164 research outputs found
Interception and demodulation of slow frequency-hopped differential phase shift keyed signals using envelope detection and pattern recognition
This thesis presents a novel non-coherent wireless communication receiver design for intercepting and demodulating frequency hopping spread spectrum (FHSS) signals. This interception receiver is based upon phase modulation to amplitude modulation conversion (PM to AM), and is specifically designed for demodulating a slow frequency-hopped signal that has differentially encoded phase shift keying (DPSK) modulation. The receiver will also demodulate non-frequency hopped DPSK signals. Matlab(Superscript Trade Mark Symbol) simulations show that if a signal has a signal to noise ratio (SNR) greater than approximately 30 dB, the intercept receiver can demodulate it by using the following: a bank of filters for PM to AM conversion, envelope detectors for each filter in the bank, and a pattern recognition algorithm that processes the envelope detector outputs, combines them, and maps the result into bits. The performance of the receiver is characterized with simulations and analytical calculations
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Vitamin D Modulates Expression of the Airway Smooth Muscle Transcriptome in Fatal Asthma
Globally, asthma is a chronic inflammatory respiratory disease affecting over 300 million people. Some asthma patients remain poorly controlled by conventional therapies and experience more life-threatening exacerbations. Vitamin D, as an adjunct therapy, may improve disease control in severe asthma patients since vitamin D enhances glucocorticoid responsiveness and mitigates airway smooth muscle (ASM) hyperplasia. We sought to characterize differences in transcriptome responsiveness to vitamin D between fatal asthma- and non-asthma-derived ASM by using RNA-Seq to measure ASM transcript expression in five donors with fatal asthma and ten non-asthma-derived donors at baseline and with vitamin D treatment. Based on a Benjamini-Hochberg corrected p-value <0.05, 838 genes were differentially expressed in fatal asthma vs. non-asthma-derived ASM at baseline, and vitamin D treatment compared to baseline conditions induced differential expression of 711 and 867 genes in fatal asthma- and non-asthma-derived ASM, respectively. Functional gene categories that were highly represented in all groups included extracellular matrix, and responses to steroid hormone stimuli and wounding. Genes differentially expressed by vitamin D also included cytokine and chemokine activity categories. Follow-up qPCR and individual analyte ELISA experiments were conducted for four cytokines (i.e. CCL2, CCL13, CXCL12, IL8) to measure TNFα-induced changes by asthma status and vitamin D treatment. Vitamin D inhibited TNFα-induced IL8 protein secretion levels to a comparable degree in fatal asthma- and non-asthma-derived ASM even though IL8 had significantly higher baseline levels in fatal asthma-derived ASM. Our findings identify vitamin D-specific gene targets and provide transcriptomic data to explore differences in the ASM of fatal asthma- and non-asthma-derived donors
Cerebellar gray and white matter volume and their relation with age and manual motor performance in healthy older adults
ObjectivesFunctional neuroimaging and voxel‐based morphometry studies have confirmed the important role of the cerebellum in motor behavior. However, little is known about the relationship between cerebellar gray (GMv) and white matter (WMv) volume and manual motor performance in aging individuals. This study aims to quantify the relationship between cerebellar tissue volume and manual motor performance.Experimental designTo gain more insight into cerebellar function and how it relates to the role of the primary motor cortex (M1), we related cerebellar GMv, WMv, and M1v to manual motor performance in 217 healthy older individuals. Left and right cerebellar GMv and WMv, and M1v were obtained using FreeSurfer. The following motor measures were obtained: grip force, tapping speed, bimanual visuomotor coordination, and manual dexterity.Principal observationsSignificant positive relationships were observed between cerebellar GMv and WMv and grip strength, right cerebellar WMv and right‐hand tapping speed, right cerebellar WMv and dexterity, M1v and grip strength, and right M1v and left‐hand dexterity, though effect sizes were small.ConclusionsOur results show that cerebellar GMv and WMv are differently associated with manual motor performance. These associations partly overlap with the brain‐behavior associations between M1 and manual motor performance. Not all observed associations were lateralized (i.e., ipsilateral cerebellar and contralateral M1v associations with motor performance), which could point to age‐related neural dedifferentiation. The current study provides new insights in the role of the cerebellum in manual motor performance. In consideration of the small effect sizes replication studies are needed to validate these results. Hum Brain Mapp 36:2352–2363, 2015. © 2015 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111082/1/hbm22775.pd
The adaptor molecule CARD9 is essential for tuberculosis control
