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Hendra virus (HeV) is a zoonotic paramyxovirus harbored by Australian mainland flying foxes, from which it is believed to be transmitted directly to horses. In horses, HeV causes a severe, [...]

This paper presents the design and analysis of an SiGe high isolation single-pole double-throw (SPDT) differential absorptive switch at 24 GHz for pulsed ultra-wideband applications. Sub-100-ps envelope rise times are achieved through the use of differential current steering. The SPDT results in 1.9 dB of gain in the passband and an isolation of 35 dB while remaining matched at its ports (absorptive). The measured rise time of the RF envelope is 70 ps using a transistor with an [f.sub.T] of 80 GHz and agrees with both the simulated and analytically determined values. Index Terms--Current mode logic (CML), emitter coupled logic (ECL), RF switches, rise time, silicon-germanium (SiGe), switching speed, ultra-wideband (UWB).

This paper presents the design and measurement of a 12-GHz active phase shifter with an integrated low-noise amplifier in SiGe. The phase is controlled with a 1-bit (180[degrees]) digital phase shifter and a 180[degrees] continuous analog phase shifter. The 1-bit digital phase shifter is implemented by switching between a -90[degrees] low-pass network and a +90[degrees] high-pass network. The analog phase shifter is implemented using a lumped-element loaded line technique where both series and shunt elements are adjusted to continuously vary the phase while maintaining a constant port impedance. Design equations for this constant-impedance phase-shift network are derived and presented. The phase shifter achieves 3.7 [+ or -] 0.5 dB of gain, with a noise figure of 4.4 dB at a center frequency of 11.5 GHz. The total chip size including pads is 1920 [micro]m x 780 [micro]m, and the area of the active circuitry without pads is 1680 [micro]m x 660 [micro]m (1.1 [mm.sup.2]). Index Terms--All-pass networks, direct broadcast satellite (DBS), phased arrays, phase shifters, RF integrated circuit (RFIC), satellite communications, silicon germanium.

High-efficiency monolithic SiGe balanced frequency doublers have been developed for Ku- and Ka-band applications. A novel miniature second harmonic reflector is presented, and the impact of the parasitic inductor from emitter to ground is also explored to optimize the conversion efficiency of the doubler. The Ku-band design presents an output power of 5-6 dBm from 15.4-18 GHz for an input power of 1.5 dBm. DC power consumption is 28 mW and the corresponding power-added efficiency (PAE) is 9.2%. The Ka-band design demonstrates an output power of 10.5 dBm at 36 GHz for an input power of 6 dBm while consuming 114 mW of dc power, which results in a PAE of 6.4%. It also shows high spectral purity operation with the fundamental suppression of 35 dB. To our knowledge, these are the best results for active doublers using any technology. Index Terms--Balanced frequency doubler, high efficiency, high power, high spectral purity, monolithic microwave integrated circuit (MMIC), SiGe.

The Rosenberg Self-Esteem Scale, a widely used self-report instrument for evaluating individual self-esteem, was investigated using item response theory. Factor analysis identified a single common factor, contrary to some previous studies that extracted separate Self-Confidence and Self-Depreciation factors. A unidimensional model for graded item responses was fit to the data. A model that constrained the 10 items to equal discrimination was contrasted with a model allowing the discriminations to be estimated freely. The test of significance indicated that the unconstrained model better fit the data--that is, the 10 items of the Rosenberg Self-Esteem Scale are not equally discriminating and are differentially related to self-esteem. The pattern of functioning of the items was examined with respect to their content, and observations are offered with implications for validating and developing future personality instruments., The concept of self plays a central role in theory and research in psychology; and self-esteem, the evaluative component of the self-concept, is one of the most frequently measured constructs [...]

Abstract Background This paper considers the problem of identifying pathways through metabolic networks that relate to a specific biological response. Our proposed model, HME3M, first identifies frequently traversed network paths using a Markov mixture model. Then by employing a hierarchical mixture of experts, separate classifiers are built using information specific to each path and combined into an ensemble prediction for the response. Results We compared the performance of HME3M with logistic regression and support vector machines (SVM) for both simulated pathways and on two metabolic networks, glycolysis and the pentose phosphate pathway for Arabidopsis thaliana. We use AltGenExpress microarray data and focus on the pathway differences in the developmental stages and stress responses of Arabidopsis. The results clearly show that HME3M outperformed the comparison methods in the presence of increasing network complexity and pathway noise. Furthermore an analysis of the paths identified by HME3M for each metabolic network confirmed known biological responses of Arabidopsis. Conclusions This paper clearly shows HME3M to be an accurate and robust method for classifying metabolic pathways. HME3M is shown to outperform all comparison methods and further is capable of identifying known biologically active pathways within microarray data.

Background: Enhancers are non-coding DNA sequences, which when they are bound by specific proteins increase the level of gene transcription. Enhancers activate unique gene expression patterns within cells of different types or under different conditions. Enhancers are key contributors to gene regulation, and causative variants that affect quantitative traits in humans and mice have been located in enhancer regions. However, in the bovine genome, enhancers as well as other regulatory elements are not yet well defined. In this paper, we sought to improve the annotation of bovine enhancer regions by using publicly available mammalian enhancer information. To test if the identified putative bovine enhancer regions are enriched with functional variants that affect milk production traits, we performed genome-wide association studies using imputed whole-genome sequence data followed by meta-analysis and enrichment analysis. Results: We produced a library of candidate bovine enhancer regions by using publicly available bovine ChIP-Seq enhancer data in combination with enhancer data that were identified based on sequence homology with human and mouse enhancer databases. We found that imputed whole-genome sequence variants associated with milk production traits in 16,581 dairy cattle were enriched with enhancer regions that were marked by bovine-liver H3K4me3 and H3K27ac histone modifications from both permutation tests and gene set enrichment analysis. Enhancer regions that were identified based on sequence homology with human and mouse enhancer regions were not as strongly enriched with trait-associated sequence variants as the bovine ChIP-Seq candidate enhancer regions. The bovine ChIP-Seq enriched enhancer regions were located near genes and quantitative trait loci that are associated with pregnancy, growth, disease resistance, meat quality and quantity, and milk quality and quantity traits in dairy and beef cattle. Conclusions: Our results suggest that sequence variants within enhancer regions that are located in bovine noncoding genomic regions contribute to the variation in complex traits. The level of enrichment was higher in bovinespecific enhancer regions that were identified by detecting histone modifications H3K4me3 and H3K27ac in bovine liver tissues than in enhancer regions identified by sequence homology with human and mouse data. These results highlight the need to use bovine-specific experimental data for the identification of enhancer regions. [ABSTRACT FROM AUTHOR]