Journal of Mathematical and Fundamental Sciences
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New H-ALPHA Emission Stars in A Region to the East of the T-Association Near Rho Ophiuci
Get PDFThe result of a survey of H-alpha emission objects in an area of approximately 25 square degrees centered on the star CD -24°12765 (R.A.=16h38.m5; Dec.=-24°22';1950), is presented. Only 33% of H-alpha emission stars discovered by Dolidze and Arakelyan (1959) which are located in the present survey region, are redetected in our plates. A total number of 32 new H-alpha emission objects are found. Their position and finding charts are given
Tjatatan Mengenai Stratigraphy Pegunungan Karangbolong, Djawa Tengah
Get PDFThe Karangbolong Mountains belong to the zone of Southern Mountains in Java. The former consists of three series rocks, the oldest being the "Old Andesite" Formation composed of andesitic eruptive and intrusive of oligicene to aquitanian age, uncomprotably overlain by the Karangbolong Limestone Member of Tertiary f1-3. Toward the north the upper most limestone beds interlinger with beds of the Marl-tuff Member of Tertiary f3. After this time marine sedimentation in this area came to a halt. Both the Karangbolong Limestone and the Marl-tuff members together form the Karangbolong Marine Formation
Environmental Radioactivity in Bandung Area
Get PDFPenulis bersama-sama anggota Group Health Physics jang sedang mendapat pendidikan di bawah pimpinan Health Physicist dari IAEA, R.E. Alexander, telah melakukan pekerdjaan survey di sekitar kota Bandung. Survey ini adalah sebagai pendahuluan dari program survey yang kelak dilakukan setjara teratur, berhubung akan didirikannja projek reaktor inti di ITB. Maksud dari survey pendahuluan ini ialah untuk mendapatkan data dari tingkat radioaktiva dalam air, tanah, tumbuh-tumbuhan dan udara sebelum reaktor berdjalan, sehingga memungkinkan untuk mendapatkan perbandingan jang djelas djika kelak reaktor sudah berdjalan. Dengan alat-alat djang sangat terbatas jang terdapat di bagian Fisika dan di ITB pada dewasa ini, telah ditjoba untuk mendapatkan hasil jang sebaik-baiknja.
Unexpected Dimer from Demethylization Reaction of Eugenol under Acidic Conditions
Get PDFEugenol is an alkenyl phenol compound obtained as an essential oil from different parts of the clove such as its leaves and flowers. The essential oil from cloves can contain up to 90% eugenol, which is mainly responsible for its aroma. Eugenol is an interesting compound due to its simplicity and richness in functionalities, making it a valuable building block in synthesis. One of the key steps in eugenol transformation is demethylation to produce a hydroxycavicol. Demethylation is commonly carried out using a nucleophilic or an acidic method. In this study, a simple yet reliable nucleophilic method for demethylation using lithium chloride (LiCl) was attempted. The product was characterized by NMR, FTIR and HRMS spectroscopy. The absence of a methoxy signal at 3.5-4 ppm in the 1H NMR spectrum suggests that demethylation was successful. The HRMS result showed m/z 149.0596, confirming the formation of product. The demethylation reaction under acidic conditions formed a dimer of eugenol with the methoxy group still intact. This was supported by the 1H NMR data, which showed methoxy signals at 3.85 and 3.82 ppm and integration in the aromatic region, which suggests a dimer structure.
