932 research outputs found
Finite generation in -algebras and Hilbert -modules
We characterize -algebras and -modules such that every maximal
right ideal (resp. right submodule) is algebraically finitely generated. In
particular, -algebras satisfy the Dales--\.Zelazko conjecture.Comment: to appear in Studia Mathematic
Prague's Emission Fourier Transform Microwave Spectrometer - Design and Preliminary Results
The design, performance and operation of the high resolution microwave spectrometer are described. The spectrometer is based on the Fabry-Perot resonator supplemented by a pulsed supersonic nozzle for adiabatic cooling of the sample. The spectrometer’s high sensitivity and resolution are demonstrated by several examples
Invariant means on Abelian groups capture complementability of Banach spaces in their second duals
Let be a Banach space. Then is complemented in the bidual if
and only if there exists an invariant mean with
respect to a free Abelian group of rank equal to the cardinality of
, and this happens if and only if there exists an invariant mean with
respect to the additive group of . This improves upon previous results
due to Bustos Domecq =and the second-named author, where certain idempotent
semigroups of cardinality equal to the cardinality of were considered,
and answers a question of J.M.F. Castillo (private communication). En route to
the proof of the main result, we endow the family of all finite-dimensional
subspaces of an infinite-dimensional vector space with a structure of a free
commutative monoid with the property that the product of two subspaces contains
the respective subspaces, which is possibly of interest in itself.Comment: 12 pp., accepted for publication in Studia Mathematic
Analisis Tata Niaga Pupuk Bersubsidi di Kabupaten Purbalingga
Penelitian ini bertujuan untuk mengetahui proses tata niaga pupuk bersubsidi dari distributor sampai ke petani di Kabupaten Purbalingga, besarnya margin tata niaga yang diterima oleh masing-masing penyalur pupuk bersubsidi, mengetahui tingkat efisiensi tataniaga pupuk di Kabupaten Purbalingga. Metode yang digunakan dalam penelitian ini adalah metode studi kasus. Penelitian dilakukan di Kecamatan Kutasari dan Kecamatan Purbalingga Kabupaten Purbalingga. Pemilihan lokasi di lakukan secara Purposive sampling. Pada kelompok distributor, diambil dua distributor sebagai sampel dengan menggunakan metode proportionate stratified random sampling, untuk kelompok penyalur resmi diambil 13 sampel dengan metode proportionate stratified random sampling, diambil 20 kelompok tani sebagai sampel dengan metode snawball sampling dan 20 petani sebagai sampel padi monokultur dengan metode purposive sampling yang sudah memenuhi kriteria yang sudah ditentukan. Penelitian dilakukan selama delapan bulan, yaitu mulai bulan Desember 2015 sampai Mei 2016.Hasil penelitian menunjukan bahwa hanya ada satu pola saluran tata niaga pupuk bersubsidi yaitu dari distributor ke penyalur resmi kemudian ke kelompok tani selanjutnya dijual kepada konsumen akhir yaitu petani. Margin tata niaga pupuk bersubsidi tertinggipada pupuk urea, pupuk phonska dan pupuk ZA sebesar Rp.109,-/kg. Tingkat efisiensi tertinggi terdapat pada distributor pupuk organik sebesar 2,7
First principles based atomistic modeling of phase stability in PMN-xPT
We have performed molecular dynamics simulations using a shell model
potential developed by fitting first principles results to describe the
behavior of the relaxor-ferroelectric (1-x)PbMg1/3Nb2/3O3-xPbTiO3 (PMN-xPT) as
function of concentration and temperature, using site occupancies within the
random site model. In our simulations, PMN is cubic at all temperatures and
behaves as a polar glass. As a small amount of Ti is added, a weak polar state
develops, but structural disorder dominates, and the symmetry is rhombohedral.
As more Ti is added the ground state is clearly polar and the system is
ferroelectric, but with easy rotation of the polarization direction. In the
high Ti content region, the solid solution adopts ferroelectric behavior
similar to PT, with tetragonal symmetry. The ground state sequence with
increasing Ti content is R-MB-O-MC-T. The high temperature phase is cubic at
all compositions. Our simulations give the slope of the morphotropic phase
boundaries, crucial for high temperature applications. We find that the phase
diagram PMN-xPT can be understood within the random site model.Comment: 27 pages, 9 figure
Role of chromodomain helicase DNA-binding protein 2 in DNA damage response signaling and tumorigenesis.
The chromodomain helicase DNA-binding proteins (CHDs) are known to affect transcription through their ability to remodel chromatin and modulate histone deacetylation. In an effort to understand the functional role of the CHD2 in mammals, we have generated a Chd2 mutant mouse model. Remarkably, the Chd2 protein appears to play a critical role in the development, hematopoiesis and tumor suppression. The Chd2 heterozygous mutant mice exhibit increased extramedullary hematopoiesis and susceptibility to lymphomas. At the cellular level, Chd2 mutants are defective in hematopoietic stem cell differentiation, accumulate higher levels of the chromatin-associated DNA damage response mediator, cH2AX, and exhibit an aberrant DNA damage response after X-ray irradiation. Our data suggest a direct role for the chromatin remodeling protein in DNA damage signaling and genome stability maintenance
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The Application of Photoconductive Detectors to the Measurement of X-Ray Production in Laser Produced Plasmas
Photoconductive detectors (PCDs) offer an attractive alternative for the measurement of pulsed x-rays from laser produced plasmas. These devices are fast (FWHM approx.100 ps), sensitive and simple to use. We have used InP, GaAs, and Type IIa diamond as PCDs to measure x-rays emission from 100 eV to 100 keV. Specifically, we have used these detectors to measure total radiation yields, corona temperatures, and hot electron generated x-rays from laser produced plasmas. 5 refs., 4 figs
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