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    19488 research outputs found

    SMAS: A solution-based multi-agent system for improving problem solving skills in computer programming

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    In this research, a solution-based multi-agent system (SMAS) is proposed, which benefits from a novel automatic text-to-flowchart conversion approach in order to improve students' problem solving skills. The aim is to introduce the early stages of learning programming (CS1). By using SMAS, students can focus on solution designing activities in the form of flowchart development more than on language and syntax. Ultimately, an experimental study is devised to assess the success of SMAS as a tool to aid students with problem solving activities and learning computer programming. In total, 30.4% of problems that were left unresolved in previous sessions were solved by students in the control group, whereas 69.7% of previously unresolved problems were solved by students in the experimental group who used SMAS. Therefore, the use of SMAS in practice is supported, as the results indicate considerable gains for the experimental group over the control group

    Microwave-assisted conversion of agro-industrial copra residue oil to diesel engine compatible fatty acid methyl esters

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    Due to the increasing concern towards fossil fuel reserve and its fluctuating price, many countries shifted towards producing biodiesel as an alternative green fuel. In this study, the main objective is to synthesis biodiesel from coconut copra, an agro-industrial residue, as potential feedstock using different transesterification techniques, namely stirring mechanical-assisted technique (SAT), ultrasonic-assisted technique (UAT), and microwave-assisted technique (MAT). The current study will show comparison between the biodiesel yields, fatty acid methyl ester (FAME) compositions and fuel properties of the transesterification techniques used. The result showed that the copra residue biodiesel (CRB) using SAT produced the highest yield of biodiesel compared to UAT and MAT, which are 96.85% (±0.69), 93.79% (±1.00), and 91.76% (±0.87), respectively. Furthermore, different volumes of solvent and catalyst amount were found to affect the biodiesel yields, relatively. On the other hand, for FAME compositions, insignificant results were observed. The fuel properties in CRB complied with the international standards, thus, showing high compatibility to be used in diesel engine

    Hydrolysis of microcrystalline cellulose isolated from waste seeds of Leucaena leucocephala for glucose production

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    The waste seeds of Leucaena leucocephala (LLS) used in this study were unused residues obtained after oil and polysaccharides extraction. The microcrystalline cellulose (MCC) was isolated from LLS by acid treatment. MCC produced was, then, further converted to glucose by using sulphuric acid at 121 °C by varying the acid concentration and reaction time. The sugar composition was analyzed by using the phenol-sulfuric acid method and pre-column derivatization HPLC technique. The yield of glucose ranging from 70–85% could be obtained from MCC hydrolyzates, depending on the hydrolysis factors, which corresponding to around 57-75% of the percentage conversion of MCC to glucose.Cellulose isolated from LLS was, therefore, potentially suitable to be utilized in liquid biofuels and other value-added chemicals such as bioethanol, 5-hydroxymethylfurfural(HMF), and levulinic acid

    Comprehensive functional profiling of long non-coding RNAs through a novel pan-cancer integration approach and modular analysis of their protein-coding gene association networks

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    Background: Long non-coding RNAs (lncRNAs) are emerging as crucial regulators of cellular processes in diseases such as cancer, although the functions of most remain poorly understood. To address this, here we apply a novel strategy to integrate gene expression profiles across 32 cancer types, and cluster human lncRNAs based on their pan-cancer protein-coding gene associations. By doing so, we derive 16 lncRNA modules whose unique properties allow simultaneous inference of function, disease specificity and regulation for over 800 lncRNAs. Results: Remarkably, modules could be grouped into just four functional themes: transcription regulation, immunological, extracellular, and neurological, with module generation frequently driven by lncRNA tissue specificity. Notably, three modules associated with the extracellular matrix represented potential networks of lncRNAs regulating key events in tumour progression. These included a tumour-specific signature of 33 lncRNAs that may play a role in inducing epithelial-mesenchymal transition through modulation of TGFβ signalling, and two stromal-specific modules comprising 26 lncRNAs linked to a tumour suppressive microenvironment and 12 lncRNAs related to cancer-associated fibroblasts. One member of the 12-lncRNA signature was experimentally supported by siRNA knockdown, which resulted in attenuated differentiation of quiescent fibroblasts to a cancer-associated phenotype. Conclusions: Overall, the study provides a unique pan-cancer perspective on the lncRNA functional landscape, acting as a global source of novel hypotheses on lncRNA contribution to tumour progression. © 2019 The Author(s)

