Journal of Mathematical and Fundamental Sciences
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The Use of Solar Radiation in Agricultural Processing
No full textAbstract. Recent solar radiation data in different parts of Malaysia indicates that Malaysia has an abundant energy resource that could be tapped and used for agricultural processing. A brief survey on the potential uses of this solar energy is given and mention is made of the types of application, the products and processes involved. Examples for Malaysian agricultural products are used. Ringkasan. Data terakhir mengenai radiasi matahari di beberapa tempat yang berbeda-beda di Malaysia memberikan indikasi bahwa Malaysia memiliki sumber enersi yang berlebihan yang dapat digunakan untuk pengolahan hasil-hasil pertanian. Suatu penelaahan mengenai potensi penggunakan enersi matahari diberikan secara singkat dan disebutkan pula beberapa jenis penggunaan, macam hasil olahan dan cara pengolahan yang terlibat. Beberapa hasil pertanian Malaysia digunakan sebagai contoh
Growth of Human Dermal Fibroblasts on Polyvinyl Alcohol-Silk Fibroin Nanofiber Scaffold
Get PDFSkin tissue engineering is a developing technology to heal severe wounds. Combining polyvinyl alcohol (PVA) and silk fibroin (SF) nanofibers is a promising method of developing a skin scaffold because the resulting structure mimics collagen fibers. The aim of this research was to study the growth of human dermal fibroblasts (HDF) on a polyvinyl alcohol-silk fibroin (PVA-SF) nanofiber scaffold that was produced by electrospinning. Morphological characterization and chemical analysis of the scaffold were performed by scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FTIR), and contact angle measurement. The biocompatibility of the scaffold was tested by MTT cytotoxicity assay, SEM analysis, adherence ratio calculation, and analysis of the HDF growth curve for 9 days. The FTIR results confirmed the presence of SF and PVA. The average fiber diameter and pore size of the PVA scaffold were greater than those of the PVA-SF scaffold. Both scaffolds had hydrophilic properties and were not cytotoxic. Thus, HDF can attach and grow on both types of scaffold better than HDF seeded on a polystyrene plate. In conclusion, the addition of SF to the PVA nanofibers caused bead formation, which affected the substrate topography, decreased hydrophilicity and also decreased the fiber diameter and pore size in the nanofiber scaffold compared to the PVA nanofiber scaffold without SF addition. SF addition increases cell attachment to the nanofiber scaffold and has potential to facilitate HDF cell growth
Shrodinger Equation in General Relativity
No full textAbstract. Dalam tulisan ini diturunkan persamaan Schrodinger ke dalam TRU dari suatu partikel bermuatan dalam potensial Coulomb, yang diperoleh sebagai approksimasi dari pada persamaan Klein-Gordon dalam TRU dengan anggapan bahwa energi kinetik dan potensialnya kecil sekali dibandingkan terhadap energi diam mc2. Potensial gravitasi-Newton muncul di dalam formulasi ini sebagaimana diharapkan dalam bentuk non-relativitistiknya. Ditunjukkan pula disini bahwa persamaan radialnya memiliki titik r "“ o sebagai titik singular yang non-essensial, yang mana memberikan eksistensi solusinya dalam penguraian deret sekitar r = o. Solusi approksimasi dengan mempergunakan teori Perturbasi ternyata memunculkan beberapa divergensi yang masih belum terpecahkan dalam tulisan ini. Ringkasan. Schrodinger equation in GR for a charged particle in Coulomb potential is presented, derived from the formulation of Klein-Gordon equation in GR with an assumption that the kinetic and potential energy are small in comparison with the rest energy mc2. The term Newtonian, potential appeared directly as expected from the non-relativistic Schrodinger equation in the Newtonian gravitational field. It is shown that its radial equation posseses a non-essential singular point at r = 0, therefore it has a power series solution about r = 0. Perturbation theory is used to find its approximation solution, encountered some divergences that remained unsolved.
Reproduksi pada Suatu Jenis Chiroptera dari Daerah Tropis Tadarida plicatus plicatus (Horsfield)
Get PDFRingkasan. Siklus reproduksi Tadarida plicatus plicatus (Horsfield) telah diselidiki selama dua tahun berturut-turut. Tenyata dalam setahun terdapat dua kali masa berkembang-biak, yakni pada bulan-bulan Maret-April serta September-Oktober. Type uterusnya bicornuatus dengan tanduk kiri yang tereduksi, karena itu implantasi embryo selalu berlangsung dalam tanduk uterus yang kanan. Abstract. The reproductive cycle of Tadarida plicatus plicatus (Horsfield) has been studied for two consecutive years. Results show a biannual breeding season, in March-April and September-October. The uterus is bicornuate with a reduced left horn, implantation of embryo therefore always occurs in the right horn.
