during most of the harvests. However, tubers harvested at 6 MAS had the highest recorded dry tuber weight per plant in all four treatments compared to the early harvests where two direct seeded treatments had the best results. Comparison of the phytochemical compounds showed that direct seeding with organic fertilizer had the highest recorded values for alkaloid and withaferine A contents with a lower percentage of fiber compared to the treatments with inorganic fertilizer. In conclusion, direct seeding with organic fertilizer and tubers harvested at 6 MAS are recommended as the best cultivation conditions and harvesting stage to obtain high quality tubers of Ashwagandha, respectively.

Exploring the Study Experiences of Southeast Asian Students at a Korean University in Seoul (서울 A대학 동남아시아 유학생의 학업 경험에 대한 탐색적 연구)

  • KIM, Jeehun
    • The Southeast Asian review
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    • v.23 no.3
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    • pp.135-179
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    • 2013
  • This study explores the study experiences of Southeast Asian students at a reputable Korean private university in Seoul. In particular, this study focuses on difficulties and coping strategies of both non-native speaker of English and native-speakers of English who are working for their undergraduate or postgraduate degrees. Interviews of fourteen students from five Southeast Asian countries were collected and analyzed by NVivo 9. Thematic analysis result shows that many students, particularly non-native speakers of English, had much more difficulties than their counterparts, in contemporary Korean university context, where internationalization indices-driven strategies including expanding courses conducted in English language. Also, this study observes and documents contrasting patterns of different degree of difficulties experienced by students, depending on their degree levels and majors. Undergraduate students in science and engineering majors had the greatest degree of difficulties among all. In contrast, their graduate counterparts seem to have less difficulties. This might be related to the fact that graduate students in science and engineering majors are mostly working with their peers in their own labs, which provides institutional support. Coping strategies of students show that international students, facing unfavorable or unfriendly treatments by their Korean peers, developed innovative strategies, including using the internet technology to catch up with the classes that they could not fully understand. As a whole, adaptation process of international students do not seem to be passive or one-way. This study also provides policy implications for international students, particularly, who can be categorized as linguistic and ethnic minorities.

Bio-hybrid dental implants prepared using stem cells with β-TCP-coated titanium and zirconia

  • Safi, Ihab Nabeel;Hussein, Basima Mohammed Ali;Al-Shammari, Ahmed Majeed
    • Journal of Periodontal and Implant Science
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    • v.52 no.3
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    • pp.242-257
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    • 2022
  • Purpose: This study investigated periodontal ligament (PDL) restoration in osseointegrated implants using stem cells. Methods: Commercial pure titanium and zirconium oxide (zirconia) were coated with beta-tricalcium phosphate (β-TCP) using a long-pulse Nd:YAG laser (1,064 nm). Isolated bone marrow mesenchymal cells (BMMSCs) from rabbit tibia and femur, isolated PDL stem cells (PDLSCs) from the lower right incisor, and co-cultured BMMSCs and PDLSCs were tested for periostin markers using an immunofluorescent assay. Implants with 3D-engineered tissue were implanted into the lower right central incisors after extraction from rabbits. Forty implants (Ti or zirconia) were subdivided according to the duration of implantation (healing period: 45 or 90 days). Each subgroup (20 implants) was subdivided into 4 groups (without cells, PDLSC sheets, BMMSC sheets, and co-culture cell sheets). All groups underwent histological testing involving haematoxylin and eosin staining and immunohistochemistry, stereoscopic analysis to measure the PDL width, and field emission scanning electron microscopy (FESEM). The natural lower central incisors were used as controls. Results: The BMMSCs co-cultured with PDLSCs generated a well-formed PDL tissue that exhibited positive periostin expression. Histological analysis showed that the implantation of coated (Ti and zirconia) dental implants without a cell sheet resulted in a well-osseointegrated implant at both healing intervals, which was confirmed with FESEM analysis and negative periostin expression. The mesenchymal tissue structured from PDLSCs only or co-cultured (BMMSCs and PDLSCs) could form a natural periodontal tissue with no significant difference between Ti and zirconia implants, consequently forming a biohybrid dental implant. Green fluorescence for periostin was clearly detected around the biohybrid implants after 45 and 90 days. FESEM showed the invasion of PDL-like fibres perpendicular to the cementum of the bio-hybrid implants. Conclusions: β-TCP-coated (Ti and zirconia) implants generated periodontal tissue and formed biohybrid implants when mesenchymal-tissue-layered cell sheets were isolated from PDLSCs alone or co-cultured BMMSCs and PDLSCs.

Examining the Practice of Digital Scholarship Services at Vietnam National University Ho Chi Minh City

  • Ngo, Thi Huyen;Nguyen, Hong Sinh;Ninh, Thi Kim Thoa
    • Journal of Information Science Theory and Practice
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    • v.10 no.1
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    • pp.1-17
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    • 2022
  • The article reports the results of an investigation on the practice of providing digital scholarship services at Vietnam National University Ho Chi Minh City, Vietnam. This study is part of an ongoing research project entitled Developing a digital scholarship service framework for universities at Vietnam National University Ho Chi Minh City. It employed a qualitative research approach through in-depth interviews with 31 individuals who are university managers, library managers, lecturers, and postgraduate and undergraduate students from six member universities and Central Library of Vietnam National University Ho Chi Minh City. Research results show that some digital scholarship services have been provided at Vietnam National University Ho Chi Minh City. However, they have not been yet systematically implemented and have not met users' needs. Lack of needed resources such as space, technology infrastructure, human resources, finance, and stakeholder support are among major challenges in developing digital scholarship services. The management of existing digital scholarship services is fragmented without a clear policy for developing digital scholarship and supporting services. The study contributes to the existing knowledge by adding substantially to current understanding of the practice of providing digital scholarship services in Vietnam's universities in the transition period, from state control to autonomy, which has not been much addressed in previous research. Furthermore, this study can be a useful reference for higher education institutions in developing countries regarding implementation of digital scholarship services.