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"The magnet is one of the main components of a cyclotron, used to form a circular particle beam trajectories and to provide focusing of the beam. To support the mastery of 13-MeV proton cyclotron technologies, cyclotron magnet design must be done to satisfy cyclotron magnet requirements. This research was conducted by studying important parameters in designing the cyclotron magnet which is then used to determine the design requirements. The magnet design was based on the results of a 3D simulation using Opera 3D software. Opera 3D is a software developed by Cobham plc to solve physical problems in 3D such as magnetostatic using finite element methods. The simulation started by drawing a 3D model of the magnet using a modeler, followed by magnetic field calculations by Tosca module in the Opera 3D software. Simulation results were analyzed with the Genspeo software to determine whether the parameters of the cyclotron magnet have met design requirements. The results indicate that the magnet design satisfied the cyclotron magnet design requirement, that B in the median plane of the magnetic pole approached the isochronous curve, providing axial and radial focusing beam, crossing the resonance line at vr = 1 when the particle energy is low and the particle energy is more than 13 MeV, and lead to small enough phase shift of about 13°. The dimension of the cyclotron magnet is 1.96 m × 1.30 m × 1.21 m; its weight is 17.3 ton; its coil current is 88,024 ampere-turn; its center magnetic field is 1.27479 T; its maximum magnetic field is 1.942116 T; its minimum magnetic field is 0.7689 T; its valley gap is 120 mm; its hill gaps are 40 to 50.78 mm; and its hill angles are 35° to 44°.to 44°"

"Virus Influenza merupakan virus patogen yang menular dan pendemik terhadap manusia. Deteksi NA sebagai salah satu enzim dalam virus influenza menggunakan reaksi inhibisi oleh Zanamivir, dilakukan secara elektrokimia dengan teknik voltametri siklik menggunakan elektroda Pt-BDD dan PtNPs-BDD sebagai elektroda kerja. Deteksi NA dilakukan dengan mengamati perubahan respon elektrokimia zanamivir dalam buffer fosfat saat terdapat NA atau tidak. Deteksi NA dikembangkan dengan sistem magnetic beads dan strip test. Kurva kalibrasi linier pengukuran zanamivir berdasarkan puncak arus oksidasi diperoleh pada rentang kosentrasi 1,5x10-6 M – 1,5x10-3 M pada elektroda Pt-BDD dan rentang konsentrasi 1,5x10-7 M – 1,5x10-4 M pada elektroda PtNPs-BDD. Limit deteksi Zanamivir pada Pt-BDD sebesar 2,997 x 10-7 M untuk dan 5, 64 x 10-8 M pada elektroda PtNPs-BDD. Pt-BDD dan PtNPs-BDD kemudian digunakan pada aplikasi sebagai sensor Zanamivir, konsentrasi Zanamivir 2x10-5 M dapat dengan tepat menginhibisi 20 mU Neuraminidase dengan batas deteksi 4,6667 mU untuk Pt-BDD dan 2,833 mU untuk PtNPs-BDD. Kondisi optimum pengukuran adalah pada pH 6,8 dengan waktu inkubasi 25 menit. Selektivitas sensor diuji dengan penambahan 0,01 mg/mL Interferensi yaitu mucin, glukosa, dan α-amilase, terjadi penurunan respon arus oksidasi namun tidak signifikan, mengindikasikan sensor yang dikembangkan cukup menjanjikan.