Produk Langsung Lengkap dari Grup
Get PDFLet Γ = {Gi} be a countable collection of groups. Then its cartesian product can be made into a group in a very obvious way. This new group is called the external direct product of the groups Gi from the collection Γ. On the other hand we have the internal direct product of subgroups of a group. For a finite collection the internal direct product of subgroups is isomorphic with the external direct product. It is no longer true when the collection is infinite, even countable. For an infinite collection of groups the direct product must be defined in the other way. The main purpose of this paper is to give a general concept of the direct product of an arbitrary collection of groups, which is called THE COMPLETE DIRECT PRODUCT OF GROUPS.
Respective Influences of Indian Ocean Dipole and El Niño-Southern Oscillation on Indonesian Precipitation
Get PDFThe respective influences of the Indian Ocean Dipole (IOD) and El Niño-Southern Oscillation (ENSO) on Indonesian precipitation were evaluated using monthly precipitation data from the Global Precipitation Climatology Centre (GPCC) for January 1948 to December 2013. Simultaneous correlation between seasonal precipitation anomalies and climate indices for these two types of climate modes revealed that IOD events have a significant correlation with the precipitation over southern Sumatra, Java, southern Kalimantan, the Nusa Tenggara Islands, some parts of Sulawesi and eastern Papua. Meanwhile, ENSO events have a significant correlation with the precipitation over southern Sumatra, Java, Kalimantan, Sulawesi, and Papua. Droughts during the dry season (JJA and SON) typically occur when a positive IOD event simultaneously occurs with an El Niño event associated with anomalous low SST observed in the Indonesian seas and the southeastern equatorial Indian Ocean. Low SST anomalies lead to low-level wind divergence and reduce water vapor in the lower atmosphere, supress atmospheric convection over the Indonesian region and then cause a decrease in precipitation
Correlation of Hypoxia and Pro-senescence Protein Expression in Green Sea Turtle (Chelonia mydas) Lung Epithelial and Dermal Fibroblast Cell Culture
Get PDFRecent studies have shown hypoxia-induced gene expression correlated with cellular senescence. HIF-1α (hypoxia-inducible factor 1-alpha), p53, and pRB were induced under hypoxia and correlated with cellular senescence. The localization and expression of HIF-1α, p53, and pRB in Chelonia mydas lung epithelial and dermal fibroblast cell cultures were analyzed under normoxic and hypoxic conditions (at 4 and 24 hours). Human dermal fibroblast was used for comparison purposes. Protein localization was analyzed with immunocytochemistry, while protein expression was analyzed with the Western blot and enhanced chemiluminescence (ECL) method. HIF-1α, p53, and pRB were localized in the nuclei of the C. mydas cell cultures treated with hypoxia. The C. mydas lung epithelial cell cultures had a higher increase of HIF-1α expression than the human dermal fibroblast cell culture. The hypoxic conditions did not affect p53 expression significantly in C. mydas lung epithelial and dermal fibroblast cell cultures. Meanwhile, pRB expression changed significantly under hypoxia in the C. mydas dermal fibroblast cells. Expression of p53 and pRB in the human cell cultures was higher than in the C. mydas cell cultures. This research suggests that C. mydas and human cell cultures have different pro-senescence protein expression responses under hypoxic conditions
Enhancing the Stability of Lanczos-type Algorithms by Embedding Interpolation and Extrapolation for the Solution of Systems of Linear Equations
No full textA new method to treat the inherent instability of Lanczos-type algorithms is introduced. It enables us to capture the properties of the sequence of iterates generated by a Lanczos-type algorithm by interpolating on this sequence of points. The interpolation model found is then used to generate a point that is outside the range. It is expected that this new point will link up the rest of the sequence of points generated by the Lanczos-type algorithm if breakdown does not occur. However, because we assume that the interpolation model captures the properties of the Lanczos sequence, the new point belongs to that sequence since it is generated by the model. This paper introduces the so-called Embedded Interpolation and Extrapolation Model in Lanczos-type Algorithms (EIEMLA). The model was implemented in algorithms A13/B6 and A13/B13, which are new variants of the Lanczos algorithm. Individually, these algorithms perform badly on high dimensional systems of linear equations (SLEs). However, with the embedded interpolation and extrapolation models, EIEM A13/B6 and EIEM A13/B13, a substantial improvement in the performance on SLEs with up to 105 variables can be achieved
Flavonoid Compounds from the Herb of Krokot (Lygodium microphyllum) and their antioxidant activity against DPPH
No full textSix flavonoid compounds, kaempferol (1), quercetin (2), acacetin (3), quercetin-3-O-β-D-glucopyranoside (4), kaempferol-3-O-β-D-glucopyranoside (5), and isorhamnetin-3-O-β-D-glucopyranoside (6), were isolated from the methanol extract of the Lygodium microphyllum herb. The chemical structures of compounds 1-6 were identified on the basis of spectroscopic evidence and comparison with previously reported spectral data. Compounds 1-6 were isolated for first time from this plant. Their antioxidant activity against DPPH (2,2-Diphenyl-1-picrylhydrazyl) was evaluated. Among the compounds, quercetin (2) showed high antioxidant activity with IC50 values of 6.94 ± 0.03 μg/mL
