Perturbation with intrabodies reveals that calpain cleavage is required for degradation of huntingtin exon 1.

Directory of Open Access Journals (Sweden)

Amber L Southwell

2011-01-01

Full Text Available Proteolytic processing of mutant huntingtin (mHtt, the protein that causes Huntington's disease (HD, is critical for mHtt toxicity and disease progression. mHtt contains several caspase and calpain cleavage sites that generate N-terminal fragments that are more toxic than full-length mHtt. Further processing is then required for the degradation of these fragments, which in turn, reduces toxicity. This unknown, secondary degradative process represents a promising therapeutic target for HD.We have used intrabodies, intracellularly expressed antibody fragments, to gain insight into the mechanism of mutant huntingtin exon 1 (mHDx-1 clearance. Happ1, an intrabody recognizing the proline-rich region of mHDx-1, reduces the level of soluble mHDx-1 by increasing clearance. While proteasome and macroautophagy inhibitors reduce turnover of mHDx-1, Happ1 is still able to reduce mHDx-1 under these conditions, indicating Happ1-accelerated mHDx-1 clearance does not rely on these processes. In contrast, a calpain inhibitor or an inhibitor of lysosomal pH block Happ1-mediated acceleration of mHDx-1 clearance. These results suggest that mHDx-1 is cleaved by calpain, likely followed by lysosomal degradation and this process regulates the turnover rate of mHDx-1. Sequence analysis identifies amino acid (AA 15 as a potential calpain cleavage site. Calpain cleavage of recombinant mHDx-1 in vitro yields fragments of sizes corresponding to this prediction. Moreover, when the site is blocked by binding of another intrabody, V(L12.3, turnover of soluble mHDx-1 in living cells is blocked.These results indicate that calpain-mediated removal of the 15 N-terminal AAs is required for the degradation of mHDx-1, a finding that may have therapeutic implications.

Expression of Huntingtons disease markers in the cornea of minipig transgenic for the human mutated huntingtin

Czech Academy of Sciences Publication Activity Database

Ardan, Taras; Juhás, Štefan; Motlík, Jan

2013-01-01

Roč. 91, č. 252 (2013), S016-S016 ISSN 1755-375X. [European Association for Vision and Eye Research EVER 2013. 18.09.2013-21.09.2013, Nice] R&D Projects: GA MŠk ED2.1.00/03.0124; GA TA ČR(CZ) TA01011466 Institutional support: RVO:67985904 Keywords : huntingtin Subject RIV: EB - Genetics ; Molecular Biology

Different Forms of Huntingtin in the Most 
Affected Organs; Brain and Testes of Transgenic Minipigs

Czech Academy of Sciences Publication Activity Database

Vidinská, Daniela; Motlík, Jan; Ellederová, Zdeňka

2015-01-01

Roč. 78, Suppl 2 (2015), s. 66-69 ISSN 1210-7859. [Conference on Animal Models for neurodegenerative Disease s /3./. Liblice, 08.11.2015-10.11.2015] R&D Projects: GA MŠk ED2.1.00/03.0124; GA MŠk(CZ) 7F14308 Institutional support: RVO:67985904 Keywords : Huntington´s disease * transgenic minipig model * mutant huntingtin Subject RIV: FH - Neurology Impact factor: 0.209, year: 2015

Impaired heat shock response in cells expressing full-length polyglutamine-expanded huntingtin.

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Sidhartha M Chafekar

Full Text Available The molecular mechanisms by which polyglutamine (polyQ-expanded huntingtin (Htt causes neurodegeneration in Huntington's disease (HD remain unclear. The malfunction of cellular proteostasis has been suggested as central in HD pathogenesis and also as a target of therapeutic interventions for the treatment of HD. We present results that offer a previously unexplored perspective regarding impaired proteostasis in HD. We find that, under non-stress conditions, the proteostatic capacity of cells expressing full length polyQ-expanded Htt is adequate. Yet, under stress conditions, the presence of polyQ-expanded Htt impairs the heat shock response, a key component of cellular proteostasis. This impaired heat shock response results in a reduced capacity to withstand the damage caused by cellular stress. We demonstrate that in cells expressing polyQ-expanded Htt the levels of heat shock transcription factor 1 (HSF1 are reduced, and, as a consequence, these cells have an impaired a heat shock response. Also, we found reduced HSF1 and HSP70 levels in the striata of HD knock-in mice when compared to wild-type mice. Our results suggests that full length, non-aggregated polyQ-expanded Htt blocks the effective induction of the heat shock response under stress conditions and may thus trigger the accumulation of cellular damage during the course of HD pathogenesis.

The role of polyglutamine expansion and protein context in disease-related huntingtin/lipid interactions

Science.gov (United States)

Burke, Kathleen Anne

Huntington's Disease (HD) is a neurodegenerative disorder that is defined by the accumulation of nanoscale aggregates comprised of the huntingtin (htt) protein. Aggregation is directly caused by an expanded polyglutamine (polyQ) domain in htt, leading to a diverse population of aggregate species, such as oligomers, fibrils, and annular aggregates. Furthermore, the length of this polyQ domain is directly related to onset and severity of disease. The first 17 amino acids on the N-terminus (N17) and the polyproline domain on the C-terminal side of the polyQ domain have been shown to further modulate the aggregation process. Additionally, N17 appears to have lipid binding properties as htt interacts with a variety of membrane-containing structures present in cells, such as organelles, and interactions with these membrane surfaces may further modulate htt aggregation. To investigate the interaction between htt exon1 and lipid bilayers, in situ atomic force microscopy (AFM) was used to directly monitor the aggregation of htt exon1 constructs with varying Q-length (35Q, 46Q, 51Q, and myc- 53Q) or synthetic peptides with different polyQ domain flanking sequences (KK-Q35-KK, KK-Q 35-P10-KK, N17-Q35-KK, and N 17-Q35-P10-KK) on supported lipid membranes comprised of total brain lipid extract. The exon1 fragments accumulated on the lipid membranes, causing disruption of the membrane, in a polyQ dependent manner. By adding N-terminal tags to the htt exon1 fragments, the interaction with the lipid bilayer was impeded. The KK-Q35-KK and KK-Q 35-P10-KK peptides had no appreciable interaction with lipid bilayers. Interestingly, polyQ peptides with the N17 flanking sequence interacted with the bilayer. N17-Q35-KK formed discrete aggregates on the bilayer, but there was minimal membrane disruption. The N17-Q35-P10-KK peptide interacted more aggressively with the lipid bilayer in a manner reminiscent of the htt exon1 proteins.

Dysregulation of gene expression in the striatum of BACHD rats expressing full-length mutant huntingtin and associated abnormalities on molecular and protein levels.

Science.gov (United States)

Yu-Taeger, Libo; Bonin, Michael; Stricker-Shaver, Janice; Riess, Olaf; Nguyen, Hoa Huu Phuc

2017-05-01

Huntington disease (HD) is an autosomal dominantly inherited neurodegenerative disorder caused by a CAG repeat expansion in the gene coding for the huntingtin protein (HTT). Mutant HTT (mHTT) has been proposed to cause neuronal dysfunction and neuronal loss through multiple mechanisms. Transcriptional changes may be a core pathogenic feature of HD. Utilizing the Affymetrix platform we performed a genome-wide RNA expression analysis in two BACHD transgenic rat lines (TG5 and TG9) at 12 months of age, both of which carry full-length human mHTT but with different expression levels. By defining the threshold of significance at p < 0.01, we found 1608 genes and 871 genes differentially expressed in both TG5 and TG9 rats when compared to the wild type littermates, respectively. We only chose the highly up-/down-regulated genes for further analysis by setting an additional threshold of 1.5 fold change. Comparing gene expression profiles of human HD brains and BACHD rats revealed a high concordance in both functional and IPA (Ingenuity Pathway Analysis) canonical pathways relevant to HD. In addition, we investigated the causes leading to gene expression changes at molecular and protein levels in BACHD rats including the involvement of polyQ-containing transcription factors TATA box-binding protein (TBP), Sp1 and CBP as well as the chromatin structure. We demonstrate that the BACHD rat model recapitulates the gene expression changes of the human disease supporting its role as a preclinical research animal model. We also show for the first time that TFIID complex formation is reduced, while soluble TBP is increased in an HD model. This finding suggests that mHTT is a competitor instead of a recruiter of polyQ-containing transcription factors in the transcription process in HD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Systematic analysis of fly models with multiple drivers reveals different effects of ataxin-1 and huntingtin in neuron subtype-specific expression.

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Risa Shiraishi

Full Text Available The fruit fly, Drosophila melanogaster, is a commonly used model organism for neurodegenerative diseases. Its major advantages include a short lifespan and its susceptibility to manipulation using sophisticated genetic techniques. Here, we report the systematic comparison of fly models of two polyglutamine (polyQ diseases. We induced expression of the normal and mutant forms of full-length Ataxin-1 and Huntingtin exon 1 in cholinergic, dopaminergic, and motor neurons, and glial cells using cell type-specific drivers. We systematically analyzed their effects based on multiple phenotypes: eclosion rate, lifespan, motor performance, and circadian rhythms of spontaneous activity. This systematic assay system enabled us to quantitatively evaluate and compare the functional disabilities of different genotypes. The results suggest different effects of Ataxin-1 and Huntingtin on specific types of neural cells during development and in adulthood. In addition, we confirmed the therapeutic effects of LiCl and butyrate using representative models. These results support the usefulness of this assay system for screening candidate chemical compounds that modify the pathologies of polyQ diseases.

Msh2 acts in medium-spiny striatal neurons as an enhancer of CAG instability and mutant huntingtin phenotypes in Huntington's disease knock-in mice.

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Marina Kovalenko

Full Text Available The CAG trinucleotide repeat mutation in the Huntington's disease gene (HTT exhibits age-dependent tissue-specific expansion that correlates with disease onset in patients, implicating somatic expansion as a disease modifier and potential therapeutic target. Somatic HTT CAG expansion is critically dependent on proteins in the mismatch repair (MMR pathway. To gain further insight into mechanisms of somatic expansion and the relationship of somatic expansion to the disease process in selectively vulnerable MSNs we have crossed HTT CAG knock-in mice (HdhQ111 with mice carrying a conditional (floxed Msh2 allele and D9-Cre transgenic mice, in which Cre recombinase is expressed specifically in MSNs within the striatum. Deletion of Msh2 in MSNs eliminated Msh2 protein in those neurons. We demonstrate that MSN-specific deletion of Msh2 was sufficient to eliminate the vast majority of striatal HTT CAG expansions in HdhQ111 mice. Furthermore, MSN-specific deletion of Msh2 modified two mutant huntingtin phenotypes: the early nuclear localization of diffusely immunostaining mutant huntingtin was slowed; and the later development of intranuclear huntingtin inclusions was dramatically inhibited. Therefore, Msh2 acts within MSNs as a genetic enhancer both of somatic HTT CAG expansions and of HTT CAG-dependent phenotypes in mice. These data suggest that the selective vulnerability of MSNs may be at least in part contributed by the propensity for somatic expansion in these neurons, and imply that intervening in the expansion process is likely to have therapeutic benefit.

Assembly of Huntingtin headpiece into α-helical bundles.

Science.gov (United States)

Ozgur, Beytullah; Sayar, Mehmet

2017-05-24

Protein aggregation is a hallmark of neurodegenerative disorders. In this group of brain-related disorders, a disease-specific "host" protein or fragment misfolds and adopts a metastatic, aggregate-prone conformation. Often, this misfolded conformation is structurally and thermodynamically different from its native state. Intermolecular contacts, which arise in this non-native state, promote aggregation. In this regard, understanding the molecular principles and mechanisms that lead to the formation of such a non-native state and further promote the formation of the critical nucleus for fiber growth is essential. In this study, the authors analyze the aggregation propensity of Huntingtin headpiece (htt NT ), which is known to facilitate the polyQ aggregation, in relation to the helix mediated aggregation mechanism proposed by the Wetzel group. The authors demonstrate that even though htt NT displays a degenerate conformational spectrum on its own, interfaces of macroscopic or molecular origin can promote the α-helix conformation, eliminating all other alternatives in the conformational phase space. Our findings indicate that htt NT molecules do not have a strong orientational preference for parallel or antiparallel orientation of the helices within the aggregate. However, a parallel packed bundle of helices would support the idea of increased polyglutamine concentration, to pave the way for cross-β structures.

Positive lysosomal modulation as a unique strategy to treat age-related protein accumulation diseases.

Science.gov (United States)

Bahr, Ben A; Wisniewski, Meagan L; Butler, David

2012-04-01

Lysosomes are involved in degrading and recycling cellular ingredients, and their disruption with age may contribute to amyloidogenesis, paired helical filaments (PHFs), and α-synuclein and mutant huntingtin aggregation. Lysosomal cathepsins are upregulated by accumulating proteins and more so by the modulator Z-Phe-Ala-diazomethylketone (PADK). Such positive modulators of the lysosomal system have been studied in the well-characterized hippocampal slice model of protein accumulation that exhibits the pathogenic cascade of tau aggregation, tubulin breakdown, microtubule destabilization, transport failure, and synaptic decline. Active cathepsins were upregulated by PADK; Rab proteins were modified as well, indicating enhanced trafficking, whereas lysosome-associated membrane protein and proteasome markers were unchanged. Lysosomal modulation reduced the pre-existing PHF deposits, restored tubulin structure and transport, and recovered synaptic components. Further proof-of-principle studies used Alzheimer disease mouse models. It was recently reported that systemic PADK administration caused dramatic increases in cathepsin B protein and activity levels, whereas neprilysin, insulin-degrading enzyme, α-secretase, and β-secretase were unaffected by PADK. In the transgenic models, PADK treatment resulted in clearance of intracellular amyloid beta (Aβ) peptide and concomitant reduction of extracellular deposits. Production of the less pathogenic Aβ(1-38) peptide corresponded with decreased levels of Aβ(1-42), supporting the lysosome's antiamyloidogenic role through intracellular truncation. Amelioration of synaptic and behavioral deficits also indicates a neuroprotective function of the lysosomal system, identifying lysosomal modulation as an avenue for disease-modifying therapies. From the in vitro and in vivo findings, unique lysosomal modulators represent a minimally invasive, pharmacologically controlled strategy against protein accumulation disorders to enhance

Huntingtin-associated protein-1 (HAP1) regulates endocytosis and interacts with multiple trafficking-related proteins.

Science.gov (United States)

Mackenzie, Kimberly D; Lim, Yoon; Duffield, Michael D; Chataway, Timothy; Zhou, Xin-Fu; Keating, Damien J

2017-07-01

Huntingtin-associated protein 1 (HAP1) was initially identified as a binding partner of huntingtin, mutations in which underlie Huntington's disease. Subcellular localization and protein interaction data indicate that HAP1 may be important in vesicle trafficking, cell signalling and receptor internalization. In this study, a proteomics approach was used for the identification of novel HAP1-interacting partners to attempt to shed light on the physiological function of HAP1. Using affinity chromatography with HAP1-GST protein fragments bound to Sepharose columns, this study identified a number of trafficking-related proteins that bind to HAP1. Interestingly, many of the proteins that were identified by mass spectrometry have trafficking-related functions and include the clathrin light chain B and Sec23A, an ER to Golgi trafficking vesicle coat component. Using co-immunoprecipitation and GST-binding assays the association between HAP1 and clathrin light chain B has been validated in vitro. This study also finds that HAP1 co-localizes with clathrin light chain B. In line with a physiological function of the HAP1-clathrin interaction this study detected a dramatic reduction in vesicle retrieval and endocytosis in adrenal chromaffin cells. Furthermore, through examination of transferrin endocytosis in HAP1 -/- cortical neurons, this study has determined that HAP1 regulates neuronal endocytosis. In this study, the interaction between HAP1 and Sec23A was also validated through endogenous co-immunoprecipitation in rat brain homogenate. Through the identification of novel HAP1 binding partners, many of which have putative trafficking roles, this study provides us with new insights into the mechanisms underlying the important physiological function of HAP1 as an intracellular trafficking protein through its protein-protein interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

Modulating the level of components within plants

Science.gov (United States)

Bobzin, Steven Craig; Apuya, Nestor; Chiang, Karen; Doukhanina, Elena; Feldmann, Kenneth; Jankowski, Boris; Margolles-Clark, Emilio; Mumenthaler, Daniel; Okamuro, Jack; Park, Joon-Hyun; Van Fleet, Jennifer E.; Zhang, Ke

2017-09-12

Materials and Methods for identifying lignin regulatory region-regulatory protein associations are disclosed. Materials and methods for modulating lignin accumulation are also disclosed. In addition, methods and materials for modulating (e.g., increasing or decreasing) the level of a component (e.g., protein, oil, lignin, carbon, a carotenoid, or a triterpenoid) in plants are disclosed.

A design of optical modulation system with pixel-level modulation accuracy

Science.gov (United States)

Zheng, Shiwei; Qu, Xinghua; Feng, Wei; Liang, Baoqiu

2018-01-01

Vision measurement has been widely used in the field of dimensional measurement and surface metrology. However, traditional methods of vision measurement have many limits such as low dynamic range and poor reconfigurability. The optical modulation system before image formation has the advantage of high dynamic range, high accuracy and more flexibility, and the modulation accuracy is the key parameter which determines the accuracy and effectiveness of optical modulation system. In this paper, an optical modulation system with pixel level accuracy is designed and built based on multi-points reflective imaging theory and digital micromirror device (DMD). The system consisted of digital micromirror device, CCD camera and lens. Firstly we achieved accurate pixel-to-pixel correspondence between the DMD mirrors and the CCD pixels by moire fringe and an image processing of sampling and interpolation. Then we built three coordinate systems and calculated the mathematic relationship between the coordinate of digital micro-mirror and CCD pixels using a checkerboard pattern. A verification experiment proves that the correspondence error is less than 0.5 pixel. The results show that the modulation accuracy of system meets the requirements of modulation. Furthermore, the high reflecting edge of a metal circular piece can be detected using the system, which proves the effectiveness of the optical modulation system.

The Circuit-Level Decoupling Modulation Strategy for Three-Level Neutral-Point-Clamped (TL-NPC) Inverter

DEFF Research Database (Denmark)

Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.

2011-01-01

In this paper, a circuit-level decoupling modulation strategy is proposed for the three-level (TL) neutral-point-clamped (NPC) inverters. With the proposed modulation scheme, the TL-NPC inverter can be decoupled into two three-level Buck converters in each defined operating section, which makes...

On decoding of multi-level MPSK modulation codes

Science.gov (United States)

Lin, Shu; Gupta, Alok Kumar

1990-01-01

The decoding problem of multi-level block modulation codes is investigated. The hardware design of soft-decision Viterbi decoder for some short length 8-PSK block modulation codes is presented. An effective way to reduce the hardware complexity of the decoder by reducing the branch metric and path metric, using a non-uniform floating-point to integer mapping scheme, is proposed and discussed. The simulation results of the design are presented. The multi-stage decoding (MSD) of multi-level modulation codes is also investigated. The cases of soft-decision and hard-decision MSD are considered and their performance are evaluated for several codes of different lengths and different minimum squared Euclidean distances. It is shown that the soft-decision MSD reduces the decoding complexity drastically and it is suboptimum. The hard-decision MSD further simplifies the decoding while still maintaining a reasonable coding gain over the uncoded system, if the component codes are chosen properly. Finally, some basic 3-level 8-PSK modulation codes using BCH codes as component codes are constructed and their coding gains are found for hard decision multistage decoding.

Multi-stage decoding of multi-level modulation codes

Science.gov (United States)

Lin, Shu; Kasami, Tadao; Costello, Daniel J., Jr.

1991-01-01

Various types of multi-stage decoding for multi-level modulation codes are investigated. It is shown that if the component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. Particularly, it is shown that the difference in performance between the suboptimum multi-stage soft-decision maximum likelihood decoding of a modulation code and the single-stage optimum soft-decision decoding of the code is very small, only a fraction of dB loss in signal to noise ratio at a bit error rate (BER) of 10(exp -6).

