Detailed Studies of Pixelated CZT Detectors Grown with the Modified Horizontal Bridgman Method

The detector material Cadmium Zinc Telluride (CZT), known for its high resolution over a broad energy range, is produced mainly by two methods: the Modified High-Pressure Bridgman (MHB) and the High-Pressure Bridgman (HPB) process. This study is based on MHB CZT substrates from the company Orbotech Medical Solutions Ltd. with a detector size of 2.0x2.0x0.5 cm^3, 8x8 pixels and a pitch of 2.46 mm. Former studies have emphasized only on the cathode material showing that high-work-function improve the energy resolution at lower energies. Therfore, we studied the influence of the anode material while keeping the cathode material constant. We used four different materials: Indium, Titanium, Chromium and Gold with work-functions between 4.1 eV and 5.1 eV. The low work-function materials Indium and Titanium achieved the best performance with energy resolutions: 2.0 keV (at 59 keV) and 1.9 keV (at 122 keV) for Titanium; 2.1 keV (at 59 keV) and 2.9 keV (at 122 keV) for Indium. These detectors are very competitive compared with the more expensive ones based on HPB material if one takes the large pixel pitch of 2.46 mm into account. We present a detailed comparison of our detector response with 3-D simulations, from which we determined the mobility-lifetime-products for electrons and holes. Finally, we evaluated the temperature dependency of the detector performance and mobility-lifetime-products, which is important for many applications. With decreasing temperature down to -30C the breakdown voltage increases and the electron mobility-lifetime-product decreases by about 30% over a range from 20C to -30C. This causes the energy resolution to deteriorate, but the concomitantly increasing breakdown voltage makes it possible to increase the applied bias voltage and restore the full performance.Comment: Accepted for publication in Astroparticle Physics, 25 pages, 13 figure

Peranan Organisasi Rohani Islam dalam Meningkatkan Nilai Religius dan Kejujuran Siswa

The purpose of this research was to describe various activities of Islamic spiritual organization (Rohis) that play a role in increasing the value of religious and rectitude students. The research methodology used in this research descriptive qualitative with the informants were vice headmaster of student field, the trustees of Islamic spiritual organization, former trustees of Islamic spiritual organization and member of Islamic spiritual organization. Technique of data collection used was interview guidelines, observation guidelines, documentation guidelines and likert scale. Technique data analysis was using analysis of interactive model. Based on the result of the research which has been done, it is known that Islamic spiritual activities in proselytizing common (study Islamic basic, guidance in reading Al-Quran, tadabur of nature, wall magazine), have a role in increasing the value of religious while the activities in special proselytizing (mentoring) have a role in increasing value of rectitude students in Senior High School 1 Pesisir Barat.Tujuan penelitian ini adalah mendekripsikan peranan kegiatan organisasi Rohani Islam (Rohis) yang berperan dalam meningkatkan nilai religius dan kejujuran siswa. Metode penelitian yang digunakan dalam penelitian ini deskriptif kualitatif dengan informan wakil kepala sekolah bidang kesiswaan, pembina Rohani Islam, mantan pembina Rohani Islam, dan anggota Rohis. Teknik pengumpulan data menggunakan pedoman wawancara, pedoman observasi, pedoman dokumentasi dan skala likert. Teknik analisis data menggunakan Analysis Interactive Model. Berdasarkan hasil penelitian yang telah dilakukan dapat diketahui bahwa kegiatan Rohani Islam dalam dakwah umum (studi dasar Islam, bimbingan baca Al-Quran, tadabur alam, majalah dinding) berperan dalam meningkatkan nilai religius sedangkan kegiatan dalam dakwah khusus (mentoring) berperan dalam meningkatakan nilai kejujuran siswa di SMA Negeri 1 Pesisir Barat

HATS-1b: The First Transiting Planet Discovered by the HATSouth Survey

We report the discovery of HATS-1b, a transiting extrasolar planet orbiting the moderately bright V=12.05 G dwarf star GSC 6652-00186, and the first planet discovered by HATSouth, a global network of autonomous wide-field telescopes. HATS-1b has a period P~3.4465 d, mass Mp~1.86MJ, and radius Rp~1.30RJ. The host star has a mass of 0.99Msun, and radius of 1.04Rsun. The discovery light curve of HATS-1b has near continuous coverage over several multi-day periods, demonstrating the power of using a global network of telescopes to discover transiting planets.Comment: Submitted to AJ 10 pages, 5 figures, 6 table

