Makara Journal of Science
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PROPERTIES OF HIGH-ORDER HARMONIC GENERATION SIGNALS FROM SWITCHED-OFF ALIGNED MOLECULES
No full textA quantum theory of intense-field pump-probe experiments proposed recently, which successfully described the highorder harmonic generation (HHG) signals of adiabatic and non-adiabatic aligned molecules, is applied here to investigate the HHG signals from molecules aligned by using switched-off schema. The results are presented in the two externally available control parameters: the delay time, td, between the pump and the probe pulse, and the relative angle, α, between their polarizations. To provide more succinct and clearer information of the beats involved in the signal, the signal is also presented in the frequency domain. The results show that the HHG signals of switched-off aligned molecules mimic those of the adiabatic and non adiabatic aligned molecules, and therefore, it can be used to determine some molecular properties, as powerful as non-adiabatic signal. In addition, the HHG signals of switched-off aligned molecules also have benefit, which is it gives a greater modulation depth
PENURUNAN NOISE FIGURE PERFORMANCE (FN) PADA HETEROJUNCTION BIPOLAR TRANSISTOR SI/SI 1-X GEX BERDASARKAN PENGATURAN STRIPE EMITTER AREA (AE) DAN FRACTION MOLE (X)
No full textReduction of Noise Figure (Fn) on Bipolar Heterojunction Si/Si1-x Gex based on Arrangements Stripe Emitter Area (Ae) and Mole Fraction (x). This paper investigates the influence of stripe emitter area (Ae) and fraction mole (x) concerning about noise figure performance (FN) at HBT SiGe. It takes the second generation of HBT SiGe IBM with Ae; 0.18 x 10 μm2 developed as its model. When the alterations of Ae are from 0.18 x 10 μm2, 0.12 x 10 μm2 and 0.09 x 10 μm2, at the same time the fraction mole (x) is raised twice, it makes positive relation to RB and β parameter, but negative relation to RC, fT, and fmax parameter. A model of HBT SiGe with x: 0.1 and Ae: 0.18 x 10 μm2 produces 0.57dB of Fn minimum, the value is less than the other of which has 0.64dB for Ae: 0.12 x 10 μm2 and 0.69 dB for Ae: 0.09 x 10. Then if fraction mole(x) is reduced for 50%, it causes nonlinear Fn raising which are 77%, 79% and 89% from the previous value. Noise figure (Fn) had a negative relationship with emitter stripe area (Ae), whereas the mole fraction (x) has a positive relationship; so the noise figure (Fn) can be made low by minimizing emitter stripe area (Ae) and raise the mole fraction (x)
Xanthomonas oryzae pv. oryzae BAKTERI PENYEBAB HAWAR DAUN PADA PADI: ISOLASI, KARAKTERISASI, DAN TELAAH MUTAGENESIS DENGAN TRANSPOSON
No full textXanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis. X. oryzae pv. oryzae (Xoo) causes bacterial leaf blight (BLB) of rice (Oryza sativa L.), a major disease that constrains production of the staple crop in many countries of the world. Identification of X. oryzae pv. oryzae (Xoo) was conducted based on the disease symptoms, pathogenicity, morphological, physiological, and genetic characteristics of bacterial cultures isolated from the infected plants. Fifty bacterial isolates predicted as Xoo have been successfully isolated. They are aerobic, rod shaped, and Gram negative bacteria. The isolates were evaluated for their hypersensitivity in tobacco and pathogenicity in rice plant. Fifty isolates induced hypersensitive reaction in tobacco and showed pathogenicity symptom in rice in different length. Based on physiological test, hypersensitivity and pathogenicity reactions, three bacterial isolates strongly predicted as Xoo, i.e. STG21, STG42, and STG46, were non indole formation, non pigment fluorescent, hydrolyzed casein, catalase activity positive, but negative oxidase. Partial sequencing of 16S rRNA genes of STG21 and STG42 showed 80% and 82% homology with X. oryzae, respectively, while STG46 showed 84% homology with X. campestris. Mini-Tn5 transposon mutagenesis of STG21 generated one of the mutants (M5) lossed it’s ability to induce hypersensitive reaction in tobacco plant and deficient in pathogenicity on rice. The lesion length of rice leaf caused by the mutant M5 decreased up to 80%.Keywords: bacterial leaf blight, characterization, isolation, transposon mutagenesis, Xanthomonas oryzae pv. oryza