Reproductive parameters and mitochondrial function in spermatozoa of F1 and F2 minipig boars transgenic for n-terminal part of the human mutated huntingtin

Czech Academy of Sciences Publication Activity Database

Mačáková, Monika; Hansíková, H.; Pavlok, Antonín; Hajková, Z.; Sádková, J.; Juhás, Štefan; Juhásová, Jana; Baxa, Monika; Zeman, J.; Motlík, Jan

2012-01-01

Roč. 83, Suppl 1 (2012), A16-A16 ISSN 0022-3050. [European Huntington´s disease network 2012 plenary meeting. 14.09.2012-16.09.2012, Stockholm] R&D Projects: GA TA ČR TA01011466 Institutional support: RVO:67985904 Keywords : huntingtin Subject RIV: EB - Genetics ; Molecular Biology

Mass spektrometry-based SRM assay for quantification of human mutant huntingtin protein in a transgenic minipig model of Huntington´s disease

Czech Academy of Sciences Publication Activity Database

Kotrčová, Eva; Suchá, Rita; Tylečková, Jiřina; Dresler, J.; Kovářová, Hana

2015-01-01

Roč. 78, Suppl 2 (2015), s. 17-17 ISSN 1210-7859. [Conference on Animal Models for neurodegenerative Diseases /3./. 08.11.2015-10.11.2015, Liblice] R&D Projects: GA TA ČR(CZ) TA01011466; GA MŠk ED2.1.00/03.0124; GA MŠk(CZ) 7F14308 Institutional support: RVO:67985904 Keywords : huntingtin gene Subject RIV: FH - Neurology

Preventing mutant huntingtin proteolysis and intermittent fasting promote autophagy in models of Huntington disease.

Science.gov (United States)

Ehrnhoefer, Dagmar E; Martin, Dale D O; Schmidt, Mandi E; Qiu, Xiaofan; Ladha, Safia; Caron, Nicholas S; Skotte, Niels H; Nguyen, Yen T N; Vaid, Kuljeet; Southwell, Amber L; Engemann, Sabine; Franciosi, Sonia; Hayden, Michael R

2018-03-06

Huntington disease (HD) is caused by the expression of mutant huntingtin (mHTT) bearing a polyglutamine expansion. In HD, mHTT accumulation is accompanied by a dysfunction in basal autophagy, which manifests as specific defects in cargo loading during selective autophagy. Here we show that the expression of mHTT resistant to proteolysis at the caspase cleavage site D586 (C6R mHTT) increases autophagy, which may be due to its increased binding to the autophagy adapter p62. This is accompanied by faster degradation of C6R mHTT in vitro and a lack of mHTT accumulation the C6R mouse model with age. These findings may explain the previously observed neuroprotective properties of C6R mHTT. As the C6R mutation cannot be easily translated into a therapeutic approach, we show that a scheduled feeding paradigm is sufficient to lower mHTT levels in YAC128 mice expressing cleavable mHTT. This is consistent with a previous model, where the presence of cleavable mHTT impairs basal autophagy, while fasting-induced autophagy remains functional. In HD, mHTT clearance and autophagy may become increasingly impaired as a function of age and disease stage, because of gradually increased activity of mHTT-processing enzymes. Our findings imply that mHTT clearance could be enhanced by a regulated dietary schedule that promotes autophagy.

Analysis of Harmonic Injection to the Modulation of Multi-Level ...

African Journals Online (AJOL)

This paper explores the analysis of third and ninth harmonic injection to the modulation of a multilevel diode clamped converter (DCC) at a varying modulation index. The spectral distributions of the various multi-level waveforms obtained under normal modulation index of 0.8 and over modulation index of 1.15 were ...

Binaural processing of modulated interaural level differences

DEFF Research Database (Denmark)

Thompson, Eric Robert; Dau, Torsten

2008-01-01

Two experiments are presented that measure the acuity of binaural processing of modulated interaural level differences ILDs using psychoacoustic methods. In both experiments, dynamic ILDs were created by imposing an interaurally antiphasic sinusoidal amplitude modulation AM signal on high...... frequency, broadly tuned, bandpass-shaped patterns were obtained. Simulations with an existing binaural model show that a low-pass filter to limit the binaural temporal resolution is not sufficient to predict the results of the experiments....

Multi-level trellis coded modulation and multi-stage decoding

Science.gov (United States)

Costello, Daniel J., Jr.; Wu, Jiantian; Lin, Shu

1990-01-01

Several constructions for multi-level trellis codes are presented and many codes with better performance than previously known codes are found. These codes provide a flexible trade-off between coding gain, decoding complexity, and decoding delay. New multi-level trellis coded modulation schemes using generalized set partitioning methods are developed for Quadrature Amplitude Modulation (QAM) and Phase Shift Keying (PSK) signal sets. New rotationally invariant multi-level trellis codes which can be combined with differential encoding to resolve phase ambiguity are presented.

Hydrophobically Modified siRNAs Silence Huntingtin mRNA in Primary Neurons and Mouse Brain

Directory of Open Access Journals (Sweden)

Julia F Alterman

2015-01-01

Full Text Available Applications of RNA interference for neuroscience research have been limited by a lack of simple and efficient methods to deliver oligonucleotides to primary neurons in culture and to the brain. Here, we show that primary neurons rapidly internalize hydrophobically modified siRNAs (hsiRNAs added directly to the culture medium without lipid formulation. We identify functional hsiRNAs targeting the mRNA of huntingtin, the mutation of which is responsible for Huntington's disease, and show that direct uptake in neurons induces potent and specific silencing in vitro. Moreover, a single injection of unformulated hsiRNA into mouse brain silences Htt mRNA with minimal neuronal toxicity. Thus, hsiRNAs embody a class of therapeutic oligonucleotides that enable simple and straightforward functional studies of genes involved in neuronal biology and neurodegenerative disorders in a native biological context.

Multi-stage decoding for multi-level block modulation codes

Science.gov (United States)

Lin, Shu

1991-01-01

In this paper, we investigate various types of multi-stage decoding for multi-level block modulation codes, in which the decoding of a component code at each stage can be either soft-decision or hard-decision, maximum likelihood or bounded-distance. Error performance of codes is analyzed for a memoryless additive channel based on various types of multi-stage decoding, and upper bounds on the probability of an incorrect decoding are derived. Based on our study and computation results, we find that, if component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. In particular, we find that the difference in performance between the suboptimum multi-stage soft-decision maximum likelihood decoding of a modulation code and the single-stage optimum decoding of the overall code is very small: only a fraction of dB loss in SNR at the probability of an incorrect decoding for a block of 10(exp -6). Multi-stage decoding of multi-level modulation codes really offers a way to achieve the best of three worlds, bandwidth efficiency, coding gain, and decoding complexity.

Space Vector Pulse Width Modulation of a Multi-Level Diode ...

African Journals Online (AJOL)

Space Vector Pulse Width Modulation of a Multi-Level Diode Clamped ... of MATLAB /SIMULINK modeling of the space vector pulse-width modulation and the ... two adjacent active vectors in determining the switching process of the multilevel ...

Ser46 phosphorylation and prolyl-isomerase Pin1-mediated isomerization of p53 are key events in p53-dependent apoptosis induced by mutant huntingtin.

Science.gov (United States)

Grison, Alice; Mantovani, Fiamma; Comel, Anna; Agostoni, Elena; Gustincich, Stefano; Persichetti, Francesca; Del Sal, Giannino

2011-11-01

Huntington disease (HD) is a neurodegenerative disorder caused by a CAG repeat expansion in the gene coding for huntingtin protein. Several mechanisms have been proposed by which mutant huntingtin (mHtt) may trigger striatal neurodegeneration, including mitochondrial dysfunction, oxidative stress, and apoptosis. Furthermore, mHtt induces DNA damage and activates a stress response. In this context, p53 plays a crucial role in mediating mHtt toxic effects. Here we have dissected the pathway of p53 activation by mHtt in human neuronal cells and in HD mice, with the aim of highlighting critical nodes that may be pharmacologically manipulated for therapeutic intervention. We demonstrate that expression of mHtt causes increased phosphorylation of p53 on Ser46, leading to its interaction with phosphorylation-dependent prolyl isomerase Pin1 and consequent dissociation from the apoptosis inhibitor iASPP, thereby inducing the expression of apoptotic target genes. Inhibition of Ser46 phosphorylation by targeting homeodomain-interacting protein kinase 2 (HIPK2), PKCδ, or ataxia telangiectasia mutated kinase, as well as inhibition of the prolyl isomerase Pin1, prevents mHtt-dependent apoptosis of neuronal cells. These results provide a rationale for the use of small-molecule inhibitors of stress-responsive protein kinases and Pin1 as a potential therapeutic strategy for HD treatment.

Length and sequence dependence in the association of Huntingtin protein with lipid membranes

Science.gov (United States)

Jawahery, Sudi; Nagarajan, Anu; Matysiak, Silvina

2013-03-01

There is a fundamental gap in our understanding of how aggregates of mutant Huntingtin protein (htt) with overextended polyglutamine (polyQ) sequences gain the toxic properties that cause Huntington's disease (HD). Experimental studies have shown that the most important step associated with toxicity is the binding of mutant htt aggregates to lipid membranes. Studies have also shown that flanking amino acid sequences around the polyQ sequence directly affect interactions with the lipid bilayer, and that polyQ sequences of greater than 35 glutamine repeats in htt are a characteristic of HD. The key steps that determine how flanking sequences and polyQ length affect the structure of lipid bilayers remain unknown. In this study, we use atomistic molecular dynamics simulations to study the interactions between lipid membranes of varying compositions and polyQ peptides of varying lengths and flanking sequences. We find that overextended polyQ interactions do cause deformation in model membranes, and that the flanking sequences do play a role in intensifying this deformation by altering the shape of the affected regions.

Cells exposed to a huntingtin fragment containing an expanded polyglutamine tract show no sign of ion channel formation: results arguing against the ion channel hypothesis

DEFF Research Database (Denmark)

Nørremølle, Anne; Grunnet, Morten; Hasholt, Lis

2003-01-01

Ion channels formed by expanded polyglutamine tracts have been proposed to play an important role in the pathological processes leading to neurodegeneration in Huntington's disease and other CAG repeat diseases. We tested the capacity of a huntingtin fragment containing an expanded polyglutamine...... in the currents recorded in any of the two expression systems, indicating no changes in ion channel activity. The results therefore argue against the proposed hypothesis of expanded polyglutamines forming ion channels....

The Kynurenine Pathway Modulates Neurodegeneration in a Drosophila Model of Huntington’s Disease

Science.gov (United States)

Campesan, Susanna; Green, Edward W.; Breda, Carlo; Sathyasaikumar, Korrapati V.; Muchowski, Paul J.; Schwarcz, Robert; Kyriacou, Charalambos P.; Giorgini, Flaviano

2014-01-01

Summary Neuroactive metabolites of the kynurenine pathway (KP) of tryptophan degradation have been implicated in the pathophysiology of neurodegenerative disorders, including Huntington’s disease (HD) [1]. A central hallmark of HD is neurodegeneration caused by a polyglutamine expansion in the huntingtin (htt) protein [2]. Here we exploit a transgenic Drosophila melanogaster model of HD to interrogate the therapeutic potential of KP manipulation. We observe that genetic and pharmacological inhibition of kynurenine 3-monooxygenase (KMO) increases levels of the neuroprotective metabolite kynurenic acid (KYNA) relative to the neurotoxic metabolite 3-hydroxykynurenine (3-HK) and ameliorates neurodegeneration. We also find that genetic inhibition of tryptophan 2,3-dioxygenase (TDO), the first and rate-limiting step in the pathway, leads to a similar neuroprotective shift toward KYNA synthesis. Importantly, we demonstrate that the feeding of KYNA and 3-HK to HD model flies directly modulates neurodegeneration, underscoring the causative nature of these metabolites. This study provides the first genetic evidence that inhibition of KMO and TDO activity protects against neurodegenerative disease in an animal model, indicating that strategies targeted at two key points within the KP may have therapeutic relevance in HD, and possibly other neurodegenerative disorders. PMID:21636279

Huntingtin coordinates the dynein-mediated dynamic positioning of endosomes and lysosomes

Science.gov (United States)

Caviston, Juliane P.; Zajac, Allison L.; Tokito, Mariko; Holzbaur, Erika L.F.

2011-01-01

Huntingtin (Htt) is a membrane-associated scaffolding protein that interacts with microtubule motors as well as actin-associated adaptor molecules. We examined a role for Htt in the dynein-mediated intracellular trafficking of endosomes and lysosomes. In HeLa cells depleted of either Htt or dynein, early, recycling, and late endosomes (LE)/lysosomes all become dispersed. Despite altered organelle localization, kinetic assays indicate only minor defects in intracellular trafficking. Expression of full-length Htt is required to restore organelle localization in Htt-depleted cells, supporting a role for Htt as a scaffold that promotes functional interactions along its length. In dynein-depleted cells, LE/lysosomes accumulate in tight patches near the cortex, apparently enmeshed by cortactin-positive actin filaments; Latrunculin B-treatment disperses these patches. Peripheral LE/lysosomes in dynein-depleted cells no longer colocalize with microtubules. Htt may be required for this off-loading, as the loss of microtubule association is not seen in Htt-depleted cells or in cells depleted of both dynein and Htt. Inhibition of kinesin-1 relocalizes peripheral LE/lysosomes induced by Htt depletion but not by dynein depletion, consistent with their detachment from microtubules upon dynein knockdown. Together, these data support a model of Htt as a facilitator of dynein-mediated trafficking that may regulate the cytoskeletal association of dynamic organelles. PMID:21169558

Sequestration of Sup35 by aggregates of huntingtin fragments causes toxicity of [PSI+] yeast.

Science.gov (United States)

Zhao, Xiaohong; Park, Yang-Nim; Todor, Horia; Moomau, Christine; Masison, Daniel; Eisenberg, Evan; Greene, Lois E

2012-07-06

Expression of huntingtin fragments with 103 glutamines (HttQ103) is toxic in yeast containing either the [PIN(+)] prion, which is the amyloid form of Rnq1, or [PSI(+)] prion, which is the amyloid form of Sup35. We find that HttQP103, which has a polyproline region at the C-terminal end of the polyQ repeat region, is significantly more toxic in [PSI(+)] yeast than in [PIN(+)], even though HttQP103 formed multiple aggregates in both [PSI(+)] and [PIN(+)] yeast. This toxicity was only observed in the strong [PSI(+)] variant, not the weak [PSI(+)] variant, which has more soluble Sup35 present than the strong variant. Furthermore, expression of the MC domains of Sup35, which retains the C-terminal domain of Sup35, but lacks the N-terminal prion domain, almost completely rescued HttQP103 toxicity, but was less effective in rescuing HttQ103 toxicity. Therefore, the toxicity of HttQP103 in yeast containing the [PSI(+)] prion is primarily due to sequestration of the essential protein, Sup35.

Understanding of phase modulation in two-level systems through inverse scattering

International Nuclear Information System (INIS)

Hasenfeld, A.; Hammes, S.L.; Warren, W.S.

1988-01-01

Analytical and numerical calculations describe the effects of shaped radiation pulses on two-level systems in terms of quantum-mechanical scattering. Previous results obtained in the reduced case of amplitude modulation are extended to the general case of simultaneous amplitude and phase modulation. We show that an infinite family of phase- and amplitude-modulated pulses all generate rectangular inversion profiles. Experimental measurements also verify the theoretical analysis

Analysis of proteolytic processes and enzymatic activities in the generation of huntingtin n-terminal fragments in an HEK293 cell model.

Directory of Open Access Journals (Sweden)

Andrew T N Tebbenkamp

Full Text Available N-terminal fragments of mutant huntingtin (htt that terminate between residues 90-115, termed cleavage product A or 1 (cp-A/1, form intracellular and intranuclear inclusion bodies in the brains of patients with Huntington's disease (HD. These fragments appear to be proteolytic products of the full-length protein. Here, we use an HEK293 cell culture model to investigate huntingtin proteolytic processing; previous studies of these cells have demonstrated cleavage of htt to cp-A/1 like htt fragments.Recombinant N-terminal htt fragments, terminating at residue 171 (also referred to as cp-B/2 like, were efficiently cleaved to produce cp-A/1 whereas fragments representing endogenous caspase, calpain, and metalloproteinase cleavage products, terminating between residues 400-600, were inefficiently cleaved. Using cysteine-labeling techniques and antibody binding mapping, we localized the C-terminus of the cp-A/1 fragments produced by HEK293 cells to sequences minimally limited by cysteine 105 and an antibody epitope composed of residues 115-124. A combination of genetic and pharmacologic approaches to inhibit potential proteases, including γ-secretase and calpain, proved ineffective in preventing production of cp-A/1.Our findings indicate that HEK293 cells express a protease that is capable of efficiently cleaving cp-B/2 like fragments of htt with normal or expanded glutamine repeats. For reasons that remain unclear, this protease cleaves longer htt fragments, with normal or expanded glutamine expansions, much less efficiently. The protease in HEK293 cells that is capable of generating a cp-A/1 like htt fragment may be a novel protease with a high preference for a cp-B/2-like htt fragment as substrate.

Environmental factors as modulators of neurodegeneration: insights from gene-environment interactions in Huntington's disease.

Science.gov (United States)

Mo, Christina; Hannan, Anthony J; Renoir, Thibault

2015-05-01

Unlike many other neurodegenerative diseases with established gene-environment interactions, Huntington's disease (HD) is viewed as a disorder governed by genetics. The cause of the disease is a highly penetrant tandem repeat expansion encoding an extended polyglutamine tract in the huntingtin protein. In the year 2000, a pioneering study showed that the disease could be delayed in transgenic mice by enriched housing conditions. This review describes subsequent human and preclinical studies identifying environmental modulation of motor, cognitive, affective and other symptoms found in HD. Alongside the behavioral observations we also discuss potential mechanisms and the relevance to other neurodegenerative disorders, including Alzheimer's and Parkinson's disease. In mouse models of HD, increased sensorimotor and cognitive stimulation can delay or ameliorate various endophenotypes. Potential mechanisms include increased trophic support, synaptic plasticity, adult neurogenesis, and other forms of experience-dependent cellular plasticity. Subsequent clinical investigations support a role for lifetime activity levels in modulating the onset and progression of HD. Stress can accelerate memory and olfactory deficits and exacerbate cellular dysfunctions in HD mice. In the absence of effective treatments to slow the course of HD, environmental interventions offer feasible approaches to delay the disease, however further preclinical and human studies are needed in order to generate clinical recommendations. Environmental interventions could be combined with future pharmacological therapies and stimulate the identification of enviromimetics, drugs which mimic or enhance the beneficial effects of cognitive stimulation and physical activity. Copyright © 2015. Published by Elsevier Ltd.

TF.Learn: TensorFlow's High-level Module for Distributed Machine Learning

OpenAIRE

Tang, Yuan

2016-01-01

TF.Learn is a high-level Python module for distributed machine learning inside TensorFlow. It provides an easy-to-use Scikit-learn style interface to simplify the process of creating, configuring, training, evaluating, and experimenting a machine learning model. TF.Learn integrates a wide range of state-of-art machine learning algorithms built on top of TensorFlow's low level APIs for small to large-scale supervised and unsupervised problems. This module focuses on bringing machine learning t...

The front-end (Level-0) electronics interface module for the LHCb RICH detectors

Energy Technology Data Exchange (ETDEWEB)

Adinolfi, M. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Bibby, J.H. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Brisbane, S. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Gibson, V. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Harnew, N. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Jones, M. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Libby, J. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)]. E-mail: j.libby1@physics.ox.ac.uk; Powell, A. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Newby, C. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Rotolo, N. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Smale, N. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Somerville, L.; Sullivan, P.; Topp-Jorgensen, S. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Wotton, S. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Wyllie, K. [CERN, CH-1211, Geneva 23 (Switzerland)

2007-03-11

The front-end (Level-0) electronics interface module for the LHCb Ring Imaging Cherenkov (RICH) detectors is described. This module integrates the novel hybrid photon detectors (HPDs), which instrument the RICH detectors, to the LHCb trigger, data acquisition (DAQ) and control systems. The system operates at 40 MHz with a first-level trigger rate of 1 MHz. The module design is presented and results are given for both laboratory and beam tests.

