1,087 research outputs found

    Space-time trellis code construction for fast fading channels

    Full text link
    Abstract—The need for bandwidth- and power-efficient wireless communication systems has raised considerable interest in space-time codes. In this work, we propose a systematic space-time code construction procedure for fast fading channels. The method can be used to design space-time codes for an arbitrary number of transmit antennas and any memoryless modulation. We introduce a new design criterion that ensures full spatial diversity and de-velop the code design method based on this criterion. The flexibil-ity of the proposed approach is demonstrated by designing space-time trellis codes for 2, 3 and 4 transmit antennas with QPSK, 8PSK and 4ASK modulations. I

    First-Order Melting of a Moving Vortex Lattice: Effects of Disorder

    Full text link
    We study the melting of a moving vortex lattice through numerical simulations with the current driven 3D XY model with disorder. We find that there is a first-order phase transition even for large disorder when the corresponding equilibrium transition is continuous. The low temperature phase is an anisotropic moving glass.Comment: Important changes from original version. Finite size analysis of results has been added. Figure 2 has been changed. There is a new additional Figure. To be published in Physical Review Letter

    Osteosarcoma of the femur in early adult: a case report

    Get PDF
    Osteosarcomas are primary malignant tumors of bone that are characterized by the production of osteoid or immature bone by the malignant cells. Osteosarcomas are uncommon tumors. Most articles reveal difficulty in diagnosing osteosarcoma in early stage due to its resemblance to benign lesion. That’s why we prefer to do case report for documentation. Diagnosis of the tumor is important especially in early stages for improving prognosis. This case report is of a 21 years old female who presented at Primary Health Care Centre with swelling above right knee post trauma a month ago. Previously she was diagnosed as Non ossifying fibroma (which is a benign lesion and uncommon to change to malignant lesion) at the same site in 2017.

    Energy cost associated with vortex crossing in superconductors

    Full text link
    Starting from the Ginzburg-Landau free energy of a type II superconductor in a magnetic field we estimate the energy associated with two vortices crossing. The calculations are performed by assuming that we are in a part of the phase diagram where the lowest Landau level approximation is valid. We consider only two vortices but with two markedly different sets of boundary conditions: on a sphere and on a plane with quasi-periodic boundary conditions. We find that the answers are very similar suggesting that the energy is localised to the crossing point. The crossing energy is found to be field and temperature dependent -- with a value at the experimentally measured melting line of U×≃7.5kTm≃1.16/cL2U_\times \simeq 7.5 k T_m \simeq 1.16/c_L^2, where cLc_L is the Lindemann melting criterion parameter. The crossing energy is then used with an extension of the Marchetti, Nelson and Cates hydrodynamic theory to suggest an explanation of the recent transport experiments of Safar {{\em et al.}\ }.Comment: 15 pages, RevTex v3.0, followed by 5 postscript figure

    ASPIRASI PEREMPUAN DALAM PEMBENTUKAN PERATURAN DAERAH PROVINSI SULAWESI TENGGARA PERIODE 2014-2019 (Studi Pada Kantor DPRD Sulawesi Tenggara)