Induction of Matrix Metalloproteinases in Chondrocytes by Interleukin IL-1β as an Osteoarthritis Model
Get PDFOsteoarthritis (OA) is a chronic disease of the joints and bones due to trauma or other joint-related diseases (secondary). Synovial inflammation commonly causes disturbance in joint homeostasis, which is associated with OA. Enzymes such as aggrecanase and metalloproteinase generate cartilage damage, mediated by tumor necrosis factor (TNF-α) and interleukin (IL)-1. Pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6, are responsible for regulation of the extracellular matrix, cartilage degradation, and apoptosis of chondrocytes. This study aimed to observe the cell viability and expression level of matrix metalloproteinases (MMP-1 and MMP-3) and tissue inhibitor metalloproteinases (TIMP-1 and TIMP-2) in human chondrocyte cells (CHON-002) induced by IL-1β. CHON-002 was induced with IL-1β (0.1, 1 and 10 ng/mL) as an OA model. The viability of the cells was measured with a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxyme-thoxyphenyl)-2-(4-sulfophenyl)-2H-tetra zolium (MTS) assay, while expression of MMP-1, MMP-3, TIMP-1, and TIMP-2, was evaluated by RT-PCR. The viability of IL-1β-induced CHON-002 (CHON-002- IL-1β) cells at day 1 and 5 showed that treatment with up to 10 ng/mL of IL-1β was not toxic. Expression of TIMP-1 and TIMP-2 in CHON-002-IL-1β was lower compared to control, while that of MMP-1 and MMP-3 was higher compared to control. These results indicate that CHON-002 treated with 10 ng/mL IL-1β has expression patterns consistent with chondrocyte damage, so the CHON-002-IL-1β system may serve as a model for MMP induction in OA
Novel Tuning Scheme for Integrated Continuous Time Filter
No full textIn integrated continuous times (C.T.) filters, automatic tuning is very important, because the filter coefficients are very sensitive to device parameters. In this paper, novel tuning scheme for the integrated C.T. hand pass biquad filter is presented. This tuning scheme is used to tune the center of frequency (f0) of a band pass biquad filter which is 550 KHz. The bandwith of this filter is 535 KHz and the quality factor Q is equal to one. This filter consists of four CMOS operational transconductance amplifier (OTA) and two capacitors. The tuning scheme is realized with CMOS OTAs, a CMOS four quadrant analog multiplier with voltage output, a low pass filter and a DC amplifier. By varying the capacitor values of the band pass biquad filter 40% in both direction from the nominal value and varying the temperature from -100°C to 50°C, the center frequency of the filter remain constant at 550 KHz. It is simulated using SPICE software and operates with power supply voltages of ±5 V. Simulated results are presented and discussed
Effect of Annealing Treatment on the Optical Properties of Zinc Oxide (ZnO) thin film prepared by MOCVD
Get PDFThe annealing treatment of ZnO thin film at various temperatures was performed. The effect of this treatment on the optical properties of ZnO thin film were investigated in order to apply this film to optoelectronic devices. The optical transmittance spectra were measured and it was found that the transmittance in UV-VIS region decreased with annealing temperature . The loss of light is mainly due to the increase of carrier density, resulting from increased oxygen vacancies during the annealing process at 300°C. It was also found that the absorption edge shifted to lower energy when the film was annealed at 300°C in air
MOCVD Growth of GaSb and Al GaSb