The front-end (Level-0) electronics interface module for the LHCb RICH detectors

International Nuclear Information System (INIS)

Adinolfi, M.; Bibby, J.H.; Brisbane, S.; Gibson, V.; Harnew, N.; Jones, M.; Libby, J.; Powell, A.; Newby, C.; Rotolo, N.; Smale, N.; Somerville, L.; Sullivan, P.; Topp-Jorgensen, S.; Wotton, S.; Wyllie, K.

2007-01-01

The front-end (Level-0) electronics interface module for the LHCb Ring Imaging Cherenkov (RICH) detectors is described. This module integrates the novel hybrid photon detectors (HPDs), which instrument the RICH detectors, to the LHCb trigger, data acquisition (DAQ) and control systems. The system operates at 40 MHz with a first-level trigger rate of 1 MHz. The module design is presented and results are given for both laboratory and beam tests

HD CAG-correlated gene expression changes support a simple dominant gain of function

Science.gov (United States)

Jacobsen, Jessie C.; Gregory, Gillian C.; Woda, Juliana M.; Thompson, Morgan N.; Coser, Kathryn R.; Murthy, Vidya; Kohane, Isaac S.; Gusella, James F.; Seong, Ihn Sik; MacDonald, Marcy E.; Shioda, Toshi; Lee, Jong-Min

2011-01-01

Huntington's disease is initiated by the expression of a CAG repeat-encoded polyglutamine region in full-length huntingtin, with dominant effects that vary continuously with CAG size. The mechanism could involve a simple gain of function or a more complex gain of function coupled to a loss of function (e.g. dominant negative-graded loss of function). To distinguish these alternatives, we compared genome-wide gene expression changes correlated with CAG size across an allelic series of heterozygous CAG knock-in mouse embryonic stem (ES) cell lines (HdhQ20/7, HdhQ50/7, HdhQ91/7, HdhQ111/7), to genes differentially expressed between Hdhex4/5/ex4/5 huntingtin null and wild-type (HdhQ7/7) parental ES cells. The set of 73 genes whose expression varied continuously with CAG length had minimal overlap with the 754-member huntingtin-null gene set but the two were not completely unconnected. Rather, the 172 CAG length-correlated pathways and 238 huntingtin-null significant pathways clustered into 13 shared categories at the network level. A closer examination of the energy metabolism and the lipid/sterol/lipoprotein metabolism categories revealed that CAG length-correlated genes and huntingtin-null-altered genes either were different members of the same pathways or were in unique, but interconnected pathways. Thus, varying the polyglutamine size in full-length huntingtin produced gene expression changes that were distinct from, but related to, the effects of lack of huntingtin. These findings support a simple gain-of-function mechanism acting through a property of the full-length huntingtin protein and point to CAG-correlative approaches to discover its effects. Moreover, for therapeutic strategies based on huntingtin suppression, our data highlight processes that may be more sensitive to the disease trigger than to decreased huntingtin levels. PMID:21536587

Huntingtin interacting proteins are genetic modifiers of neurodegeneration.

Directory of Open Access Journals (Sweden)

Linda S Kaltenbach

2007-05-01

Full Text Available Huntington's disease (HD is a fatal neurodegenerative condition caused by expansion of the polyglutamine tract in the huntingtin (Htt protein. Neuronal toxicity in HD is thought to be, at least in part, a consequence of protein interactions involving mutant Htt. We therefore hypothesized that genetic modifiers of HD neurodegeneration should be enriched among Htt protein interactors. To test this idea, we identified a comprehensive set of Htt interactors using two complementary approaches: high-throughput yeast two-hybrid screening and affinity pull down followed by mass spectrometry. This effort led to the identification of 234 high-confidence Htt-associated proteins, 104 of which were found with the yeast method and 130 with the pull downs. We then tested an arbitrary set of 60 genes encoding interacting proteins for their ability to behave as genetic modifiers of neurodegeneration in a Drosophila model of HD. This high-content validation assay showed that 27 of 60 orthologs tested were high-confidence genetic modifiers, as modification was observed with more than one allele. The 45% hit rate for genetic modifiers seen among the interactors is an order of magnitude higher than the 1%-4% typically observed in unbiased genetic screens. Genetic modifiers were similarly represented among proteins discovered using yeast two-hybrid and pull-down/mass spectrometry methods, supporting the notion that these complementary technologies are equally useful in identifying biologically relevant proteins. Interacting proteins confirmed as modifiers of the neurodegeneration phenotype represent a diverse array of biological functions, including synaptic transmission, cytoskeletal organization, signal transduction, and transcription. Among the modifiers were 17 loss-of-function suppressors of neurodegeneration, which can be considered potential targets for therapeutic intervention. Finally, we show that seven interacting proteins from among 11 tested were able to

Generation of induced pluripotent stem cells from transgenic minipigs expressing the N-terminal part of the human mutant huntingtin - a new way to study pathogenesis of Huntington´s disease

Czech Academy of Sciences Publication Activity Database

Lišková, Irena; Vodička, P.; Juhás, Štefan; Klempíř, J.; Motlík, Jan

2015-01-01

Roč. 78, Suppl 2 (2015), s. 18-19 ISSN 1210-7859. [Conference on Animal Models for neurodegenerative Diseases /3./. 08.11.2015-10.11.2015, Liblice] R&D Projects: GA MŠk ED2.1.00/03.0124; GA MŠk(CZ) 7F14308 Institutional support: RVO:67985904 Keywords : Huntington ´s disease * huntingtin * induced pluripotent stem cells Subject RIV: FH - Neurology

Pulse width modulated buck-boost five-level current source inverters

DEFF Research Database (Denmark)

Blaabjerg, Frede; Gao, F.; Loh, P.C.

2008-01-01

, resulting in the natural balance of input current. For maintaining the normalized volt-sec average unchanged, the alternative phase opposition disposition (APOD) modulation scheme with typical gating signal mapping technique from voltage source inverter (VSI) to CSI can be assumed to control the five......This paper presents new five-level current source inverters (CSIs) with voltage/current buck-boost capability. Being different from the existing multilevel CSI, the proposed CSIs were first designed to regulate the flowing path of dc input current by controlling two additional active switches......-level buck-boost CSIs. Next by observing the hidden current charging path during inductive charging interval under APOD modulation, it is noted that the buck-boost five-level CSI can then be further modified with lesser active component without degrading output performance. To verify the theoretical findings...

Modulation Schemes of Multi-phase Three-Level Z-Source Inverters

DEFF Research Database (Denmark)

Gao, F.; Loh, P.C.; Blaabjerg, Frede

2007-01-01

different modulation requirement and output performance. For clearly illustrating the detailed modulation process, time domain analysis instead of the traditional multi-dimensional space vector demonstration is assumed which reveals the right way to insert shoot-through durations in the switching sequence...... with minimal commutation count. Lastly, the theoretical findings are verified in Matlab/PLECS simulation and experimentally using constructed laboratory prototypes.......This paper investigates the modulation schemes of three-level multiphase Z-source inverters with either two Z-source networks or single Z-source network connected between the dc sources and inverter circuitry. With the proper offset added for achieving both desired four-leg operation and optimized...

Dosimetric analysis of testicular doses in prostate intensity-modulated and volumetric-modulated arc radiation therapy at different energy levels

Energy Technology Data Exchange (ETDEWEB)

Onal, Cem, E-mail: hcemonal@hotmail.com; Arslan, Gungor; Dolek, Yemliha; Efe, Esma

2016-01-01

The aim of this study is to evaluate the incidental testicular doses during prostate radiation therapy with intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc radiotherapy (VMAT) at different energies. Dosimetric data of 15 patients with intermediate-risk prostate cancer who were treated with radiotherapy were analyzed. The prescribed dose was 78 Gy in 39 fractions. Dosimetric analysis compared testicular doses generated by 7-field intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy with a single arc at 6, 10, and 15 MV energy levels. Testicular doses calculated from the treatment planning system and doses measured from the detectors were analyzed. Mean testicular doses from the intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy per fraction calculated in the treatment planning system were 16.3 ± 10.3 cGy vs 21.5 ± 11.2 cGy (p = 0.03) at 6 MV, 13.4 ± 10.4 cGy vs 17.8 ± 10.7 cGy (p = 0.04) at 10 MV, and 10.6 ± 8.5 cGy vs 14.5 ± 8.6 cGy (p = 0.03) at 15 MV, respectively. Mean scattered testicular doses in the phantom measurements were 99.5 ± 17.2 cGy, 118.7 ± 16.4 cGy, and 193.9 ± 14.5 cGy at 6, 10, and 15 MV, respectively, in the intensity-modulated radiotherapy plans. In the volumetric-modulated arc radiotherapy plans, corresponding testicular doses per course were 90.4 ± 16.3 cGy, 103.6 ± 16.4 cGy, and 139.3 ± 14.6 cGy at 6, 10, and 15 MV, respectively. In conclusions, this study was the first to measure the incidental testicular doses by intensity-modulated radiotherapy and volumetric-modulated arc radiotherapy plans at different energy levels during prostate-only irradiation. Higher photon energy and volumetric-modulated arc radiotherapy plans resulted in higher incidental testicular doses compared with lower photon energy and intensity-modulated radiotherapy plans.

47 CFR 73.1570 - Modulation levels: AM, FM, TV and Class A TV aural.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Modulation levels: AM, FM, TV and Class A TV... levels: AM, FM, TV and Class A TV aural. (a) The percentage of modulation is to be maintained at as high a level as is consistent with good quality of transmission and good broadcast service, with maximum...

A novel humanized mouse model of Huntington disease for preclinical development of therapeutics targeting mutant huntingtin alleles

DEFF Research Database (Denmark)

Southwell, Amber L; Skotte, Niels H; Villanueva, Erika B

2017-01-01

transgenes in Hu128/21 mice match the human HTT exon 1 reference sequence. Conversely, the BACHD transgene carries a floxed, synthetic exon 1 sequence. Hu128/21 mice will be useful for investigations of human HTT that cannot be addressed in Hu97/18 mice, for developing therapies targeted to exon 1......Huntington disease (HD) is a neurodegenerative disease caused by a mutation in the huntingtin (HTT) gene. HTT is a large protein, interacts with many partners and is involved in many cellular pathways, which are perturbed in HD. Therapies targeting HTT directly are likely to provide the most global......-length, genomic human HTT transgenes heterozygous for the HD mutation and polymorphisms associated with HD in populations of East Asian descent and in a minority of patients from other ethnic groups. Hu128/21 mice display a wide variety of HD-like phenotypes that are similar to YAC128 mice. Additionally, both...

Huntingtin-interacting protein 14 is a type 1 diabetes candidate protein regulating insulin secretion and β-cell apoptosis

DEFF Research Database (Denmark)

Berchtold, Lukas Adrian; Størling, Zenia Marian; Ortis, Fernanda

2011-01-01

Type 1 diabetes (T1D) is a complex disease characterized by the loss of insulin-secreting β-cells. Although the disease has a strong genetic component, and several loci are known to increase T1D susceptibility risk, only few causal genes have currently been identified. To identify disease...... genes in T1D, including the INS gene. An unexpected top-scoring candidate gene was huntingtin-interacting protein (HIP)-14/ZDHHC17. Immunohistochemical analysis of pancreatic sections demonstrated that HIP14 is almost exclusively expressed in insulin-positive cells in islets of Langerhans. RNAi...... knockdown experiments established that HIP14 is an antiapoptotic protein required for β-cell survival and glucose-stimulated insulin secretion. Proinflammatory cytokines (IL-1β and IFN-γ) that mediate β-cell dysfunction in T1D down-regulated HIP14 expression in insulin-secreting INS-1 cells and in isolated...

ATLAS Level-1 Calorimeter Trigger Subsystem Tests of a Prototype Cluster Processor Module

CERN Document Server

Garvey, J; Apostologlou, P; Ay, C; Barnett, B M; Bauss, B; Brawn, I P; Bohm, C; Dahlhoff, A; Davis, A O; Edwards, J; Eisenhandler, E F; Gee, C N P; Gillman, A R; Hanke, P; Hellman, S; Hidévgi, A; Hillier, S J; Jakobs, K; Kluge, E E; Landon, M; Mahboubi, K; Mahout, G; Meier, K; Meshkov, P; Moye, T H; Mills, D; Moyse, E; Nix, O; Penno, K; Perera, V J O; Qian, W; Schmitt, K; Schäfer, U; Silverstein, S; Staley, R J; Thomas, J; Trefzger, T M; Watkins, P M; Watson, A; 9th Workshop On Electronics For LHC Experiments - LECC 2003

2003-01-01

The Level-1 Calorimeter Trigger consists of a Preprocessor (PP), a Cluster Processor (CP), and a Jet/Energy-sum Processor (JEP). The CP and JEP receive digitised trigger-tower data from the Preprocessor and produce trigger multiplicity and Region-of-Interest (RoI) information. The trigger will also provide intermediate results to the data acquisition (DAQ) system for monitoring and diagnostic purposes by using Readout Driver (ROD) Modules. The CP Modules (CPM) are designed to find isolated electron/photon and hadron/tau clusters in overlapping windows of trigger towers. Each pipelined CPM processes 8-bit data from a total of 128 trigger towers at each LHC crossing. Four full-specification prototypes of CPMs have been built and results of complete tests on individual boards will be presented. These modules were then integrated with other modules to build an ATLAS Level-1 Calorimeter Trigger subsystem test bench. Realtime data were exchanged between modules, and time-slice readout data were tagged and transferr...

Photovoltaic Shading Testbed for Module-Level Power Electronics: 2016 Performance Data Update

Energy Technology Data Exchange (ETDEWEB)

Deline, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meydbray, Jenya [PV Evolution Labs (PVEL), Davis, CA (United States); Donovan, Matt [PV Evolution Labs (PVEL), Davis, CA (United States)

2016-09-01

The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit of distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.

Discovery of novel isoforms of huntingtin reveals a new hominid-specific exon.

Directory of Open Access Journals (Sweden)

Albert Ruzo

Full Text Available Huntington's disease (HD is a devastating neurological disorder that is caused by an expansion of the poly-Q tract in exon 1 of the Huntingtin gene (HTT. HTT is an evolutionarily conserved and ubiquitously expressed protein that has been linked to a variety of functions including transcriptional regulation, mitochondrial function, and vesicle transport. This large protein has numerous caspase and calpain cleavage sites and can be decorated with several post-translational modifications such as phosphorylations, acetylations, sumoylations, and palmitoylations. However, the exact function of HTT and the role played by its modifications in the cell are still not well understood. Scrutiny of HTT function has been focused on a single, full length mRNA. In this study, we report the discovery of 5 novel HTT mRNA splice isoforms that are expressed in normal and HTT-expanded human embryonic stem cell (hESC lines as well as in cortical neurons differentiated from hESCs. Interestingly, none of the novel isoforms generates a truncated protein. Instead, 4 of the 5 new isoforms specifically eliminate domains and modifications to generate smaller HTT proteins. The fifth novel isoform incorporates a previously unreported additional exon, dubbed 41b, which is hominid-specific and introduces a potential phosphorylation site in the protein. The discovery of this hominid-specific isoform may shed light on human-specific pathogenic mechanisms of HTT, which could not be investigated with current mouse models of the disease.

Discovery of Novel Isoforms of Huntingtin Reveals a New Hominid-Specific Exon

Science.gov (United States)

Popowski, Melissa; Haremaki, Tomomi; Croft, Gist F.; Deglincerti, Alessia; Brivanlou, Ali H.

2015-01-01

Huntington’s disease (HD) is a devastating neurological disorder that is caused by an expansion of the poly-Q tract in exon 1 of the Huntingtin gene (HTT). HTT is an evolutionarily conserved and ubiquitously expressed protein that has been linked to a variety of functions including transcriptional regulation, mitochondrial function, and vesicle transport. This large protein has numerous caspase and calpain cleavage sites and can be decorated with several post-translational modifications such as phosphorylations, acetylations, sumoylations, and palmitoylations. However, the exact function of HTT and the role played by its modifications in the cell are still not well understood. Scrutiny of HTT function has been focused on a single, full length mRNA. In this study, we report the discovery of 5 novel HTT mRNA splice isoforms that are expressed in normal and HTT-expanded human embryonic stem cell (hESC) lines as well as in cortical neurons differentiated from hESCs. Interestingly, none of the novel isoforms generates a truncated protein. Instead, 4 of the 5 new isoforms specifically eliminate domains and modifications to generate smaller HTT proteins. The fifth novel isoform incorporates a previously unreported additional exon, dubbed 41b, which is hominid-specific and introduces a potential phosphorylation site in the protein. The discovery of this hominid-specific isoform may shed light on human-specific pathogenic mechanisms of HTT, which could not be investigated with current mouse models of the disease. PMID:26010866

Women's hormone levels modulate the motivational salience of facial attractiveness and sexual dimorphism.

Science.gov (United States)

Wang, Hongyi; Hahn, Amanda C; Fisher, Claire I; DeBruine, Lisa M; Jones, Benedict C

2014-12-01

The physical attractiveness of faces is positively correlated with both behavioral and neural measures of their motivational salience. Although previous work suggests that hormone levels modulate women's perceptions of others' facial attractiveness, studies have not yet investigated whether hormone levels also modulate the motivational salience of facial characteristics. To address this issue, we investigated the relationships between within-subject changes in women's salivary hormone levels (estradiol, progesterone, testosterone, and estradiol-to-progesterone ratio) and within-subject changes in the motivational salience of attractiveness and sexual dimorphism in male and female faces. The motivational salience of physically attractive faces in general and feminine female faces, but not masculine male faces, was greater in test sessions where women had high testosterone levels. Additionally, the reward value of sexually dimorphic faces in general and attractive female faces, but not attractive male faces, was greater in test sessions where women had high estradiol-to-progesterone ratios. These results provide the first evidence that the motivational salience of facial attractiveness and sexual dimorphism is modulated by within-woman changes in hormone levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Modulation Methods for Three-level Neutral-Point-Clamped Inverter Achieving Stress Redistribution under Moderate Modulation Index

DEFF Research Database (Denmark)

Ma, Ke; Blaabjerg, Frede

2016-01-01

This letter investigates the loss and thermal behaviors of a three-level neutral-point-clamped (3L-NPC) inverter undergoing moderate modulation index, which is typically presented during minor voltage sags of the power grid or speed changes of the electric machines. A series of new space vector m...

Spatial modulation of the Fermi level by coherent illumination of undoped GaAs

Science.gov (United States)

Nolte, D. D.; Olson, D. H.; Glass, A. M.

1989-11-01

The Fermi level in undoped GaAs has been modulated spatially by optically quenching EL2 defects. The spatial gradient of the Fermi level produces internal electric fields that are much larger than fields generated by thermal diffusion alone. The resulting band structure is equivalent to a periodic modulation-doped p-i-p structure of alternating insulating and p-type layers. The internal fields are detected via the electro-optic effect by the diffraction of a probe laser in a four-wave mixing geometry. The direct control of the Fermi level distinguishes this phenomenon from normal photorefractive behavior and introduces a novel nonlinear optical process.

A new Caenorhabditis elegans model of human huntingtin 513 aggregation and toxicity in body wall muscles.

Directory of Open Access Journals (Sweden)

Amy L Lee

Full Text Available Expanded polyglutamine repeats in different proteins are the known determinants of at least nine progressive neurodegenerative disorders whose symptoms include cognitive and motor impairment that worsen as patients age. One such disorder is Huntington's Disease (HD that is caused by a polyglutamine expansion in the human huntingtin protein (htt. The polyglutamine expansion destabilizes htt leading to protein misfolding, which in turn triggers neurodegeneration and the disruption of energy metabolism in muscle cells. However, the molecular mechanisms that underlie htt proteotoxicity have been somewhat elusive, and the muscle phenotypes have not been well studied. To generate tools to elucidate the basis for muscle dysfunction, we engineered Caenorhabditis elegans to express a disease-associated 513 amino acid fragment of human htt in body wall muscle cells. We show that this htt fragment aggregates in C. elegans in a polyglutamine length-dependent manner and is toxic. Toxicity manifests as motor impairment and a shortened lifespan. Compared to previous models, the data suggest that the protein context in which a polyglutamine tract is embedded alters aggregation propensity and toxicity, likely by affecting interactions with the muscle cell environment.

