35,459 research outputs found

    Bit error simulation of DQPSK for a slow frequency hopping CDMA system in mobile radio communications

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    Independent stratum formation on the avian sex chromosomes reveals inter-chromosomal gene conversion and predominance of purifying selection on the w chromosome

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    We used a comparative approach spanning three species and 90 million years to study the evolutionary history of the avian sex chromosomes. Using whole transcriptomes, we assembled the largest cross-species dataset of W-linked coding content to date. Our results show that recombination suppression in large portions of the avian sex chromosomes has evolved independently, and that long-term sex chromosome divergence is consistent with repeated and independent inversions spreading progressively to restrict recombination. In contrast, over short-term periods we observe heterogeneous and locus-specific divergence. We also uncover four instances of gene conversion between both highly diverged and recently evolved gametologs, suggesting a complex mosaic of recombination suppression across the sex chromosomes. Lastly, evidence from 16 gametologs reveal that the W chromosome is evolving with a significant contribution of purifying selection, consistent with previous findings that W-linked genes play an important role in encoding sex-specific fitness

    The politics of government reform in Korea : from tripartite to bipartite politicization

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    Government reforms in South Korea, beginning in the 1980s, moved toward deconcentration and deregulation in the 1990s and 2000s. However, the contents of the reforms under the “transformational” presidencies following democratization, which aimed to raise the quality of government and respond to increasing social polarization and political discord, did not significantly reduce state power or depoliticize policy making. Instead, state strength was consolidated through tripartite politicization: the rise of ministers as a third force in policy making vis-à-vis the president and legislature. Under the “post-transformational” presidencies of Lee Myung-Bak and Park Geun-Hye, government reforms can be summarized as bipartite politicization between the president and legislature, as ministerial power has been reduced

    State political and economic capacities and the quality of government in Asia

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    This study analyzes the impacts of state political and economic capacities on the quality of government in 40 Asian countries. Quality of government data for 2002 and 2010 were obtained from four elements of the World Bank Governance Index, and the same or closest year's data for political and economic capacity were collected from other well-known indices. The analysis reveals that economic growth influences four elements in both developed and developing countries, although the effects of economic freedom differ between these two groups of states. While political capacity (i.e. civil empowerment, democracy, and press freedom) is found to have an effect on all four of the governance elements in developed countries, it influences just two elements in developing economies. Thus, the results suggest that the quality of government in Asia is not only improved by economic capacity but might also be enhanced by consolidation of democracy, particularly once a certain degree of economic development is achieved

    Medical Malpractice in Cardiovascular Surgery; Cases Referred to Tehran Forensic Medicine Organization during 2011-13

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    Background: Cardiovascular surgeries are a most common and important surgeries in Iran and because of its high risk nature, the outcome is not always satisfactory, so could lead to a complaint. In recent years, there has been an increase in complaints against cardiovascular surgeons. Aim of current study was to determine the frequency of medical malpractice in the field of cardiovascular surgery in the cases referred to the Tehran forensic medicine commission.Methods: In this retrospective cross-sectional study, all malpractice cases referred to the forensic medicine commissions in Tehran with regard to the field of cardiovascular surgery during 2011-2013 were collected. Information such as age, sex, type of hospital (state or private), type of cardiosurgery, type of malpractice, percentage of malpractice, cause of death, and background diseases were extracted and then analyzed.Results: Of the 56 cases, the frequency of malpractice was 27 cases (48.2 %) and the most important type of malpractice was negligence (32.2%) and the majority of cases were related to private centers. The most common malpractice was related to coronary artery disease and the main cause of complaint was the patient death (76.8%). 54.5% of malpractice rate was in men and in patients older than 60 years (67%) which was higher than other age groups. There was no significant association between age and sex with malpractice.Conclusion: Despite improvement in medical technology and the use of advanced techniques in the diagnosis and treatment, the complaint rate of cardiovascular surgeons is increasing. In addition to optimizing cardiovascular surgical techniques, informing the patient and his/her companions about the side effects of these high risk surgeries can be effective in prevention of malpractice and physician mistakes

    Mechanisms of dysregulation of low-density lipoprotein receptor expression in vascular smooth muscle cells by inflammatory cytokines