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Influenza viruses are pathogenic viruses and pandemic infectious to human body. In this work, detection method of Neuraminidase as influenza virus enzyme was developed by electrochemical method with cyclic voltametry method using Pt-BDD and PtNPs-BDD as working electrode. The detection method was developed based on the difference of electrochemical responses of zanamivir in the presence and the absence of NA in phosphate buffer solution. Detection of NA developed on magnetic beads and strip test. Linier calibration curve of zanamivir concentration based on oxidation peak current obtained in the range 1,5x10-6 M - 1,5x10-3 M on Pt-BDD electrode and 1,5x10-7 M - 1,5x10-4 M on PtNPs-BDD electrode. Limit detection (LOD) of Zanamivir on Pt-BDD electrode 2,997 x 10-7 M and 5, 64 x 10-8 M on PtNPs-BDD electrode. Application of Pt-BDD and PtNPs-BDD as sensor for Neuraminidase showed that the maximum concentration of Neuraminidase can be inhibited by 1,5x10-5M zanamivir was 20 mU. LOD was 4,6667 mU for Pt-BDD and 2,833 mU for PtNPs-BDD. The optimum pH for the inhibition was 6.8 with incubation time of 25 minutes. Selectivity of the sensor was examined with the presence of mucin, glucose and α-amilase with a concentration of 0,01 mg/mL, decrease in the oxidation current response but not significant, suggesting that the sensors is promising to be applied."

"Hasil penelitian terdahulu menunjukkan bahwa ekstrak daun dalam pelarut air dan batang beligo fraksi etil asetat memiliki aktivitas antioksidan.Pada penelitian ini, dilakukan uji aktivitas antioksidan ekstrak buah, biji, dan kulit beligo dan ditentukan bagian buah beligo yang memiliki daya antioksidan tertinggi. Pengujian dilakukan terhadap ekstrak kulit, daging buah,atau dalam pelarut etanol, etil asetat, nbutanol, atau air. Aktivitas antioksidan ditentukan dengan menentukan nilai IC50 menggunakan metode DPPH. Hasil penelitian menunjukkan nilai IC50 terendah diperoleh pada fraksi etil asetat ekstrak kulit beligo dengan nilai 1428,80 ppm. Hasil optimasi pemisahan dengan KLT dari ekstrak kulit buah beligo fraksi teraktif menunjukkan bahwa pemisahan yang terbaik diperoleh menggunakan eluen campuran n- heksana dengan etil asetat dengan perbandingan 7:3.

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Previous study showed that leaves extract in water and stems extract in ethyl acetate from beligo have antioxidant activity. In this study, the thigest antioxidant activity of beligo fruits, seeds, and rinds extracts were determined. The assays were carried out of skin, pulp, seeds or in beligo extracts in ethyl acetate, n-butanol, and water. The antioxidant activities were determined by determine the IC50 values using DPPH method.

The result showed that the lowest IC50 values obtained in fractions of ethyl acetate beligo extract of the rind with a value of 1428,80 ppm. The optimization with TLC separation the most active fraction of beligo rind extract revealed that the best separation was obtained using a mixture of n hexane with ethyl acetate in ratio (7:3) as eluent."

"Zeolite modified electrode telah berhasil disintesis dan diaplikasikan sebagaisensor gas amonia. Pertama-tama, kuarsa dilapisi dengan lem perak dan emasguna meningkatkan sifat perekat antara kuarsa dan zeolit. Zeolit ZSM-5 dan NaYkemudian secara berturut-turut dilapisi di atas permukaan kuarsa dengan metodespin coating. Modifikasi kation logam Cu2 dilakukan dengan teknik ion exchangedalam rangka meningkatkan sensitivitas sensor. Komposit hibrida zeolit diujisebagai sensor gas amonia diukur dengan Electrochemical ImpedanceSpectroscopy EIS pada rentang frekuensi 1 MHz hingga 100 Hz untuk rentangkonsentrasi amonia dari 0-500 ppm. Cu/NaY/ZSM-5/IDC bekerja secara optimalpada frekuensi 100 Hz dengan R2 = 0,9696. Keberadaan uap air dan gas karbondioksida meningkatkan nilai konduktivitas material, tetapi tidak memberikanpengaruh yang berarti terhadap sensitivitas sensor. Dengan demikian, dapatdisimpulkan bahwa komposit hibrida zeolit memiliki sensitivitas yang baiksebagai sensor amonia pada lingkungan sekitar.