System Level Design of a Continuous-Time Delta-Sigma Modulator for Portable Ultrasound Scanners

DEFF Research Database (Denmark)

Llimos Muntal, Pere; Færch, Kjartan; Jørgensen, Ivan Harald Holger

2015-01-01

In this paper the system level design of a continuous-time ∆Σ modulator for portable ultrasound scanners is presented. The overall required signal-to-noise ratio (SNR) is derived to be 42 dB and the sampling frequency used is 320 MHz for an oversampling ratio of 16. In order to match these requir......, based on high-level VerilogA simulations, the performance of the ∆Σ modulator versus various block performance parameters is presented as trade-off curves. Based on these results, the block specifications are derived.......In this paper the system level design of a continuous-time ∆Σ modulator for portable ultrasound scanners is presented. The overall required signal-to-noise ratio (SNR) is derived to be 42 dB and the sampling frequency used is 320 MHz for an oversampling ratio of 16. In order to match...

Loss of Huntingtin stimulates capture of retrograde dense-core vesicles to increase synaptic neuropeptide stores.

Science.gov (United States)

Bulgari, Dinara; Deitcher, David L; Levitan, Edwin S

2017-08-01

The Huntington's disease protein Huntingtin (Htt) regulates axonal transport of dense-core vesicles (DCVs) containing neurotrophins and neuropeptides. DCVs travel down axons to reach nerve terminals where they are either captured in synaptic boutons to support later release or reverse direction to reenter the axon as part of vesicle circulation. Currently, the impact of Htt on DCV dynamics in the terminal is unknown. Here we report that knockout of Drosophila Htt selectively reduces retrograde DCV flux at proximal boutons of motoneuron terminals. However, initiation of retrograde transport at the most distal bouton and transport velocity are unaffected suggesting that synaptic capture rate of these retrograde DCVs could be altered. In fact, tracking DCVs shows that retrograde synaptic capture efficiency is significantly elevated by Htt knockout or knockdown. Furthermore, synaptic boutons contain more neuropeptide in Htt knockout larvae even though bouton size, single DCV fluorescence intensity, neuropeptide release in response to electrical stimulation and subsequent activity-dependent capture are unaffected. Thus, loss of Htt increases synaptic capture as DCVs travel by retrograde transport through boutons resulting in reduced transport toward the axon and increased neuropeptide in the terminal. These results therefore identify native Htt as a regulator of synaptic capture and neuropeptide storage. Copyright © 2017 Elsevier GmbH. All rights reserved.

AAV-mediated delivery of the transcription factor XBP1s into the striatum reduces mutant Huntingtin aggregation in a mouse model of Huntington’s disease

International Nuclear Information System (INIS)

Zuleta, Amparo; Vidal, Rene L.; Armentano, Donna; Parsons, Geoffrey; Hetz, Claudio

2012-01-01

Highlights: ► The contribution of ER stress to HD has not been directly addressed. ► Expression of XBP1s using AAVs decreases Huntingtin aggregation in vivo. ► We describe a new in vivo model of HD based on the expression of a large fragment of mHtt-RFP. -- Abstract: Huntington’s disease (HD) is caused by mutations that expand a polyglutamine region in the amino-terminal domain of Huntingtin (Htt), leading to the accumulation of intracellular inclusions and progressive neurodegeneration. Recent reports indicate the engagement of endoplasmic reticulum (ER) stress responses in human HD post mortem samples and animal models of the disease. Adaptation to ER stress is mediated by the activation of the unfolded protein response (UPR), an integrated signal transduction pathway that attenuates protein folding stress by controlling the expression of distinct transcription factors including X-Box binding protein 1 (XBP1). Here we targeted the expression of XBP1 on a novel viral-based model of HD. We delivered an active form of XBP1 locally into the striatum of adult mice using adeno-associated vectors (AAVs) and co-expressed this factor with a large fragment of mutant Htt as a fusion protein with RFP (Htt588 Q95 -mRFP) to directly visualize the accumulation of Htt inclusions in the brain. Using this approach, we observed a significant reduction in the accumulation of Htt588 Q95 -mRFP intracellular inclusion when XBP1 was co-expressed in the striatum. These results contrast with recent findings indicating a protective effect of XBP1 deficiency in neurodegeneration using knockout mice, and suggest a potential use of gene therapy strategies to manipulate the UPR in the context of HD.

∑∆ Modulator System-Level Considerations for Hearing-Aid Audio Class-D Output Stage Application

DEFF Research Database (Denmark)

Pracný, Peter; Bruun, Erik

2012-01-01

This paper deals with a system-level design of a digital sigma-delta (∑∆) modulator for hearing-aid audio Class D output stage application. The aim of this paper is to provide a thorough discussion on various possibilities and tradeoffs of ∑∆ modulator system-level design parameter combinations...... - order, oversampling ratio (OSR) and number of bits in the quantizer - including their impact on interpolation filter design as well. The system is kept in digital domain up to the input of the Class D power stage including the digital pulse width modulation (DPWM) block. Notes on the impact of the DPWM...

The Wnt receptor Ryk reduces neuronal and cell survival capacity by repressing FOXO activity during the early phases of mutant huntingtin pathogenicity.

Directory of Open Access Journals (Sweden)

Cendrine Tourette

2014-06-01

Full Text Available The Wnt receptor Ryk is an evolutionary-conserved protein important during neuronal differentiation through several mechanisms, including γ-secretase cleavage and nuclear translocation of its intracellular domain (Ryk-ICD. Although the Wnt pathway may be neuroprotective, the role of Ryk in neurodegenerative disease remains unknown. We found that Ryk is up-regulated in neurons expressing mutant huntingtin (HTT in several models of Huntington's disease (HD. Further investigation in Caenorhabditis elegans and mouse striatal cell models of HD provided a model in which the early-stage increase of Ryk promotes neuronal dysfunction by repressing the neuroprotective activity of the longevity-promoting factor FOXO through a noncanonical mechanism that implicates the Ryk-ICD fragment and its binding to the FOXO co-factor β-catenin. The Ryk-ICD fragment suppressed neuroprotection by lin-18/Ryk loss-of-function in expanded-polyQ nematodes, repressed FOXO transcriptional activity, and abolished β-catenin protection of mutant htt striatal cells against cell death vulnerability. Additionally, Ryk-ICD was increased in the nucleus of mutant htt cells, and reducing γ-secretase PS1 levels compensated for the cytotoxicity of full-length Ryk in these cells. These findings reveal that the Ryk-ICD pathway may impair FOXO protective activity in mutant polyglutamine neurons, suggesting that neurons are unable to efficiently maintain function and resist disease from the earliest phases of the pathogenic process in HD.

Huntington's disease accelerates epigenetic aging of human brain and disrupts DNA methylation levels.

Science.gov (United States)

Horvath, Steve; Langfelder, Peter; Kwak, Seung; Aaronson, Jeff; Rosinski, Jim; Vogt, Thomas F; Eszes, Marika; Faull, Richard L M; Curtis, Maurice A; Waldvogel, Henry J; Choi, Oi-Wa; Tung, Spencer; Vinters, Harry V; Coppola, Giovanni; Yang, X William

2016-07-01

Age of Huntington's disease (HD) motoric onset is strongly related to the number of CAG trinucleotide repeats in the huntingtin gene, suggesting that biological tissue age plays an important role in disease etiology. Recently, a DNA methylation based biomarker of tissue age has been advanced as an epigenetic aging clock. We sought to inquire if HD is associated with an accelerated epigenetic age. DNA methylation data was generated for 475 brain samples from various brain regions of 26 HD cases and 39 controls. Overall, brain regions from HD cases exhibit a significant epigenetic age acceleration effect (p=0.0012). A multivariate model analysis suggests that HD status increases biological age by 3.2 years. Accelerated epigenetic age can be observed in specific brain regions (frontal lobe, parietal lobe, and cingulate gyrus). After excluding controls, we observe a negative correlation (r=-0.41, p=5.5×10-8) between HD gene CAG repeat length and the epigenetic age of HD brain samples. Using correlation network analysis, we identify 11 co-methylation modules with a significant association with HD status across 3 broad cortical regions. In conclusion, HD is associated with an accelerated epigenetic age of specific brain regions and more broadly with substantial changes in brain methylation levels.

Conformational targeting of fibrillar polyglutamine proteins in live cells escalates aggregation and cytotoxicity.

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Erik Kvam

2009-05-01

Full Text Available Misfolding- and aggregation-prone proteins underlying Parkinson's, Huntington's and Machado-Joseph diseases, namely alpha-synuclein, huntingtin, and ataxin-3 respectively, adopt numerous intracellular conformations during pathogenesis, including globular intermediates and insoluble amyloid-like fibrils. Such conformational diversity has complicated research into amyloid-associated intracellular dysfunction and neurodegeneration. To this end, recombinant single-chain Fv antibodies (scFvs are compelling molecular tools that can be selected against specific protein conformations, and expressed inside cells as intrabodies, for investigative and therapeutic purposes.Using atomic force microscopy (AFM and live-cell fluorescence microscopy, we report that a human scFv selected against the fibrillar form of alpha-synuclein targets isomorphic conformations of misfolded polyglutamine proteins. When expressed in the cytoplasm of striatal cells, this conformation-specific intrabody co-localizes with intracellular aggregates of misfolded ataxin-3 and a pathological fragment of huntingtin, and enhances the aggregation propensity of both disease-linked polyglutamine proteins. Using this intrabody as a tool for modulating the kinetics of amyloidogenesis, we show that escalating aggregate formation of a pathologic huntingtin fragment is not cytoprotective in striatal cells, but rather heightens oxidative stress and cell death as detected by flow cytometry. Instead, cellular protection is achieved by suppressing aggregation using a previously described intrabody that binds to the amyloidogenic N-terminus of huntingtin. Analogous cytotoxic results are observed following conformational targeting of normal or polyglutamine-expanded human ataxin-3, which partially aggregate through non-polyglutamine domains.These findings validate that the rate of aggregation modulates polyglutamine-mediated intracellular dysfunction, and caution that molecules designed to

Modulation cues influence binaural masking-level difference in masking-pattern experiments.

Science.gov (United States)

Nitschmann, Marc; Verhey, Jesko L

2012-03-01

Binaural masking patterns show a steep decrease in the binaural masking-level difference (BMLD) when masker and signal have no frequency component in common. Experimental threshold data are presented together with model simulations for a diotic masker centered at 250 or 500 Hz and a bandwidth of 10 or 100 Hz masking a sinusoid interaurally in phase (S(0)) or in antiphase (S(π)). Simulations with a binaural model, including a modulation filterbank for the monaural analysis, indicate that a large portion of the decrease in the BMLD in remote-masking conditions may be due to an additional modulation cue available for monaural detection. © 2012 Acoustical Society of America

Modulation of C. elegans Touch Sensitivity Is Integrated at Multiple Levels

Science.gov (United States)

Chen, Xiaoyin

2014-01-01

Sensory systems can adapt to different environmental signals. Here we identify four conditions that modulate anterior touch sensitivity in Caenorhabditis elegans after several hours and demonstrate that such sensory modulation is integrated at multiple levels to produce a single output. Prolonged vibration involving integrin signaling directly sensitizes the touch receptor neurons (TRNs). In contrast, hypoxia, the dauer state, and high salt reduce touch sensitivity by preventing the release of long-range neuroregulators, including two insulin-like proteins. Integration of these latter inputs occurs at upstream neurohormonal cells and at the insulin signaling cascade within the TRNs. These signals and those from integrin signaling converge to modulate touch sensitivity by regulating AKT kinases and DAF-16/FOXO. Thus, activation of either the integrin or insulin pathways can compensate for defects in the other pathway. This modulatory system integrates conflicting signals from different modalities, and adapts touch sensitivity to both mechanical and non-mechanical conditions. PMID:24806678

Striking similarity in the gene expression levels of individual Myc module members among ESCs, EpiSCs, and partial iPSCs.

Directory of Open Access Journals (Sweden)

Masataka Hirasaki

Full Text Available Predominant transcriptional subnetworks called Core, Myc, and PRC modules have been shown to participate in preservation of the pluripotency and self-renewality of embryonic stem cells (ESCs. Epiblast stem cells (EpiSCs are another cell type that possesses pluripotency and self-renewality. However, the roles of these modules in EpiSCs have not been systematically examined to date. Here, we compared the average expression levels of Core, Myc, and PRC module genes between ESCs and EpiSCs. EpiSCs showed substantially higher and lower expression levels of PRC and Core module genes, respectively, compared with those in ESCs, while Myc module members showed almost equivalent levels of average gene expression. Subsequent analyses revealed that the similarity in gene expression levels of the Myc module between these two cell types was not just overall, but striking similarities were evident even when comparing the expression of individual genes. We also observed equivalent levels of similarity in the expression of individual Myc module genes between induced pluripotent stem cells (iPSCs and partial iPSCs that are an unwanted byproduct generated during iPSC induction. Moreover, our data demonstrate that partial iPSCs depend on a high level of c-Myc expression for their self-renewal properties.

Space Vector Pulse Width Modulation Strategy for Single-Phase Three-Level CIC T-source Inverter

DEFF Research Database (Denmark)

Shults, Tatiana E.; Husev, Oleksandr O.; Blaabjerg, Frede

2016-01-01

This paper presents a novel space vector pulse-width modulation strategy for a single-phase three-level buck-boost inverter based on an impedance-source network. The case study system is based on T-source inverter with continuous input current. To demonstrate the improved performance of the inver......This paper presents a novel space vector pulse-width modulation strategy for a single-phase three-level buck-boost inverter based on an impedance-source network. The case study system is based on T-source inverter with continuous input current. To demonstrate the improved performance...... of the inverter, the strategy was compared the traditional pulse-width modulation. It is shown that the approach proposed has fewer switching states and does not suffer from neutral point misbalance....

The Evidence for the Spread and Seeding Capacities of the Mutant Huntingtin Protein in in Vitro Systems and Their Therapeutic Implications

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Maria Masnata

2017-11-01

Full Text Available Neurodegenerative disorders are not only characterized by specific patterns of cell loss but the presence and accumulation of various pathological proteins—both of which correlate with disease evolution. There is now mounting evidence to suggest that these pathological proteins present with toxic, at times prion-like, properties and can therefore seed pathology in neighboring as well remotely connected healthy neurons as they spread across the brain. What is less clear, at this stage, is how much this actually contributes to, and drives, the core pathogenic events. In this review, we present a comprehensive, up-to-date summary of the reported in vitro studies that support the spreading and seeding capacities of pathological proteins, with an emphasis on mutant huntingtin protein in the context of Huntington's disease, although in vivo work remains to be performed to validate this theory in this particular disease. We have further reviewed these findings in light of their potential implications for the development of novel therapeutic approaches.

Personalising e-learning modules: targeting Rasmussen levels using XML.

Science.gov (United States)

Renard, J M; Leroy, S; Camus, H; Picavet, M; Beuscart, R

2003-01-01

The development of Internet technologies has made it possible to increase the number and the diversity of on-line resources for teachers and students. Initiatives like the French-speaking Virtual Medical University Project (UMVF) try to organise the access to these resources. But both teachers and students are working on a partly redundant subset of knowledge. From the analysis of some French courses we propose a model for knowledge organisation derived from Rasmussen's stepladder. In the context of decision-making Rasmussen has identified skill-based, rule-based and knowledge-based levels for the mental process. In the medical context of problem-solving, we apply these three levels to the definition of three students levels: beginners, intermediate-level learners, experts. Based on our model, we build a representation of the hierarchical structure of data using XML language. We use XSLT Transformation Language in order to filter relevant data according to student level and to propose an appropriate display on students' terminal. The model and the XML implementation we define help to design tools for building personalised e-learning modules.

Coherence modulation at the photon-counting level: A new scheme for secure communication

International Nuclear Information System (INIS)

Rhodes, William T; Boughanmi, Abdellatif; Moreno, Yezid Torres

2016-01-01

When operated at the photon-counting level, coherence modulation can provide quantifiably secure binary signal transmission between two entities, security being based on the nonclonability of photons. (paper)

Module-level DC/DC conversion for photovoltaic systems

NARCIS (Netherlands)

Bergveld, H.J.; Büthker, D.; Castello, C.; Doorn, T.S.; Jong, de A.; van Otten, R.; Waal, de K.

2011-01-01

Photovoltaic (PV) systems are increasingly used to generate electrical energy from solar irradiance incident on PV modules. Each PV module is formed by placing a large amount of PV cells, typically 60, in series. The PV system is then formed by placing a number, typically 10–12, of PV modules in

Modularity for Modulating Exercises and Levels

DEFF Research Database (Denmark)

Lund, Henrik Hautop; Nielsen, Camilla Balslev

2011-01-01

The modular interactive tiles aim at engaging anybody (elderly, carer, hospital personnel, children) in performing playful and motivating physical activities. Inspired by modular robotics, each tile is a self-contained module with processing power and communication to neighbouring modules....... In this paper, we investigate the therapeutic use. We show how the tiles are tested extensively with cardiac patients, COLD patients and stroke patients in hospitals and in the private homes of patients and elderly. We find that therapists are using the modular aspect of the tiles for personalized training...

Building America Case Study: Photovoltaic Systems with Module-Level Power Electronics

Energy Technology Data Exchange (ETDEWEB)

2015-09-01

Direct current (DC) power optimizers and microinverters (together known as module-level power electronics, or MLPE) are one of the fastest growing market segments in the solar industry. According to GTM Research in The Global PV Inverter Landscape 2015, over 55% of all residential photovoltaic (PV) installations in the United States used some form of MLPE in 2014.

Xyloketal-derived small molecules show protective effect by decreasing mutant Huntingtin protein aggregates in Caenorhabditis elegans model of Huntington’s disease

Directory of Open Access Journals (Sweden)

Zeng YX

2016-04-01

Full Text Available Yixuan Zeng,1,2,* Wenyuan Guo,1,* Guangqing Xu,3 Qinmei Wang,4 Luyang Feng,1,2 Simei Long,1 Fengyin Liang,1 Yi Huang,1 Xilin Lu,1 Shichang Li,5 Jiebin Zhou,5 Jean-Marc Burgunder,6 Jiyan Pang,5 Zhong Pei1,2 1Department of Neurology, National Key Clinical Department and Key Discipline of Neurology, Guangdong Key Laboratory for Diagnosis and Treatment of Major Neurological Disease, The First Affiliated Hospital, Sun Yat-sen University, 2Guangzhou Center, Chinese Huntington’s Disease Network, 3Department of Rehabilitation, The First Affiliated Hospital, 4Key laboratory on Assisted Circulation, Ministry of Health, Department of Cardiovascular Medicine of the First Affiliated Hospital, 5School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, Guangdong, People’s Republic of China; 6Swiss Huntington’s Disease Center, Department of Neurology, University of Bern, Bern, Switzerland *These authors contributed equally to this work Abstract: Huntington’s disease is an autosomal-dominant neurodegenerative disorder, with chorea as the most prominent manifestation. The disease is caused by abnormal expansion of CAG codon repeats in the IT15 gene, which leads to the expression of a glutamine-rich protein named mutant Huntingtin (Htt. Because of its devastating disease burden and lack of valid treatment, development of more effective therapeutics for Huntington’s disease is urgently required. Xyloketal B, a natural product from mangrove fungus, has shown protective effects against toxicity in other neurodegenerative disease models such as Parkinson’s and Alzheimer’s diseases. To identify potential neuroprotective molecules for Huntington’s disease, six derivatives of xyloketal B were screened in a Caenorhabditis elegans Huntington’s disease model; all six compounds showed a protective effect. Molecular docking studies indicated that compound 1 could bind to residues GLN369 and GLN393 of the mutant Htt protein, forming a

The data module, the missing link in high level control languages

International Nuclear Information System (INIS)

Crowley-Milling, M.C.