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    Objective - Although inflammation is a recognized feature of atherosclerosis, the impact of inflammation on cellular cholesterol homeostasis is unclear. This study focuses on the molecular mechanisms by which inflammatory cytokines disrupt low-density lipoprotein (LDL) receptor regulation.Methods and Results - IL-1 beta enhanced transformation of vascular smooth muscle cells into foam cells by increasing uptake of unmodified LDL via LDL receptors and by enhancing cholesterol esterification as demonstrated by Oil Red O staining and direct assay of intracellular cholesterol concentrations. In the absence of IL-1 beta, a high concentration of LDL decreased LDL receptor promoter activity, mRNA synthesis and protein expression. However, IL-1 beta enhanced LDL receptor expression, overriding the suppression usually induced by a high concentration of LDL and inappropriately increasing LDL uptake. Exposure to IL-1 beta also caused overexpression of the sterol regulatory element binding protein ( SREBP) cleavage-activating protein ( SCAP), and enhanced its translocation from the endoplasmic reticulum to the Golgi, where it is known to cleave SREBP, thereby enhancing LDL receptor gene expression.Conclusions - These observations demonstrate that IL-1 beta disrupts cholesterol-mediated LDL receptor feedback regulation, permitting intracellular accumulation of unmodified LDL and causing foam cell formation. The implication of these findings is that inflammatory cytokines may contribute to intracellular LDL accumulation without previous modification of the lipoprotein

    Short Communication: Effects of Temperature and Relative Humidity on the Egg Laying Pattern of Rhipicephalussanguineus (koch, 1844) Infesting Goats in Maiduguri

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    No Abstract. KEY WORDS: Temperature, Relative H u m i d i t y , E g g Laying,Rhipicephalussanguineu

    LSD1 is essential for oocyte meiotic progression by regulating CDC25B expression in mice

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    Mammalian oocytes are arrested at prophase I until puberty when hormonal signals induce the resumption of meiosis I and progression to meiosis II. Meiotic progression is controlled by CDK1 activity and is accompanied by dynamic epigenetic changes. Although the signalling pathways regulating CDK1 activity are well defined, the functional significance of epigenetic changes remains largely unknown. Here we show that LSD1, a lysine demethylase, regulates histone H3 lysine 4 di-methylation (H3K4me2) in mouse oocytes and is essential for meiotic progression. Conditional deletion of Lsd1 in growing oocytes results in precocious resumption of meiosis and spindle and chromosomal abnormalities. Consequently, most Lsd1-null oocytes fail to complete meiosis I and undergo apoptosis. Mechanistically, upregulation of CDC25B, a phosphatase that activates CDK1, is responsible for precocious meiotic resumption and also contributes to subsequent spindle and chromosomal defects. Our findings uncover a functional link between LSD1 and the major signalling pathway governing meiotic progression

    Tinjauan Hukum Islam Terhadap Praktek Akad Pembiayaan Ijarah (Studi Kasus di BMT Al-Madinah Jajar Laweyan Surakarta)

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    Praktek Ijārah yaitu penjualan manfaat atau salah satu bentuk aktivitas antara dua belah pihak yang berakad guna meringankan salah satu pihak atau saling meringankan, serta termasuk salah satubentuk tolong menolong yang diperintahkan oleh agama. Dalam fiqih islam Ijārah memeberikan sesuatu untuk disewakan, menurut fatwa DSN ijarah didefinisikan sebagai akad pemindahan hak guna(manfaat) atas suatu barang dalam waktu tertentu dengan sewa, tanpa diikuti dengan pemindahan barang itu sendiri. Di dalam penetapan ujroh yang ada di BMT Al-Madinah Jajar Laweyan Surakarta dimana dalam pambagiannya tersebut dengan menggunakan hasil kesepakatan oleh kedua belah pihak yang ada di BMT tesebut, sehingga menjadi peluang peneliti untuk obyek kajian penelitian yang dapat memberikan kontribusi pemikiran dalam bidang Ijārah, khususnya bagi para pelaku praktek yang menggunakan Akad Ijarah. Tujuan dari penelitian ini adalah sebagai berikut: (1) Mengetahui praktek akad pembiayaan Ijārah dalam pembagian ujroh yang ada di BMT Al-Madinah jajar laweyan surakarta. (2) Mengetahui tinjauan hukum Islam terhadap praktek akad pembiayaan ijarah. Penelitaian ini adalah penelitian lapangan (field research ) dengan pendektan kualitatif. Metode yang digunakan dalam pengumpulan data adalah dengan cara wawancara dan dokumentasi. Analisis yang digunakan adalah metode Deduktif dan metode Induktif. Berdasarkan penelitian akad Ijarah yang ada di BMT Al-Madinah Jajar Laweyan Surakarta, pelaksanaan praktek akad pembiayaan Ijārah terdapat dua hukum pertama pada pembiayaan pendidikan dan pembiayaan rumah sakit belum memenuhi syarat berdasarkan konsep ijārah, karna kejelasan barang yang ditransaksikan bukan barang atau jasa akan tetapi berbentuk uang. Kedua pada pembiayaan gedung pengantin sudah sesuai dengan syariah, rukun dan syaratnya sudah terpenuhi meskipun ada pihak penyedia jasa akan tetapi tidak mengurangi dalam kecacatan hukum. Kata Kunci: Ijārah, Akad, Hukum Islam
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