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"The explosive sensitivity upon the formation of supramolecular interaction between the nitro group of 3-nitro-1,2,4-triazol-5-one (NTO) and metal ions (Mn+ = Li+, Na+, Be2+ and Mg2+) has been investigated using Density FunctionalTheory at B3LYP/6-311++G** level of theory. The bond dissociation energy (BDE) of the C1?N6 trigger bond hasalso been discussed for the NTO monomer and the corresponding complexes. The interaction and bond dissociationenergy of the C6?N7 trigger bond follow the order of NTO-Be2+ > NTO-Mg2+ > NTO-Li+ > NTO-Na+ > NTOmonomer. The enhancement of the trigger bond dissociation energy in comparison with the NTO monomer correlateswell with the complex interaction energies, trigger bond length, and charge transfer. The analyses of electron densityshifts have shown that the electron density of the nitro group shifts toward the C1?N6 trigger bond upon the formationof the supramolecular interaction. As result, the trigger bond is strengthened and the sensitivity of NTO is reduced.Some of the calculated results agree with the experimental values.Sensitivitas Peledak Akibat Pembentukan Kompleks 3-Nitro-1,2,4-Triazol-5-One dan Ion Logam berdasarkanTeori Fungsional Kerapatan. Sensitivitas peledak yang terbentuk dari interaksi supramolekuler senyawa 3-nitro-1,2,4-triazol-5-one (NTO) dan ion logam (Mn+ = Li+, Na+, Be2+ and Mg2+) telah dipelajari menggunakan TeoriFungsional Kerapatan pada tingkatan teori B3LYP/6-311++G**. Energi pemutusan ikatan pada ikatan pemicu ledakan(C1-C6) juga telah dipelajari untuk monomer NTO dan senyawa kompleksnya. Energi ikat dan energi pemutusan ikatanmengikuti urutan: NTO-Be2+ > NTO-Mg2+ > NTO-Li+ > NTO-Na+ > monomer NTO. Peningkatan energi pemutusanikatan berbanding lurus dengan energi ikat, panjang ikatan pemicu ledakan dan transfer muatan. Analisis perubahankerapatan elektron menunjukkan bahwa kerapatan elektron gugus nitro berpindah pada ikatan C1-N6 ketika kompleksterbentuk. Hal ini menyebabkan ikatan pemicu ledakan menjadi semakin kuat sehingga sensitivitas NTO menjadiberkurang. Hasil kajian teoritis ini sesuai dengan hasil kajian eksperiemen."

"This research aims i) to determine the density profile and calculate the ground state energy of a quantum dot in twodimensions (2D) with a harmonic oscillator potential using orbital-free density functional theory, and ii) tounderstand the effect of the harmonic oscillator potential strength on the electron density profiles in the quantum dot.This study determines the total energy functional of the quantum dot that is a functional of the density that depends onlyon spatial variables. The total energy functional consists of three terms. The first term is the kinetic energy functional,which is the Thomas?Fermi approximation in this case. The second term is the external potential. The harmonicoscillator potential is used in this study. The last term is the electron?electron interactions described by the Coulombinteraction. The functional is formally solved to obtain the electron density as a function of spatial variables. Thisequation cannot be solved analytically, and thus a numerical method is used to determine the profile of the electrondensity. Using the electron density profiles, the ground state energy of the quantum dot in 2D can be calculated. Theground state energies obtained are 2.464, 22.26, 90.1957, 252.437, and 496.658 au for 2, 6, 12, 20, and 56 electrons,respectively. The highest electron density is localized close to the middle of the quantum dot. The density profilesdecrease with the increasing distance, and the lowest density is at the edge of the quantum dot. Generally, increasing theharmonic oscillator potential strength reduces the density profiles around the center of the quantum dot.Profil Kerapatan, Energi, dan Kuat Osilasi sebuah Kuantum Dot dalam Dua Dimensi dengan sebuah PotensialEksternal Osilator Harmonik menggunakan Fungsional Energi Bebas-orbital berdasarkan Teori Thomas?Fermi. Tujuan dari penelitian ini adalah: i) menentukan profil kerapatan dan menghitung energi keadaan dasar sebuahkuantum dot dalam dua dimensi (2D) dengan sebuah potensial osilator harmonik menggunakan teori fungsionalkerapatan bebas-orbital, dan ii) memahami efek dari kekuatan potensial osilator harmonik terhadap kerapatan elektrondalam kuantum dot. Penelitian ini menentukan fungsional energi total kuantum dot yang merupakan fungsional darikerapatan dan hanya bergantung pada variabel posisi. Fungsional energi total terdiri dari tiga suku. Suku pertama adalahfungsional energi kinetik yang dalam hal ini digunakan pendekatan Thomas?Fermi. Suku kedua adalah potensialeksternal. Dalam penelitian ini, potensial osilator harmonik yang digunakan. Suku terakhir adalah interaksi elektron?elektron yang dideskripsikan oleh interaksi Coulomb. Fungsional ini secara formal ditentukan solusinya untukmemperoleh kerapatan elektron sebagai fungsi posisi. Persamaan ini tidak dapat diselesaikan secara analitik, olehkarenanya, sebuah metode numerik digunakan untuk menentukan profil kerapatan elektron. Menggunakan profilkerapatan elektron yang diperoleh, energi keadaan dasar kuantum dot dalam 2D dapat dihitung. Nilai-nilai energikeadaan dasar yang diperoleh adalah 2,464; 22,26; 90,1957; 252,437; dan 496.658 au untuk masing-masing jumlahelektron 2, 6, 12, 20, dan 56. Kerapatan elektron tertinggi terlokalisasi pada bagian tengah kuantum dot. Profilkerapatan berkurang dengan bertambahnya jarak, dan kerapatan terendah berada pada ujung kuantum dot. Secaraumum, meningkatkan kuat osilasi akan menurunkan profil kerapatan elektron di sekitar bagian tengah kuantum dot."

