331 research outputs found
Triple-band HTS filter using dual spiral resonators with capacitive-loading
The increasing demand on microwave spectrum for communication systems has been the driving force in the filter industry. Multiple filtering characteristics have become necessary for many filter designs in mobile and satellite applications. In this paper, a new cost-function for an optimization algorithm to achieve a multiple passband filtering function has been introduced. A high-temperature superconductor ten-pole filter with triple-band performance has been designed and fabricated to verify this algorithm. Each of the three passbands has a fractional bandwidth of approximately 0.26%
Dual-band HTS filter using modified dual-spiral resonators
A symmetric dual-band filter with a centre frequency of 887 MHz is presented. The filter uses a modified structure of dual spiral resonators with interdigital capacitive load. At the same resonant frequency, the resonator can occupy an area of less than 2.75% of the area of the square loop resonator. Moreover, the resonator has a very low sensitivity to substrate thickness. The resonator structure also allows two types of couplings and, hence, allows application of cross-couplings with different signs to the direct couplings
Developing a Model of Aged Decellularized Muscle Matrix with Advanced Glycation Cross-linking
Volumetric muscle loss (VML) has been found to overwhelm muscle regeneration, resulting in loss of long-term muscle functionality. Decellularized muscle matrices (DMMs) provide an effective environment for muscle regeneration; however, the age of their source has not been adequately explored for clinical translation. Advanced glycation end-products (AGEs) are chemical cross-links that contribute to the aging process by accumulating on collagen fibers, resulting in a stiffening of the collagenous matrix and an increase in inflammation via the receptor for advanced glycation end-products (RAGE). In previous experiments, we found increased levels of AGE-specific cross-links within DMMs in old mice compared to young as proven by ALT-711 treatment. In this study, we developed a model of aged rat DMMs using AGE cross-links and hypothesized that our AGE-DMM model will contain a higher number of collagen cross-links compared to the control. This AGE-DMM model aims to elucidate the effect of AGEs on muscle regeneration when used in vitro or implanted in a volumetric muscle loss model.https://scholarscompass.vcu.edu/uresposters/1424/thumbnail.jp
Recent advances on time-stretch dispersive Fourier transform and its applications
The need to measure high repetition rate ultrafast processes cuts across multiple areas of science. The last decade has seen tremendous advances in the development and application of new techniques in this field, as well as many breakthrough achievements analyzing non-repetitive optical phenomena. Several approaches now provide convenient access to single-shot optical waveform characterization, including the dispersive Fourier transform (DFT) and time-lens techniques, which yield real-time ultrafast characterization in the spectral and temporal domains, respectively. These complementary approaches have already proven to be highly successful to gain insight into numerous optical phenomena including the emergence of extreme events and characterizing the complexity of laser evolution dynamics. However, beyond the study of these fundamental processes, real-time measurements have also been driven by particular applications ranging from spectroscopy to velocimetry, while shedding new light in areas spanning ultrafast imaging, metrology or even quantum science. Here, we review a number of landmark results obtained using DFT-based technologies, including several recent advances and key selected applications. © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
Two-Body B Meson Decays to and -- Observation of {'}K$
In a sample of 6.6 million produced B mesons we have observed decays B ->
eta' K, with branching fractions BR(B+ -> eta' K+ = 6.5 +1.5 -1.4 +- 0.9) x
and BR(B0 -> eta' K0 = 4.7 +2.7 -2.0 +- 0.9) x . We have
searched with comparable sensitivity for 17 related decays to final states
containing an eta or eta' meson accompanied by a single particle or low-lying
resonance. Our upper limits for these constrain theoretical interpretations of
the B -> eta' K signal.Comment: 12 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Anti-Search for the Glueball Candidate f_J(2220) in Two-Photon Interactions
Using 13.3 fb^{-1} of e^+e^- data recorded with the CLEO II and CLEO II.V
detector configurations at CESR, we have searched for f_J(2220) decays to
K^0_{S} K^0_{S} in untagged two-photon interactions. We report an upper limit
on the product of the two-photon partial width and the branching fraction,
Gamma_gamma gamma cdot B (f_J(2220) to K^0_{S} K^0_{S}) of less than 1.1 eV at
the 95% C.L: systematic uncertainties are included. This dataset is four times
larger than that used in the previous CLEO publication.Comment: 10 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, Submitted to PRD (R
Mixing-induced CP Asymmetries in Radiative B Decays in and beyond the Standard Model
In the Standard Model (SM) the photon in radiative and
decays is predominantly left-handed. Thus, mixing induced CP asymmetries in
and are suppressed by and ,
respectively, and are very small. In many extensions of the SM, such as the
left-right symmetric model (LRSM), SU(2)xU(1) models with exotic fermions and
SUSY, the amplitude of right-handed photons grows proportional to the virtual
heavy fermion mass, which can lead to large asymmetries. As an example, in the
LRSM, asymmetries larger than 50% are possible even when radiative decay rate
measurements agree with SM predictions.Comment: 11 pages + 1 figure.p
The Global Durum Wheat Panel (GDP): An International Platform to Identify and Exchange Beneficial Alleles
Representative, broad and diverse collections are a primary resource to dissect genetic diversity and meet pre-breeding and breeding goals through the identification of beneficial alleles for target traits. From 2,500 tetraploid wheat accessions obtained through an international collaborative effort, a Global Durum wheat Panel (GDP) of 1,011 genotypes was assembled that captured 94-97% of the original diversity. The GDP consists of a wide representation of Triticum turgidum ssp. durum modern germplasm and landraces, along with a selection of emmer and primitive tetraploid wheats to maximize diversity. GDP accessions were genotyped using the wheat iSelect 90K SNP array. Among modern durum accessions, breeding programs from Italy, France and Central Asia provided the highest level of genetic diversity, with only a moderate decrease in genetic diversity observed across nearly 50 years of breeding (1970-2018). Further, the breeding programs from Europe had the largest sets of unique alleles. LD was lower in the landraces (0.4 Mbp) than in modern germplasm (1.8 Mbp) at r 2 = 0.5. ADMIXTURE analysis of modern germplasm defined a minimum of 13 distinct genetic clusters (k), which could be traced to the breeding program of origin. Chromosome regions putatively subjected to strong selection pressure were identified from fixation index (F st ) and diversity reduction index (DRI) metrics in pairwise comparisons among decades of release and breeding programs. Clusters of putative selection sweeps (PSW) were identified as co-localized with major loci controlling phenology (Ppd and Vrn), plant height (Rht) and quality (gliadins and glutenins), underlining the role of the corresponding genes as driving elements in modern breeding. Public seed availability and deep genetic characterization of the GDP make this collection a unique and ideal resource to identify and map useful genetic diversity at loci of interest to any breeding program
Nonperturbative Contributions to the Inclusive Rare Decays and
We discuss nonperturbative contributions to the inclusive rare decays
and . We employ an operator product
expansion and the heavy quark effective theory to compute the leading
corrections to the decay rate found in the free quark decay model, which is
exact in the limit . These corrections are of relative order
, and may be parameterised in terms of two low-energy parameters. We
also discuss the corrections to other observables, such as the average photon
energy in and the lepton invariant mass spectrum in .Comment: 25 pages, 2 figures available upon request, uses harvmac.tex,
SLAC-PUB-6317, UCSD/PTH 93-23, JHU-TIPAC-930020, UTPT 93-19, CMU-HEP 93-12,
DOE-ER/40682-3
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