PURIFICATION AND CARBOHYDRATE ANALYSIS OF RECOMBINANT HUMAN ERYTHROPOIETIN EXPRESSED IN YEAST SYSTEM Pichia pastoris
No full textFor clinical purposes, pure protein and identification of carbohydrate structure from recombinant erythropoietin are needed. Purification was done by Immobilized Metal Affinity Chromatography (IMAC) column charged with Ni2+ (His-Trap affinity chromatography) and continued with gel filtration chromatography column to get purer protein. The carbohydrate group which is oligosaccharide from the resulting pure protein then can be recognized by using N- and O-glycosidase. Pure oligosaccharide was hydrolyzed to produce various monosaccharide through incubation with 4 N HCl in 100 oC temperature for 6 hours and the result was applied on High Performance Liquid Chromatography (HPLC) column to learn the composition of its monosaccharide.Keywords: EPO, gel filtration chromatography, His-Trap affinity chromatography, monosaccharid
DISOLUSI MIKROENKAPSULASI KURKUMIN TERSALUT GEL KITOSAN-ALGINAT-GLUTARALDEHIDA
No full textDissolution of Curcumin Microencapsulation Coated by Chitosan-Alginate-Glutaraldehide. In vitro dissolution of curcumin coated by chitosan-alginate gel in its optimum condition was studied. The maceration process using 17.08% ethanol yields and the content of the curcumin in the extract detected by visible spectrophotometry λ 430 nm is found to be 10.30 %. Its optimum condition was obtained using response surface method at concentrations ratio of alginate 0.62% (b/v) and glutaraldehide 4.63% (v/v) , respectively, where the chitosan concentration was fixed (1.75% [b/v]). The dissolution assay was done at 37 oC, at 100 rpm of stirring rate in 8 hours. Aliquots were taken at 15, 30, 45, 60, 90, 120, 150, 180, 240, 300, 360, 420, 480 minutes. Absorbance of the Aliquots was measured at λ 430 nm. The curcumin released has the best linear correlation to the first order reaction with released constant, k = 2.24 10-3 minute-1 while it’s half live is t1/2 = 5.16 hours. Release curcumin was determined mainly by diffusion mechanism. Compared to the result based on Fick model, the one of Higuchi model is better in agreement in reproducing the released data. Keywords: chitosan-alginate-glutaraldehide, curcumin, diffusion-dissolution, microencapsulatio
KERAGAMAN GENETIK PANDAN ASAL JAWA BARAT BERDASARKAN PENANDA INTER SIMPLE SEQUENCE REPEAT
No full textGenetic Diversity of Pandanus from West Java based on ISSR Markers. The genetic diversity of 10 species of Pandanus from West Java was examined using inter simple sequence repeat (ISSR) technique. Samples were collected from different localities in West Java. Two primers (ISSR2 and ISSR7) were selected as reliable amplifying ISSR markers. The two primers amplified 19 band position, with amplification size ranged from 200 to 1500 bp. Genetic distance for samples ranged from 0.267 to 0.957. Genetic distance was high (0.957) between P. pseudolais and P. spinistigmaticus, and between P. kurzii and P. pseudolais, where as genetic distance was low (0.267) between P. scabrifolius and P. bidur
KOPOLIMERISASI CANGKOK (GRAFT COPOLYMERIZATION) N-ISOPROPILAKRILAMIDA PADA FILM SELULOSA YANG DIINDUKSI OLEH SINAR ULTRAVIOLET DAN KARAKTERISASINYA
No full textGraft Copolymerization of N-Isopropylacrylamide on Cellulose Film Induced by UV-Irradiation and its Characterization. The effect of monomer and initiator concentrations, graft polymerization temperature, polymerization system and organic solvents on photografting of N-isopropylacrylamide on regenerated cellulose films (thickness = 20 µm) in UV irradiation were investigated. The higher percentage of grafting was afforded for the system with the higher monomer and initiator concentration. The photografting initiated even in the system at 30 °C by using a longer irradiation time. It was found that the maximum percentage of grafting was attained at 2.5 (%Vol) of methanol/acetone in the mixed solvent. The resulting NIPAAm-grafted cellulose films were characterized by attenuated total-reflection IR spectroscopy, showed a peak at 1640 and 1550 cm-1 due to the amide groups of the NIPAAm-grafted chains. According to scanning electron microscopy characterization, the grafted chains was found to distribute inside the film sample even in the grafted films with lower percentage of grafting. The grafted samples showing a temperatureresponsive character swelling and shrinking in water at 5 °C and 50 °C, respectively. Keywords: cellulose film, N-isopropylacrylamide, organic solvents, photografting, temperature-responsive charact  