"Chlorella pyrenoidosa (C. pyrenoidosa) contains Chlorella Growth Factor (CGF), which consists of protein and polysaccharides. CGF is located inside the nucleus of cells and is beneficial to humans as a food supplement, an immunity booster, and an antioxidant. CGF formation of C. pyrenoidosa is influenced by medium composition. C. pyrenoidosa INK was cultured in a modified basal medium (MBM) with various concentrations of Mg2+ (0.5, 1.0, and 1.5 g/L) and Fe2+ (3.5×10-4 and 5.0×10-4 g/L). The experiments were run and analyzed under a completely randomized design using a 2-L bottle with three replications.The results showed that MBM with 1.0 g/L of Mg2+ and 3.5×10-4 g/L of Fe2+ yielded the optimal growth curve for C. pyrenoidosa. Analysis of protein content was carried out using the Lowry method with a spectrophotometer at λ=750 nm, and the obtained results were 0.0974 mg/mL (extract) and 6.4097 mg/ml (supernatant). Furthermore, analysis of glucose content was carried out using the phenol sulfate method (λ = 490 nm), and the obtained results were 49.331 ppm (extract) and 1566.911 ppm (supernatant). Analysis of amino acids in CGF using liquid chromatography-mass spectrometry (LC-MS) indicated the presence of tyrosine, proline, glutamate, alanine, valine, tryptopan, phenylalanine, methionine, and leucine-isoleucine.

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Pengaruh Konsentrasi Mg2+ dan Fe2+ dalam Media Kultur terhadap Pembentukan CGF oleh Mikroalga Chlorella pyrenoidosa INK dan Analisis Asam Amino dengan Kromatografi Cair-Spektrofotometri Massa. Chlorella pyrenoidosa (C. pyrenoidosa ) mengandung Chlorella Growth Factor (CGF), yang terdiri dari protein dan polisakarida. CGF terletak di dalam inti sel dan bermanfaat bagi manusia sebagai suplemen makanan, booster imunitas, dan antioksidan. Pembentukan CGF oleh C. pyrenoidosa dipengaruhi oleh komposisi medium. C. pyrenoidosa INK dikultur dalam media basal dimodifikasi (MBM) dengan berbagai konsentrasi Mg2+ (0,5, 1,0, dan 1,5 g/L) dan Fe2+ (3,5×10-4 dan 5,0×10-4 g/L). Percobaan dilakukan menggunakan rancangan acak lengkap dalam botol 2L dengan tiga kali pengulangan.Hasil penelitian menunjukkan bahwa MBM mengandung Mg2+ 1.0 g/L dan Fe2+ 3.5×10-4 g/L menghasilkan kurva pertumbuhan C. pyrenoidosa yang optimal. Analisis kandungan protein dilakukan dengan metode Lowry menggunakan spektrofotometer pada λ=750 nm, menghasilkan 0,0974 mg/mL (ekstrak) dan 6,4097 mg/mL (supernatan). Selanjutnya, analisis kadar glukosa dilakukan dengan metode fenol sulfat (λ=490 nm), hasil yang diperoleh 49,331 ppm (ekstrak) dan 1566,911 ppm (supernatan). Analisis asam amino dalam CGF menggunakan spektrometri massa kromatografi cair (KC-SM) menunjukkan adanya tirosin, prolin, asam glutamat, alanin, valin, triptopan, fenilalanin, metionin, dan leusin-isoleusin."