1979-01-01

In order to be able to use the full power and simplicity of a high level language for writing plant control programs, it must be possible to use the plant variables in the same manner as program variables, completely transparent to the address structure of the hardware and interface. Some of the high level languages provide facilities for writing procedures or subroutines to make this possible. However, most of the facilities provided share a number of disadvantages: they are usually relatively complicated for the user, involving passing many parameters which the programmer has to specify at each call; they usually have restrictions on the data types that can be used, and the data bases are normally organised to suit the interface system. However, the high level programmer is interested in the equipment to be controlled such as motors, pumps, power supplies, valves, etc., rather than the means of interfacing the equipment, and it greatly simplifies his task if he can call for actions on these items, using simple mnemonic names and a simple format. The design of the control system for the CERN 400 GeV proton accelerator, using a network of some thirty computers, provided the opportunity to try out a different approach, using an interpreter for the high-level control language NODAL, together with special functions which are called 'data modules'. The use of the data module and interpreter are described. (author)

Space vector modulation strategy for neutral-point voltage balancing in three-level inverter systems

DEFF Research Database (Denmark)

Choi, Uimin; Lee, Kyo Beum

2013-01-01

This study proposes a space vector modulation (SVM) strategy to balance the neutral-point voltage of three-level inverter systems. The proposed method is implemented by combining conventional symmetric SVM with nearest three-vector (NTV) modulation. The conventional SVM is converted to NTV...... modulation by properly adding or subtracting a minimum gate-on time. In addition, using this method, the switching frequency is reduced and a decrease of switching loss would be yielded. The neutral-point voltage is balanced by the proposed SVM strategy without additional hardware or complex calculations....... Simulation and experimental results are shown to verify the validity and feasibility of the proposed SVM strategy....

Topological Design and Modulation Strategy for Buck-Boost Three-Level Inverters

DEFF Research Database (Denmark)

Gao, Feng; Loh, Poh Chiang; Teodorescu, Remus

2009-01-01

To date, designed topologies for dc-ac inversion with both voltage buck and boost capabilities are mainly focused on two-level circuitries with extensions to three-level possibilities left nearly unexplored. Contributing to this area of research, this paper presents the design of a number of viable...... can perform distinct five-level line voltage and three-level phase voltage switching by simply controlling the active switches located in the designed voltage boost section of the circuits. As a cost saving option, one active switch can further be removed from the voltage boost section of the circuits...... buck-boost threelevel inverters that can also support bidirectional power conversion. The proposed front-end circuitry is developed from the C´ ukderived buck-boost two-level inverter, and by using the "alternative phase opposition disposition" modulation scheme, the buck-boost three-level inverters...

Discontinuous PWM Modulation Strategy with Circuit-Level Decoupling Concept of Three-Level Neutral-Point Clamped (NPC) Inverter

DEFF Research Database (Denmark)

Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.

2013-01-01

inverters, but also reduces the switching loss of the inverter along with an inherent neutral point (NP) voltage control. Based on a circuit-level decoupling concept, the NPC inverter can be decoupled into two three-level Buck converters in every defined operating section, and thereby the controller design...... can be reduced by one third. In order to explain the operation of this topology properly, the decoupling principle including the driving signal synthesis and the NP potential variation are analyzed in detail in this paper. Finally the viability and performance of the proposed modulation scheme...

Polymer-based 2D/3D wafer level heterogeneous integration for SSL module

NARCIS (Netherlands)

Yuan, C.; Wei, J.; Ye, H.; Koh, S.; Harianto, S.; Nieuwenhof, M.A. van den; Zhang, G.Q.

2012-01-01

This paper demonstrates a heterogeneous integration of solid state lighting (SSL) module, including light source (LED) and driver/control components. Such integration has been realized by the polymer-based reconfigured wafer level package technologies and such structure has been prototyped and

Two discrete components of the 20 Hz steady-state response are distinguished through the modulation of activation level

DEFF Research Database (Denmark)

Griskova, Inga; Mørup, Morten; Parnas, Josef

2009-01-01

Objective: To investigate the modulation of amplitude and phase precision of the auditory steady-state response (SSR) to 20 Hz stimulation in two conditions varying in the level of activation. Methods: Click stimuli (20 Hz) were applied while subjects were sitting upright silently reading a book......-negative multi-way factorization (NMWF). Results: The NMWF decomposition of amplitude and phase precision measures resulted in the observation of two distinct components: a component at the frequency of stimulation – 20 Hz SSR and a component emerging at 40 Hz – 20 Hz SSR-related 40 Hz activity. Modulation...... by the activation level was observed only for 20 Hz SSR-related 40 Hz activity as increased amplitude and phase precision during low activation level. No such effects were observed for 20 Hz SSR. Conclusion: The discrete components of the 20 Hz SSR are distinguished through modulation of activation level, 20 Hz SSR...

PSCAD modeling of a two-level space vector pulse width modulation algorithm for power electronics education

Directory of Open Access Journals (Sweden)

Ahmet Mete Vural

2016-09-01

Full Text Available This paper presents the design details of a two-level space vector pulse width modulation algorithm in PSCAD that is able to generate pulses for three-phase two-level DC/AC converters with two different switching patterns. The presented FORTRAN code is generic and can be easily modified to meet many other kinds of space vector modulation strategies. The code is also editable for hardware programming. The new component is tested and verified by comparing its output as six gating signals with those of a similar component in MATLAB library. Moreover the component is used to generate digital signals for closed-loop control of STATCOM for reactive power compensation in PSCAD. This add-on can be an effective tool to give students better understanding of the space vector modulation algorithm for different control tasks in power electronics area, and can motivate them for learning.

Nucleic Acid-Based Therapy Approaches for Huntington's Disease

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Tatyana Vagner

2012-01-01

Full Text Available Huntington's disease (HD is caused by a dominant mutation that results in an unstable expansion of a CAG repeat in the huntingtin gene leading to a toxic gain of function in huntingtin protein which causes massive neurodegeneration mainly in the striatum and clinical symptoms associated with the disease. Since the mutation has multiple effects in the cell and the precise mechanism of the disease remains to be elucidated, gene therapy approaches have been developed that intervene in different aspects of the condition. These approaches include increasing expression of growth factors, decreasing levels of mutant huntingtin, and restoring cell metabolism and transcriptional balance. The aim of this paper is to outline the nucleic acid-based therapeutic strategies that have been tested to date.

Adipose tissue branched chain amino acid (BCAA) metabolism modulates circulating BCAA levels.

Science.gov (United States)

Herman, Mark A; She, Pengxiang; Peroni, Odile D; Lynch, Christopher J; Kahn, Barbara B

2010-04-09

Whereas the role of adipose tissue in glucose and lipid homeostasis is widely recognized, its role in systemic protein and amino acid metabolism is less well-appreciated. In vitro and ex vivo experiments suggest that adipose tissue can metabolize substantial amounts of branched chain amino acids (BCAAs). However, the role of adipose tissue in regulating BCAA metabolism in vivo is controversial. Interest in the contribution of adipose tissue to BCAA metabolism has been renewed with recent observations demonstrating down-regulation of BCAA oxidation enzymes in adipose tissue in obese and insulin-resistant humans. Using gene set enrichment analysis, we observe alterations in adipose-tissue BCAA enzyme expression caused by adipose-selective genetic alterations in the GLUT4 glucose-transporter expression. We show that the rate of adipose tissue BCAA oxidation per mg of tissue from normal mice is higher than in skeletal muscle. In mice overexpressing GLUT4 specifically in adipose tissue, we observe coordinate down-regulation of BCAA metabolizing enzymes selectively in adipose tissue. This decreases BCAA oxidation rates in adipose tissue, but not in muscle, in association with increased circulating BCAA levels. To confirm the capacity of adipose tissue to modulate circulating BCAA levels in vivo, we demonstrate that transplantation of normal adipose tissue into mice that are globally defective in peripheral BCAA metabolism reduces circulating BCAA levels by 30% (fasting)-50% (fed state). These results demonstrate for the first time the capacity of adipose tissue to catabolize circulating BCAAs in vivo and that coordinate regulation of adipose-tissue BCAA enzymes may modulate circulating BCAA levels.

Scalable production in human cells and biochemical characterization of full-length normal and mutant huntingtin.

Directory of Open Access Journals (Sweden)

Bin Huang

Full Text Available Huntingtin (Htt is a 350 kD intracellular protein, ubiquitously expressed and mainly localized in the cytoplasm. Huntington's disease (HD is caused by a CAG triplet amplification in exon 1 of the corresponding gene resulting in a polyglutamine (polyQ expansion at the N-terminus of Htt. Production of full-length Htt has been difficult in the past and so far a scalable system or process has not been established for recombinant production of Htt in human cells. The ability to produce Htt in milligram quantities would be a prerequisite for many biochemical and biophysical studies aiming in a better understanding of Htt function under physiological conditions and in case of mutation and disease. For scalable production of full-length normal (17Q and mutant (46Q and 128Q Htt we have established two different systems, the first based on doxycycline-inducible Htt expression in stable cell lines, the second on "gutless" adenovirus mediated gene transfer. Purified material has then been used for biochemical characterization of full-length Htt. Posttranslational modifications (PTMs were determined and several new phosphorylation sites were identified. Nearly all PTMs in full-length Htt localized to areas outside of predicted alpha-solenoid protein regions. In all detected N-terminal peptides methionine as the first amino acid was missing and the second, alanine, was found to be acetylated. Differences in secondary structure between normal and mutant Htt, a helix-rich protein, were not observed in our study. Purified Htt tends to form dimers and higher order oligomers, thus resembling the situation observed with N-terminal fragments, although the mechanism of oligomer formation may be different.

Parametric resonances in the amplitude-modulated probe-field absorption spectrum of a two-level atom driven by a resonance amplitude- and phase-modulated pumping field

International Nuclear Information System (INIS)

Sushilov, N.V.; Kholodkevich, E.D.

1995-01-01

An analytical expression is derived for the polarization induced by a weak probe field with periodically modulated amplitude in a two-level medium saturated by a strong amplitude-and phase-modulated resonance field. It is shown that the absorption spectrum of the probe field includes parametric resonances, the maxima corresponding to the condition δ= 2nΓ-Ω w and the minima to that of δ= (2n + 1)Γ- w , where δ is the probe-field detuning front the resonance frequency, Ω w is the modulation frequency of the probe-field amplitude, and Γ is the transition line width, n = 1, 2, 3, hor-ellipsis. At the specific modulation parameters, a substantial region of negative values (i.e., the region of amplification without the population inversion) exists in the absorption spectrum of the probe field

Comparative Study of Modulation Techniques for Two-Level Voltage Source Inverters

Directory of Open Access Journals (Sweden)

Barry W. Williams

2016-06-01

Full Text Available A detailed comparative study of modulation techniques for single and three phase dc-ac inverters is presented.  Sinusoidal Pulse Width Modulation, Triplen Sinusoidal Pulse Width Modulation, Space Vector Modulation, Selective Harmonic Elimination and Wavelet Modulation are assessed and compared in terms of maximum fundamental output, harmonic performance, switching losses and operational mode.  The presented modulation techniques are applied to single and three phase voltage source inverters and are simulated using SIMULINK.  The simulation results clarify the inverter performance achieved using the different modulations techniques.

Enhanced 2/3 four-ary modulation code using soft-decision Viterbi decoding for four-level holographic data storage systems

Science.gov (United States)

Kong, Gyuyeol; Choi, Sooyong

2017-09-01

An enhanced 2/3 four-ary modulation code using soft-decision Viterbi decoding is proposed for four-level holographic data storage systems. While the previous four-ary modulation codes focus on preventing maximum two-dimensional intersymbol interference patterns, the proposed four-ary modulation code aims at maximizing the coding gains for better bit error rate performances. For achieving significant coding gains from the four-ary modulation codes, we design a new 2/3 four-ary modulation code in order to enlarge the free distance on the trellis through extensive simulation. The free distance of the proposed four-ary modulation code is extended from 1.21 to 2.04 compared with that of the conventional four-ary modulation code. The simulation result shows that the proposed four-ary modulation code has more than 1 dB gains compared with the conventional four-ary modulation code.

Robustness of MW-Level IGBT modules against gate oscillations under short circuit events

DEFF Research Database (Denmark)

Reigosa, Paula Diaz; Wu, Rui; Iannuzzo, Francesco

2015-01-01

The susceptibility of MW-level IGBT power modules to critical gate voltage oscillations during short circuit events has been evidenced experimentally. This paper proposes a sensitivity analysis method to better understand the oscillating behavior dependence on different operating conditions (i...... the oscillation phenomenon, as well as to further improve the device performance during short circuit....

Screening with an NMNAT2-MSD platform identifies small molecules that modulate NMNAT2 levels in cortical neurons.

Science.gov (United States)

Ali, Yousuf O; Bradley, Gillian; Lu, Hui-Chen

2017-03-07

Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) is a key neuronal maintenance factor and provides potent neuroprotection in numerous preclinical models of neurological disorders. NMNAT2 is significantly reduced in Alzheimer's, Huntington's, Parkinson's diseases. Here we developed a Meso Scale Discovery (MSD)-based screening platform to quantify endogenous NMNAT2 in cortical neurons. The high sensitivity and large dynamic range of this NMNAT2-MSD platform allowed us to screen the Sigma LOPAC library consisting of 1280 compounds. This library had a 2.89% hit rate, with 24 NMNAT2 positive and 13 negative modulators identified. Western analysis was conducted to validate and determine the dose-dependency of identified modulators. Caffeine, one identified NMNAT2 positive-modulator, when systemically administered restored NMNAT2 expression in rTg4510 tauopathy mice to normal levels. We confirmed in a cell culture model that four selected positive-modulators exerted NMNAT2-specific neuroprotection against vincristine-induced cell death while four selected NMNAT2 negative modulators reduced neuronal viability in an NMNAT2-dependent manner. Many of the identified NMNAT2 positive modulators are predicted to increase cAMP concentration, suggesting that neuronal NMNAT2 levels are tightly regulated by cAMP signaling. Taken together, our findings indicate that the NMNAT2-MSD platform provides a sensitive phenotypic screen to detect NMNAT2 in neurons.

Electromagnetic Cell Level Calibration for ATLAS Tile Calorimeter Modules

CERN Document Server

Kulchitskii, Yu A; Budagov, Yu A; Khubua, J I; Rusakovitch, N A; Vinogradov, V B; Henriques, A; Davidek, T; Tokar, S; Solodkov, A; Vichou, I

2006-01-01

We have determined the electromagnetic calibration constants of 11% TileCal modules exposed to electron beams with incident angles of 20 and 90 degrees. The gain of all the calorimeter cells have been pre-equalized using the radioactive Cs-source that will be also used in situ. The average values for these modules are equal to: for the flat filter method 1.154+/-0.002 pC/GeV and 1.192+/-0.002 pC/GeV for 20 and 90 degrees, for the fit method 1.040+/-0.002 pC/GeV and 1.068+/-0.003 pC/GeV, respectively. These average values for all cells of calibrated modules agree with the weighted average calibration constants for separate modules within the errors. Using the individual calibration constants for every module the RMS spread value of constants will be 1.9+/-0.1 %. In the case of the global constant this value will be 2.6+/-0.1 %. Finally, we present the global constants which should be used for the electromagnetic calibration of the ATLAS Tile hadronic calorimeter data in the ATHENA framework. These constants ar...

A Fast-Processing Modulation Strategy for Three-Phase Four-Leg Neutral-Point-Clamped Inverter Based on the Circuit-Level Decoupling Concept

DEFF Research Database (Denmark)

Ghoreishy, Hoda; Zhang, Zhe; Thomsen, Ole Cornelius

2012-01-01

In this paper, a modulation strategy based on the circuit-level decoupling concept is proposed and investigated for the three-level four-leg neutral-point-clamped (NPC) inverter,with the aim of delivering power to all sorts of loads, linear/nonlinear and balanced/unbalanced. By applying the propo......In this paper, a modulation strategy based on the circuit-level decoupling concept is proposed and investigated for the three-level four-leg neutral-point-clamped (NPC) inverter,with the aim of delivering power to all sorts of loads, linear/nonlinear and balanced/unbalanced. By applying...... the proposed modulation strategy, the four-leg NPC inverter can be decoupled into three three-level Buck converters in each defined operating section. This makes the controller design much simpler compared to the conventional four-leg NPC inverter controllers. Also, this technique can be implemented...

Optical polarization modulation by competing atomic coherence effects in a degenerate four-level Yb atomic system

International Nuclear Information System (INIS)

Park, Sung Jong; Park, Chang Yong; Yoon, Tai Hyun

2005-01-01

A scheme of optical polarization modulation of a linearly polarized infrared probe field is studied in a degenerate four-level Yb atomic system. We have observed an anomalous transmission spectra of two circular polarization components of the probe field exhibiting an enhanced two-photon absorption and a three-photon gain with comparable magnitude, leading to the lossless transmission and enhanced circular dichroism. We carried out a proof-of-principle experiment of fast optical polarization modulation in such a system by modulating the polarization state of the coupling field. The observed enhanced two-photon absorption and three-photon gain of the probe field are due to the result of competing atomic coherence effects

BACHD rats expressing full-length mutant huntingtin exhibit differences in social behavior compared to wild-type littermates.

Directory of Open Access Journals (Sweden)

Giuseppe Manfré

Full Text Available Huntington disease (HD is a devastating inherited neurodegenerative disorder characterized by progressive motor, cognitive, and psychiatric symptoms without any cure to slow down or stop the progress of the disease. The BACHD rat model for HD carrying the human full-length mutant huntingtin protein (mHTT with 97 polyQ repeats has been recently established as a promising model which reproduces several HD-like features. While motor and cognitive functions have been characterized in BACHD rats, little is known about their social phenotype.This study focuses especially on social behavior since evidence for social disturbances exists in human patients. Our objective was to compare social behavior in BACHD and wild-type (WT rats at different ages, using two different measures of sociability.Animals were tested longitudinally at the age of 2, 4 and 8 months in the social interaction test to examine different parameters of sociability. A separate cohort of 7 month old rats was tested in the three chamber social test to measure both sociability and social novelty. Gene expression analyses in 8 months old animals were performed by real time qRT-PCR to evaluate a potential involvement of D1 and D2 dopaminergic receptors and the contribution of Brain-derived neurotrophic factor (BDNF to the observed behavioral alterations.In the social interaction test, BACHD rats showed age-dependent changes in behaviour when they were-re introduced to their cagemate after a 24 hours-period of individual housing. The time spent on nape attacks increased with aging. Furthermore, a significant higher level of pinning at 2 months of age was shown in the BACHD rats compared to wild-types, followed by a reduction at 4 and 8 months. On the other hand, BACHD rats exhibited a decreased active social behaviour compared to wild-types, reflected by genotype-effects on approaching, following and social nose contact. In the three chamber social test, BACHD rats seemed to show a mild

BACHD rats expressing full-length mutant huntingtin exhibit differences in social behavior compared to wild-type littermates.

Science.gov (United States)

Manfré, Giuseppe; Novati, Arianna; Faccini, Ilaria; Rossetti, Andrea C; Bosch, Kari; Molteni, Raffaella; Riva, Marco A; Van der Harst, Johanneke E; Nguyen, Huu Phuc; Homberg, Judith R

2018-01-01

Huntington disease (HD) is a devastating inherited neurodegenerative disorder characterized by progressive motor, cognitive, and psychiatric symptoms without any cure to slow down or stop the progress of the disease. The BACHD rat model for HD carrying the human full-length mutant huntingtin protein (mHTT) with 97 polyQ repeats has been recently established as a promising model which reproduces several HD-like features. While motor and cognitive functions have been characterized in BACHD rats, little is known about their social phenotype. This study focuses especially on social behavior since evidence for social disturbances exists in human patients. Our objective was to compare social behavior in BACHD and wild-type (WT) rats at different ages, using two different measures of sociability. Animals were tested longitudinally at the age of 2, 4 and 8 months in the social interaction test to examine different parameters of sociability. A separate cohort of 7 month old rats was tested in the three chamber social test to measure both sociability and social novelty. Gene expression analyses in 8 months old animals were performed by real time qRT-PCR to evaluate a potential involvement of D1 and D2 dopaminergic receptors and the contribution of Brain-derived neurotrophic factor (BDNF) to the observed behavioral alterations. In the social interaction test, BACHD rats showed age-dependent changes in behaviour when they were-re introduced to their cagemate after a 24 hours-period of individual housing. The time spent on nape attacks increased with aging. Furthermore, a significant higher level of pinning at 2 months of age was shown in the BACHD rats compared to wild-types, followed by a reduction at 4 and 8 months. On the other hand, BACHD rats exhibited a decreased active social behaviour compared to wild-types, reflected by genotype-effects on approaching, following and social nose contact. In the three chamber social test, BACHD rats seemed to show a mild deficit in

BACHD rats expressing full-length mutant huntingtin exhibit differences in social behavior compared to wild-type littermates

Science.gov (United States)

Manfré, Giuseppe; Novati, Arianna; Faccini, Ilaria; Rossetti, Andrea C.; Bosch, Kari; Molteni, Raffaella; Riva, Marco A.; Van der Harst, Johanneke E.; Homberg, Judith R.

