213 research outputs found

    Grating coupled photonic crystal demultiplexer with integrated detectors on InP-membrane

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    We report on the successful integration of grating fiber couplers, compact photonic crystal demultiplexers and efficient p-i-n photodetectors on a single bonded InP-membrane chip. Polarization independent operation is obtained by implementing polarization diversity

    Kingdom’s Rights, Kingdom’s Elite: The Case of Prothonotary George Plemić (1690-1713)

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    Autori u radu analiziraju društveno-političke prilike unutar Hrvatskoga Kraljevstva kroz prizmu političke moći i utjecaja protonotara Jurja Plemića u razdoblju od 1690. do 1713. godine, odnosno u razdoblju kada je Juraj Plemić obavljao funkciju kraljevinskoga protonotara. Ističući ovlasti protonotarske funkcije kao i utjecaj osobe koja je obnašala ovu funkciju, autori postavljaju tezu da je protonotar Juraj Plemić bio ključna politička osoba unutar hrvatskoga staleškog svijeta na prijelazu sa 17. na 18. stoljeće i uvelike utjecao na neke od najznačajnijih staleških odluka nastalih unutar institucije Hrvatskoga sabora u navedenom razdoblju.This article analyses the socio-political circumstances within the Kingdom of Croatia between 1690 and 1713, focusing on Prothonotary Juraj Plemić and his political influence as a case study, to illustrate the main thesis that the kingdom’s rights enabled notaries, nobility judges, vicecomites, treasurers, prothonotaries and vice-bans to create a strong political system and to have a monopoly over decision-making in the Croatian Diet, the Sabor, in the aforementioned period. The prothonotary’s political potential and power are explained by the authorities and privileges of prothonotary function as well as the “networking” of parliamentary officials, all of whom belonged to the middle and lower nobility. Consequently, this estate became the privileged negotiation partners within the Kingdom of Croatia for the royal court circles, whereas the magnates’ political activity was severely curtailed. The story of the Samobor copper mine, “the 1708 incident” and the cooperation between the prothonotary and the bishop of Zagreb in legitimising the succession of Habsburg female line all best illustrate the aforementioned influences and “networking” of parliamentary officials, and prove that Prothonotary Plemić was the key political figure of the Croatian estates at the turn of the seventeenth and the eighteenth century. The article emphasises the need for further research into the parliamentary functions and the persons who performed these offices, in order to create new interpretations of early modern Croatian history

    Self-citations at the meso and individual levels: effects of different calculation methods

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    This paper focuses on the study of self-citations at the meso and micro (individual) levels, on the basis of an analysis of the production (1994–2004) of individual researchers working at the Spanish CSIC in the areas of Biology and Biomedicine and Material Sciences. Two different types of self-citations are described: author self-citations (citations received from the author him/herself) and co-author self-citations (citations received from the researchers’ co-authors but without his/her participation). Self-citations do not play a decisive role in the high citation scores of documents either at the individual or at the meso level, which are mainly due to external citations. At micro-level, the percentage of self-citations does not change by professional rank or age, but differences in the relative weight of author and co-author self-citations have been found. The percentage of co-author self-citations tends to decrease with age and professional rank while the percentage of author self-citations shows the opposite trend. Suppressing author self-citations from citation counts to prevent overblown self-citation practices may result in a higher reduction of citation numbers of old scientists and, particularly, of those in the highest categories. Author and co-author self-citations provide valuable information on the scientific communication process, but external citations are the most relevant for evaluative purposes. As a final recommendation, studies considering self-citations at the individual level should make clear whether author or total self-citations are used as these can affect researchers differently

    Reflection from a free carrier front via an intraband indirect photonic transition