"Pembentukan 8-Hidroksi-2′-Deoksiguanosin (8-OHdG) dalam Calf thymus DNA yang Disebabkan dari Reaksi 2′-Deoksiguanosin dengan Senyawa Propil Galat dan 2,6-Di-Tert-Butil-p-Benzoquinon secara In Vitro. Kerusakan oksidatif DNA yang disebabkan oleh propil galat (PG) dan 2,6-di-tert-butil-p-benzoquinon (BHT-quinon, metabolit BHT), dianalisis dari pembentukan DNA adduct, 8-hidroksi-2’-deoksiguanosin (8-OHdG), terhadap calf thymus DNA dan basa tunggal DNA, 2′-deoksiguanosin (dG) secara in vitro. PG dengan dimediasi oleh CuCl2 menyebabkan peningkatan 8-OHdG terhadap calf thymus DNA sebesar 9,17 kali lebih besar dibandingkan terhadap kontrol (DNA tanpa perlakuan). Dengan adanya CuCl2 pada konsentrasi 1,28 x10-5 M, rasio pembentukan 8-OHdG dari hasil interaksi antara dG dengan PG pada berbagai variasi konsentrasi (20-150 ppm) berkisar antara 75,50-312,06 8-OHdG terhadap 105 dG. Pembentukan 8-OHdG tersebut, meningkat dengan bertambahnya konsentrasi PG dari 20-80 ppm, kemudian mulai stabil dengan bertambahnya konsentrasi PG diatas 80 ppm. Sementara itu, BHT-quinon dengan adanya CuCl2 menyebabkan peningkatan 8-OHdG terhadap Calf thymus DNA sebesar 0,05 kali dibandingkan kontrol (DNA tanpa perlakuan). Analisis menggunakan LC-MS/MS dilakukan untuk mengidentifikasi 8-OHdG, dengan puncak induk (M+. + 1) 284 dan memiliki dua fragmen utama m/z 167,9 dan m/z 139,9.

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Oxidative DNA damage caused by propyl gallate (PG) and 2,6-di-tert-butyl-p-benzoquinone (BHT-quinone, a metabolite of butylated hydroxytoluene (BHT)) was analyzed from the 8-hydroxy-2′-deoxyguanosine (8-OHdG) formation in calf thymus DNA and DNA base, 2′-deoxyguanosine (dG). PG in the presence of CuCl2 increased the 8-OHdG formation in calf thymus DNA by around 9.17 times as compared to the control (untreated DNA). In the presence of CuCl2 at 1.28×10-5 M, the 8-OHdG per dG ratio resulting from the reaction of dG with PG at various concentrations (20-150 ppm) ranged from 75.50 to 312.06 8-OHdG per 105 dG. The 8-OHdG formation increased when the PG concentration was increased from 20 ppm to 80 ppm, and then, it began to plateau around 80 ppm. On the other hand, BHT-quinone increased the formation of 8-OHdG in the presence of CuCl2 by 0.05 times as compared to the control (untreated DNA). LC-MS/MS analysis was used to identify the molecular structure of 8-OHdG, which had a base peak (M+. + 1) at m/z = 284 and two main fragments at m/z = 167.9 and m/z = 139.9."