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Zeolite modified electrode has been successfully synthesized and applied asammonia gas sensor. First, quartz was coated with silver glue and gold Au forincreasing adhesive properties between quartz and zeolites. Each of ZSM 5 zeoliteand NaY zeolite was coated on the surface of the quartz by spin coating method.Modification with metal cation Cu2 was carried out by using ion exchangetechnique, in order to improve the sensitivity of the sensor. Zeolite hybridcomposite was tested as ammonia gas sensor using Electrochemical ImpedanceSpectroscopy EIS in the frequency range of 1 MHz to 100 Hz with ammoniaconcentration range between 0 500 ppm. Cu NaY ZSM 5 IDC worked optimallyat the frequency of 100 Hz with R2 0.9696. The presence of water vapor andcarbon dioxide gas increases the conductivity of the material, but it has nosignificant effect to the sensitivity of the sensor. Thus, it can be concluded thatzeolite hybrid composite has sensitivity as a good ammonia gas sensor in theambient environment."

"Senyawa bioaktif Annonaceous acetogenin yang berasal dari tanaman sirsak (Annona muricata) ditemukan memiliki sifat sitotoksik dan antitumor secara spesifik terhadap beberapa jenis kanker, di antaranya adalah kanker usus, payudara, paru-paru, pankreas, dan ginjal. Acetogenin yang diperoleh dari proses ekstraksi daun sirsak, kemudian dianalisis secara kualitatif (TLC, BST, FTIR) dan kuantitatif (Spektrofotometri UV-Vis). Hasil ekstraksi terbagi menjadi lima fraksi yang diberi nama F001, F002, F003, F0004, F005, dan diduga bahwa F005 mengandung acetogenin. F005 kemudian diisolasi dan terpisah ke dalam 13 bagian dengan bagian 6-9 mengandung acetogenin. Analisis kuantitatif dilakukan dengan menghitung kandungan gugus lakton acetogenin, menggunakan senyawa standar andrographolida. Penggunaan andrographolida sebagai senyawa standar dikarenakan senyawa murni acetogenin sulit didapat, dan andrographolida memiliki gugus lakton yang hampir sama dengan acetogenin, selain itu pada daun sirsak hanya acetogenin yang memiliki gugus lakton sehingga penentuan berdasarkan gugus lakton dapat dilakukan. Berdasarkan analisis kualitatif, hasil ekstraksi dan isolasi positif mengandung senyawa aktif acetogenin dan dari hasil analisis kualitatif diketahui F005 mengandung acetogenin paling banyak dibandingkan dengan hasil isolasi. Besarnya kandungan acetogenin pada F005 adalah 14.2% sedangkan untuk hasil isolasi berkisar antara 7% - 12%.

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Bioactive substance annonaceous acetogenin which is originated/derived from soursop plant (Annona muricata) has been found to posses specific cytotoxic and anti-tumor properties to several cancers including colon, pancreatic, lung, and breast cancers. The acatogenin extracted from sousop leaves was analyzed qualitatively using TLC, BST, FTIR and quantititavely using UV-Vis spectrophotometry. The extracts were divided into 5 (five) fractions and F005 fraction was found to contain acetogenin. The F005 was isolated, producing 13 bottles in which bottles 6 to 9 contained acetogenin.

Quantitaive analysis was performed by measuring acetogenin lactone group using standard andrographolida compound. The use of this standard compound was due to the difficulty in finding pure acetogenin compound, and by the fact that andrographolida compound have similar lactone group with that of acetogenin, In addition, in soursop leaves there was only acetogenin which had lactone group so that the determination based on lacton group could be carried out.

On the basis of qualitative analysis, the result of extraction and isolation were positively confirmed to contain the active acetogenin ingredient, while the quantitative analysis showed that F005 produced more acetogenin than the isolation."

