Pembangunan Aplikasi Perhitungan Honor Dan Pengukuran Kinerja Asisten Praktikum Berbasis SaaS

Bagi suatu perguruan tinggi, kegiatan praktikum sangat penting untuk mendukung pembelajaran di kelas. Beberapa masalah yang muncul dalam pengelolaan kegiatan praktikum seperti keterlambatan pengumpulan berita acara praktikum (BAP) sehingga memperlambat perhitungan, pembayaran dan pelaporan honor asprak. Dibutuhkan waktu sekitar dua minggu untuk rekapitulasi dan validasi ratusan lembar BAP yang telah terkumpul setiap bulannya. Dibutuhkan pengolahan data lebih lanjut untuk menilai kinerja asprak berdasarkan data BAP. Untuk mengatasi permasalahan di atas maka dibangun aplikasi perhitungan honor dan kinerja asprak. Aplikasi ini digunakan untuk mengelola data BAP, perhitungan dan pelaporan honor, perhitungan nilai transkrip aktivitas kemahasiswaan (TAK) dan pencetakan sertifikat asprak. Keterbatasan SDM atau biaya menyebabkan tidak semua perguruan tinggi dapat langsung membuat aplikasi yang dibutuhkan. Oleh karena itu aplikasi ini dibangun berbasis Software as A Service (SaaS). Aplikasi ini dikembangkan dengan metode analisis perancangan terstruktur dengan model waterfall. Pengumpulan data kebutuhan aplikasi dilakukan dengan survey ke fakultas-fakultas di Universitas Telkom. Hasilnya dianalisis dan dikembangkan menjadi rancangan aplikasi. Aplikasi diimplementasikan pada pemrograman PHP. Pengujian dilakukan dengan metode black box testing. Hasilnya berupa aplikasi SaaS untuk perhitungan honor dan pengukuran kinerja asisten praktikum. Perguruan tinggi pengguna aplikasi SaaS ini dapat melakukan kostumisasi terhadap fitur yang ada sesuai dengan kebutuhan

Complement Activation Determines the Therapeutic Activity of Rituximab In Vivo

Rituximab is an anti-CD20 chimeric mAb effective for the treatment of B-NHL. It can lyse lymphoma cells in vitro through both C- and Ab-dependent cellular cytotoxicity. The mechanism of action of rituximab in vivo is however still unclear. We have set up a new in vivo model in nonimmunodeficient mice by stable transduction of the human CD20 cDNA in the murine lymphoma line EL4. Animals injected i.v. with the EL4-CD20+ lymphoma cells died within 30 days with evident liver, spleen, and bone marrow involvement, confirmed by immunohistochemistry and PCR analysis. A single injection of rituximab or the murine anti-CD20 Ab 1F5, given i.p. 1 day after the tumor, cured 100% of the animals. Indeed, at week 4 after tumor cell inoculation, CD20+ cells were undetectable in all organs analyzed in rituximab-treated animals, as determined by immunohistochemistry and PCR. Rituximab had no direct effect on tumor growth in vitro. Depletion of either NK cells or neutrophils or both in tumor-injected animals did not affect the therapeutic activity of the drug. Similarly, rituximab was able to eradicate tumor cells in athymic nude mice, suggesting that its activity is T cell independent. In contrast, the protective activity of rituximab or the 1F5 Ab was completely abolished in syngeneic knockout animals lacking C1q, the first component of the classical pathway of C (C1qa−/−). These data demonstrate that C activation is fundamental for rituximab therapeutic activity in vivo

Polarimetric Evidence of Non-Spherical Winds

Polarization observations yield otherwise unobtainable information about the geometrical structure of unresolved objects. In this talk we review the evidences for non-spherically symmetric structures around Luminous Hot Stars from polarimetry and what we can learn with this technique. Polarimetry has added a new dimension to the study of the envelopes of Luminous Blue Variables, Wolf-Rayet stars and B[e] stars, all of which are discussed in some detail.Comment: 8 pages, 2 encapsulated Postscript figures, uses lamuphys.sty. Invited review to appear in IAU Coll. 169, Variable and Non-Spherical Stellar Winds in Luminous Hot Stars, eds. B. Wolf, A.Fullerton and O. Stahl (Springer

Spitzer SAGE survey of the Large Magellanic Cloud II: Evolved Stars and Infrared Color Magnitude Diagrams

Color-magnitude diagrams (CMDs) are presented for the Spitzer SAGE (Surveying the Agents of a Galaxy's Evolution) survey of the Large Magellanic Cloud (LMC). IRAC and MIPS 24 um epoch one data are presented. These data represent the deepest, widest mid-infrared CMDs of their kind ever produced in the LMC. Combined with the 2MASS survey, the diagrams are used to delineate the evolved stellar populations in the Large Magellanic Cloud as well as Galactic foreground and extragalactic background populations. Some 32000 evolved stars brighter than the tip of the red giant branch are identified. Of these, approximately 17500 are classified as oxygen-rich, 7000 carbon-rich, and another 1200 as ``extreme'' asymptotic giant branch (AGB) stars. Brighter members of the latter group have been called ``obscured'' AGB stars in the literature owing to their dusty circumstellar envelopes. A large number (1200) of luminous oxygen--rich AGB stars/M supergiants are also identified. Finally, there is strong evidence from the 24 um MIPS channel that previously unexplored, lower luminosity oxygen-rich AGB stars contribute significantly to the mass loss budget of the LMC (1200 such sources are identified).Comment: LaTex, 31 pages, 10 figures. Accepted for publication in the Astronomical Journa