Methylation landscape in the genome of higher plants of agronomical interest

In eukaryotic cells the methylation of cytosines in DNA is an essential mechanism which is implied in the dynamic organization of the genome structure, in relation to genes expression. Plant genomes contain a significant proportion and variable according to the species, of sequences which are likely to be methylated during the life of the plant. It is known that the establishment and the maintenance of methylation profiles in both genomic areas and specific sequences constitute a crucial mediator in the modulation of genes expression during development. Recent studies have evidenced the implication of epimutations in the adaptation of plants to their environment particularly in response to biotic and abiotic stresses. Recently, the complete mapping of methylation in the genomes of Arabidopsis thaliana and rice provided invaluable information on the distribution of methylation within genes in relation to their expression. The impact of changes in the methylation profiles on the characters of agronomic importance has not been intensively studied yet, whereas this question takes a considerable importance in the context of an increasing food demand and foreseen global climate changes. The METHYLANDSCAPE project proposes to isolate genomic DNA sequences on the basis of their degree of methylation and to connect the variation of their methylation profiles with, on the one hand, the expression of the corresponding genes and, on the other hand, with environmental or developmental processes. Thus, it should be possible to identify genes which expression is differentially controlled by methylation during development and/or in situation of stress, and likely to have an influence on the agronomic value of the plant. The METHYLANDSCAPE partners thus propose to bring signification advances in plant genomics on four original species, by integrating DNA methylation mapping and the relationship between epigenome and transcriptome, up to the generation of methylation-sensitive markers linked with characters of agronomic importance. (Texte intégral

Analisis Bioinformatika Berbasis WEB untuk Eksplorasi Enzim Kitosanase Berdasarkan Kemiripan Sekuens

Eksplorasi enzim secara tradisional dengan kultivasi mikroba sekarang ini tidak lagi efisien, karena menghabiskan waktu dan biaya. Bioinformatik berbasis web hadir untuk melakukan serangkaian analisis sekuen, baik itu DNA maupun protein, yang dapat digunakan sebagai penelitian pendahuluan, sehingga ekplorasi enzim menjadi lebih tepat sasaran. Penelitian ini telah melakukan analisis potongan sekuen 16S ribosomal RNA yang didapat dari 6 bakteri yang berasosiasi dengan udang. Analisis yang dilakukan adalah untuk mencari tahu tersedianya sekuen tersebut telah ada di Gene Bank atau merupakan strain baru khas Indonesia yang belum terpublikasi. Dengan menggunakan database 16S Microbial dan Reference Genomic Sequence, serta fasilitas BLAST nucleotide dan CLUSTALW2 didapatkan 5 nama bakteri yaitu Micromonospora sp. L5, Aeromonas veronii B565, Staphylococcus epidermidis ATCC 12228, Burkholderia sp. JV3, dan Acinetobacter baumanniiAB307-0294. Kelima mikroba ini memiliki tidak mempunyai gen kitosanase tetapi penyandi kitinase. Ketidakhadiran gen kitosanase dalam genome mikroba menjadikan mikroba unik untuk diketahui sekuens gen kitosanasenya, yang juga berpeluang untuk dipublikasikan

Fully Frustrated Ising System on a 3D Simple Cubic Lattice: Revisited

Using extensive Monte Carlo simulations, we clarify the critical behaviour of the 3 dimensional simple cubic Ising Fully Frustrated system. We find two transition temperatures and two long range ordered phases. Within the present numerical accuracy, the transition at higher temperature is found to be second order and we have extracted the standard critical exponent using finite size scaling method. On the other hand, the transition at lower temperature is found to be first order. It is argued that entropy plays a major role on determining the low temperature state.Comment: 14 pages 14 figures iop style include