2018-01-01

Background Huntington disease (HD) is a devastating inherited neurodegenerative disorder characterized by progressive motor, cognitive, and psychiatric symptoms without any cure to slow down or stop the progress of the disease. The BACHD rat model for HD carrying the human full-length mutant huntingtin protein (mHTT) with 97 polyQ repeats has been recently established as a promising model which reproduces several HD-like features. While motor and cognitive functions have been characterized in BACHD rats, little is known about their social phenotype. Objective This study focuses especially on social behavior since evidence for social disturbances exists in human patients. Our objective was to compare social behavior in BACHD and wild-type (WT) rats at different ages, using two different measures of sociability. Methods Animals were tested longitudinally at the age of 2, 4 and 8 months in the social interaction test to examine different parameters of sociability. A separate cohort of 7 month old rats was tested in the three chamber social test to measure both sociability and social novelty. Gene expression analyses in 8 months old animals were performed by real time qRT-PCR to evaluate a potential involvement of D1 and D2 dopaminergic receptors and the contribution of Brain-derived neurotrophic factor (BDNF) to the observed behavioral alterations. Results In the social interaction test, BACHD rats showed age-dependent changes in behaviour when they were-re introduced to their cagemate after a 24 hours-period of individual housing. The time spent on nape attacks increased with aging. Furthermore, a significant higher level of pinning at 2 months of age was shown in the BACHD rats compared to wild-types, followed by a reduction at 4 and 8 months. On the other hand, BACHD rats exhibited a decreased active social behaviour compared to wild-types, reflected by genotype-effects on approaching, following and social nose contact. In the three chamber social test, BACHD rats

Binding, internalization and fate of Huntingtin Exon1 fibrillar assemblies in mitotic and nonmitotic neuroblastoma cells.

Science.gov (United States)

Ruiz-Arlandis, G; Pieri, L; Bousset, L; Melki, R

2016-02-01

The aggregation of Huntingtin (HTT) protein and of its moiety encoded by its Exon1 (HTTExon1) into fibrillar structures inside neurons is the molecular hallmark of Huntington's disease. Prion-like transmission of these aggregates between cells has been demonstrated. The cell-to-cell transmission mechanisms of these protein aggregates and the susceptibility of different kinds of neuronal cells to these toxic assemblies still need assessment. Here, we documented the binding to and internalization by differentiated and undifferentiated neuroblastoma cells of exogenous fibrillar HTTExon1 and polyglutamine (polyQ) polypeptides containing the same number of glutamines. We assessed the contribution of endocytosis to fibrillar HTTExon1 uptake, their intracellular localization and fate. We observed that undifferentiated neuroblastoma cells were more susceptible to fibrillar HTTExon1 and polyQ than their differentiated counterparts. Furthermore, we demonstrated that exogenous HTTExon1 aggregates are mainly taken up by endocytosis and directed to lysosomal compartments in both mitotic and quiescent cells. These data suggest that the rates of endocytic processes that differ in mitotic and quiescent cells strongly impact the uptake of exogenous HTTExon1 and polyQ fibrils. This may be either the consequence of distinct metabolisms or distributions of specific protein partners for amyloid-like assemblies at the surface of highly dividing versus quiescent cells. Our results highlight the importance of endocytic processes in the internalization of exogenous HTTExon1 fibrils and suggest that a proportion of those assemblies reach the cytosol where they can amplify by recruiting the endogenous protein after escaping, by yet an unknown process, from the endo-lysosomal compartments. © 2015 British Neuropathological Society.

Power penalties for multi-level PAM modulation formats at arbitrary bit error rates

Science.gov (United States)

Kaliteevskiy, Nikolay A.; Wood, William A.; Downie, John D.; Hurley, Jason; Sterlingov, Petr

2016-03-01

There is considerable interest in combining multi-level pulsed amplitude modulation formats (PAM-L) and forward error correction (FEC) in next-generation, short-range optical communications links for increased capacity. In this paper we derive new formulas for the optical power penalties due to modulation format complexity relative to PAM-2 and due to inter-symbol interference (ISI). We show that these penalties depend on the required system bit-error rate (BER) and that the conventional formulas overestimate link penalties. Our corrections to the standard formulas are very small at conventional BER levels (typically 1×10-12) but become significant at the higher BER levels enabled by FEC technology, especially for signal distortions due to ISI. The standard formula for format complexity, P = 10log(L-1), is shown to overestimate the actual penalty for PAM-4 and PAM-8 by approximately 0.1 and 0.25 dB respectively at 1×10-3 BER. Then we extend the well-known PAM-2 ISI penalty estimation formula from the IEEE 802.3 standard 10G link modeling spreadsheet to the large BER case and generalize it for arbitrary PAM-L formats. To demonstrate and verify the BER dependence of the ISI penalty, a set of PAM-2 experiments and Monte-Carlo modeling simulations are reported. The experimental results and simulations confirm that the conventional formulas can significantly overestimate ISI penalties at relatively high BER levels. In the experiments, overestimates up to 2 dB are observed at 1×10-3 BER.

Fractal analysis for assessing the level of modulation of IMRT fields

International Nuclear Information System (INIS)

Nauta, Marcel; Villarreal-Barajas, J. Eduardo; Tambasco, Mauro

2011-01-01

Purpose: To investigate the potential of three fractal dimension (FD) analysis methods (i.e., the variation, power spectrum, and variogram methods) as metrics for quantifying the degree of modulation in planned intensity modulated radiation therapy (IMRT) treatment fields, and compare the most suitable FD method to the number of monitor units (MUs), the average leaf gap, and the 2D modulation index (2D MI) for assessing modulation. Methods: The authors implemented, validated, and compared the variation, power spectrum, and variogram methods for computing the FD. Validation of the methods was done using mathematical fractional Brownian surfaces of known FD that ranged in size from 128 x 128 to 512 x 512. The authors used a test set consisting of seven head and neck carcinoma plans (50 prescribed treatment fields) to choose an FD cut-point that ensures no false positives (100% specificity) in distinguishing between moderate and high degrees of field modulation. The degree of field modulation was controlled by adjusting the fluence smoothing parameters in the Eclipse treatment planning system (Varian Medical Systems, Palo Alto, CA). The moderate modulation fields were representative of the degree of modulation used clinically at the authors' institution. The authors performed IMRT quality assurance (QA) on the 50 test fields using the MapCHECK device. The FD cut-point was applied to a validation set consisting of four head and neck plans (28 fields). The area under the curve (AUC) from receiver operating characteristic (ROC) analysis was used to compare the ability of FD, number of MUs, average leaf gap, and the 2D MI for distinguishing between the moderate and high modulation fields. Results: The authors found the variogram FD method to be the most suitable for assessing the modulation complexity of IMRT fields for head and neck carcinomas. Pass rates as measured by the gamma criterion for the MapCHECK IMRT field measurements were higher for the moderately modulated

Extended Pulse-Powered Humidity-Freeze Cycling for Testing Module-Level Power Electronics

Energy Technology Data Exchange (ETDEWEB)

Hacke, Peter L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rodriguez, Miguel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kempe, Michael D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Repins, Ingrid L [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-11-28

An EMI suppression capacitor (polypropylene film type) failed by 'popcorning' due to vapor outgassing in pulse powered humidity-freeze cycles. No shorts or shunts could be detected despite mildly corroded metallization visible in the failed capacitor. Humidity-freeze cycling is optimized to break into moisture barriers. However, further studies will be required on additional module level power electronic (MLPE) devices to optimize the stress testing for condensation to precipitate any weakness to short circuiting and other humidity/bias failure modes.

New Modulation Strategy to Balance the Neutral-Point Voltage for Three-Level Neutral-Clamped Inverter Systems

DEFF Research Database (Denmark)

Choi, Uimin; Lee, June-Seok; Lee, Kyo-Beum

2014-01-01

This paper proposes a new modulation strategy that balances the neutral-point voltage for three-level neutral-clamped inverter systems. The proposed modulation replaces the P-type or N-type small switching states with other switching states that do not affect the neutral-point voltage. The zero...... and medium switching states are employed to help the neutral-point voltage balancing. This method little bit increases the switching events and output total harmonic distortion. However, this method has a strong balancing ability at all regions. Further, it is very simple to implement in both space vector...

Achieving nonlinear optical modulation via four-wave mixing in a four-level atomic system

Science.gov (United States)

Li, Hai-Chao; Ge, Guo-Qin; Zubairy, M. Suhail

2018-05-01

We propose an accessible scheme for implementing tunable nonlinear optical amplification and attenuation via a synergetic mechanism of four-wave mixing (FWM) and optical interference in a four-level ladder-type atomic system. By constructing a cyclic atom-field interaction, we show that two reverse FWM processes can coexist via optical transitions in different branches. In the suitable input-field conditions, strong interference effects between the input fields and the generated FWM fields can be induced and result in large amplification and deep attenuation of the output fields. Moreover, such an optical modulation from enhancement to suppression can be controlled by tuning the relative phase. The quantum system can be served as a switchable optical modulator with potential applications in quantum nonlinear optics.

Intracellular calcium levels determine differential modulation of allosteric interactions within G protein-coupled receptor heteromers.

Science.gov (United States)

Navarro, Gemma; Aguinaga, David; Moreno, Estefania; Hradsky, Johannes; Reddy, Pasham P; Cortés, Antoni; Mallol, Josefa; Casadó, Vicent; Mikhaylova, Marina; Kreutz, Michael R; Lluís, Carme; Canela, Enric I; McCormick, Peter J; Ferré, Sergi

2014-11-20

The pharmacological significance of the adenosine A2A receptor (A2AR)-dopamine D2 receptor (D2R) heteromer is well established and it is being considered as an important target for the treatment of Parkinson’s disease and other neuropsychiatric disorders. However, the physiological factors that control its distinctive biochemical properties are still unknown. We demonstrate that different intracellular Ca2+ levels exert a differential modulation of A2AR-D2R heteromer-mediated adenylyl-cyclase and MAPK signaling in striatal cells. This depends on the ability of low and high Ca2+ levels to promote a selective interaction of the heteromer with the neuronal Ca2+-binding proteins NCS-1 and calneuron-1, respectively. These Ca2+-binding proteins differentially modulate allosteric interactions within the A2AR-D2R heteromer, which constitutes a unique cellular device that integrates extracellular (adenosine and dopamine) and intracellular (Ca+2) signals to produce a specific functional response.

Development of Chemistry Triangle Oriented Module on Topic of Reaction Rate for Senior High School Level Grade XI Chemistry Learning.

Science.gov (United States)

Sari, D. R.; Hardeli; Bayharti

2018-04-01

This study aims to produce chemistry triangle oriented module on topic of reaction rate, and to reveal the validity and practicality level of the generated module. The type of research used is EducationalDesign Research (EDR) with development model is Plompmodel. This model consists of three phases, which are preliminary research, prototyping phase, and assessment phase. The instrument used in this research is questionnaire validity and practicality. The data of the research were analyzed by using Kappa Cohen formula. The chemistry triangle oriented module validation sheet was given to 5 validators consisting of 3 chemistry lecturers and 2 high school chemistry teachers, while the practicality sheet was given to 2 chemistry teachers, 6 students of SMAN 10 Padang grade XII MIA 5 on the small groupevaluation and 25 students of SMAN 10 Padang grade XII MIA 6 on the field test. Based on the questionnaire validity analysis, the validity level of the module is very high with the value of kappa moment 0.87. The level of practicality based on teacher questionnaire response is very high category with a kappa moment value 0.96. Based on the questionnaire of student responses on small group evaluation, the level of practicality is very high category with a kappa moment 0.81, and the practicality is very high category with kappa moment value 0.83 based on questionnaire of student response on field test.

Carrier-based modulation schemes for various three-level matrix converters

DEFF Research Database (Denmark)

Blaabjerg, Frede; Loh, P.C.; Rong, R.C.

2008-01-01

different performance merits. To avoid confusion and hence fasten the converter applications in the industry, it would surely be better for modulation schemes to be developed from a common set of modulation principles that unfortunately has not yet been thoroughly defined. Contributing to that area...... a limited set of switching vectors because of its lower semiconductor count. Through simulation and experimental testing, all the evaluated matrix converters are shown to produce satisfactory sinusoidal input and output quantities using the same set of generic modulation principles, which can conveniently...

XPM-induced degradation of multilevel phase modulated channel caused by neighboring NRZ modulated channels

DEFF Research Database (Denmark)

Jensen, Jesper Bevensee; Schiellerup, G.; Peucheret, Christophe

2008-01-01

The impact of XPM from NRZ modulated channels on an 8-level phase modulated channel in a WDM system was investigated. Requirements on launch power are found. 400 km transmission was achieved with negligible penalty.......The impact of XPM from NRZ modulated channels on an 8-level phase modulated channel in a WDM system was investigated. Requirements on launch power are found. 400 km transmission was achieved with negligible penalty....

Modulation detection as a function of carrier frequency and level

NARCIS (Netherlands)

Fassel, R.; Kohlrausch, A.G.

1995-01-01

This paper describes recent experiments investigating temporal processing in the auditory system. Subjects had to discriminate sinusoidal signals with a flat temporal envelope from those with a sinusoidal amplitude modulation. The modulation depth at threshold was measured for a wide range of

Dialkylthio Substitution: An Effective Method to Modulate the Molecular Energy Levels of 2D-BDT Photovoltaic Polymers.

Science.gov (United States)

Yao, Huifeng; Zhang, Hao; Ye, Long; Zhao, Wenchao; Zhang, Shaoqing; Hou, Jianhui

2016-02-17

Dialkylthio-substituted thienyl-benzodithiophene (BDT-DST) was designed and synthesized as a building block to modulate the molecular levels of the conjugated polymers, and three copolymers named PDST-BDD, PDST-TT and PDST-DPP were prepared and applied in polymer solar cells (PSCs). Theoretical calculations and electrochemical cyclic voltammetry (CV) measurement suggested that the dialkylthio group could decrease the molecular energy levels of the resulting polymers distinctly. The open-circuit voltage (VOC) of PSC devices based on PDST-BDD, PDST-TT, and PDST-DPP are as high as 1.0, 0.98, and 0.88 V, respectively, which are ∼0.15 V higher than those of the corresponding alky-substituted analogues. Moreover, the influence of the dialkylthio group on the absorption spectra, crystalline properties, hole mobilities, and blend morphologies of the polymers was also investigated. The results indicate that the dialkythio substitution is an effective method to modulate the molecular energy levels and that the BDT-DST unit has potential for constructing high-efficiency photovoltaic polymers.

Experiments of Multi-Level Read-Only Recording Using Readout Signal Wave-Shape Modulation

International Nuclear Information System (INIS)

Yi, Tang; Jing, Pei; Long-Fa, Pan; Yi, Ni; Hua, Hu; Bu-Qing, Zhang

2008-01-01

An innovative multilevel read-only recording method is proposed. In this method, a short pit/land is deliberately inserted to the original land/pit. This modifies the wave-shape of readout signal. Taking the wave-shape as the symbol of level detection, a signal wave-shape modulation (SWSM) multilevel method is realized. This method is carried out and validated on the DVD read-only manufacture and readout system. A capacity of 15 GB can be expected, and a bit error rate of 10 −4 is achieved. The capacity can meet the demand of high definition movie publication. This method also provides a potential multi-level solution for other storage formats and systems. (fundamental areas of phenomenology (including applications))

Transgenic animal models for study of the pathogenesis of Huntington's disease and therapy.

Science.gov (United States)

Chang, Renbao; Liu, Xudong; Li, Shihua; Li, Xiao-Jiang

2015-01-01

Huntington's disease (HD) is caused by a genetic mutation that results in polyglutamine expansion in the N-terminal regions of huntingtin. As a result, this polyQ expansion leads to the misfolding and aggregation of mutant huntingtin as well as age-dependent neurodegeneration. The genetic mutation in HD allows for generating a variety of animal models that express different forms of mutant huntingtin and show differential pathology. Studies of these animal models have provided an important insight into the pathogenesis of HD. Mouse models of HD include transgenic mice, which express N-terminal or full-length mutant huntingtin ubiquitously or selectively in different cell types, and knock-in mice that express full-length mutant Htt at the endogenous level. Large animals, such as pig, sheep, and monkeys, have also been used to generate animal HD models. This review focuses on the different features of commonly used transgenic HD mouse models as well as transgenic large animal models of HD, and also discusses how to use them to identify potential therapeutics. Since HD shares many pathological features with other neurodegenerative diseases, identification of therapies for HD would also help to develop effective treatment for different neurodegenerative diseases that are also caused by protein misfolding and occur in an age-dependent manner.

Thermal Equilibrium Dynamic Control Based on DPWM Dual-Mode Modulation of High Power NPC Three-Level Inverter

Directory of Open Access Journals (Sweden)

Shi-Zhou Xu

2016-01-01

Full Text Available In some special applications of NPC three-level inverters, such as mine hoist, there exist special conditions of overloading during the whole hoisting process and large overload in starting stage, during which the power-loss calculation of power devices and thermal control are important factors affecting the thermal stability of inverters. The principles of SVPWM and DPWM were described in this paper firstly, based on which the dynamic power losses of the two modulations of hoist in single period were calculated. Secondly, a thermal equilibrium dynamic control based on DPMW dual-mode modulation was proposed, which can switch the modulation dynamically according to the change of dynamic power loss to realize dynamic control of power loss and thermal equilibrium of inverter. Finally, simulation and experiment prove the effectiveness of the proposed strategy.

Attention, working memory, and phenomenal experience of WM content: memory levels determined by different types of top-down modulation.

Science.gov (United States)

Jacob, Jane; Jacobs, Christianne; Silvanto, Juha

2015-01-01

What is the role of top-down attentional modulation in consciously accessing working memory (WM) content? In influential WM models, information can exist in different states, determined by allocation of attention; placing the original memory representation in the center of focused attention gives rise to conscious access. Here we discuss various lines of evidence indicating that such attentional modulation is not sufficient for memory content to be phenomenally experienced. We propose that, in addition to attentional modulation of the memory representation, another type of top-down modulation is required: suppression of all incoming visual information, via inhibition of early visual cortex. In this view, there are three distinct memory levels, as a function of the top-down control associated with them: (1) Nonattended, nonconscious associated with no attentional modulation; (2) attended, phenomenally nonconscious memory, associated with attentional enhancement of the actual memory trace; (3) attended, phenomenally conscious memory content, associated with enhancement of the memory trace and top-down suppression of all incoming visual input.

Decreased modulation by the risk level on the brain activation during decision making in adolescents with internet gaming disorder

Directory of Open Access Journals (Sweden)

Xin eQi

2015-11-01

Full Text Available Greater impulse and risk-taking and reduced decision-making ability were reported as the main behavioral impairments in individuals with Internet gaming disorder (IGD, which has become a serious mental health issue worldwide. However, it is not clear to date how the risk level modulates brain activity during the decision-making process in IGD individuals. In this study, 23 adolescents with IGD and 24 healthy controls (HCs without IGD were recruited, and the Balloon Analog Risk Task (BART was used in a functional magnetic resonance imaging (fMRI experiment to evaluate the modulation of the risk level (the probability of balloon explosion on brain activity during risky decisionmaking in IGD adolescents. Reduced modulation of the risk level on the activation of the right dorsolateral prefrontal cortex (DLPFC during the active BART was found in IGD group compared to the HCs. In the IGD group, there was a significant negative correlation between the risk-related DLPFC activation during the active BART and the Barratt impulsivity scale (BIS-11 scores, which were significantly higher in IGD group compared with the HCs. Our study demonstrated that, as a critical decision-making-related brain region, the right DLPFC is less sensitive to risk in IGD adolescents compared with the HCs, which may contribute to the higher impulsivity level in IGD adolescents.

