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"Ivermectin merupakan obat antihelmintik berspektrum luas yang digunakan untuk mengendalikan penyakit onchocerciasis dari parasit nematoda. Sebagai obat cacing, ivermectin didisain untuk memiliki kadar yang tinggi di saluran cerna, sehingga yang masuk sistemik tergolong rendah. Oleh karena kadar ivermectin yang sangat kecil, dibutuhkan metode yang sensitif dan selektif untuk analisis ivermectin dalam darah. Beberapa metode telah dikembangkan menggunakan plasma dan Dried Blood Spot, namun masih terdapat kekurangan karena terdapat efek hematokrit. Oleh karena itu, penelitian ini bertujuan untuk mengembangkan metode analisis ivermectin yang tervalidasi dengan baku dalam doramectin menggunakan Kromatografi Cair Kinerja Ultra Tinggi – tandem Spektrometri Massa (KCKUT-SM/SM). Deteksi menggunakan spektrometri massa triple quadrupole dengan mode electrospray ionization (ESI) positif. Matriks biologis yang digunakan yaitu darah utuh dalam Volumetric Absorptive Microsampling (VAMS), kemudian dipreparasi menggunakan metode pengendapan protein dengan campuran asetonitril dan metanol (1:1). VAMS dipilih karena tidak terdapat efek hematokrit, dibutuhkan volume sampel yang sedikit dan akurat, serta pengambilannya lebih efisien. Kondisi analisis optimum diperoleh menggunakan kolom Acquity® UPLC BEH C18 (2,1 x 100 mm; 1,7 m); fase gerak amonium format 5 mM pH 3 dan asetonitril (10:90); laju alir 0,2 mL/menit; mode elusi isokratik selama 5 menit dengan suhu kolom 50˚C; deteksi menggunakan Multiple Reaction Monitoring (MRM) pada nilai m/z 892,41 > 569,5 untuk ivermectin dan 916,41 > 331,35 untuk doramectin. Metode analisis telah tervalidasi seluruhnya mengikuti pedoman dari US Food and Drug Administration tahun 2018. Nilai LLOQ 1 ng/mL dengan rentang konsentrasi linear pada 1 - 150 ng/mL

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Ivermectin is a broad-spectrum anthelmintic used to control onchocerciasis from nematode parasites. As an anthelmintic, ivermectin is designed to have high levels in the gastrointestinal tract, so that the systemic intake is relatively low. Due to the very small concentration of ivermectin, a sensitive and selective method is needed for the analysis of ivermectin in blood. Several methods have been developed using plasma and Dried Blood Spots, but there are still shortcomings due to hematocrit effects. Therefore, this study was conducted to develop a validated ivermectin analysis method with doramectin as the internal standard in using Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry. The analysis was performed using a triple quadrupole mass spectrometry with positive electrospray ionization (ESI) mode. The biological matrix used whole blood in Volumetric Absorptive Microsampling (VAMS) and extracted using the protein precipitation method with mixture of acetonitrile and methanol (1:1). VAMS has some advantages such as not affected by hematocrit, requires small and fixed volume of sample, also more efficient sampling process. The optimum conditions were obtained using the Acquity® UPLC BEH C18 column (2.1 x 100 mm; 1,7 m); flow rate was 0,2 mL/min; mobile phase was ammonium formate 5 mM pH 3 and acetonitrile (10:90); isocratic elusion for 5 minutes; Multiple Reaction Monitoring (MRM) detection with m/z values were 892.41 > 569.5 for ivermectin and 916,41 > 331,35 for doramectin. The method has been fully validated following the guidelines from US FDA (2018). LLOQ value was 1 ng/mL with a linear concentration range of 1 – 150 ng/mL."

"This greatly expanded third edition of Survival analysis : a self-learning text provides a highly readable description of state-of-the-art methods of analysis of survival/event-history data. The third edition continues to use the unique "lecture-book" format of the first two editions with one new chapter, additional sections and clarifications to several chapters, and a revised computer appendix. The Computer Appendix, with step-by-step instructions for using the computer packages STATA, SAS, and SPSS, is expanded this third edition to include the software package R."

"The spectral intensity of direct and scattered solar radiation is of fundamental importance for various studies in civil engineering, agriculture, solar power generation, and radiation budgetestimation. In this paper, we describe a ground-based, wide-spectral-range sensor that can be used for measuring spectral intensities both in the visible and near-infrared spectral regions.The measurements are conducted either with artificial light sources ordirect/scattered solar radiation. The measured spectra yields information on the absorption features of atmosphericgases such as nitrogen dioxide (NO2), carbon dioxide (CO2) and water vapor, as well as aerosol optical properties in the atmosphere. Relatively weak absorption of nitrogen dioxide is measured with the technique of differential optical absorption spectroscopy (DOAS), whereas aerosol, carbon dioxide, and water vapor amounts are measured by matching the observed spectra with simulated ones. Both High Resolution Transmission (HITRAN) and ModerateResolution Atmospheric Transmission (MODTRAN) database/codes are used to derive column amounts of absorbing molecular species and tocharacterize aerosol optical properties. "