PENYISIHAN LOGAM BERAT DARI LIMBAH CAIR LABORATORIUM DENGAN METODE PRESIPITASI DAN ADSORPSI
No full textRemoval of Heavy Metals from Liquid Laboratory Waste Using Precipitation and Adsorption Methods. Liquid laboratory waste (such as residue of chemical oxygen demand/COD analysis) contains high concentration of heavy metals (mercury/Hg, silver/Ag and chrome/Cr) and has a high potential to pollute the environment. The liquid waste generated by laboratories is generally in small quantity, but it is extremely toxic. It is urgently in need to find out an appropriate method to reduce the problems according to the liquid waste characteristics. In this research work, precipitation and adsorption methods were evaluated to remove Hg, Ag, and Cr from liquid laboratory waste, covering determination of optimum process conditions, levels of removal and achievable treated waste quality. Results showed that a Cr removal of 97% was obtained by pH 10, and Hg and Ag removals of 97-99% were reached by pH 12. Although heavy metals removals using precipitation was very significant, but the concentration of heavy metals in the treated waste was still high (0.73-2.62 mg/L) and need for further treatment. Applying activated carbon adsorption for further treatment of the effluent reduced dissolved heavy metals to 0-0.05 mg/L, depending on the type of heavy metals as well as the type and dosing of activated carbon. Keywords: activated carbon adsorption, heavy metals removal, liquid laboratory waste, precipitatio
PENINGKATAN UNJUK KERJA HIDROLISIS ENZIMATIK JERAMI PADI MENGGUNAKAN CAMPURAN SELULASE KASAR DARI Trichoderma reesei DAN Aspergillus niger
No full textIncreasing the Performance of Enzymatic Hydrolysis of Rice Straw Using Mixed Crude Cellulases from Trichoderma reesei and Aspergillus niger. The objective of this work is to compare the effectiveness of mixed crude enzyme cellulase from T. reesei and A. niger with commercial enzyme from A. niger, and to investigate effect of enzyme to substrate ratio to performance of enzymatic hydrolysis of rice straw. The commercial enzyme from Fluka Biochemica was used, and crude enzyme were prepared by solid fermentation with simple media. Before hydrolized, the rice straw was grinded and sieved and then heated at 85 oC with 2% sodium hydroxide for six hours. Hydrolysis was conducted in 300 mL beaker flask equipped with mechanical stirrer. Samples were analyzed by dinitrosalicylic acid method and measured by spectrophotometer. Both of commercial and mixed crude enzyme show that, the higher enzyme to substrate ratio was higher the glucose concentration obtained. However, ratio of glucose obtained to enzyme used become smaller. The mixture of crude enzyme from T. reesesi dan A. niger that produced in this work was two fold more effective to hydrolyze rice straw than using cellulase enzyme of A. niger from Fluka Biochemika.Keywords: rice straw, cellulase, hydrolysis, A. niger, T. reese
EVALUASI SKEMA WATERMARKING CITRA BERBASIS SINGULAR VALUE DECOMPOSITION, KUANTISASI DITHER, DAN DETEKSI SISI
No full textEvaluation of Singular Value Decomposition based Digital Image Watermarking with Dither Quantization and Edge Detection. The use of singular value decomposition (SVD) in watermarking area has been developed by many researchers. In this paper, we describe our evaluation result against an SVD based watermarking scheme with Dither quantization and edge detection proposed by Mohan et al. As an evaluation benchmark, we use StirMark to produce modified images by various image attacks. The extracted watermarks from these images were compared with the original watermark by calculating its bit correlation ratio (BCR). The result shows that the scheme is robust against JPEG compression, rotation, scaling, and PSNR attack. The scheme is also quite robust to some extents against remove-line attack and cropping