Levels of conflict in reasoning modulate right lateral prefrontal cortex.

Science.gov (United States)

Stollstorff, Melanie; Vartanian, Oshin; Goel, Vinod

2012-01-05

Right lateral prefrontal cortex (rlPFC) has previously been implicated in logical reasoning under conditions of conflict. A functional magnetic resonance imaging (fMRI) study was conducted to explore its role in conflict more precisely. Specifically, we distinguished between belief-logic conflict and belief-content conflict, and examined the role of rlPFC under each condition. The results demonstrated that a specific region of rlPFC is consistently activated under both types of conflict. Moreover, the results of a parametric analysis demonstrated that the same region was modulated by the level of conflict contained in reasoning arguments. This supports the idea that this specific region is engaged to resolve conflict, including during deductive reasoning. This article is part of a Special Issue entitled "The Cognitive Neuroscience of Thought". Copyright © 2011 Elsevier B.V. All rights reserved.

Module-level DC/DC conversion for photovotaic systems : the delta-conversion concept

NARCIS (Netherlands)

Bergveld, H.J.; Büthker, D.; Castello, C.; Doorn, T.S.; Jong, de A.; van Otten, R.; Waal, de K.

2013-01-01

Photovoltaic (PV) systems are increasingly used to generate electrical energy from solar irradiation incident on PV modules. PV modules are formed by placing many PV cells in series. The PV system is then formed by placing a number of PV modules in series in a string. In practical cases, differences

Low level light in combination with metabolic modulators for effective therapy

Science.gov (United States)

Dong, Tingting; Zhang, Qi; Hamblin, Michael R.; Wu, Mei X.

2015-03-01

Vascular damage occurs frequently at the injured brain causing hypoxia and is associated with poor outcomes in the clinics. We found high levels of glycolysis, reduced ATP generation, and increased formation of reactive oxygen species (ROS) and apoptosis in neurons under hypoxia. Strikingly, these adverse events were reversed significantly by noninvasive exposure of injured brain to low-level light (LLL). LLL illumination sustained the mitochondrial membrane potential, constrained cytochrome C leakage in hypoxic cells, and protected them from apoptosis, underscoring a unique property of LLL. The effect of LLL was further bolstered by combination with metabolic substrates such as pyruvate or lactate both in vivo and in vitro. The combinational treatment retained memory and learning activities of injured mice to a normal level, whereas those treated with LLL or pyruvate alone, or sham light displayed partial or severe deficiency in these cognitive functions. In accordance with well-protected learning and memory function, the hippocampal region primarily responsible for learning and memory was completely protected by a combination of LLL and pyruvate, in marked contrast to the severe loss of hippocampal tissue due to secondary damage in control mice. These data clearly suggest that energy metabolic modulators can additively or synergistically enhance the therapeutic effect of LLL in energy-producing insufficient tissues like injured brain. Keywords:

Ghrelin-related peptides do not modulate vasodilator nitric oxide production or superoxide levels in mouse systemic arteries.

Science.gov (United States)

Ku, Jacqueline M; Sleeman, Mark W; Sobey, Christopher G; Andrews, Zane B; Miller, Alyson A

2016-04-01

The ghrelin gene is expressed in the stomach where it ultimately encodes up to three peptides, namely, acylated ghrelin, des-acylated ghrelin and obestatin, which all have neuroendocrine roles. Recently, the authors' reported that these peptides have important physiological roles in positively regulating vasodilator nitric oxide (NO) production in the cerebral circulation, and may normally suppress superoxide production by the pro-oxidant enzyme, Nox2-NADPH oxidase. To date, the majority of studies using exogenous peptides infer that they may have similar roles in the systemic circulation. Therefore, this study examined whether exogenous and endogenous ghrelin-related peptides modulate NO production and superoxide levels in mouse mesenteric arteries and/or thoracic aorta. Using wire myography, it was found that application of exogenous acylated ghrelin, des-acylated ghrelin or obestatin to mouse thoracic aorta or mesenteric arteries failed to elicit a vasorelaxation response, whereas all three peptides elicited vasorelaxation responses of rat thoracic aorta. Also, none of the peptides modulated mouse aortic superoxide levels as measured by L-012-enhanced chemiluminescence. Next, it was found that NO bioactivity and superoxide levels were unaffected in the thoracic aorta from ghrelin-deficient mice when compared with wild-type mice. Lastly, using novel GHSR-eGFP reporter mice in combination with double-labelled immunofluorescence, no evidence was found for the growth hormone secretagogue receptor (GHSR1a) in the throracic aorta, which is the only functional ghrelin receptor identified to date. Collectively these findings demonstrate that, in contrast to systemic vessels of other species (e.g. rat and human) and mouse cerebral vessels, ghrelin-related peptides do not modulate vasodilator NO production or superoxide levels in mouse systemic arteries. © 2016 John Wiley & Sons Australia, Ltd.

Lithium modulates the chronic stress-induced effect on blood glucose level of male rats

Directory of Open Access Journals (Sweden)

Popović Nataša

2010-01-01

Full Text Available In the present study we examined gross changes in the mass of whole adrenal glands and that of the adrenal cortex, as well as the serum corticosterone and glucose level of mature male Wistar rats subjected to three different treatments: animals subjected to chronic restraint-stress, animals injected with lithium (Li and chronically stressed rats treated with Li. Under all three conditions we observed hypertrophy of whole adrenals, as well as the adrenal cortices. Chronic restraint stress, solely or in combination with Li treatment, significantly elevated the corticosterone level, but did not change the blood glucose level. Animals treated only with Li exhibited an elevated serum corticosterone level and blood glucose level. The aim of our study was to investigate the modulation of the chronic stress-induced effect on the blood glucose level by lithium, as a possible mechanism of avoiding the damage caused by chronic stress. Our results showed that lithium is an agent of choice which may help to reduce stress-elevated corticosterone and replenish exhausted glucose storages in an organism.

4G/5G polymorphism modulates PAI-1 circulating levels in obese women.

Science.gov (United States)

Fernandes, Karla S; Sandrim, Valéria C

2012-05-01

The increase in plasminogen activator inhibitor type 1 (PAI-1) has been described as a risk factor to thrombosis-related diseases. In addition, it has been demonstrated that the variant 4G of polymorphism 4G/5G located in promoter region of PAI-1 gene is associated with higher PAI-1 levels. We investigate the role of this polymorphism on circulating PAI-1 concentration in a population of 57 obese women (23%, 4G/4G; 49%, 4G/5G and 28%, 5G/5G genotypes). Our results demonstrate a genotype-specific modulation on PAI-1 levels in obese women, thus 5G/5G genotype presented significantly lower levels of plasma PAI-1 when compared to 4G/4G group (46 ± 19 ng/mL vs. 63 ± 13 ng/mL, respectively). Our findings indicate that obese carriers of 4G/4G genotype may have increased risk to develop thrombotic diseases.

Synergistic effect of fluorination on molecular energy level modulation in highly efficient photovoltaic polymers.

Science.gov (United States)

Zhang, Maojie; Guo, Xia; Zhang, Shaoqing; Hou, Jianhui

2014-02-01

The synergistic effect of fluorination on molecular energy level modulation is realized by introducing fluorine atoms onto both the donor and the acceptor moieties in a D-A polymer, and as a result, the polymer solar cell device based on the trifluorinated polymer, PBT-3F, shows a high efficiency of 8.6%, under illumination of AM 1.5G, 100 mW cm(-) (2) . © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modulation of the sound press level by the treatment of polymer diaphragms through ion implantation method

International Nuclear Information System (INIS)

Yeo, Sunmog; Park, Jaewon; Lee, Hojae

2010-01-01

We present two different surface modification treatments, an ion implantation, and an ion beam mixing, and show that the surface modifications caused by these treatments are useful tools to modulate the sound press level. The ion implantations on various polymer diaphragms cause an increase in the resonant frequency so that the sound press level is lowered at low frequencies. On the contrary, a Cu or Fe 2 O 3 coating by using an ion beam mixing method causes a decrease in the resonant frequency, resulting in a high sound press level at low frequencies. We discuss the physical reasons for the change in the sound press level due to the ion-implantation methods.

Structural modulation of brain development by oxygen: evidence on adolescents migrating from high altitude to sea level environment.

Science.gov (United States)

Zhang, Jiaxing; Zhang, Haiyan; Chen, Ji; Fan, Ming; Gong, Qiyong

2013-01-01

The present study aimed to investigate structural modulation of brain by high level of oxygen during its peak period of development. Voxel-based morphometry analysis of gray matter (GM) and white matter (WM) volumes and Tract-Based Spatial Statistics analysis of WM fractional anisotropy (FA) and mean diffusion (MD) based on MRI images were carried out on 21 Tibetan adolencents (15-18 years), who were born and raised in Qinghai-Tibetan Plateau (2900-4700 m) and have lived at sea level (SL) in the last 4 years. The control group consisted of matched Tibetan adolescents born and raised at high altitude all the time. SL immigrants had increased GM volume in the left insula, left inferior parietal gyrus, and right superior parietal gyrus and decreased GM in the left precentral cortex and multiple sites in cerebellar cortex (left lobule 8, bilateral lobule 6 and crus 1/2). Decreased WM volume was found in the right superior frontal gyrus in SL immigrants. SL immigrants had higher FA and lower MD at multiple sites of WM tracts. Moreover, we detected changes in ventilation and circulation. GM volume in cerebellum lobule 8 positively correlated with diastolic pressure, while GM volume in insula positively correlated vital capacity and hypoxic ventilatory response. Our finding indicate that the structural modulations of GM by high level of oxygen during its peak period of development are related to respiratory and circulatory regulations, while the modulation in WM mainly exhibits an enhancement in myelin maturation.

Rate modulation detection thresholds for cochlear implant users.

Science.gov (United States)

Brochier, Tim; McKay, Colette; McDermott, Hugh

2018-02-01

The perception of temporal amplitude modulations is critical for speech understanding by cochlear implant (CI) users. The present study compared the ability of CI users to detect sinusoidal modulations of the electrical stimulation rate and current level, at different presentation levels (80% and 40% of the dynamic range) and modulation frequencies (10 and 100 Hz). Rate modulation detection thresholds (RMDTs) and amplitude modulation detection thresholds (AMDTs) were measured and compared to assess whether there was a perceptual advantage to either modulation method. Both RMDTs and AMDTs improved with increasing presentation level and decreasing modulation frequency. RMDTs and AMDTs were correlated, indicating that a common processing mechanism may underlie the perception of rate modulation and amplitude modulation, or that some subject-dependent factors affect both types of modulation detection.

Modulation of ROS levels in fibroblasts by altering mitochondria regulates the process of wound healing.

Science.gov (United States)

Janda, Jaroslav; Nfonsam, Valentine; Calienes, Fernanda; Sligh, James E; Jandova, Jana

2016-05-01

Mitochondria are the major source of reactive oxygen species (ROS) in fibroblasts which are thought to be crucial regulators of wound healing with a potential to affect the expression of nuclear genes involved in this process. ROS generated by mitochondria are involved in all stages of tissue repair process but the regulation of ROS-generating system in fibroblasts still remains poorly understood. The purpose of this study was to better understand molecular mechanisms of how the regulation of ROS levels generated by mitochondria may influence the process of wound repair. Cybrid model system of mtDNA variations was used to study the functional consequences of altered ROS levels on wound healing responses in a uniform nuclear background of cultured ρ(0) fibroblasts. Mitochondrial ROS in cybrids were modulated by antioxidants that quench ROS to examine their ability to close the wound. Real-time PCR arrays were used to investigate whether ROS generated by specific mtDNA variants have the ability to alter expression of some key nuclear-encoded genes central to the wound healing response and oxidative stress. Our data suggest levels of mitochondrial ROS affect expression of some nuclear encoded genes central to wound healing response and oxidative stress and modulation of mitochondrial ROS by antioxidants positively affects in vitro process of wound closure. Thus, regulation of mitochondrial ROS-generating system in fibroblasts can be used as effective natural redox-based strategy to help treat non-healing wounds.

Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

International Nuclear Information System (INIS)

Saphier, D.

1978-09-01

The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

Two-level modulation scheme to reduce latency for optical mobile fronthaul networks.

Science.gov (United States)

Sung, Jiun-Yu; Chow, Chi-Wai; Yeh, Chien-Hung; Chang, Gee-Kung

2016-10-31

A system using optical two-level orthogonal-frequency-division-multiplexing (OFDM) - amplitude-shift-keying (ASK) modulation is proposed and demonstrated to reduce the processing latency for the optical mobile fronthaul networks. At the proposed remote-radio-head (RRH), the high data rate OFDM signal does not need to be processed, but is directly launched into a high speed photodiode (HSPD) and subsequently emitted by an antenna. Only a low bandwidth PD is needed to recover the low data rate ASK control signal. Hence, it is simple and provides low-latency. Furthermore, transporting the proposed system over the already deployed optical-distribution-networks (ODNs) of passive-optical-networks (PONs) is also demonstrated with 256 ODN split-ratios.

Open-Source Python Modules to Estimate Level Ice Thickness from Ice Charts

Science.gov (United States)

Geiger, C. A.; Deliberty, T. L.; Bernstein, E. R.; Helfrich, S.

2012-12-01

A collaborative research effort between the University of Delaware (UD) and National Ice Center (NIC) addresses the task of providing open-source translations of sea ice stage-of-development into level ice thickness estimates on a 4km grid for the Interactive Multisensor Snow and Ice Mapping System (IMS). The characteristics for stage-of-development are quantified from remote sensing imagery with estimates of level ice thickness categories originating from World Meteorological Organization (WMO) egg coded ice charts codified since the 1970s. Conversions utilize Python scripting modules which transform electronic ice charts with WMO egg code characteristics into five level ice thickness categories, in centimeters, (0-10, 10-30, 30-70, 70-120, >120cm) and five ice types (open water, first year pack ice, fast ice, multiyear ice, and glacial ice with a reserve slot for deformed ice fractions). Both level ice thickness categories and ice concentration fractions are reported with uncertainties propagated based on WMO ice stage ranges which serve as proxy estimates for standard deviation. These products are in preparation for use by NCEP, CMC, and NAVO by 2014 based on their modeling requirements for daily products in near-real time. In addition to development, continuing research tests the value of these estimated products against in situ observations to improve both value and uncertainty estimates.

Enhanced susceptibility to seizures modulated by high interleukin-1β levels during early life malnutrition.

Science.gov (United States)

Simão, Fabrício; Habekost Oliveira, Victória; Lahorgue Nunes, Magda

2016-10-01

Early malnutrition in life has permanent consequences on brain development and has been suggested to influence seizure susceptibility. Despite malnutrition is not a direct cause of seizures, we hypothesize that malnutrition may modulate inflammatory response and result in cerebral vulnerability to seizures. In this study, we provide evidence that malnutrition may increase susceptibility to seizures in the postnatal period by interleukin-1β (IL-1β) in the hippocampus. Malnourished rats were maintained on a nutritional deprivation regimen from postnatal day 1 (P1) to P10. From P7 to P10, the threshold to seizures induced by flurothyl was used as an index of seizure susceptibility. ELISA and western blot was performed to evaluate levels of IL-1β, IL-1R1, PSD-95 and synapsin. The role of inflammation in the changes of seizure threshold was studied with inhibitors of IL-1β and IL-1R1. A significant decrease in body weight and seizure threshold was observed in postnatal malnourished rats. Early malnutrition modulates inflammation by high levels of IL-1β in hippocampus and in serum. Furthermore, our malnutrition paradigm induced an increase in corticosterone levels. Injection of IL-1β and IL-1R1 inhibitors before seizure induction augments seizure threshold in malnourished rats similar to nourished group. Malnutrition did not change PSD-95 and synapsin expression in the hippocampus. We suggest that malnutrition-induced inflammation might contribute to seizure susceptibility in the postnatal period. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1150-1159, 2016. © 2016 Wiley Periodicals, Inc.

Mitochondrial DNA levels in Huntington disease leukocytes and dermal fibroblasts.

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Jędrak, Paulina; Krygier, Magdalena; Tońska, Katarzyna; Drozd, Małgorzata; Kaliszewska, Magdalena; Bartnik, Ewa; Sołtan, Witold; Sitek, Emilia J; Stanisławska-Sachadyn, Anna; Limon, Janusz; Sławek, Jarosław; Węgrzyn, Grzegorz; Barańska, Sylwia

2017-08-01

Huntington disease (HD) is an inherited neurodegenerative disorder caused by mutations in the huntingtin gene. Involvement of mitochondrial dysfunctions in, and especially influence of the level of mitochondrial DNA (mtDNA) on, development of this disease is unclear. Here, samples of blood from 84 HD patients and 79 controls, and dermal fibroblasts from 10 HD patients and 9 controls were analysed for mtDNA levels. Although the type of mitochondrial haplogroup had no influence on the mtDNA level, and there was no correlation between mtDNA level in leukocytes in HD patients and various parameters of HD severity, some considerable differences between HD patients and controls were identified. The average mtDNA/nDNA relative copy number was significantly higher in leukocytes, but lower in fibroblasts, of symptomatic HD patients relative to the control group. Moreover, HD women displayed higher mtDNA levels in leukocytes than HD men. Because this is the largest population analysed to date, these results might contribute to explanation of discrepancies between previously published studies concerning levels of mtDNA in cells of HD patients. We suggest that the size of the investigated population and type of cells from which DNA is isolated could significantly affect results of mtDNA copy number estimation in HD. Hence, these parameters should be taken into consideration in studies on mtDNA in HD, and perhaps also in other diseases where mitochondrial dysfunction occurs.

ANALYSIS OF HARMONIC INJECTION TO THE MODULATION OF ...

African Journals Online (AJOL)

2013-03-01

Mar 1, 2013 ... Abstract. This paper explores the analysis of third and ninth harmonic injection to the modulation of a multi- level diode clamped converter (DCC) at a varying modulation index. The spectral distributions of the various multi-level waveforms obtained under normal modulation index of 0.8 and over modulation ...

Low-cost solar module manufacturing

International Nuclear Information System (INIS)

Little, Roger G.; Nowlan, Michael J.; Matthei, Keith W.; Darkazalli, Ghazi

1997-01-01

As the market for terrestrial photovoltaic modules expands beyond the 80 MW per year level, module manufacturers are adopting a number of cost-reduction strategies, including the use of higher throughput equipment, increased process automation, and the fabrication of larger area cells and modules. This paper reviews recent activities at Spire Corporation in the development of advanced module manufacturing and testing equipment

Three-Level Inverters with Common-Mode Voltage Cancellation Based on Synchronous Pulsewidth Modulation

DEFF Research Database (Denmark)

Oleschuk, Valentin; Blaabjerg, Frede

2002-01-01

A novel method of direct synchronous pulse-width modulation (PWM) is disseminated to three-level voltage source inverters with control algorithms with elimination of the common-mode voltages in three-phase drive systems with PWM. It provides smooth pulses-ratio changing and a quarter-wave symmetry...... of the voltage waveforms during the whole control range including overmodulation. Continuous, discontinuous and "direct-direct" schemes of synchronous PWM with both algebraic and trigonometric control functions have been analysed and compared. Simulations give the behaviour of the proposed methods and show some...... advantages of synchronous PWM in comparison with asynchronous at low ratios between the switching frequency and fundamental frequency....