Stepwise Lateral Extension of Phenyl-Substituted Linear Polyphenylenes

Polyphenylenes (PPs) are unique polymers showing high mechanical strength and chemical stability, and having potential applications, for example, in proton transfer and gas‐separation membranes. Moreover, phenyl‐substituted linear PPs can serve as precursors for bottom‐up syntheses of graphene nanoribbons (GNRs), a new class of nanoscale carbon materials that appear promising for nanoelectronics. Notably, lateral extensions of linear PPs with appropriate “branched” phenyl substituents, that is, avoiding spatial overlap of benzene rings in their projections into a plane, can lead to wider GNRs with modulated electronic and optical properties. GNRs with widths up to ≈2 nm are obtained, but synthetic methods to further expand PPs laterally so as to achieve even wider GNRs have not yet been developed. Here, phenyl‐substituted linear PPs bearing two ethynyl groups at “outer” positions in each repeating unit, together with 3,4‐diphenylcyclopentadienones bearing a trimethylsilyl‐protected ethynyl group are used for stepwise lateral extension of the PPs, based on a sequence of Diels–Alder cycloadditions and deprotections. Each successive reaction step is corroborated by 1H NMR and IR spectroscopy, as well as gel permeation chromatography, providing a new pathway toward branched polyphenylenes with linear‐PP‐backbones that can potentially serve as precursors of wider GNRs with tunable electronic bandgaps

Ground-based detection of sodium in the transmission spectrum of exoplanet HD209458b

[Context] The first detection of an atmosphere around an extrasolar planet was presented by Charbonneau and collaborators in 2002. In the optical transmission spectrum of the transiting exoplanet HD209458b, an absorption signal from sodium was measured at a level of 0.023+-0.006%, using the STIS spectrograph on the Hubble Space Telescope. Despite several attempts, so far only upper limits to the Na D absorption have been obtained using telescopes from the ground, and the HST result has yet to be confirmed. [Aims] The aims of this paper are to re-analyse data taken with the High Dispersion Spectrograph on the Subaru telescope, to correct for systematic effects dominating the data quality, and to improve on previous results presented in the literature. [Methods] The data reduction process was altered in several places, most importantly allowing for small shifts in the wavelength solution. The relative depth of all lines in the spectra, including the two sodium D lines, are found to correlate strongly with the continuum count level in the spectra. These variations are attributed to non-linearity effects in the CCDs. After removal of this empirical relation the uncertainties in the line depths are only a fraction above that expected from photon statistics. [Results] The sodium absorption due to the planet's atmosphere is detected at >5 sigma, at a level of 0.056+-0.007% (2x3.0 Ang band), 0.070+-0.011% (2x1.5 Ang band), and 0.135+-0.017% (2x0.75 Ang band). There is no evidence that the planetary absorption signal is shifted with respect to the stellar absorption, as recently claimed for HD189733b. The measurements in the two most narrow bands indicate that some signal is being resolved.[abridged]Comment: Latex, 7 pages: accepted for publication in Astronomy & Astrophysic

The K2-ESPRINT Project VI: K2-105 b, a Hot-Neptune around a Metal-rich G-dwarf

We report on the confirmation that the candidate transits observed for the star EPIC 211525389 are due to a short-period Neptune-sized planet. The host star, located in K2 campaign field 5, is a metal-rich ([Fe/H] = 0.26$\pm$0.05) G-dwarf (T_eff = 5430$\pm$70 K and log g = 4.48$\pm$0.09), based on observations with the High Dispersion Spectrograph (HDS) on the Subaru 8.2m telescope. High-spatial resolution AO imaging with HiCIAO on the Subaru telescope excludes faint companions near the host star, and the false positive probability of this target is found to be <$10^{-6}$ using the open source vespa code. A joint analysis of transit light curves from K2 and additional ground-based multi-color transit photometry with MuSCAT on the Okayama 1.88m telescope gives the orbital period of P = 8.266902$\pm$0.000070 days and consistent transit depths of $R_p/R_\star \sim 0.035$ or $(R_p/R_\star)^2 \sim 0.0012$. The transit depth corresponds to a planetary radius of $R_p = 3.59_{-0.39}^{+0.44} R_{\oplus}$, indicating that EPIC 211525389 b is a short-period Neptune-sized planet. Radial velocities of the host star, obtained with the Subaru HDS, lead to a 3\sigma\ upper limit of 90 $M_{\oplus} (0.00027 M_{\odot})$ on the mass of EPIC 211525389 b, confirming its planetary nature. We expect this planet, newly named K2-105 b, to be the subject of future studies to characterize its mass, atmosphere, spin-orbit (mis)alignment, as well as investigate the possibility of additional planets in the system.Comment: 11 pages, 9 figures, 4 tables, PASJ accepte