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    The reflection of light from moving boundaries is of interest both fundamentally and for applications in frequency conversion, but typically requires high pump power. By using a dispersion-engineered silicon photonic crystal waveguide, we are able to achieve a propagating free carrier front with only a moderate on-chip peak power of 6 W in a 6 ps-long pump pulse. We employ an intraband indirect photonic transition of a co-propagating probe, whereby the probe practically escapes from the front in the forward direction. This forward reflection has up to 35% efficiency and it is accompanied by a strong frequency upshift, which significantly exceeds that expected from the refractive index change and which is a function of group velocity, waveguide dispersion and pump power. Pump, probe and shifted probe all are around 1.5 μm wavelength which opens new possibilities for "on-chip" frequency manipulation and all-optical switching in optical telecommunications

    All-optical routing and switching for three-dimensional photonic circuitry

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    The ability to efficiently transmit and rapidly process huge amounts of data has become almost indispensable to our daily lives. It turned out that all-optical networks provide a very promising platform to deal with this task. Within such networks opto-optical switches, where light is directed by light, are a crucial building block for an effective operation. In this article, we present an experimental analysis of the routing and switching behaviour of light in two-dimensional evanescently coupled waveguide arrays of Y- and T-junction geometries directly inscribed into fused silica using ultrashort laser pulses. These systems have the fundamental advantage of supporting three-dimensional network topologies, thereby breaking the limitations on complexity associated with planar structures while maintaining a high dirigibility of the light. Our results show how such arrays can be used to control the flow of optical signals within integrated photonic circuits

    The correlation and level of agreement between end-tidal and blood gas pCO2 in children with respiratory distress: a retrospective analysis

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    <p>Abstract</p> <p>Background</p> <p>To investigate the correlation and level of agreement between end-tidal carbon dioxide (EtCO<sub>2</sub>) and blood gas pCO<sub>2 </sub>in non-intubated children with moderate to severe respiratory distress.</p> <p>Methods</p> <p>Retrospective study of patients admitted to an intermediate care unit (InCU) at a tertiary care center over a 20-month period with moderate to severe respiratory distress secondary to asthma, bronchiolitis, or pneumonia. Patients with venous pCO<sub>2 </sub>(vpCO<sub>2</sub>) and EtCO<sub>2 </sub>measurements within 10 minutes of each other were eligible for inclusion. Patients with cardiac disease, chronic pulmonary disease, poor tissue perfusion, or metabolic abnormalities were excluded.</p> <p>Results</p> <p>Eighty EtCO<sub>2</sub>-vpCO<sub>2 </sub>paired values were available from 62 patients. The mean ± <smcaps>SD</smcaps> for EtCO<sub>2 </sub>and vpCO<sub>2 </sub>was 35.7 ± 10.1 mmHg and 39.4 ± 10.9 mmHg respectively. EtCO<sub>2 </sub>and vpCO<sub>2 </sub>values were highly correlated (r = 0.90, p < 0.0001). The correlations for asthma, bronchiolitis and pneumonia were 0.74 (p < 0.0001), 0.83 (p = 0.0002) and 0.98 (p < 0.0001) respectively. The mean bias ± <smcaps>SD</smcaps> between EtCO<sub>2 </sub>and vpCO<sub>2 </sub>was -3.68 ± 4.70 mmHg. The 95% level of agreement ranged from -12.88 to +5.53 mmHg. EtCO<sub>2 </sub>was found to be more accurate when vpCO<sub>2 </sub>was 35 mmHg or lower.</p> <p>Conclusion</p> <p>EtCO<sub>2 </sub>is correlated highly with vpCO<sub>2 </sub>in non-intubated pediatric patients with moderate to severe respiratory distress across respiratory illnesses. Although the level of agreement between the two methods precludes the overall replacement of blood gas evaluation, EtCO<sub>2 </sub>monitoring remains a useful, continuous, non-invasive measure in the management of non-intubated children with moderate to severe respiratory distress.</p

