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Objective: To evaluate the accuracy of MeMoSA®, a mobile phone application to review images of oral lesions in identifying oral cancers and oral potentially malignant disorders requiring referral. Subjects and Methods: A prospective study of 355 participants, including 280 with oral lesions/variants was conducted. Adults aged ≥18 treated at tertiary referral centres were included. Images of the oral cavity were taken using MeMoSA®. The identification of the presence of lesion/variant and referral decision made using MeMoSA® were compared to clinical oral examination, using kappa statistics for intra‐rater agreement. Sensitivity, specificity, concordance and F1 score were computed. Images were reviewed by an off‐site specialist and inter‐rater agreement was evaluated. Images from sequential clinical visits were compared to evaluate observable changes in the lesions. Results: Kappa values comparing MeMoSA® with clinical oral examination in detecting a lesion and referral decision was 0.604 and 0.892, respectively. Sensitivity and specificity for referral decision were 94.0% and 95.5%. Concordance and F1 score were 94.9% and 93.3%, respectively. Inter‐rater agreement for a referral decision was 0.825. Progression or regression of lesions were systematically documented using MeMoSA®. Conclusion: Referral decisions made through MeMoSA® is highly comparable to clinical examination demonstrating it is a reliable telemedicine tool to facilitate the identification of high‐risk lesions for early management. [ABSTRACT FROM AUTHOR]

Introduction: Dental education involves performing clinical procedures on patients under expert supervision. The COVID‐19 pandemic has disrupted routine face‐to‐face teaching‐learning‐assessment dynamics world over. This study assessed the self‐perceived preparedness of dental undergraduate students for practice, whose clinical training was interrupted by the COVID‐19 pandemic from dental schools across Malaysia. Materials and Methods: This cross‐sectional web‐based questionnaire survey was done among new dental graduates of the academic year 2019‐2020 and the final year undergraduate students (academic year 2020‐2021) from dental schools in Malaysia, using the Dental Undergraduates Preparedness Assessment Scale (DU‐PAS), from 6th to 26th April 2021. The questionnaire addressed clinical skill competence, and cognitive and behavioral attributes. The number of respondents needed to achieve a confidence level of 95% with margin of error of 5% was 306. Results: A total of 453 (243 final year students and 210 new graduates) responded from dental schools nationwide, with a response rate of 30.6%. The overall mean score for preparedness for dental practice was 76.3±14.7, for clinical skills 39.7±7.3, and behavioral and cognitive attributes 36.5±9.1. New graduates had significantly higher mean preparedness score (78.6±14.4) as compared to students in their final year (74.2±14.7). Performing endodontic treatment on multi‐rooted teeth had the lowest perceived competency (29.8%), followed by assessing treatment needs of patients requiring orthodontics (37.1%), prescribing drugs (46.6%) and providing crowns using principles of tooth preservation (48.1%). Conclusions: Satisfactory scores were obtained for most attributes. The final‐year cohort was significantly less prepared for dental practice compared to the newly graduated cohort. [ABSTRACT FROM AUTHOR]

Tungsten and niobium incorporated KIT‐6 (WNb‐KIT‐6) materials were synthesized by a one‐pot sol‐gel method. During 2‐butene+ethylene metathesis with these materials at 450 °C, the propene yield is maximized (∼70 %) at a certain metal composition (∼20 wt% W and ∼1 wt% Nb), significantly surpassing those reported with an industrial WO3/SiO2 catalyst. The enhanced propene yield is attributed to better dispersion of W species on the catalyst surface and the formation of new active site precursors (O=)2W(O−Si)(O−Nb), as confirmed by XRD, TEM, H2‐TPR, XPS, EXAFS, and ToF‐SIMS techniques. Complementary DFT calculations reveal a positive correlation between the O=W=O bond angle and the propene yield. We therefore speculate that the −O−Nb moiety tunes the electronic environment around the W atom and increases the propene yield. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the efficacy of mouth self-examination (MSE) as a self-screening tool for detection of oral mucosal lesions among an Indigenous population in Malaysia at high risk for oral premalignant and malignant disorders.Methods: Two villages were selected as the sampling frame based on prevalence of tobacco and betel quid chewing habit. Respondents were asked to check their mouth for presence of lesion or abnormalities. Education on oral cancer, including MSE, was provided. Subsequently, respondents were asked to perform MSE. Finally, a clinical oral examination (COE) was done by a specialist and the presence of oral mucosal lesions was recorded.Results: Almost 64.5 percent of respondents exhibited high levels of difficulty and low mucosal visualization and retracting ability, whereas 3.0 percent demonstrated high attention level when performing MSE. Prevalence of oral mucosal lesions was 59.0 percent, whereas the prevalence of oral potentially malignant disorders (OPMDs) was 9.0 percent. Detection of oral lesions by respondents using MSE was lower than detection by the gold standard. Sensitivity and specificity of MSE for detection of all types of lesions were 8.6 and 95.0 percent respectively. When analyzing each lesion type separately, MSE was found to be most sensitive in detection of swellings (10.0 percent), and most specific in identifying white lesions (97.8 percent). For detection of OPMDs, although specificity was high (98.9 percent), sensitivity (0 percent), and +LR (0) was poor.Conclusion: MSE is not an effective self-screening tool for early detection of potentially malignant lesions for this population. [ABSTRACT FROM AUTHOR]