Get PDFAbstract. GaSb and Al GaSb are narrow gap semiconductors, is of current interest, for its optoelectronic application in the near and medium infra-red region. The large ratio of the ionization coefficient of hole and electrons is key factor for high speed and low noise in APD. In this paper we report the frowth of GaSb and AlGaSb in a home made vertical MOCVD reactor using trymethylgalium (TMGa), trymethylalumunium (TMAl) and tridismethylaminiantimonat (TDMASb) as metalorganic sources. In the reactor we used a flow guide to obtain uniform layers. The effect of growth temperature and the V/III ratio on the structural properties, surface morphology, optical and electronic properties is presented. Penumbuhan GaSb dan AlGaSb dengan MOCVDSari. GaSb dam AlGaSb adalah semikonduktor paduan yang mempunyai selah energi yang sempit, dewasa ini sangat menarik mengingat penerapannya dalam optoelektronika di daerah inframerah yang dekat dan yang menengah. Perbandingan dari koefisien ionisasi dari lubang dan electron merupakan faktor yang menentukan dalam APD yang mempunyai respons yang cepat dan derau yang rendah. Dalam tulisan ini penulis melaporkan penumbujan dari GaSb dan AiGaSb dalam reactor MOCVD yang vertikal yang telah dibangun sendiri dengan menggunakan trimetilgalium (TMGa), trimetilaluminium (TMAI) dan trisdismetilaminoantimonat sebagai sumber-sumber metal-organik. Reaktor tersebut mempergunakan pemandu aliran untuk memperoleh lapisan dengan ketebalan yang uniform. Disini disajikan pengaruh dari temperature penumbuhan dan perbandingan V/III pada sifat-sifat struktur, morfologi permukaan, sifat-sifat optic dan sifat-sifat listriknya
Artelastokromen Suatu Diprenilpiranoflavon dan B-Resorsilaldehid dari Kayu Batang Artocarpus Lanceifolius
Get PDFAbstrak. Dua senyawa, yaitu artelactokromen (1), suatu diprenil piranoflavon, dan B-resorsilaldehid (2) telah ditemukan untuk pertama kalinya pada kayu batang tumbuhan Artocarpus lanceifolius Roxb. (Moraceae), suatu tumbuhan langka yang endemic untuk Indonesia dan dikenal dengan nama Keledang. Struktur molekul kedua senyawa tersebut telah ditetapkan berdasarkan data fisika dan spektroskopi (MS, 1H dan 13C NMR). Baik artelastokromen (1) maupun B-resorsilaldehid (2) tidak terlalu toksik terhadap nauplii udang Artemia salina Leach., masing-masing dengan LC50 298,2 dan 79,7 ug/mL. Artelastochromene a Diprenylphyranoflavone and Β-Resorcylaldehyde from the Wood Trunk of Artocarpus LanceifoliusAbstract. Two phenolic constituent, namely artelastochromene (1), a diprenyl pyranoflavone, and β-resorcylaldehyde (2) had been isolated from the wood trunk of Artocarpus lanceifolius Roxb. (Moraceae), an endemic species of Indonesia, locally known as Keledang. The structures of both compounds were elucidated based on physical and spectroscopic data (MS, 1H and 13C NMR). Both artelastochromene (1) and β-resorcylaldehyde (2) showed very slight toxic effect against shrimp nauplii Artemia salina Leach., LC50 298,2 and 79,7 μg/mL, respectively
Artoindonesianin D: a New Bioactive Pyranoflavone Derivative and Chaplashin from Artocarpus Maingayi
No full textSari. Suatu senyawa baru flavonoid terisoprenilasi turunan piranoflavon, yakni 5-hidroksisiklomorusin yang diberi nama artoindonesianin D (1), dan suatu senyawa turunan oksepinoflavon, yakni chaplasin (2), telah ditemukan untuk pertama kalinya, masing-masing pada kulit akar dan kayu akar tumbuhan Artocarpus maingayi King (Moraceae). Tumbuhan langka ini berasal dari Sumatera Barat dan endemik untuk Indonesia, serta dikernal dengan nama daerah Cubadak Utan. Struktur molekul kedua senyawa tersebut telah ditetapkan berdasarkan data fisika dan spektroskopi (MS, 1H dan 13C NMR). Artoindonesianin D (1) dan chaplasin (2) bersifat toksik terhadap nauplii udang Artemia salina Leach. Artoindonesianin D: a New Bioactive Pyranoflavone Derivative and Chaplashin from Artocarpus MaingayiAbstract. A new isoprenylated flavonoid, a pyranoflavone derivative 5'-hydroxycyclomorusin named artoindonesianin D (1), and an oxepinoflavone derivative chaplashin (2) were isolated for the first time, respectively from the root bark and root trunk of Artocarpus maingayi King. (Moraceae). This plant is locally known as Cubadak Utan, a rare species found in West Sumatera and endemic to Indonesia. The structure of both compounds were elucidated based on physical and spectroscopical data (MS, 1H and 13C NMR). Artoindonesianin D (1) and chaplashin (2) showed toxic effect against shrimp nauplii Artemia salina Leach