1,664 research outputs found
Transition from endemic behavior to eradication of malaria due to combined drug therapies: an agent-model approach
We introduce an agent-based model describing a
susceptible-infectious-susceptible (SIS) system of humans and mosquitoes to
predict malaria epidemiological scenarios in realistic biological conditions.
Emphasis is given to the transition from endemic behavior to eradication of
malaria transmission induced by combined drug therapies acting on both the
gametocytemia reduction and on the selective mosquito mortality during parasite
development in the mosquito. Our mathematical framework enables to uncover the
critical values of the parameters characterizing the effect of each drug
therapy. Moreover, our results provide quantitative evidence of what is
empirically known: interventions combining gametocytemia reduction through the
use of gametocidal drugs, with the selective action of ivermectin during
parasite development in the mosquito, may actively promote disease eradication
in the long run. In the agent model, the main properties of human-mosquito
interactions are implemented as parameters and the model is validated by
comparing simulations with real data of malaria incidence collected in the
endemic malaria region of Chimoio in Mozambique. Finally, we discuss our
findings in light of current drug administration strategies for malaria
prevention, that may interfere with human-to-mosquito transmission process.Comment: 12 pages, 6 figure
PEMBINGKAIAN BERITA KUNJUNGAN PRESIDEN AS BARACK HUSEIN OBAMA DI INDONESIA (Studi Analisis Framing Tentang Berita Kunjungan Presiden AS Barack Husein Obama Pada Surat Kabar Kompas dan Republika edisi 10-11 November 2010 ).
ABSTRAKSI
ERLIA DE JESUS, BERITA KUNJUNGAN PRESIDEN AS BARACK HUSEIN OBAMA DI INDONESIA. (Studi Analisis Framing Tentang Berita Kunjungan Presiden AS Barack Husein Obama 09-11 November 2010 Pada Surat Kabar Kompas dan Republika)
Penelitian ini bertujuan untuk mengetahui bagaimana wartawan membingkai dan mengkontruksi berita-berita tentang kunjungan presiden AS Barack husein Obama di Indonesia untuk itulah digunakan analisis framing sebagai suatu metode analisis teks, yang merupakan metode penelitian kualitatif dengan paragdigma konstruktivis.
Hasil dari penelitian ini, yaitu bahwa surat kabar Kompas lebih menekan Frame mengenai kerja sama bilateral antar RI-AS serta masa kecil Obama di Indonesia. Dalam penulisan berita Kompas lebih menulis pernyataan tentang Obama dan menampilkan pernyataan-pernyataan narasumber berita yang mendukung kerja sama bilateral. Sedangkan surat kabar Republika, dalam penyajian judul maupun beritanya ingin menyampaikan bahwa kujungan Presiden AS Barack Obama mempunyai maksud tertentu dan kerja sama bilateral antara kedua Negara hanya membawa keuntungan semata bagi AS.
Kesimpulan dari penelitian ini adalah pemberitaan pada Kompas terlihat mendukung dan memihak pemerintah AS. Hal ini ditunjukkan Kompas dengan menuliskan kerja sama yang saling menguntungkan antar kedua belah pihak, Kompas juga lebih membahas tentang masa kecil Obama di Indonesia. Sedangkan surat kabar Republika menghadirkan judul dan isi berita yang mengarah pada dugaan bahwa kunjungan Obama hanya membawa keuntungan semata bagi AS.
Kata kunci : Pembingkaian, Berita tentang Kunjungan Presiden AS Barack Obama di Indonesia, Surat Kabar Kompas, Surat Kabar Republika
Impact of physical layer impairments on multi-degree CDC ROADM-based optical networks
Nowadays, optical network nodes are usually based on reconfigurable optical add/drop multiplexers (ROADMs). Due to exponential growth of internet data traffic, ROADMs have evolved to become more flexible, with multi-degree and their add/drop structures are now more complex with enhanced features, such as colorless, directionless and contentionless (CDC). In this work, the impact of in-band crosstalk, optical filtering and amplified spontaneous emission noise on the performance of an optical network based on multi-degree CDC ROADMs is studied considering 100-Gb/s polarisation division multiplexing quadrature phase-shift keying signals for the fixed grid. We show that, an optical signal can pass through a cascade of 19 CDC ROADMs, based on a route and select architecture with 16-degree, until an optical signal-to-noise ratio (OSNR) penalty of 1 dB due to in-band crosstalk is reached. We also show that the ASE noise addition, due to the increase of the number of CDC ROADMs, is more harmful in terms of OSNR penalty than in-band crosstalk.info:eu-repo/semantics/acceptedVersio
CDC ROADM design tradeoffs due to physical layer impairments in optical networks
In this work, we assess the impact of several physical layer impairments (PLIs) on the performance of optical networks based on colorless, directionless and contentionless reconfigurable optical add/drop multiplexers (ROADMs), through Monte-Carlo simulation, and considering polarization division multiplexing 4 and 16 quadrature amplitude modulation (QAM) signals, at 28 GBaud, for 37.5 GHz optical channels. The PLIs taken into account are the amplified spontaneous emission noise, optical filtering, in-band crosstalk and nonlinear interference noise caused by Kerr effect. A detailed model of the ROADM node is built considering two typical ROADM architectures, broadcast and select (B&S) and route and select (R&S), and two different add/drop structures, multicast switches (MCSs) and wavelength selective switches (WSSs), resulting in four different ROADM node scenarios. Our results have shown that for 16QAM signals, the B&S ROADMs with WSSs-based add/drop structures is the scenario that has the best relation cost/performance, foreseeing its use in metro networks, while for 4QAM signals, the R&S ROADM with WSSs-based add/drop structure scenario allows a larger ROADM cascade at an expectable lower cost anticipating its implementation in long-haul networks