The relative amounts of acidic and basic sites in niobium-containing ordered mesoporous silicates (Nb-KIT-6) are tunable with metal loading. The acidity and basicity change from 0.11 to 0.34 mmol NH3-equiv./g cat. and 0.17 to 0.31 mmol CO2-equiv./g cat., respectively, as the Nb loading is increased from 1.5 to 10.9%. This work harnesses this unique feature to better understand acidity and basicity effects on ethanol conversion activity and product selectivity. It is shown that the yields of ethylene and acetaldehyde, the dominant products, are tuned with Nb loading. Catalyst characterization results and designed kinetic experiments provide evidence of acid-base pairs involved in the formation of various products. A macrosite kinetic model based on these observations and published mechanistic pathways fits the data for formation of the major products (ethylene, acetaldehyde, diethyl ether, and ethane) remarkably well. These results provide guidance for the rational design of bifunctional mesoporous materials exhibiting tunable acidity and basicity. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2888-2899, 2017 [ABSTRACT FROM AUTHOR]

Purpose The purpose of this preliminary study was to evaluate the flexural properties of poly(methyl methacrylate) (PMMA) reinforced with oil palm empty fruit bunch (OPEFB) fiber. Materials and Methods The flexural strength and flexural modulus of three OPEFB fiber-reinforced PMMA were compared with a conventional and a commercially available reinforced PMMA. The three test groups included OPEFB fibers of 0.5 mm thickness, 2.0 mm thickness, and OPEFB cellulose. Results All test group specimens demonstrated improved flexural strength and flexural modulus over conventional PMMA. Reinforcement with OPEFB cellulose showed the highest mean flexural strength and flexural modulus, which were statistically significant when compared to the conventional and commercially reinforced PMMA used in this study. OPEFB fiber in the form of cellulose and 0.5 mm thickness fiber significantly improved flexural strength and flexural modulus of conventional PMMA resin. Further investigation on the properties of PMMA reinforced with OPEFB cellulose is warranted. Conclusions Natural OPEFB fibers, especially OPEFB in cellulose form, can be considered a viable alternative to existing commercially available synthetic fiber reinforced PMMA resin. [ABSTRACT FROM AUTHOR]

ABSTACT Interconnected, amorphous three dimensional, iron-containing TUD-1 (FeTUD-1, Si/Fe = 25) mesoporous silica was subjected as a catalyst for degradation of refractory organic compound. The catalyst was prepared by economical, eco-friendly sol-gel method and characterized by various techniques, such as X-ray diffraction, N2 sorption studies, diffuse reflectance UV-Vis, Fourier transform IR, inductively coupled plasma optical emission spectrometry, scanning electron microscopy and electron paramagnetic resonance to understand the morphology and nature of the Fe species. The catalytic activity was evaluated by the oxidation of N, N-diethyl- p-phenylenediamine (DPD) with H2O2 and air. All degradation studies were analyzed by UV-Vis spectroscopy, chemical oxygen demand, and total organic carbon measurements. The effect of time, pH, H2O2 concentration, and amount of FeTUD-1 catalyst on the DPD degradation were also examined. Heterogeneous FeTUD-1 showed a good catalytic performance than homogeneous FeSO4 Fenton oxidation process. Besides, leaching of Fe (∼12%) was observed at pH 2. The reaction kinetics of FeTUD-1 catalyzed degradation illustrates a first-order kinetics. Possible degradation mechanism and formed products are discussed. [ABSTRACT FROM AUTHOR]

Excessive proteolytic degradation of fibronectin (FN) has been implicated in impaired tissue repair in chronic wounds. We previously reported two strategies for stabilizing FN against proteolytic degradation; the first conjugated polyethylene glycol (PEG) through cysteine residues and the second conjugated PEG chains of varying molecular weight on lysine residues. PEGylation of FN via lysine residues resulted in increased resistance to proteolysis with increasing PEG size, but an overall decrease in biological activity, as characterized by cell and gelatin binding. Our latest method to stabilize FN against proteolysis masks functional regions in the protein during lysine PEGylation. FN is PEGylated while it is bound to gelatin Sepharose beads with 2, 5, and 10 kDa PEG precursors. This results in partially PEGylated FN that is more stable than native FN and whose proteolytic stability increases with PEG molecular weight. Unlike completely PEGylated FN, partially PEGylated FN has cell adhesion, gelatin binding, and matrix assembly responses that are comparable to native FN. This is new evidence of how PEGylation variables can be used to stabilize FN while retaining its activity. The conjugates developed herein can be used to dissect molecular mechanisms mediated by FN stability and functionality, and address the problem of FN degradation in chronic wounds. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:277-288, 2015 [ABSTRACT FROM AUTHOR]

Delayed wound healing in many chronic wounds has been linked to the degradation of fibronectin ( FN) by abnormally high protease levels. We sought to develop a proteolytically stable and functionally active form of FN. For this purpose, we conjugated 3.35 kDa polyethylene glycol diacrylate ( PEGDA) to human plasma fibronectin ( HPFN). Conjugation of PEGDA to HPFN or HPFN PEGylation was characterized by an increase of approximately 16 kDa in the average molecular weight of PEGylated HPFN compared to native HPFN in SDS-PAGE gels. PEGylated HPFN was more resistant to α chymotrypsin or neutrophil elastase digestion than native HPFN: after 30 min incubation with α chymotrypsin, 56 and 90% of native and PEGylated HPFN respectively remained intact. PEGylated HPFN and native HPFN supported NIH 3T3 mouse fibroblast adhesion and spreading, migration and focal adhesion formation in a similar manner. Fluorescence microscopy showed that both native and PEGylated HPFN in the culture media were assembled into extracellular matrix ( ECM) fibrils. Interestingly, when coated on surfaces, native but not PEGylated HPFN was assembled into the ECM of fibroblasts. The proteolytically stable PEGylated HPFN developed herein could be used to replenish FN levels in the chronic wound bed and promote tissue repair. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 493-504, 2013 [ABSTRACT FROM AUTHOR]