The cross talk between host and pathogen starts with recognition of bacterial signatures through pattern recognition receptors (PRRs), which mobilize downstream signaling cascades. We investigated the role of the cytosolic adaptor caspase recruitment domain family, member 9 (CARD9) in tuberculosis. This adaptor was critical for full activation of innate immunity by converging signals downstream of multiple PRRs. Card9−/− mice succumbed early after aerosol infection, with higher mycobacterial burden, pyogranulomatous pneumonia, accelerated granulocyte recruitment, and higher abundance of proinflammatory cytokines and granulocyte colony-stimulating factor (G-CSF) in serum and lung. Neutralization of G-CSF and neutrophil depletion significantly prolonged survival, indicating that an exacerbated systemic inflammatory disease triggered lethality of Card9−/− mice. CARD9 deficiency had no apparent effect on T cell responses, but a marked impact on the hematopoietic compartment. Card9−/− granulocytes failed to produce IL-10 after Mycobaterium tuberculosis infection, suggesting that an absent antiinflammatory feedback loop accounted for granulocyte-dominated pathology, uncontrolled bacterial replication, and, ultimately, death of infected Card9−/− mice. Our data provide evidence that deregulated innate responses trigger excessive lung inflammation and demonstrate a pivotal role of CARD9 signaling in autonomous innate host defense against tuberculosis
Achieving a quantum smart workforce
Interest in building dedicated Quantum Information Science and Engineering
(QISE) education programs has greatly expanded in recent years. These programs
are inherently convergent, complex, often resource intensive and likely require
collaboration with a broad variety of stakeholders. In order to address this
combination of challenges, we have captured ideas from many members in the
community. This manuscript not only addresses policy makers and funding
agencies (both public and private and from the regional to the international
level) but also contains needs identified by industry leaders and discusses the
difficulties inherent in creating an inclusive QISE curriculum. We report on
the status of eighteen post-secondary education programs in QISE and provide
guidance for building new programs. Lastly, we encourage the development of a
comprehensive strategic plan for quantum education and workforce development as
a means to make the most of the ongoing substantial investments being made in
QISE.Comment: 18 pages, 2 figures, 1 tabl
RNA-Seq of Human Neurons Derived from iPS Cells Reveals Candidate Long Non-Coding RNAs Involved in Neurogenesis and Neuropsychiatric Disorders
Genome-wide expression analysis using next generation sequencing (RNA-Seq) provides an opportunity for in-depth molecular profiling of fundamental biological processes, such as cellular differentiation and malignant transformation. Differentiating human neurons derived from induced pluripotent stem cells (iPSCs) provide an ideal system for RNA-Seq since defective neurogenesis caused by abnormalities in transcription factors, DNA methylation, and chromatin modifiers lie at the heart of some neuropsychiatric disorders. As a preliminary step towards applying next generation sequencing using neurons derived from patient-specific iPSCs, we have carried out an RNA-Seq analysis on control human neurons. Dramatic changes in the expression of coding genes, long non-coding RNAs (lncRNAs), pseudogenes, and splice isoforms were seen during the transition from pluripotent stem cells to early differentiating neurons. A number of genes that undergo radical changes in expression during this transition include candidates for schizophrenia (SZ), bipolar disorder (BD) and autism spectrum disorders (ASD) that function as transcription factors and chromatin modifiers, such as POU3F2 and ZNF804A, and genes coding for cell adhesion proteins implicated in these conditions including NRXN1 and NLGN1. In addition, a number of novel lncRNAs were found to undergo dramatic changes in expression, one of which is HOTAIRM1, a regulator of several HOXA genes during myelopoiesis. The increase we observed in differentiating neurons suggests a role in neurogenesis as well. Finally, several lncRNAs that map near SNPs associated with SZ in genome wide association studies also increase during neuronal differentiation, suggesting that these novel transcripts may be abnormally regulated in a subgroup of patients
The role of ETG modes in JET-ILW pedestals with varying levels of power and fuelling
We present the results of GENE gyrokinetic calculations based on a series of JET-ITER-like-wall (ILW) type I ELMy H-mode discharges operating with similar experimental inputs but at different levels of power and gas fuelling. We show that turbulence due to electron-temperature-gradient (ETGs) modes produces a significant amount of heat flux in four JET-ILW discharges, and, when combined with neoclassical simulations, is able to reproduce the experimental heat flux for the two low gas pulses. The simulations plausibly reproduce the high-gas heat fluxes as well, although power balance analysis is complicated by short ELM cycles. By independently varying the normalised temperature gradients (omega(T)(e)) and normalised density gradients (omega(ne )) around their experimental values, we demonstrate that it is the ratio of these two quantities eta(e) = omega(Te)/omega(ne) that determines the location of the peak in the ETG growth rate and heat flux spectra. The heat flux increases rapidly as eta(e) increases above the experimental point, suggesting that ETGs limit the temperature gradient in these pulses. When quantities are normalised using the minor radius, only increases in omega(Te) produce appreciable increases in the ETG growth rates, as well as the largest increases in turbulent heat flux which follow scalings similar to that of critical balance theory. However, when the heat flux is normalised to the electron gyro-Bohm heat flux using the temperature gradient scale length L-Te, it follows a linear trend in correspondence with previous work by different authors
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