Spitzer Sage Survey of the Large Magellanic Cloud. III. Star Formation and ~1000 New Candidate Young Stellar Objects

We present ~1000 new candidate Young Stellar Objects (YSOs) in the Large Magellanic Cloud selected from Spitzer Space Telescope data, as part of the Surveying the Agents of a Galaxy's Evolution (SAGE) Legacy program. The YSOs, detected by their excess infrared (IR) emission, represent early stages of evolution, still surrounded by disks and/or infalling envelopes. Previously, fewer than 20 such YSOs were known. The candidate YSOs were selected from the SAGE Point Source Catalog from regions of color-magnitude space least confused with other IR-bright populations. The YSOs are biased toward intermediate- to high-mass and young evolutionary stages, because these overlap less with galaxies and evolved stars in color-magnitude space. The YSOs are highly correlated spatially with atomic and molecular gas, and are preferentially located in the shells and bubbles created by massive stars inside. They are more clustered than generic point sources, as expected if star formation occurs in filamentary clouds or shells. We applied a more stringent color-magnitude selection to produce a subset of "high-probability" YSO candidates. We fitted the spectral-energy distributions (SEDs) of this subset and derived physical properties for those that were well fitted. The total mass of these well-fitted YSOs is ~2900 M_☉ and the total luminosity is ~2.1 × 10^6 L_☉ . By extrapolating the mass function with a standard initial mass function and integrating, we calculate a current star-formation rate of ~0.06 M_☉ yr^(–1), which is at the low end of estimates based on total ultraviolet and IR flux from the galaxy (~0.05 – 0.25 M_☉ yr^(–1)), consistent with the expectation that our current YSO list is incomplete. Follow-up spectroscopy and further data mining will better separate the different IR-bright populations and likely increase the estimated number of YSOs. The full YSO list is available as electronic tables, and the SEDs are available as an electronic figure for further use by the scientific community

Eta Carinae and the Luminous Blue Variables

We evaluate the place of Eta Carinae amongst the class of luminous blue variables (LBVs) and show that the LBV phenomenon is not restricted to extremely luminous objects like Eta Car, but extends luminosities as low as log(L/Lsun) = 5.4 - corresponding to initial masses ~25 Msun, and final masses as low as ~10-15 Msun. We present a census of S Doradus variability, and discuss basic LBV properties, their mass-loss behaviour, and whether at maximum light they form pseudo-photospheres. We argue that those objects that exhibit giant Eta Car-type eruptions are most likely related to the more common type of S Doradus variability. Alternative atmospheric models as well as sub-photospheric models for the instability are presented, but the true nature of the LBV phenomenon remains as yet elusive. We end with a discussion on the evolutionary status of LBVs - highlighting recent indications that some LBVs may be in a direct pre-supernova state, in contradiction to the standard paradigm for massive star evolution.Comment: 27 pages, 6 figures, Review Chapter in "Eta Carinae and the supernova imposters" (eds R. Humphreys and K. Davidson) new version submitted to Springe

STEP: the VST survey of the SMC and the Magellanic Bridge - I : Overview and first results

STEP (the SMC in Time: Evolution of a Prototype interacting late-type dwarf galaxy) is a Guaranteed Time Observation survey being performed at the VST (the ESO VLT Survey Telescope). STEP will image an area of 74 sq. deg. covering the main body of the Small Magellanic Cloud (32 sq. deg.), the Bridge that connects it to the Large Magellanic Cloud (30 sq. deg.) and a small part of the Magellanic Stream (2 sq. deg.). Our g, r, i, Hα photometry is able to resolve individual stars down to magnitudes well below the main-sequence turn-off of the oldest populations. In this first paper, we describe the observing strategy, the photometric techniques and the upcoming data products of the survey. We also present preliminary results for the first two fields for which data acquisition is completed, including some detailed analysis of the two stellar clusters IC 1624 and NGC 419.Peer reviewedFinal Accepted Versio

The evolution of rotating stars

First, we review the main physical effects to be considered in the building of evolutionary models of rotating stars on the Upper Main-Sequence (MS). The internal rotation law evolves as a result of contraction and expansion, meridional circulation, diffusion processes and mass loss. In turn, differential rotation and mixing exert a feedback on circulation and diffusion, so that a consistent treatment is necessary. We review recent results on the evolution of internal rotation and the surface rotational velocities for stars on the Upper MS, for red giants, supergiants and W-R stars. A fast rotation is enhancing the mass loss by stellar winds and reciprocally high mass loss is removing a lot of angular momentum. The problem of the ``break-up'' or $\Omega$-limit is critically examined in connection with the origin of Be and LBV stars. The effects of rotation on the tracks in the HR diagram, the lifetimes, the isochrones, the blue to red supergiant ratios, the formation of W-R stars, the chemical abundances in massive stars as well as in red giants and AGB stars, are reviewed in relation to recent observations for stars in the Galaxy and Magellanic Clouds. The effects of rotation on the final stages and on the chemical yields are examined, as well as the constraints placed by the periods of pulsars. On the whole, this review points out that stellar evolution is not only a function of mass M and metallicity Z, but of angular velocity $\Omega$ as well.Comment: 78 pages, 7 figures, review for Annual Review of Astronomy and Astrophysics, vol. 38 (2000