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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.

Modern Possibilities and Prospects of Nanotechnology in Dentistry

  • Sergiy, Chertov;Valery, Kaminskyy;Olha, Tatarina;Oleksii, Mandych;Andrii, Oliinyk
    • International Journal of Computer Science & Network Security
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    • v.22 no.10
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    • pp.97-106
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    • 2022
  • Objective. Nanotechnology is spreading among all areas of life, from everyday devices to medicine. The concept of nanotechnology argues that not only can new physical and chemical properties of materials be discovered, but also the new potential of nanostructures when reduced to the nanoscale. The growing interest in the application of nanomaterials in dentistry contributes to the proliferation of the range of nanomaterials used by specialists. The purpose of this review of information sources was to analyze the prospects for the use of nanomaterials in dentistry. Methods. We used the bibliographic semantic method of research, for which we analyzed electronic databases of primary literature sources Scopus, Web of Science, Research Gate, PubMed, MDPI, and MedLine. English-language scientific articles published after 2017 were taken into consideration. Results. According to the results of a search study among modern information primary sources, nanotechnology improves the preventive properties of oral care products, improves the structural-mechanical and aesthetic properties of composite mixtures for dentistry, overcomes the problems of the clinical application of dental implants. Despite the prospects of nanotechnology applications in medicine in general and dentistry in particular, the existing economic and technological problems require a thorough solution for further implementation of nanostructures. Scientific novelty. For the first time, the analysis of modern trends in the application of nanotechnology in dentistry is carried out and the peculiarities of materials are highlighted, the problems and prospects of nanostructures implementation in modern dental implantology are given, physical, chemical, mechanical, and antibacterial properties of nanomaterials are evaluated. The effect of nanomaterials on the microbial adhesion of the tooth or implant surface is described. Practical significance. The presented publication can become a scientific basis for the solution of urgent problems hindering the introduction of nanotechnology into dental practice. Conclusions. Thus, the use of nanostructures opens up great opportunities for the treatment of a wide range of diseases, not only of dental nature but also in medicine in general.

Impaired Health-Related Quality of Life in Brazilian Children with Chronic Abdominal Pain: A Cross-Sectional Study

  • Jesus, Carine Dias Ferreira de;Carvalho, Mary de Assis;Machado, Nilton Carlos
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.25 no.6
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    • pp.500-509
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    • 2022
  • Purpose: We compared the health-related quality of life (HRQOL) of children and adolescents with functional abdominal pain disorders (FAPDs) and organic abdominal pain disorders (ORGDs). Methods: This was a single-center, cross-sectional, observational study. The PedsQL 4.0 generic cores scales parent proxy-report was administered to parents/caregivers of 130 and 56 pediatric patients with FAPDs and ORGDs respectively on their first visit. The self-reported pain intensity in the patients was assessed using a visual analog scale (VAS) and facial affective scale (FAS). Results: Irritable bowel syndrome was the most prevalent FAPDs, and the most prevalent ORGDs were reflux esophagitis (41.1%) and gastritis associated with Helicobacter pylori (21.4%). There was no difference in HRQOL among patients diagnosed with ORGDs and FAPDs (p>0.05). Patients with ORGDs and FAPDs had lower HRQOL Scale scores than healthy Brazilian and American children's references, with a high proportion of children at risk for impaired HRQOL (p<0.0001). There was no difference in the VAS and the FAS scores between the ORGDs and the FAPDs. FAPDs had a higher prevalence of girls' and couples' disagreement (p<0.02), although poor school performance (p<0.0007) and bullying (p<0.01) were higher in patients with ORGD. Conclusion: This study revealed that there was a difference in impaired HRQOL between patients with ORGDs and FAPDs. Thus, considering the high prevalence of chronic abdominal pain in children, a well-founded treatment plan is necessary for a multidisciplinary cognitive-behavioral Pain management program.

Cone-beam computed tomography texture analysis can help differentiate odontogenic and non-odontogenic maxillary sinusitis

  • Andre Luiz Ferreira Costa;Karolina Aparecida Castilho Fardim;Isabela Teixeira Ribeiro;Maria Aparecida Neves Jardini;Paulo Henrique Braz-Silva;Kaan Orhan;Sergio Lucio Pereira de Castro Lopes
    • Imaging Science in Dentistry
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    • v.53 no.1
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    • pp.43-51
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    • 2023
  • Purpose: This study aimed to assess texture analysis(TA) of cone-beam computed tomography (CBCT) images as a quantitative tool for the differential diagnosis of odontogenic and non-odontogenic maxillary sinusitis(OS and NOS, respectively). Materials and Methods: CBCT images of 40 patients diagnosed with OS (N=20) and NOS (N=20) were evaluated. The gray level co-occurrence (GLCM) matrix parameters, and gray level run length matrix texture (GLRLM) parameters were extracted using manually placed regions of interest on lesion images. Seven texture parameters were calculated using GLCM and 4 parameters using GLRLM. The Mann-Whitney test was used for comparisons between the groups, and the Levene test was performed to confirm the homogeneity of variance (α=5%). Results: The results showed statistically significant differences(P<0.05) between the OS and NOS patients regarding 3 TA parameters. NOS patients presented higher values for contrast, while OS patients presented higher values for correlation and inverse difference moment. Greater textural homogeneity was observed in the OS patients than in the NOS patients, with statistically significant differences in standard deviations between the groups for correlation, sum of squares, sum of entropy, and entropy. Conclusion: TA enabled quantitative differentiation between OS and NOS on CBCT images by using the parameters of contrast, correlation, and inverse difference moment.