    Automated craniofacial landmarks detection on 3D image using geometry characteristics information

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    Background: Indirect anthropometry (IA) is one of the craniofacial anthropometry methods to perform the measurements on the digital facial images. In order to get the linear measurements, a few definable points on the structures of individual facial images have to be plotted as landmark points. Currently, most anthropometric studies use landmark points that are manually plotted on a 3D facial image by the examiner. This method is time-consuming and leads to human biases, which will vary from intra-examiners to inter-examiners when involving large data sets. Biased judgment also leads to a wider gap in measurement error. Thus, this work aims to automate the process of landmarks detection to help in enhancing the accuracy of measurement. In this work, automated craniofacial landmarks (ACL) on a 3D facial image system was developed using geometry characteristics information to identify the nasion (n), pronasale (prn), subnasale (sn), alare (al), labiale superius (ls), stomion (sto), labiale inferius (li), and chelion (ch). These landmarks were detected on the 3D facial image in .obj file format. The IA was also performed by manually plotting the craniofacial landmarks using Mirror software. In both methods, once all landmarks were detected, the eight linear measurements were then extracted. Paired t-test was performed to check the validity of ACL (i) between the subjects and (ii) between the two methods, by comparing the linear measurements extracted from both ACL and AI. The tests were performed on 60 subjects (30 males and 30 females). Results: The results on the validity of the ACL against IA between the subjects show accurate detection of n, sn, prn, sto, ls and li landmarks. The paired t-test showed that the seven linear measurements were statistically significant when p < 0.05. As for the results on the validity of the ACL against IA between the methods, ACL is more accurate when p ≈ 0.03. Conclusions: In conclusion, ACL has been validated with the eight landmarks and is suitable for automated facial recognition. ACL has proved its validity and demonstrated the practicability to be used as an alternative for IA, as it is time-saving and free from human biases

    Squamous Cell Carcinoma Biomarker Sensing on a Strontium Oxide-Modified Interdigitated Electrode Surface for the Diagnosis of Cervical Cancer

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    Cervical cancer is a life-threatening complication, appearing as the uncontrolled growth of abnormal cells in the lining of the cervix. Every year, increasing numbers of cervical cancer cases are reported worldwide. Different identification strategies were proposed to detect cervical cancer at the earlier stages using various biomarkers. Squamous cell carcinoma antigen (SCC-Ag) is one of the potential biomarkers for this diagnosis. Nanomaterial-based detection systems were shown to be efficient with different clinical biomarkers. In this study, we have demonstrated strontium oxide-modified interdigitated electrode (IDE) fabrication by the sol-gel method and characterized by scanning electron microscopy and high-power microscopy. Analysis of the bare devices indicated the reproducibility with the fabrication, and further pH scouting on the device revealed that the reliability of the working pH ranges from 3 to 9. The sensing surface was tested to detect SCC-Ag against its specific antibody; the detection limit was found to be 10 pM, and the sensitivity was in the range between 1 and 10 pM as calculated by 3σ. The specificity experiment was carried out using major proteins from human serum, such as albumin and globulin. SCC-Ag was shown to be selectively detected on the strontium oxide-modified IDE surface. © 2019 Hongqing Wang et al

    Mini-implant supported canine retraction with micro-osteoperforation: A split-mouth randomized clinical trial

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    Objectives: To investigate, using a split-mouth randomized clinical design, the effect of micro-osteoperforation (MOP) on mini-implant supported canine retraction using fixed appliances. Materials and Methods: Thirty subjects (seven males and 23 females) with a mean age of 22.2 (3.72) years were randomized into three canine retraction groups: Group 1 (MOP 4-weekly maxilla/ 8-weekly mandible; n = 10); Group 2 (MOP 8-weekly maxilla/12-weekly mandible; n = 10) and Group 3 (MOP 12-weekly maxilla/4-weekly mandible; n = 10) measured at 4-week intervals over 16 weeks. Subjects also completed pain (5-point Likert scale) and pain impact (Visual Analogue Scale) questionnaires. The primary outcome was the amount of canine retraction over 16 weeks at MOP (experimental) and non-MOP (control) sites. Results: Mean overall canine retraction was 4.16 (1.62) mm with MOP and 3.06 (1.64) mm without. After adjusting for differences between jaws, all MOP groups exhibited significantly higher canine distalization than the control group: 0.89 mm more (95% confidence interval [CI] = 0.19 to 1.59 mm; P =.01) in the MOP-4 group, 1.08 mm more (95% CI = 0.49 to 1.68 mm; P =.001) in the MOP-8 group and 1.33 mm more (95% CI = 0.55 to 2.10 mm; P =.002) in the MOP-12 group. All subjects reported pain associated with MOP with 60% classifying it as moderate and 15% severe. The main impact of this reported pain was related to chewing and speech. Conclusions: MOP can increase overall mini-implant supported canine retraction over a 16-week period of observation but this difference is unlikely to be clinically significant. © 2019 by The EH Angle Education and Research Foundation, Inc