"Keladi tikus (Typhonium flagelliforme (Lodd) Blume merupakan herba yang secara tradisional digunakan sebagai antikanker. Tujuan penelitian adalah mengetahui kandungan senyawa kimia ekstrak metanol dari daun T. Flagelliforme. Isolasi senyawa dilakukan dengan cara maserasi, dilanjutkan dengan pemisahan sesuai dengan kepolarannya dan diuji aktivitas antioksidan, aktivitas antimikroba dan uji bioaktivitas terhadap larva A.salina Leach. Fasa aktif sebagai antioksidan, antimikroba dan toksisitas terhadap A.salina ditunjukkan oleh fasa etil asetat dengan nilai IC50 56,32 μg/mL, diameter hambatan 16,2 mm (Pseudomonas aeruginosa) dan 18,1 mm (Bacillus subtilis) dan LC50 54,82 μg/mL. Uji sitotoksisitas terhadap sel kanker T-47D dan sel murine leukemia P388 juga dilakukan terhadap fasa aktif tersebut. Pemisahan lanjutan dari fasa aktif dilakukan melalui kromatografi cair vakum (SiO2, diklormetana, isopropanol~ metanol) secara gradien dan kromatografi kolom (LH20, metanol). Pemurnian secara kromatografi cair kinerja tinggi preparatif kolom C18 dengan eluen metanol-air secara gradien. Penentuan struktur molekul dengan menganalisis data spektrum UV-Vis, FTIR, LC-MS MS, 1H-NMR, 13C-NMR, dan 2D-NMR. Hasil isolasi terhadap fasa etil asetat T. flagelliforme (Lodd) Blume diperoleh 3 senyawa yaitu adenin, adenosin dan 6-C-glukopiranosilapigenin. Ketiga senyawa tidak aktif terhadap sel kanker T-47D namun menunjukkan aktivitas terhadap sel murine leukemia P-388 masing-masing dengan nilai IC50 71,36; 87,26 dan 34,41 μg/mL, sedangkan senyawa 6-C-glukopiranosilapigenin memiliki aktivitas antioksidan dengan nilai IC50 34,39 ug/mL serta toksisitas terhadap larva A.salina dengan nilai LC50 15,84 μg/mL. Semua nilai aktivitas tersebut masih lebih kecil dibandingkan kontrol masing-masing.

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Keladi tikus (T. flagelliforme (Lodd)Blume ), is a medicinal herb which traditionally used as anticancer. The aim of study was to determine chemical compounds of the methanol extract. The isolation of compound was carried out by maceration, followed by separation according to polarity. The ethyl acetate as active phase showed the antioxidant activity with IC50 value of 56.32 μg/mL, the antimicrobial activity with inhibiton zone 16.2 mm (Pseudomonas aeruginosa) and 18.1 mm (Bacillus subtilis), and bioactivity against A.salina Leach larvae with LC50 value of 54.82 μg/mL. The cytotoxicity against T-47D cancer cells and P.388 leukemia cells also was carried out to the active phase. The separation and purification were conducted by VLC (SiO2, dichloromethane-isopropanol, ~ methanol) using gradient elution and column chromatography (LH20, methanol) and HPLC preparative with C18 column methanol-water as eluent. Molecule structure determination was analyzed using the UV-Vis spectral data, FTIR, LC-MS MS, 1D NMR, 2D NMR. The result from the active phase obtained three compounds namely adenine, adenosine and 6-C-glucopyranosylapigenin. All three compounds were not active against T-47D cancer cells but they showed activity against P-388 leukemia cells with IC50 values of 71.36; 87.26 and 34.41 μg/mL respectively, while 6-Cglucopyranosylapigenin compound showed antioxidant activity with IC50 value of 34.39 μg/mL and toxicity against A.salina with LC50 value of 15.84 μg/mL. All the values of activity however are still lower compare to the relevant compound as control."