2,758 research outputs found

    Charge response function and a novel plasmon mode in graphene

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    Polarizability of non-interacting 2D Dirac electrons has a 1/\sqrt{qv-\omega} singularity at the boundary of electron-hole excitations. The screening of this singularity by long-range electron-electron interactions is usually treated within the random phase approximation. The latter is exact only in the limit of N -> infinity, where N is the ``color'' degeneracy. We find that the ladder-type vertex corrections become crucial close to the threshold as the ratio of the n-th order ladder term to the same order RPA contribution is (\ln|qv-\omega|)^n/N^n$. We perform analytical summation of the infinite series of ladder diagrams which describe excitonic effect. Beyond the threshold, qv>\omega, the real part of the polarization operator is found to be positive leading to the appearance of a strong and narrow plasmon resonance.Comment: 4 pages, 3 figures,typos correcte

    Analisis Penerimaan dan Pemahaman Masyarakat terhadap Informasi Izin Mendirikan Bangunan di Kabupaten Maros

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    This study aimed to (1) information conveyed to the public regarding building permits, (2) channel information that is used to convey information building permits, (3) acceptance and understanding of the information society building permits. This study was conducted in Maros. This type of research is survey method with mixed methods approach which is a combination of qualitative methods and quantitative methods. Sampling was done by using simple random sampling of the population who are users of building permits during the year 2013-2014, while informants selected intentionally by certain considerations. Data were collected through questionnaires, interviews, observation and documentation were then analyzed using quantitative descriptive technique. Research results show that: (1) the information submitted regarding the building permits include the prohibition to build without building permits, benefits and purpose building permits, conditions that must be met for the issuance of building permits, maintenance procedures, the time period, the fees as well as sanctions against people who violate building permit, (2) information channels used are billboards, radio, website, brochure, socialization and care workers, (3) acceptance and understanding of the information society of building permits showed a fairly good category in meaning people have to know and understand well enough the importance of building permits before starting the building activity

    Architecting a System Model for Personalized Healthcare Delivery and Managed Individual Health Outcomes

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    In recent years, healthcare needs have shifted from treating acute conditions to meeting an unprecedented chronic disease burden. The healthcare delivery system has structurally evolved to address two primary features of acute care: the relatively short time period, on the order of a patient encounter, and the siloed focus on organs or organ systems, thereby operationally fragmenting and providing care by organ specialty. Much more so than acute conditions, chronic disease involves multiple health factors with complex interactions between them over a prolonged period of time necessitating a healthcare delivery model that is personalized to achieve individual health outcomes. Using the current acute-based healthcare delivery system to address and provide care to patients with chronic disease has led to significant complexity in the healthcare delivery system. This presents a formidable systems’ challenge where the state of the healthcare delivery system must be coordinated over many years or decades with the health state of each individual that seeks care for their chronic conditions. This paper architects a system model for personalized healthcare delivery and managed individual health outcomes. To ground the discussion, the work builds upon recent structural analysis of mass-customized production systems as an analogous system and then highlights the stochastic evolution of an individual’s health state as a key distinguishing feature

    Pengaruh Panjang Serat terhadap Nilai Koefisien Absorpsi Suara dan Sifat Mekanik Komposit Serat Ampas Tebu dengan Matriks Gipsum

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    Penelitian ini dilakukan untuk membuat material komposit gipsum berpenguat serat alam untuk bahan penyerap suara. Permasalahan yang dikaji adalah untuk mengetahui hubungan panjang serat pada komposit ampas tebu bermatrik gipsum terhadap nilai koefisien absorpsi suara (α), kekuatan tekan, dan kekuatan lenturnya. Panjang serat yang digunakan adalah 10mm, 30mm, dan 50mm dengan fraksi volum 30% serat : 70% gipsum. Tujuannya untuk mendapatkan hubungan nilai koefisien absorpsi suara, kuat lentur, dan kuat tekan dengan panjang serat yang diberikan serta aplikasinya dalam material bahan penyerap suara yang memenuhi standar ISO 11654. Metode pembuatan spesimen komposit yang digunakan adalah hand lay up. Metode pengujian berdasarkan standart ASTM E1050 untuk pengujian koefisien absorpsi suara, ASTM D790 untuk pengujian kuat lentur, dan ASTM D695 untuk pengujian kuat tekan. Dari hasil pengujian didapatkan nilai koefisien absorpsi suara memenuhi standar ISO 11654 dengan nilai koefisien α lebih besar dari 0,15. Nilai kuat lentur terbaik ialah pada panjang serat 30mm sebesar 1,952 MPa. Nilai kuat tekan terbaik ialah pada panjang serat 50mm sebesar 2,005 MP

