A new method for the inversion of atmospheric parameters of A/Am stars

We present an automated procedure that derives simultaneously the effective temperature $T_{eff}$, the surface gravity logg, the metallicity [Fe/H], and the equatorial projected rotational velocity vsini for "normal" A and Am stars. The procedure is based on the principal component analysis inversion method of Paletou et al. (2015a). A sample of 322 high resolution spectra of F0-B9 stars, retrieved from the Polarbase, SOPHIE, and ELODIE databases, were used to test this technique with real data. We have selected the spectral region from 4400-5000\AA\ as it contains many metallic lines and the Balmer H$\beta$ line. Using 3 datasets at resolving powers of R=42000, 65000 and 76000, about 6.6x$10^6$ synthetic spectra were calculated to build a large learning database. The Online Power Iteration algorithm was applied to these learning datasets to estimate the principal components (PC). The projection of spectra onto the few PCs offered an efficient comparison metric in a low dimensional space. The spectra of the well known A0- and A1-type stars, Vega and Sirius A, were used as control spectra in the three databases. Spectra of other well known A-type stars were also employed in order to characterize the accuracy of the inversion technique. All observational spectra were inverted and atmospheric parameters derived. After removal of a few outliers, the PCA-inversion method appears to be very efficient in determining $T_{eff}$, [Fe/H], and vsini for A/Am stars. The derived parameters agree very well with previous determinations. Using a statistical approach, deviations of around 150 K, 0.35 dex, 0.15 dex, and 2 km/s were found for $T_{eff}$, logg, [Fe/H], and vsini with respect to literature values for A-type stars. The PCA-inversion proves to be a very fast, practical, and reliable tool for estimating stellar parameters of FGK and A stars, and deriving effective temperatures of M stars.Comment: 16 pages, 9 figures. Accepted in A&

A content, pedagogy and technology [CPT] approach to TPACK

TPACK is a framework for the learning process in which educators combine Technological, Pedagogical and Content Knowledge to deliver the learning experience. Therefore, TPACK can be defined as a complex interaction between the technology, pedagogy and content. TPACK expresses the overlap between these factors in a two-dimensional space, placing TPACK at the centre. Educators can place their teaching episode within this space and ask, if I place my delivery at this point is it the best point in the TPACK space? Secondly educators may ask how can the best point within the space be determined? The CPT model proposes an attempt to address these questions by recasting TPACK as a three-dimensional pseudo-vector space allowing expected outcomes and observed outcomes to be analysed. For the study presented here our null hypothesis is: H0 = there is no significant difference between the observed and expected outcomes

Developing a predictive model for the enhanced learning outcomes by the use of technology

This paper reports on the initial outcomes of a study to develop a model to identify the relationship between technological facilities such as iPad, MacBook, Apps and software etc., pedagogy (that can be defined as any conscious activity by one person designed to enhance learning in another (Watkins and Mortimore, 1999 [1])), curriculum and learning. The new model can be called CPT Model. This is a new area of study. The model will test the difference between the observed learning outcomes and the learning outcomes predicted. This model can predict the outcomes for assessing the students’ progress. Using a three-dimensional vector space in the form of 3D equations, after the integration between the ICT and the education, students’ observed and predicted progress (that was calculated using the CPT model) were compared. These rates were very close to each other. Therefore the null hypothesis, "there is not a significant difference between the observed (actual) and expected outcomes"

Severe B Cell Deficiency in Mice Lacking the Tec Kinase Family Members Tec and Btk

The cytoplasmic protein tyrosine kinase Tec has been proposed to have important functions in hematopoiesis and lymphocyte signal transduction. Here we show that Tec-deficient mice developed normally and had no major phenotypic alterations of the immune system. To reveal potential compensatory roles of other Tec kinases such as Bruton's tyrosine kinase (Btk), Tec/Btk double-deficient mice were generated. These mice exhibited a block at the B220+CD43+ stage of B cell development and displayed a severe reduction of peripheral B cell numbers, particularly immunoglobulin (Ig)MloIgDhi B cells. Although Tec/Btknull mice were able to form germinal centers, the response to T cell–dependent antigens was impaired. Thus, Tec and Btk together have an important role both during B cell development and in the generation and/or function of the peripheral B cell pool. The ability of Tec to compensate for Btk may also explain phenotypic differences in X-linked immunodeficiency (xid) mice compared with human X-linked agammaglobulinemia (XLA) patients

Faktor-faktor Yang Mempengaruhi Struktur Modal Pada Perusahaan Bumn Di Indonesia

Kebijakan mengenai struktur modal berperan penting dalam kegiatan operasional dan kemajuan Perusahaan. Perlu dilakukan analisis untuk membuat keputusan yang efektif mengenai struktur modal optimal Perusahaan. Tujuan penelitian ini untuk mengetahui apakah faktor-faktor seperti tarif pajak, ukuran Perusahaan, likuiditas, fleksibilitas keuangan, pemanfaatan aset, tingkat pertumbuhan, risiko, profitabilitas, pemanfaatan aset, dan kepemilikan pemerintah berpengaruh terhadap struktur modal. Dalam penelitian ini populasi dan sampel berasal dari Perusahaan BUMN yang terdaftar di BEI tahun 2009-2014. Penarikan sampel dengan teknik purposive sampling sehingga diperoleh 90 sampel. Pengujian dalam penelitian dilakukan dengan uji data panel. Hasil penelitian ini adalah ukuran Perusahaan, likuiditas, fleksibilitas keuangan, struktur aktiva, pertumbuhan, profitabilitas dan kepemilikan pemerintah memiliki pengaruh signifikaan terhadap struktur modal. Pajak, kinerja saham, risiko, dan pemanfaatan aset tidak memiliki pengaruh signifikan terhadap struktur modal. Penelitian memiliki implikasi bagi manajemen untuk mempertahankan tingkat likuiditas, mempertahankan cadangan modal, dan meningkatkan kinerja. Bagi investor dapat mempertimbangkan pertumbuhan Perusahaan jika ingin membeli saham Perusahaan

Preferensi Kecoak Amerika Periplaneta Americana (L.) (Blattaria : Blattidae) terhadap Baiting Gel

Cockroach Periplaneta americana is a type of species cockroach that is most abundant in an urban environment in Indonesia. Cockroaches can be a mechanical vector of various pathogens such as fungi, viruses, bacteria and protozoa. Baiting gel is one way of controlling cockroaches. Each baiting gel has a different efficacy of the species and location. This study aimed to analyze the differences in preferences Periplaneta americana against baiting commercial gel with active ingredient imidacloprid (BTX) and fipronil (MFF). Research conducted at the Laboratory of Entomology FKM Diponegoro University. The study design used is a true experiment with repeating the experiment 3 times. Data were analyzed using independent t-test (α = 0.05). Result of observation showed that in the nymph stage Periplaneta americana preference no significant difference to the baiting gel BTX and MFF with p value 0.710. So also, on the stage of imago Periplaneta americana preference no significant difference to the baiting gel BTX and MFF with p value 0,849