Texture analysis in cone-beam computed tomographic images of medication-related osteonecrosis of the jaw

  • Polyane Mazucatto Queiroz;Karolina Castilho Fardim;Andre Luiz Ferreira Costa;Ricardo Alves Matheus;Sergio Lucio Pereira Castro Lopes
    • Imaging Science in Dentistry
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    • v.53 no.2
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    • pp.109-115
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    • 2023
  • Purpose: The aim of this study was to evaluate changes in the trabecular bone through texture analysis and compare the texture analysis characteristics of different areas in patients with medication-related osteonecrosis of the jaw (MRONJ). Materials and Methods: Cone-beam computed tomographic images of 16 patients diagnosed with MRONJ were used. In sagittal images, 3 regions were chosen: active osteonecrosis(AO); intermediate tissue (IT), which presented a zone of apparently healthy tissue adjacent to the AO area; and healthy bone tissue (HT) (control area). Texture analysis was performed evaluating 7 parameters: secondary angular momentum, contrast, correlation, sum of squares, inverse moment of difference, sum of entropies, and entropy. Data were analyzed using the Kruskal-Wallis test with a significance level of 5%. Results: Comparing the areas of AO, IT, and HT, significant differences (P<0.05) were observed. The IT and AO area images showed higher values for parameters such as contrast, entropy, and secondary angular momentum than the HT area, indicating greater disorder in these tissues. Conclusion: Through texture analysis, changes in the bone pattern could be observed in areas of osteonecrosis. The texture analysis demonstrated that areas visually identified and classified as IT still had necrotic tissue, thereby increasing the accuracy of delimiting the real extension of MRONJ.

Development of an Evaluation Tool Model for Cybersickness Measurement of Immersive Virtual Reality (몰입형 가상현실 사이버 멀미 측정을 위한 평가 도구 모델 개발)

  • Choi, Chang-Min;Jung, Hyeon-Won
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.5
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    • pp.59-65
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    • 2019
  • The decline of cybersickness, an important task that must be addressed in terms of growth of the virtual reality content industry, is a subject of much attention not only in the industrial sector but also in academia. However, despite the long-standing interest in and research on cybersickness, the solution is insufficient. In this paper, the purpose of this paper is to develop a tool to effectively measure cybersickness when users experience immersive virtual reality, and come up with measures to reduce cybersickness. First, the common factors related to cybersickness were analyzed in the method used in the preceding study, and each was derived as a subcomponent. Based on this, we are going to present an effective cybersickness measurement assessment tool model in immersive virtual reality. We would like to refer the assessment tool model to the study as well as to the reduction of cybersickness.

Pathologic conditions associated with impacted third molars: A retrospective study of panoramic radiographs in a Southern Brazilian population

  • Gabriela Brum Cardoso;Gleica Dal' Ongaro Savegnago;Waneza Dias Borges Hirsch;Mariana Boessio Vizzotto;Gabriela Salatino Liedke
    • Imaging Science in Dentistry
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    • v.53 no.4
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    • pp.303-312
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    • 2023
  • Purpose: This study investigated the prevalence of developmental and acquired pathologic conditions associated with impacted third molars (3Ms) in a Southern Brazilian population and evaluated whether demographic and tooth characteristics were correlated with the presence of bone or tooth lesions. Materials and Methods: Panoramic radiographs were assessed for developmental (bone-related) or acquired (tooth-related) pathoses associated with impacted upper or lower 3Ms. Data on tooth positioning, tooth development, and patient demographics were collected. A trained, calibrated postgraduate student evaluated all images. Binary and multivariate logistic regression models were used to assess associations between outcomes and the demographic and radiographic variables. The threshold for statistical significance was set at 5% (P<0.05). Results: The sample comprised panoramic radiographs from 2054 patients, predominantly female (59.2%), with a mean age of 27.2±11.5 years. Overall, 4066 impacted 3Ms were evaluated, revealing 471 (11.6%) developmental and 710 (17.5%) acquired pathoses. Among the developmental pathoses, 460 (95.2%) were indicative of dentigerous cysts. Male sex, lower 3M location, vertical or distoangular positioning, and incomplete root formation were associated with an elevated likelihood of developmental pathology. Lower tooth position, complete root formation, and partial eruption were linked to an increased probability of an acquired pathology in the third or second molar. Conclusion: The prevalence of pathologic conditions associated with impacted 3Ms was low. Male sex, lower 3M placement, horizontal or distoangular positioning, and incomplete root formation were associated with developmental pathoses, while lower tooth position, complete root formation, and partial eruption were related to acquired pathoses.