    Efek Pembinaan Disiplin Karyawan dalam Hubungannya dengan Fungsi Public Relation terhadap Kemajuan Carrefour Indonesia di Makassar

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    The study aims to describe the form of disciplinary training of the employees in their public relation function, its influence on, and relationship with the progress of Carrefour Indonesia in Makassar. The study was carried out to the employess of Carrefour Indonesia in Makassar, and the sample was randomly selected. The data were collected through a survey, an audience, and involving questionnaire distribution. The data were analysed with inferential and quantitative descriptive technique. The study proves that the training was carried out in the forms communications activities, i.e. personal communications, counseling, meetings, events, and dialogues. There is a significant correlation between work disciplinary training variables and the company's progress with the strength of association of 0,503, and the positive relationship direction. There is a significant correlation between the independent variables and the dependent ones indicated by the figure 25,3 % which means that there are other Factors (intervening variable) influencing the relationship (74,7 %). The size of the communicator, target, means, and public based on public relation concepts tah is two-way communication and organization communication concept.Keyword ; Disiplin Kerja, Public Relatio

    Pengaruh Panjang Serat terhadap Nilai Koefisien Absorpsi Suara dan Sifat Mekanik Komposit Serat Ampas Tebu dengan Matriks Gipsum

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    Penelitian ini dilakukan untuk membuat material komposit gipsum berpenguat serat alam untuk bahan penyerap suara. Permasalahan yang dikaji adalah untuk mengetahui hubungan panjang serat pada komposit ampas tebu bermatrik gipsum terhadap nilai koefisien absorpsi suara (α), kekuatan tekan, dan kekuatan lenturnya. Panjang serat yang digunakan adalah 10mm, 30mm, dan 50mm dengan fraksi volum 30% serat : 70% gipsum. Tujuannya untuk mendapatkan hubungan nilai koefisien absorpsi suara, kuat lentur, dan kuat tekan dengan panjang serat yang diberikan serta aplikasinya dalam material bahan penyerap suara yang memenuhi standar ISO 11654. Metode pembuatan spesimen komposit yang digunakan adalah hand lay up. Metode pengujian berdasarkan standart ASTM E1050 untuk pengujian koefisien absorpsi suara, ASTM D790 untuk pengujian kuat lentur, dan ASTM D695 untuk pengujian kuat tekan. Dari hasil pengujian didapatkan nilai koefisien absorpsi suara memenuhi standar ISO 11654 dengan nilai koefisien α lebih besar dari 0,15. Nilai kuat lentur terbaik ialah pada panjang serat 30mm sebesar 1,952 MPa. Nilai kuat tekan terbaik ialah pada panjang serat 50mm sebesar 2,005 MP

    The Serological Findings of Parvo virus B19 and Neopterin Detection among Sickle cell Disease Patients and Blood Doners in the Kingdom of Bahrain

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    Introduction. Parvovirus B19 (PV B19) is a small, non-enveloped, ss DNA virus with an icosahedral capsid having a size of 18–26 nm. PV B19 transmits through respiratory droplets, blood transfusion and nosocomial infections that have also been documented recently. The virus targets the actively dividing Erythroid Progenitor Cells (EPCs) that are found in the human bone marrow, fetal liver and human umbilical cord. Methods. The study was particularly conducted on Sickle Cell Disease (SCD) patients and focuses on the determination of parvovirus B19 among Bahraini population by relying on their clinical status. The serological study of PV B19 was performed using Enzyme Linked Immunosorbent Assay (ELISA) technique and includes 150 SCD patientsand 100 healthy blood donors in which both males and females were employed. The samples were taken from the emergency unit of Salmania Medical Complex (SMC) and Ibrahim Khalil Kano Center (IKKC). Results. Of the 150 SCD patients, 100 were with vaso-occlusive crisis(VOC) and 50 non-vaso-occlusive crisis (NVOC). The three groups showed significantly higher percentages of PV B19 IgG but the percentage in SCD was relatively high compared to the control group of age-matched healthy donors – 70% of the VOC patients, 76% of the NVOC cases and 57% of blood donors were found to be IgG sero-positive. Discussion and Conclusion. PV B19 is a pathogenic virus and sometimes considered as life-threatening specifically for those individuals who have SCD due to which a risk of transient aplastic crisis increases. This virus is only associated with those patients whohave some hematological disorders such as hemolytic anemia and erythro-cytopenia. An effective screening test must be performed in the future to reduce the risk of PV B19 infection. Keywords: Aplastic Crisis, Seroprevalence, Bahraini Population, Genotypes, Vasoocclusive crisis, Neopteri
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