Representation of Compact Operators between Banach spaces
In this article, we give a representation for compact operators acting
between reflexive Banach spaces, which generalizes the representation given by
Edmunds et al. for compact operators between reflexive Banach spaces with
strictly convex duals. Further, we give a representation for operators on
Banach spaces that are comparable to compact normal operators on Hilbert spaces
and illustrate our result with an example.Comment: 16 Pages, submitted to a journal. Comments/suggestions are welcom
Structural features and near infra-red (NIR) luminescence of isomeric Yb(iii) bipyridyl-N,N'-dioxide coordination polymers
The synthesis and structural characterization of a series of lanthanide complexes formed from YbX3 salts (X = NO3(-) or CF3SO3(-)) and the isomeric 4,4'-bipyridine-N,N'-dioxide (4,4'-bpdo) or 3,3'-bipyridine-N,N'-dioxide (3,3'-bpdo) ligands has been undertaken by X-ray crystallography. Depending on the choice of anion, the complexes isolated with L = 4,4'-bpdo yield either an extended 1D linear chain {[Yb(L)(NO3)3(CH3OH)]}∞ or a coordination polymer network {[Yb(L)4](CF3SO3)3}∞ which are isostructural with previously reported compounds using other Ln(iii) metals. The isomeric 3,3'-bpdo ligand yields a similar extended 1D linear chain {[Yb(L)(NO3)3(CH3OH)]}∞ when NO3(-) is used as the anion. However, when substituted by the typically non-coordinating CF3SO3(-) anion, inner sphere coordination yields a coordination polymer {[Yb(L)3(CF3SO3)](CF3SO3)2}∞ with a (2(2)·4(8)·6(5)) network topology. In an effort to rationalize the observed difference in coordinating behavior, DFT calculations of the isomeric bipyridyl-N,N'-dioxide ligands have been undertaken, but revealed no significant differences in the charge distribution of the coordinating N-oxide groups. Lastly, sensitized Yb(iii) emission in the Near Infra-Red (NIR) region operating via the well-known antennae effect has been observed and compared for two of the coordination polymers
Structured vs. unstructured scan path in static visual search performance
Call number: LD2668 .T4 1979 S46Master of Scienc
A model for assessing the quantitative effects of heterogeneous affinity in malaria transmission along with Ivermectin mass administration
Using an agent-based model of malaria, we present numerical evidence that in communities of individuals having an affinity varying within a broad range of values, disease transmission may increase up to 300%. Moreover, our findings provide new insight into how to combine different strategies for the prevention of malaria transmission. In particular, we uncover a relationship between the level of heterogeneity and the level of conventional and unconventional anti-malarial drug administration (ivermectin and gametocidal agents), which, when taken together, will define a control parameter, tuning between disease persistence and elimination. Finally, we also provide evidence that the entomological inoculation rate, as well as the product between parasite and sporozoite rates are both good indicators of malaria incidence in the presence of heterogeneity in disease transmission and may configure a possible improvement in that setting, upon classical standard measures such as the basic reproductive number.info:eu-repo/semantics/publishedVersio
Analytical tools for evaluating the impact of in-band crosstalk in DP-QPSK signals
An analytical tool based on the moment generating function of the receiver decision variable that can evaluate the impact of multiple in-band crosstalk signals in DP-QPSK (Dual-Polarization Quadrature Phase-Shift Keying) signals is presented. It is shown that when the number of interferers increases from 1 to 64 the crosstalk level, that assure a 2dB power penalty, becomes more stringent, -12 dB for the single interferer scenario and -15 dB for 64 interferers. The Gaussian approximation is also used for comparison purposes.info:eu-repo/semantics/acceptedVersio
Bacterial expressed coat protein : development of a single antiserum for routine detection of Citrus tristeza virus
Citrus tristeza virus (CTV) causes one of the most important citrus diseases world-wide and has recently
been detected in Portugal. Early diagnosis based on immunoenzymatic techniques requires significant amounts of
reagents. This research describes the isolation of the coat protein gene of CTV, its expression in Escherichia coli as a
fusion protein containing an N-terminal (His)6 region and its use to raise rabbit polyclonal antibodies. These antibodies
could be used at dilutions higher than 1/80,000 at the detection stage in indirect ELISA tests and were also
efficient for trapping the virus in ELISA and Immunocapture RT-PCR. These characteristics allowed the production
of diagnostic kits based solely on this source of antibodies. A detection spectrum and sensitivity similar to that of a
commercial polyclonal antibody kit was achieved
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