    Get PDF
    Abstrak: Tujuan penelitian ini: (1) untuk mengetahui aspirasi perempuan dalam pembentukan peraturan daerah di Provinsi Sulawesi Tenggara, (2)untuk mengetahui hambatan-hambatan apa yang dihadapi perempuan dalam memperjuangkan aspirasi perempuan di DPRD Provinsi Sulawesi Tenggara. Metode penelitian ini adalah kualitatif. Subyek penelitian ini adalah perempuan yang menjadi anggota legislatif di DPRD Provinsi Sulawesi Tenggara Periode 2014-2019 dan informan ketua DPRD, sekretaris DPRD, pimpinan fraksi, dan LSM. Teknik analisis data adalah deskriptif kualitatif. Hasil penelitian menunjukkan bahwa hanya terdapat 1 (satu) aspirasi perempuan yang menjadi produk legislatif Periode 2014-2019. Namun dalam peraturan daerah tersebut telah memuat berbagai aspek aspirasi perempuan terkait dengan perlindungan perempuan yakni hak-hak perempuan sebagai korban kekerasan baik sebagai tindakan pencegahan dan penanganan yang melibatkan tanggung jawab pemerintah, partisipasi masyarakat dan aparat hukum. Adapun aspirasi perempuan meliputi penciptaan rasa aman, hak perempuan sebagai korban berbagai bentuk perlindungan dan tanggung jawab pihak pemerintah. Namun demikian, masih terdapat berbagai hambatan yang dijumpai yang bekum dilakukan oleh lembaga legislatif DPRD Provinsi Sulawesi Tenggara Periode 2014-2019 dalam memperjuangkan aspirasi perempuan di berbagai sektor kehidupan sosial masyarakat seperti kendala masih kurangnya anggota legislatif perempuan, latar belakang pembentukan peraturan daerah DPRD Provinsi Sulawesi Tenggara anggota legislatif perempuan yang belum mengakomodir aktivis gerakan perempuan dan belum terbangunnya hubungan permanen antara legislatif dengan lembaga sosial gerakan perempuan. Kesimpulan penelitian ini adalah aspirasi perempuan di lembaga DPRD Provinsi Sulawesi Tenggara Periode 2014-2019 belum maksimal dan hanya terdapat 1 (satu) aspirasi perempuan  yang menjadi produk aspirasi perempuan DPRD Provinsi Sulawesi Tenggara. Hambatan upaya pemenuhan aspirasi perempuan di DPRD Provinsi Sulawesi Tenggara adalah keterbatasan jumlah anggota legislatif perempuan, latar belakang sosial, dan penjaringan aspirasi perempuan.Kata Kunci: Aspirasi Perempuan, Pembentukan Peraturan Daerah, DPRD Provinsi Sulawesi Tenggar

    First-Order Vortex Lattice Melting and Magnetization of YBa2_2Cu3_3O$_{7-\delta}

    Full text link
    We present the first non-mean-field calculation of the magnetization M(T)M(T) of YBa2_2Cu3_3O7−δ_{7-\delta} both above and below the flux-lattice melting temperature Tm(H)T_m(H). The results are in good agreement with experiment as a function of transverse applied field HH. The effects of fluctuations in both order parameter ψ(r)\psi({\bf r}) and magnetic induction BB are included in the Ginzburg-Landau free energy functional: ψ(r)\psi({\bf r}) fluctuates within the lowest Landau level in each layer, while BB fluctuates uniformly according to the appropriate Boltzmann factor. The second derivative (∂2M/∂T2)H(\partial^2 M/\partial T^2)_H is predicted to be negative throughout the vortex liquid state and positive in the solid state. The discontinuities in entropy and magnetization at melting are calculated to be ∼0.034 kB\sim 0.034\, k_B per flux line per layer and ∼0.0014\sim 0.0014~emu~cm−3^{-3} at a field of 50 kOe.Comment: 11 pages, 4 PostScript figures in one uuencoded fil

    Genetic diversity and low stratification of the population of the United Arab Emirates