"Genes related to starch synthesis and the metabolism contribute to a variety of physicochemical properties thatdetermine the eating/cooking qualities of rice. Our previous study suggested that a set of molecular markers was able toestimate the eating quality of japonica rice. The present study reports the genetic diversity of 22 japonica rice varietiesbased on markers corresponding to starch synthesizing genes. The mean of the polymorphic information content (PIC:0.135) value and the diversity index (0.171) indicated a low genetic diversity in these varieties. The phylogenetic treeclearly demonstrated three main clusters: 1) cluster I contained seven varieties with similar physicochemical properties;2) cluster II only showed a Japanese variety, Koshihikari, and 3) cluster III included the most Korean varieties (14varieties). This phylogenetic analysis did not completely represent the physicochemical properties differentiation of thejaponica varieties, although it did reveal an initial clue to the close relationship between Korean rice and the Japaneseand Chinese varieties. Notably, these markers were also able to identify a premium japonica rice. The molecularmarkers and information concerning the genetic relationship would be useful in improving the japonica rice along withits starch quality of in breeding program.Keragaman Genetik Padi Japonica berdasarkan Marka terkait Gen Sintesis Pati. Gen terkait sintesis danmetabolism pati berkontribusi pada berbagai sifat fisiko-kimia yang menentukan mutu rasa dan hasil masak (cooking)beras. Penelitian sebelumnya menunjukkan bahwa satu set marka molekuler mampu memprediksi mutu rasa berasjaponica. Pada studi ini dilaporka keragaman genetik 22 varietas padi japonica berdasarkan marka untuk gen-genpensintesis pati. Rata-rata nilai polymorphic information content (PIC:0,135) dan indeks keragaman (0,171)menunjukkan keragaman genetik yang rendah dalam varietas padi ini. Pohon filogenetik menunjukkan tiga kelompokutama yang dibentuk: 1) klaster I terdiri dari tujuh varietas dengan sifat fisikokimia yang mirip; 2) klaster II hanyaterdiri dari verietas premium Jepang, Koshihikari, dan 3) klaster III mengelompokkan sebagian besar varietas Korea (14varietas). Analisis filogenetik ini belum sepenuhnya menggambarkan diferensiasi varietas japonica berdasarkan sifatfisiko-kimia, namun hasil ini mengungkapkan petunjuk awal korelasi yang erat antara padi Korea dengan varietasJepang dan Cina. Marka-marka tersebut juga mampu mengidentifikasi beras premium japonica. Marka molekuler daninformasi kekerabatan genetik ini akan berguna dalam membantu mengembangkan padi japonica terkait dengan mutupati dalam program pemuliaan"

"Bacterial leaf blight (BLB) is one of the major diseases in rice caused by Xanthomonas oryzae pv. oryzae. This studyaimed to identify and analyze the genetic diversity of 18 BLB isolates that consist of 7 races and 11 haplotypes fromvarious locations in Indonesia. The genetic diversity analysis was conducted on the basis of the VNTR (VariableNumber of Tandem Repeat) markers and the avrxa7 gene marker. The banding pattern of the amplification product wasmade into binary data as input for the construction of a dendogram. Based on the dendogram, three X. oryzae pv. oryzaegenotype groups with different virulence levels were formed. The VII (IXO80_021) race of X. oryzae pv. oryzaegenotype group I and the VIII-A (IXO 80_024) race of genotype group II were avirulent, whereas the races andhaplotypes of genotype group III were virulent.Keragaman Genetik Core Collection Isolat Bacterial Leaf Blight (Xanthomonas oryzae pv. oryzae) Indonesiaberdasarkan Marka Molekular VNTR dan avrXa7. Bacterial leaf blight (BLB) adalah salah satu penyakit utama padiyang disebabkan oleh bakteri pathogen Xanthomonas oryzae pv. oryzae. Penelitian ini bertujuan untuk mengidentifikasidan menganalisis keragaman genetik 18 isolat isolates yang terdiri dari 7 ras dan 11 haplotipe yang berasal daribeberapa lokasi koleksi di Indonesia. Analisis keragaman genetik dilakukan menggunakan marka VNTR (VariableNumber of Tandem Repeat) dan marka gen avrxa7. Pola pita DNA hasil amplifikasi digunakan sebagai data input bineruntuk membuat dendogram keragaman. Berdasarkan dendogram tersebut, terdapat tiga kelompok genotipe X. oryzaepv. oryzae dengan tingkat virulensi yang berbeda. Ras VII (IXO80_021) yang termasuk dalam kelompok I dan RasVIII-A (IXO 80_024) yang termasuk dalam kelompok II merupakan ras BLB yang tidak virulen. Sedangkan kelompokIII merupakan kelompok ras dan haplotipe yang bersifat virulen."