    Optimization of see do il extraction process parameters from Brucea javanica using Design of Experiment (DoE)

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    The project was done to improve Soxhlet process for extraction of oil for seeds of Brucea javanica and explore its various applications. The optimization was done by RSM (response surface methodology) using Box Behnken design of experiment (DoE). Properties of the Brucea javanica oil (BJO) was determined using Gas/Mass Spectrometric approach and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. GCMS analysis indicated that important fatty acid are presence in BJO and FTIR suggested the presence of core functional groups in BJO. Quadratic model was used to analyse the results obtained from the optimised experimental design. ANOVA of developed model showed good presentation of model with R 2 value of 0.9078. Similarly, it was discovered that model were significant because their probability values (p-values) were discovered to be less than 0.05. The design of experiment showed a highest yield of 44.89 % at 75°C, 6hour extraction time and hexane 425ml

    An in vitro Three-Dimensional Co-Culture System for Ameloblastoma Modelling (Sistem Ko-Kultur Tiga Dimensi secara in vitro untuk Pemodelan Ameloblastoma)

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    Ameloblastoma, the most clinically significant odontogenic epithelial tumor, is a locally-invasive and destructive lesion in the jawbones. However, the nature of this infiltrativeness and destructive behavior remains ill-understood. To address this, we established an in vitro three-dimensional (3D) co-culture system to simulate an amelobastoma disease model aimed at investigating the interactions between tumor cells and osteoblasts. Osteoblastic cell lines (KUSA/A1 and mc3T3-E1) and one stromal cell line (ST2) were separately co-seeded with ameloblastoma-derived cell line (AM-1) in a collagen scaffold (representing the extracellular bone matrix) and incubated with mineralization medium. Inununohistochemistry, double immunofluorescence and mineralization assay were performed. Only Am-1/KUsA-A1 co-culture showed a significant increase in Am-1 cell count, suggesting that heterotypic cell-cell interaction promotes tumoral cell growth, while formation of visible Am-1 epithelial nest-like structures resembling ameloblastoma cells in their native state, suggest morphodffferentiation. A RANK-high, RANKL-low and osteoprotegerin-low immunoprofile in co-culture AM-1 cells implies deregulated osteoclastogenesis. Mineralization assays showed diminished calcification in Am-1/KUSA-A1 co-culture extracellular matrix suggesting an altered local bone metabolism. In contrast, KUSA/A1 monocultures showed abundant extracellular matrix calcification. Taken together, these results suggest that a 3D co-culture system as an amelobastoma disease model provides insights that bidirectional ameloblastoma-osteoblastic interactions might play a role in modulating tumor growth and osteoclastogenesis

    The Sella Turcica Dimensions in 12-Year-Old Southern Chinese: A Cross-Sectional Study (Dimensi Sella Turcica pada Populasi Berusia 12 tahun di Selatan China: Suatu Kajian Keratan Rentas)

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    The objective of the study was to measure the dimensions of the sella turcica in southern Chinese population. This retrospective study measured dimensions of sella turcica from lateral cephalometric radiographs obtained from the University of Hong Kong research database with a total of 582 (277 females and 305 males) 12-year-old southern Chinese children, who were randomly selected from schools in Hong Kong. Measurements were made using Image) (V1 .45s) software for Windows with Frankfurt plane as the horizontal reference direction. Dimensions between genders were compared using Student's t-tests. The current study found the antero-posterior length and width were 9.13 mm (SD 2.05) and 9.76 mm (SD 1.54), respectively. The sella was highest posteriorly (7.97 mm; SD 1.75 mm) and shortest anteriorly (7.56 mm; SD 1.42). Sella height anterior, sella height median and sella area were greater (p<0.05) in females by 0.53 mm, 0.24 mm and 3.48 mm(2), respectively. In conclusion, this study provides the reference parameters for the dimensions of sella turcica for the Southern Chinese population


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