    Get PDF
    © Copyright © 2020 Tay, Henschel, Daw Elbait and Al Safar. With high consanguinity rates on the Arabian Peninsula, it would not have been unexpected if the population of the United Arab Emirates (UAE) was shown to be relatively homogenous. However, this study of 1000 UAE nationals provided a contrasting perspective, one of a relatively heterogeneous population. Located at the apex of Europe, Asia, and Africa, the observed diversity could be explained by a plethora of migration patterns since the first Out-of-Africa movement. A strategy to explore the extent of genetic variation of the population of the UAE is presented. The first step involved a comprehensive population stratification study that was instructive for subsequent whole genome sequencing (WGS) of suitable representatives (which is described elsewhere). When these UAE data were compared to previous smaller studies from the region, the findings were consistent with a population that is a diverse and admixed group of people. However, rather than sharp and distinctive clusters, cluster analysis reveals low levels of stratification throughout the population. UAE emirates exhibit high within-Emirate-distance/among-Emirate distance ratios. Supervised admixture analysis showed a continuous gradient of ancestral populations, suggesting that admixture on the south eastern tip of the Arabian Peninsula occurred gradually. When visualized using a unique technique that combined admixture ratios and principal component analysis (PCA), unappreciated diversity was revealed while mitigating projection bias of conventional PCA. We observe low population stratification in the UAE in terms of homozygosity versus separation cluster coefficients. This holds for the UAE in a global context as well as for isolated cluster analysis of the Emirati birthplaces. However, the subtle clustering observed in the Emirates reflects geographic proximity and historic migration events. The analytical strategy used here highlights the complementary nature of data from genotype array and WGS for anthropological studies. Specifically, genotype array data were instructive to select representative subjects for WGS. Furthermore, from the 2.3 million allele frequencies obtained from genotype arrays, we identified 46,481 loci with allele frequencies that were significantly different with respect to other world populations. This comparison of allele frequencies facilitates variant prioritization in common diseases. In addition, these loci bear great potential as biomarkers in anthropological and forensic studies

    A population-specific major allele reference genome from the United Arab Emirates population

    Get PDF
    The ethnic composition of the population of a country contributes to the uniqueness of each national DNA sequencing project and, ideally, individual reference genomes are required to reduce the confounding nature of ethnic bias. This work represents a representative Whole Genome Sequencing effort of an understudied population. Specifically, high coverage consensus sequences from 120 whole genomes and 33 whole exomes were used to construct the first ever population specific major allele reference genome for the United Arab Emirates (UAE). When this was applied and compared to the archetype hg19 reference, assembly of local Emirati genomes was reduced by ∼19% (i.e., some 1 million fewer calls). In compiling the United Arab Emirates Reference Genome (UAERG), sets of annotated 23,038,090 short (novel: 1,790,171) and 137,713 structural (novel: 8,462) variants; their allele frequencies (AFs) and distribution across the genome were identified. Population-specific genetic characteristics including loss-of-function variants, admixture, and ancestral haplogroup distribution were identified and reported here. We also detect a strong correlation between F and admixture components in the UAE. This baseline study was conceived to establish a high-quality reference genome and a genetic variations resource to enable the development of regional population specific initiatives and thus inform the application of population studies and precision medicine in the UAE. S

    Whole genome sequencing of four representatives from the admixed population of the United Arab Emirates

    Get PDF
    © Copyright © 2020 Daw Elbait, Henschel, Tay and Al Safar. Whole genome sequences (WGS) of four nationals of the United Arab Emirates (UAE) at an average coverage of 33X have been completed and described. The selection of suitable subpopulation representatives was informed by a preceding comprehensive population structure analysis. Representatives were chosen based on their central location within the subpopulation on a principal component analysis (PCA) and the degree to which they were admixed. Novel genomic variations among the different subgroups of the UAE population are reported here. Specifically, the WGS analysis identified 4,161,067–4,798,806 variants in the four individual samples, where approximately 80% were single nucleotide polymorphisms (SNPs) and 20% were insertions or deletions (indels). An average of 2.75% was found to be novel variants according to dbSNP (build 151). This is the first report of structural variants (SV) from WGS data from UAE nationals. There were 15,677–20,339 called SVs, of which around 13.5% were novel. The four samples shared 1,399,178 variants, each with distinct variants as follows: 1,085,524 (for the individual denoted as UAE S011), 1,228,559 (UAE S012), 791,072 (UAE S013), and 906,818 (UAE S014). These results show a previously unappreciated population diversity in the region. The synergy of WGS and genotype array data was demonstrated through variant annotation of the former using 2.3 million allele frequencies for the local population derived from the latter technology platform. This novel approach of combining breadth and depth of array and WGS technologies has guided the choice of population genetic representatives and provides complementary, regionalized allele frequency annotation to new genomes comprising millions of loci
    • …
    corecore