"Two-dimensional photonic crystal structures not only confine light and guide waves laterally but also reflect light in thenormal direction due to a slow Bloch mode effect. However, evidence of the utilization of this structure as a mirror isrequired. Therefore, in this work, a simulation was made and experimental results were obtained to prove that there wasan increase in the intensity of reflected CdSe colloidal quantum dots emission in the normal direction when a 2Dphotonic crystal structure was used. A thin TiO2 film was shaped into a two-dimensional photonic crystal structure usinga simple sol-gel and polystyrene-mask-etching procedure. This structure was then placed on top of the thin CdSequantum dots film layer. The emission of quantum dots onto the two-dimensional photonic crystal structure wascompared to quantum dots emission onto a flat, thin TiO2 film. An increase in the quantum dots emission of up to 105%was in the presence of the two-dimensional photonic crystal structure. This finding is very useful for photonic deviceapplications, such as light-emitting diodes, laser systems and bio-tagging detection systems.Studi Simulasi dan Eksperimen Struktur Kristal Fotonik Dua Dimensi sebagai Pemantul Emisi Kuantum DotMasalah Arah Normal. Kristal fotonika dua dimensi tidak hanya dapat mengukung cahaya dan memandu gelombangke arah sisi horizontal, tapi juga mampu memantulkan cahaya ke arah normal dikarenakan efek moda slow Bloch .Namun bukti tentang penggunaan stuktur ini masih dibutuhkan. Untuk itu dalam penelitian ini hasil simulasi danpercobaan telah didapatkan untuk membuktikan bahwa terjadi peningkatan pantulan emisi CdSe kuantum dot colloidpada arah normal saat kristal fotonika dua dimensi digunakan. Sebuah lapisan tipis TiO2 dibentuk menjadi kristalfotonika dua dimensi denga menggunakan teknik sol-gel yang sederhana dan etching dengan menggunakanpolystyrene. Struktur ini diletakkan di atas lapisan kuantum dot CdSe. Emisi dari kuantum dot di atas kristal fotonikadua dimensi dibandingkan dengan emisi kuantum dot di atas lapisan tipis dan datar TiO2. Peningkatan emisi kuantumdot hingga mencapai 105% berkat kehadiran kristal fotonika dua dimensi. Hasil ini sangat berguna untuk aplikasidivais fotonika seperti LED, sistem laser dan sisten detesi bio-tagging."

"ABSTRAKAmmonia and phosphorus have been recognized as the cause of eutrophication in surface water. Chuat Man Canal is faced with water quality degradation problem due to the high concentrations of ammonia and total phosphorus in the water body that makes it unsuitable for fish ponds. Removal of ammonia and phosphorus by the adsorption process is simple and not requires chemical use. In addition, ammonia is well adsorbed by activated carbon and zeolite while phosphorus is adsorbed by zeolite. This research used zeolite and activated carbon for the adsorption of ammonia and total phosphorus. The results of laboratory experiments at 30 °C 200 rpm 60 minutes, revealed that adsorption of ammonia using zeolite correlated with Freundlich isotherm (R2 = 0.9031). For ammonia adsorption using activated carbon, it correlated with Langmuir (R2 = 0.9596) and Freundlich (R2 = 0.9113) isotherms, respectively. For field experiment, 9 zeolite and activated carbon adsorbent pads with ratio of 1.6:1 by weight were placed across the canal sections. Each pad had 2 openings and each opening contained its adsorbent volume of 1.0 × 0.015 × 0.6 m3 (width × length × height). The front opening contained 5 kg of activated carbon while the back part contained 8 kg of zeolite. During the study, water flow velocity at surface of water was ranged from 0.022 - 0.027 m/s. Concentration of ammonia in influent and effluent was ranged from 1.755- 8.817 mg/L and 1.473-7.063 mg/L, respectively while that for total phosphorus was ranged from 0.045 - 0.095 mg/L and 0.042 - 0.089 mg/L, respectively. The maximum removal efficiency occurred 20 and 43 minutes after installation of the adsorption pads which were 6.73% for total phosphorus and 23.17% for ammonia, respectively."

"Biofilm is an aggregate of consortium bacteria that adhere to each other on a surface. It is usually protected by the exopolysaccharide layer. Various invasive medical procedures, such as catheterization, endotracheal tube installation, and contact lens utilization, are vulnerable to biofilm infection. The National Institute of Health (NIH) estimates 65% of all microbial infections are caused by biofilm. Periplasmic α-amylase (MalS) is an enzyme that hydrolyzes α-1, 4- glicosidic bond in glycogen, starch, and others related polysaccharides in periplasmic space. Another protein called hemolysin-α (HlyA) is a secretion signal protein on C terminal of particular peptide in gram negative bacteria. We proposed a novel recombinant plasmid expressing α-amylase and hemolysin-α fusion in pSB1C3 which is cloned into E.coli to enable α-amylase excretion to extracellular for degrading biofilm polysaccharides content, as in starch agar. Microtiter assay was performed to analyze the reduction percentage of biofilm by adding recombinant E.coli into media. This system is more effective in degrading biofilm from gram positive bacteria i.e.: Bacillus substilis (30.21%) and Staphylococcus aureus (24.20%), and less effective degrading biofilm of gram negative i.e.: Vibrio cholera (5.30%), Pseudomonas aeruginosa (8.50%), Klebsiella pneumonia (6.75%) and E. coli (-0.6%). Gram positive bacteria have a thick layer of peptidoglycan, causing the enzyme to work more effectively in degrading polysaccharides."