The purpose of the study is to investigate the utilisation of Napier fiber (Pennisetum purpureum) as a source for the fabrication of cellulose nanofibers (CNF). In this study, cellulose nanofibers (CNF) from Napier fiber were isolated via ball-milling assisted by acid hydrolysis. Acid hydrolysis with different molarities (1.0, 3.8 and 5.6 M) was performed efficiently facilitate cellulose fiber size reduction. The resulting CNFs were characterised through Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), particle size analyser (PSA), field-emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The FTIR results demonstrated that there were no obvious changes observed between the spectra of the CNFs with different molarities of acid hydrolysis. With 5.6 M acid hydrolysis, the XRD analysis displayed the highest degree of CNF crystallinity at 70.67%. In a thermal analysis by TGA and DTG, cellulose nanofiber with 5.6 M acid hydrolysis tended to produce cellulose nanofibers with higher thermal stability. As evidenced by the structural morphologies, a fibrous network nanostructure was obtained under TEM and AFM analysis, while a compact structure was observed under FESEM analysis. In conclusion, the isolated CNFs from Napier-derived cellulose are expected to yield potential to be used as a suitable source for nanocomposite production in various applications, including pharmaceutical, food packaging and biomedical fields.

This paper aims to identify and study the blood flow and acoustics characteristics of different degrees of stenosis in the carotid artery. Blood flow will produce acoustics, but the presence of different levels of stenosis are expected to produce different acoustic characteristics. The blood flow and acoustic characteristics are simulated by using computational fluid dynamics software (CFD). Several three-dimensional models of carotid arteries that have different degrees of stenosis are used together with a normal/healthy carotid artery - i.e., 30% and 70% degrees of blockage. The geometry of 30% and 70% stenosed model are computationally generated from a normal carotid artery geometry. In addition, the blood viscosity level was also increased in this study to a value of 0.005 kgms-1 (from the normal viscosity of 0.004 kgms-1) to compare the effect of hyperglycaemia (i.e., diabetes mellitus) that may bring additional complications to blood flow. Pulsatile simulations are used for all cases in order to mimic the exact blood flow condition in which the inlet velocity and outlet pressure change with time. The present study shows that as the degree of stenosis increases at the common carotid artery (CCA), the velocity at the internal carotid artery (ICA) and external carotid artery (ECA) outlet increases. The maximum velocity changes for ICA at the systolic peak from normal to 70% degree of stenosis for carotid artery shows an increase by 8%, while an opposite trend is observed for the maximum velocity changes of ECA at the systolic peak, where a reduction by 3% occurs from normal to 70% degree of stenosis for carotid artery. In terms of viscosity, as the viscosity of the blood increases, the velocity of the blood flow decreases in all geometry carotid arteries and may potentially provide further complications on clinical problems. The acoustic simulation showed that the acoustic power increases by 5% and 20% for carotid artery geometry that has 30% and 70% degree of stenosis, respectively. The present study indicates potential for further developing non-invasive acoustic means to diagnose and measure stenosis in carotid arteries.

Realiti Teraruh (AR) adalah teknologi yang memperoleh penggabungan secara terus terhadap kandungan digital yang dibuat oleh komputer dengan dunia nyata. Walaubagaimanapun, bahan kandungan berbentuk ilmiah dalam fitur AR terutama kandungan buatan tempatan amat jarang ditemui di dalam platform media sosial, maka terdapat keperluan untuk menambah bahan ilmiah buatan tempatan. Oleh itu,objektif kajian ini adalah untuk melihat persepsi dan sikap pelajar terhadap bahan kandungan aktiviti pembelajaran dalam bentuk AR menggunakan platform Instagram. Seramai 38 orang pelajar yang mengambil kursus Analisis Komponen Mekanikal terlibat dengan borang soal selidik diedarkan kepada mereka selepas mereka selesai menjalankan tugasan melibat kandungan tersebut. Hasil dapatan menunjukkan 90% pelajar berasa sangat setuju/setuju bahawa mereka seronok dengan bahan pembelajaran sebegini. Semua pelajar memberikan skala 3 dan ke atas bagi kenyataan aktiviti ini membantu meningkatkan kemahiran komunikasi mereka. 75% pelajar juga sangat setuju/setuju agar kandungan berbentuk AR ini ditambah dalam kursus mereka bagi membantu pemahaman kursus dan meningkatkan pengalaman pembelajaran mereka. Maka, kandungan aktiviti pembelajaran fitur kuiz AR ini dilihat dapat membantu meningkatkan pengalaman pembelajaran mereka serta membina keyakinan mereka untuk berkomunikasi