    The Evolutionary Genetics and Emergence of Avian Influenza Viruses in Wild Birds

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    We surveyed the genetic diversity among avian influenza virus (AIV) in wild birds, comprising 167 complete viral genomes from 14 bird species sampled in four locations across the United States. These isolates represented 29 type A influenza virus hemagglutinin (HA) and neuraminidase (NA) subtype combinations, with up to 26% of isolates showing evidence of mixed subtype infection. Through a phylogenetic analysis of the largest data set of AIV genomes compiled to date, we were able to document a remarkably high rate of genome reassortment, with no clear pattern of gene segment association and occasional inter-hemisphere gene segment migration and reassortment. From this, we propose that AIV in wild birds forms transient “genome constellations,” continually reshuffled by reassortment, in contrast to the spread of a limited number of stable genome constellations that characterizes the evolution of mammalian-adapted influenza A viruses

    Fish-Specific Duplicated dmrt2b Contributes to a Divergent Function through Hedgehog Pathway and Maintains Left-Right Asymmetry Establishment Function

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    Gene duplication is thought to provide raw material for functional divergence and innovation. Fish-specific dmrt2b has been identified as a duplicated gene of the dmrt2a/terra in fish genomes, but its function has remained unclear. Here we reveal that Dmrt2b knockdown zebrafish embryos display a downward tail curvature and have U-shaped somites. Then, we demonstrate that Dmrt2b contributes to a divergent function in somitogenesis through Hedgehog pathway, because Dmrt2b knockdown reduces target gene expression of Hedgehog signaling, and also impairs slow muscle development and neural tube patterning through Hedgehog signaling. Moreover, the Dmrt2b morphants display defects in heart and visceral organ asymmetry, and, some lateral-plate mesoderm (LPM) markers expressed in left side are randomized. Together, these data indicate that fish-specific duplicated dmrt2b contributes to a divergent function in somitogenesis through Hedgehog pathway and maintains the common function for left-right asymmetry establishment

    Daily egg consumption in hyperlipidemic adults - Effects on endothelial function and cardiovascular risk

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    <p>Abstract</p> <p>Background</p> <p>Limiting consumption of eggs, which are high in cholesterol, is generally recommended to reduce risk of cardiovascular disease. However, recent evidence suggests that dietary cholesterol has limited influence on serum cholesterol or cardiac risk.</p> <p>Objective</p> <p>To assess the effects of egg consumption on endothelial function and serum lipids in hyperlipidemic adults.</p> <p>Methods</p> <p>Randomized, placebo-controlled crossover trial of 40 hyperlipidemic adults (24 women, 16 men; average age = 59.9 ± 9.6 years; weight = 76.3 ± 21.8 kilograms; total cholesterol = 244 ± 24 mg/dL). In the acute phase, participants were randomly assigned to one of the two sequences of a single dose of three medium hardboiled eggs and a sausage/cheese breakfast sandwich. In the sustained phase, participants were then randomly assigned to one of the two sequences of two medium hardboiled eggs and 1/2 cup of egg substitute daily for six weeks. Each treatment assignment was separated by a four-week washout period. Outcome measures of interest were endothelial function measured as flow mediated dilatation (FMD) and lipid panel.</p> <p>Results</p> <p>Single dose egg consumption had no effects on endothelial function as compared to sausage/cheese (0.4 ± 1.9 vs. 0.4 ± 2.4%; <it>p </it>= 0.99). Daily consumption of egg substitute for 6 weeks significantly improved endothelial function as compared to egg (1.0 ± 1.2% vs. -0.1 ± 1.5%; <it>p </it>< 0.01) and lowered serum total cholesterol (-18 ± 18 vs. -5 ± 21 mg/dL; <it>p </it>< 0.01) and LDL (-14 ± 20 vs. -2 ± 19 mg/dL; <it>p </it>= 0.01). Study results (positive or negative) are expressed in terms of change relative to baseline.</p> <p>Conclusions</p> <p>Egg consumption was found to be non-detrimental to endothelial function and serum lipids in hyperlipidemic adults, while egg substitute consumption was beneficial.</p
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