Numerical study of the ordering of the +-J XY spin-glass ladder

The properties of the domain-wall energy and of the correlation length are studied numerically for the one-dimensional +-J XY spin glass on the two-leg ladder lattice, focusing on both the spin and the chirality degrees of freedom. Analytic results obtained by Ney-Niftle et al for the same model were confirmed for asymptotically large lattices, while the approach to the asymptotic limit is slow and sometimes even non-monotonic. Attention is called to the occurrence of the SO(2)-Z_2 decoupling and its masking in spin correlations, the latter reflecting the inequality between the SO(2) and Z_2 exponents. Discussion is given concerning the behaviors of the higher-dimensional models.Comment: 14 pages, 10 figure

Design and Development of the Space Shuttle Tail Service Masts

The successful launch of a space shuttle vehicle depends on the proper operation of two tail service masts (TSMs). Reliable TSM operation is assured through a comprehensive design, development, and testing program. The results of the concept verification test (CVT) and the resulting impact on prototype TSM design are presented. The design criteria are outlined, and the proposed prototype TSM tests are described

Boron-oxygen defect in Czochralski-silicon co-doped with gallium and boron

We study the boron-oxygen defect in Si co-doped with gallium and boron with the hole density 10 times higher than the boron concentration. Instead of the linear dependence of the defect density on the hole density observed in boron and phosphorus compensated silicon, we find a proportionality to the boron concentration. This indicates the participation of substitutional, rather than interstitial,boron in the defect complex. The measured defectformationrate constant is proportional to the hole density squared, which gives credit to latent defect models against defectreactions limited by the diffusion and trapping of oxygen dimers by boron atoms

Pengembangan Mobile-Learning SARITHA-Apps Untuk Meningkatkan Hasil Belajar Dan Berpikir Kritis Mahasiswa S1 Pendidikan Biologi Universitas Palangka Raya

This research aims to develop mobile-learning SARITHA-Apps, describe product validity, analyze the development of mobile-learning SARITHA-Apps towards improving learning outcomes and critical thinking of undergraduate students in the Biology Education Study Program, FKIP Palangka Raya University. This research refers to the ADDIE development design and data collection using questionnaire sheets, media expert assessment sheets and material expert assessment sheets. The research results show: (1) one product has been produced as a result of the development of Mobile-Learning Environmental Science material, namely the SARITHA-Apps Mobile-Learning Application; (2) The average result of the Expert Team's assessment of the suitability of the SARITHA-Apps Mobile-Learning Application instrument and product is 91%, which means it is in the "Very Feasible" qualification; (2) The SARITHA-Apps Mobile-Learning application is able to improve student learning outcomes for environmental science material, namely with an N-Gain of 0.4, which means it is in the "Medium" category; (3) Student learning outcomes according to critical thinking skills from the questions given, it was found that the explanation indicator had the highest percentage increase value, namely 6% compared to the percentage increase in other critical thinking indicators, where the self-regulation indicator was 5%, while the analysis and analysis indicators inference of 2%.Penelitian ini bertujuan untuk mengembangkan mobile-learning SARITHA-Apps, mendeskripsikan validitas produk, menganalisis pengembangan mobile-learning SARITHA-Apps terhadap peningkatan hasil belajar dan berpikir kritis mahasiswa S1 di Program Studi Pendidikan Biologi, FKIP Universitas Palangka Raya. Penelitian ini mengacu pada desain pengembangan ADDIE dan pengumpulan data menggunakan lembar kuesioner, lembar penilain ahli media dan lembar penilaian ahli materi. Hasil penelitian menunjukkan: (1) telah dihasilkan satu produk hasil pengembangan Mobile-Learning materi Ilmu Pengetahuan Lingkungan yaitu Aplikasi Mobile-Learning SARITHA-Apps; (2) Hasil rerata penilaian Tim Ahli terhadap kelayakan instrument dan produk Aplikasi Mobile-Learning SARITHA-Apps adalah 91% yang berarti berada pada kualifikasi “Sangat Layak”; (2) Aplikasi Mobile-Learning SARITHA-Apps mampu meningkatkan hasil belajar mahasiswa untuk materi ilmu pengetahuan lingkungan yaitu dengan N-Gain 0,4 yang berarti berada pada kategori “Sedang”; (3) hasil belajar Mahasiswa menurut kemampuan berpikir kritis dari soal yang diberikan didapati bahwa indikator eksplanasi memiliki nilai peningkatan persentase tertinggi yaitu sebesar 6% dibandingkan dengan peningkatan persentase pada indikator berpikir kritis lainnya, dimana indikator pengaturan diri sebesar 5%, sedangkan indikator analisis dan indikator inferensi sebesar 2%

Tracheobronchomalacia due to amyloidosis in a patient with rheumatoid arthritis

In this case report, we describe a patient with longstanding rheumatoid arthritis who developed tracheobronchomalacia with fatal outcome. Despite negative antemortem biopsies of abdominal fat and tongue, amyloid was found postmortem in the trachea and appeared to be associated with tracheobronchomalacia