Periodically Swapping Modulation (PSM) Strategy for Three-Level (TL) DC/DC Converter with Balanced Switch Currents

DEFF Research Database (Denmark)

Liu, Dong; Deng, Fujin; Zhang, Qi

2018-01-01

The asymmetrical modulation strategy is widely used in various types of three-level (TL) DC/DC converters, while the current imbalance among the power switches is one of the important issues. In this paper, a novel periodically swapping modulation (PSM) strategy is proposed for balancing the power...... switches’ currents in various types of TL DC/DC converters. In the proposed PSM strategy, the driving signals of the switch pairs are swapped periodically, which guarantees that the currents through the power switches are kept balanced in every two switching periods. Therefore, the proposed PSM...... strategy can effectively improve the reliability of the converter by balancing the power losses and thermal stresses among the power switches. The operation principle and performances of the proposed PSM strategy are analyzed in detail. Finally, the simulation and experimental results are presented...

A series of N-terminal epitope tagged Hdh knock-in alleles expressing normal and mutant huntingtin: their application to understanding the effect of increasing the length of normal huntingtin’s polyglutamine stretch on CAG140 mouse model pathogenesis

Directory of Open Access Journals (Sweden)

Zheng Shuqiu

2012-08-01

Full Text Available Abstract Background Huntington’s disease (HD is an autosomal dominant neurodegenerative disease that is caused by the expansion of a polyglutamine (polyQ stretch within Huntingtin (htt, the protein product of the HD gene. Although studies in vitro have suggested that the mutant htt can act in a potentially dominant negative fashion by sequestering wild-type htt into insoluble protein aggregates, the role of the length of the normal htt polyQ stretch, and the adjacent proline-rich region (PRR in modulating HD mouse model pathogenesis is currently unknown. Results We describe the generation and characterization of a series of knock-in HD mouse models that express versions of the mouse HD gene (Hdh encoding N-terminal hemaglutinin (HA or 3xFlag epitope tagged full-length htt with different polyQ lengths (HA7Q-, 3xFlag7Q-, 3xFlag20Q-, and 3xFlag140Q-htt and substitution of the adjacent mouse PRR with the human PRR (3xFlag20Q- and 3xFlag140Q-htt. Using co-immunoprecipitation and immunohistochemistry analyses, we detect no significant interaction between soluble full-length normal 7Q- htt and mutant (140Q htt, but we do observe N-terminal fragments of epitope-tagged normal htt in mutant htt aggregates. When the sequences encoding normal mouse htt’s polyQ stretch and PRR are replaced with non-pathogenic human sequence in mice also expressing 140Q-htt, aggregation foci within the striatum, and the mean size of htt inclusions are increased, along with an increase in striatal lipofuscin and gliosis. Conclusion In mice, soluble full-length normal and mutant htt are predominantly monomeric. In heterozygous knock-in HD mouse models, substituting the normal mouse polyQ and PRR with normal human sequence can exacerbate some neuropathological phenotypes.

Measuring high-frequency responses of an electro-optic phase modulator based on dispersion induced phase modulation to intensity modulation conversion

Science.gov (United States)

Zhang, Shangjian; Wang, Heng; Wang, Yani; Zou, Xinhai; Zhang, Yali; Liu, Shuang; Liu, Yong

2014-11-01

We investigate the phase modulation to intensity modulation conversion in dispersive fibers for measuring frequency responses of electro-optic phase modulators, and demonstrate two typical measurements with cascade path and fold-back path. The measured results achieve an uncertainty of less than 2.8% within 20 GHz. Our measurements show stable and repeatable results because the optical carrier and its phase-modulated sidebands are affected by the same fiber impairments. The proposed method requires only dispersive fibers and works without any small-signal assumption, which is applicable for swept frequency measurement at different driving levels and operating wavelengths.

Huntingtin-Interacting Protein 1-Related Protein Plays a Critical Role in Dendritic Development and Excitatory Synapse Formation in Hippocampal Neurons

Directory of Open Access Journals (Sweden)

Lin Peng

2017-06-01

Full Text Available Huntingtin-interacting protein 1-related (HIP1R protein is considered to be an endocytic adaptor protein like the other two members of the Sla2 family, Sla2p and HIP1. They all contain homology domains responsible for the binding of clathrin, inositol lipids and F-actin. Previous studies have revealed that HIP1R is highly expressed in different regions of the mouse brain and localizes at synaptic structures. However, the function of HIP1R in the nervous system remains unknown. In this study, we investigated HIP1R function in cultured rat hippocampal neurons using an shRNA knockdown approach. We found that, after HIP1R knockdown, the dynamics and density of dendritic filopodia, and dendritic branching and complexity were significantly reduced in developing neurons, as well as the densities of dendritic spines and PSD95 clusters in mature neurons. Moreover, HIP1R deficiency led to significantly reduced expression of the ionotropic glutamate receptor GluA1, GluN2A and GluN2B subunits, but not the GABAA receptor α1 subunit. Similarly, HIP1R knockdown reduced the amplitude and frequency of the miniature excitatory postsynaptic current, but not of the miniature inhibitory postsynaptic current. In addition, the C-terminal proline-rich region of HIP1R responsible for cortactin binding was found to confer a dominant-negative effect on dendritic branching in cultured developing neurons, implying a critical role of cortactin binding in HIP1R function. Taken together, the results of our study suggest that HIP1R plays important roles in dendritic development and excitatory synapse formation and function.

Health Occupations Module. The Integumentary System.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on the integumentary system is one of eight modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module contains an introduction to the module topic, objectives (e.g., list and describe the types of glands formed in the skin, and explain the…

A photovoltaic module

DEFF Research Database (Denmark)

2013-01-01

The present invention relates to a photovoltaic module comprising a carrier substrate, said carrier substrate carrying a purely printed structure comprising printed positive and negative module terminals, a plurality of printed photovoltaic cell units each comprising one or more printed...... photovoltaic cells, wherein the plurality of printed photovoltaic cell units are electrically connected in series between the positive and the negative module terminals such that any two neighbouring photovoltaic cell units are electrically connected by a printed interconnecting electrical conductor....... The carrier substrate comprises a foil and the total thickness of the photovoltaic module is below 500 [mu]m. Moreover, the nominal voltage level between the positive and the negative terminals is at least 5 kV DC....

Clues to γ-secretase, huntingtin and Hirano body normal function using the model organism Dictyostelium discoideum

Directory of Open Access Journals (Sweden)

Myre Michael A

2012-04-01

Full Text Available Abstract Many neurodegenerative disorders, although related by their destruction of brain function, display remarkable cellular and/or regional pathogenic specificity likely due to a deregulated functionality of the mutant protein. However, neurodegenerative disease genes, for example huntingtin (HTT, the ataxins, the presenilins (PSEN1/PSEN2 are not simply localized to neurons but are ubiquitously expressed throughout peripheral tissues; it is therefore paramount to properly understand the earliest precipitating events leading to neuronal pathogenesis to develop effective long-term therapies. This means, in no unequivocal terms, it is crucial to understand the gene's normal function. Unfortunately, many genes are often essential for embryogenesis which precludes their study in whole organisms. This is true for HTT, the β-amyloid precursor protein (APP and presenilins, responsible for early onset Alzheimer's disease (AD. To better understand neurological disease in humans, many lower and higher eukaryotic models have been established. So the question arises: how reasonable is the use of organisms to study neurological disorders when the model of choice does not contain neurons? Here we will review the surprising, and novel emerging use of the model organism Dictyostelium discoideum, a species of soil-living amoeba, as a valuable biomedical tool to study the normal function of neurodegenerative genes. Historically, the evidence on the usefulness of simple organisms to understand the etiology of cellular pathology cannot be denied. But using an organism without a central nervous system to understand diseases of the brain? We will first introduce the life cycle of Dictyostelium, the presence of many disease genes in the genome and how it has provided unique opportunities to identify mechanisms of disease involving actin pathologies, mitochondrial disease, human lysosomal and trafficking disorders and host-pathogen interactions. Secondly, I will

Folding Landscape of Mutant Huntingtin Exon1: Diffusible Multimers, Oligomers and Fibrils, and No Detectable Monomer.

Directory of Open Access Journals (Sweden)

Bankanidhi Sahoo

Full Text Available Expansion of the polyglutamine (polyQ track of the Huntingtin (HTT protein above 36 is associated with a sharply enhanced risk of Huntington's disease (HD. Although there is general agreement that HTT toxicity resides primarily in N-terminal fragments such as the HTT exon1 protein, there is no consensus on the nature of the physical states of HTT exon1 that are induced by polyQ expansion, nor on which of these states might be responsible for toxicity. One hypothesis is that polyQ expansion induces an alternative, toxic conformation in the HTT exon1 monomer. Alternative hypotheses posit that the toxic species is one of several possible aggregated states. Defining the nature of the toxic species is particularly challenging because of facile interconversion between physical states as well as challenges to identifying these states, especially in vivo. Here we describe the use of fluorescence correlation spectroscopy (FCS to characterize the detailed time and repeat length dependent self-association of HTT exon1-like fragments both with chemically synthesized peptides in vitro and with cell-produced proteins in extracts and in living cells. We find that, in vitro, mutant HTT exon1 peptides engage in polyQ repeat length dependent dimer and tetramer formation, followed by time dependent formation of diffusible spherical and fibrillar oligomers and finally by larger, sedimentable amyloid fibrils. For expanded polyQ HTT exon1 expressed in PC12 cells, monomers are absent, with tetramers being the smallest molecular form detected, followed in the incubation time course by small, diffusible aggregates at 6-9 hours and larger, sedimentable aggregates that begin to build up at 12 hrs. In these cell cultures, significant nuclear DNA damage appears by 6 hours, followed at later times by caspase 3 induction, mitochondrial dysfunction, and cell death. Our data thus defines limits on the sizes and concentrations of different physical states of HTT exon1 along the

High fat diet and inflammation - modulation of Haptoglobin level in rat brain

Directory of Open Access Journals (Sweden)

Maria Stefania eSpagnuolo

2015-12-01

Full Text Available Obesity and dietary fats are well known risk factors for the pathogenesis of neurodegenerative diseases. The analysis of specific markers, whose brain level can be affected by diet, might contribute to unveil the intersection between inflammation/obesity and neurodegeneration. Haptoglobin (Hpt is an acute phase protein, which acts as antioxidant by binding free Haemoglobin (Hb, thus neutralizing its pro-oxidative action. We previously demonstrated that Hpt plays critical functions in brain, modulating cholesterol trafficking in neuroblastoma cell lines, beta-amyloid (Aβ uptake by astrocyte, and limiting Aβ toxicity on these cells. A major aim of this study was to evaluate whether a long term (12 or 24 weeks high-fat diet (HFD influences Hpt and Hb expression in rat hippocampus. We also assessed the development of obesity-induced inflammation by measuring hippocampal level of TNF-alpha, and the extent of protein oxidation by titrating nitro-tyrosine (N-Tyr. Hpt concentration was lower (p<0.001 in hippocampus of HFD rats than in control animals, both in the 12 and in the 24 weeks fed groups. HFD was also associated in hippocampus with the increase of Hb level (p<0.01, inflammation and protein oxidative modification, as evidenced by the increase in the concentration of TNF-alpha and nitro-tyrosine. In fact, TNF-alpha concentration was higher in rats receiving HFD for 12 (p<0.01 or 24 weeks (p<0.001 compared to those receiving the control diet. N-Tyr concentration was more elevated in hippocampus of HFD than in control rats in both 12 weeks (p=0.04 and 24 weeks groups (p=0.01, and a positive correlation between Hb and N-Tyr concentration was found in each group. Finally, we found that the treatment of the human glioblastoma-astrocytoma cell line U-87 MG with cholesterol and fatty acids, such as palmitic and linoleic acid, significantly impairs (p<0.001 Hpt secretion in the extracellular compartment.We hypothesize that the HFD-dependent decrease of

Receiver bandwidth effects on complex modulation and detection using directly modulated lasers.

Science.gov (United States)

Yuan, Feng; Che, Di; Shieh, William

2016-05-01

Directly modulated lasers (DMLs) have long been employed for short- and medium-reach optical communications due to their low cost. Recently, a new modulation scheme called complex modulated DMLs has been demonstrated showing a significant optical signal to noise ratio sensitivity enhancement compared with the traditional intensity-only detection scheme. However, chirp-induced optical spectrum broadening is inevitable in complex modulated systems, which may imply a need for high-bandwidth receivers. In this Letter, we study the impact of receiver bandwidth effects on the performance of complex modulation and coherent detection systems based on DMLs. We experimentally demonstrate that such systems exhibit a reasonable tolerance for the reduced receiver bandwidth. For 10 Gbaud 4-level pulse amplitude modulation signals, the required electrical bandwidth is as low as 8.5 and 7.5 GHz for 7% and 20% forward error correction, respectively. Therefore, it is feasible to realize DML-based complex modulated systems using cost-effective receivers with narrow bandwidth.

Characterization of the Transient Response of the ILS with One Module Installed to Heatup Changes in Power Level and Cooldown

International Nuclear Information System (INIS)

K. G. Condie; C. M. Stoots; J. E. O'Brien; J. S. Herring

2007-01-01

This report provides documentation of the initial startup and testing of the first electrolysis module in the Idaho National Laboratory (INL) High Temperature Steam Electrolysis Integrated Laboratory Scale (ILS) facility. Initial shakedown testing of the INL ILS experimental facility commenced on August 22, 2007. This fulfilled a DOE Level 2 milestone. Heatup of the first ILS module started at approximately 4:10 PM on September 24, 2007. Initial module testing continued for 420 hours. The test average H2 production rate was approximately 1.3 Nm3/hr (0.116 kg H2/hr), with a peak measured value of over 2 Nm3/hr (0.179 kg H2/hr). Significant module performance degradation was observed over the first 250 hours, after which no further degradation was noted for the remainder of the test. Once all test objectives had been successfully met, the test was terminated in a controlled fashion. Discussion is included concerning several modifications that will be incorporated into the facility components to improve reliability and ease of operation for future long term testing

Periodically modulated dark states

Science.gov (United States)

Han, Yingying; Zhang, Jun; Zhang, Wenxian

2018-04-01

Phenomena of electromagnetically induced transparency (PEIT) may be interpreted by the Autler-Townes Splitting (ATS), where the coupled states are split by the coupling laser field, or by the quantum destructive interference (QDI), where the atomic phases caused by the coupling laser and the probe laser field cancel. We propose modulated experiments to explore the PEIT in an alternative way by periodically modulating the coupling and the probe fields in a Λ-type three-level system initially in a dark state. Our analytical and numerical results rule out the ATS interpretation and show that the QDI interpretation is more appropriate for the modulated experiments. Interestingly, dark state persists in the double-modulation situation where control and probe fields never occur simultaneously, which is significant difference from the traditional dark state condition. The proposed experiments are readily implemented in atomic gases, artificial atoms in superconducting quantum devices, or three-level meta-atoms in meta-materials.

[Plasma IL-18 levels are related to insulin and are modulated by IL-18 gene polymorphisms].

Science.gov (United States)

Martinez-Hervas, Sergio; Martínez-Barquero, Vanesa; Nuñez Savall, Ester; Lendínez, Verónica; Olivares, Laura; Benito, Esther; Real, Jose T; Chaves, F Javier; Ascaso, Juan F

2015-01-01

Atherosclerosis is an inflammatory chronic disease influenced by multiple factors. Different prospective studies have shown that plasmatic levels of inflammatory markers were related to atherosclerosis and cardiovascular disease. To evaluate whether plasmatic levels of interleukin 18 (IL-18) are modulated by SNPs (single nucleotide polymorphisms) of the IL 18 gene and its possible association with insulin levels and other cardiovascular risk factors. 746 individuals were studied for a period of two years by opportunistic selection in the metropolitan area of Valencia. Parameters of lipid and glucose metabolism were analyzed by standard methodology. IL-18 was measured by ELISA. Individuals with insulin resistance showed significant higher levels of IL-18. IL 18 was significantly correlated with insulin levels and other cardiovascular risk factors. The CC genotype of the rs1834481 SNP was significantly associated with lower levels of IL-18. However, the GG genotype of the rs7559479 was associated with significant higher levels of IL-18. IL-18 is associated with insulin resistance and other cardiovascular risk factors, being those levels genetically regulated. Copyright © 2015 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

Synchronised Voltage Space Vector Modulation for Three-level Inverters with Common-mode Voltage Elimination

DEFF Research Database (Denmark)

Oleschuk, Valentin; Blaabjerg, Frede

2002-01-01

A novel method of direct synchronous pulse-width modulation (PWM) is disseminated to three-level voltage source inverters with control algorithms with elimination of the common-mode voltages in three-phase drive systems with PWM. It provides smooth pulses-ratio changing and a quarter-wave symmetry...... of the voltage waveforms during the whole control range including overmodulation. Continuous, discontinuous and "direct-direct" schemes of synchronous PWM with both algebraic and trigonometric control functions have been analysed and compared. Simulations give the behaviour of the proposed methods and show some...... advantages of synchronous PWM in comparison with asynchronous at low ratios between the switching frequency and fundamental frequency....

The importance of macro- versus microstructure in modulating light levels inside coral colonies

DEFF Research Database (Denmark)

Kaniewska, Paulina; Magnusson, Sveinn H.; Anthony, Ken R. N.

2011-01-01

Adjusting the light exposure and capture of their symbiotic photosynthetic dinoflagellates (genus Symbiodinium Freud.) is central to the success of reef-building corals (order Scleractinia) across high spatio-temporal variation in the light environment of coral reefs. We tested the hypothesis...... irradiances at the level of coral photosymbionts. Key index words: irradiance; morphology; photoacclimation; scale; scleractinian coral; Symbiodinium Abbreviations: a chl a, specific absorption coefficient of chl a; Ddn, diadinoxanthin; Dtn, diatoxanthin; GBR, Great Barrier Reef; GFP, green fluorescent...... that optical properties of tissues in some coral species can provide light management at the tissue scale comparable to light modulation by colony architecture in other species. We compared within-tissue scalar irradiance in two coral species from the same light habitat but with contrasting colony growth forms...

2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint

Energy Technology Data Exchange (ETDEWEB)

Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

2014-11-01

A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

Medical Terminology: Suffixes. Health Occupations Education Module.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on medical terminology (suffixes) is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module consists of an introduction to the module topic, a list of resources needed, and three learning experiences. The first two learning…

Health Occupations Module. The Skeletal System--I.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on the skeletal system is one of eight modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module contains an introduction to the module topic, three objectives (e.g., define the skeletal system and list its functions), and three learning…

Fashion Merchandising Module. An Advanced-Level Option for Distribution and Marketing. For the U.S.O.E. Occupational Cluster of 04.02 Apparel and Accessories Marketing.

Science.gov (United States)

Clis, Pat; And Others

This instructional module on fashion merchandising is designed as a guide for secondary education teachers who are helping twelfth grade students develop occupational competency for entry-level positions in fashion-related jobs. An introductory section covers module goals, career opportunities and employment demands, administrative considerations,…

Health Occupations Module. The Skeletal System--II.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on the skeletal system is one of eight modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module contains an introduction to the module topic, two objectives (e.g., list the types of joints and movements, and give examples), and two learning…

Effect of modulated ultrahigh frequency field on behavior and hormone level in female rats under emotional stress

Energy Technology Data Exchange (ETDEWEB)

Rasulov, M.M.

The effect of a modulated electromagnetic field (MEMF) (field frequency of 40 MHz and modulated frequency of 50 Hz, 1 h exposure daily for 30 days) on behavior and level of sexual hormones, determined from the length of the estrous cycle and of its separate phases, was studied in female Wistar rats subjected to sexual deprivation. The ratio of frequency of running to number of vertical positions (R:V) was used as an index. Activity of rats declined during the 1-h exposure to MEMF; this may indicate the direct effect of MEMF on the central nervous system. Analysis of behavior after MEMF treatments ceased showed that the R:V ratio increased from 3.2:1 to 3:1 in month 3 and reached 2:1 in month 5. The relative significance of sexual behavior (lordosis, licking of perineum) more than double in comparison with the initial level. The findings support the existence of individual differences in sensitivity to a UHF field. The data on the estrous cycle indicate the tranquilizing effect of a UHF field on the neuroendocrine system and the greater resistance of individual animals exposed to MEMF to the development of sexual neurosis. 12 references, 2 figures.

Direct RF modulation transmitter, sampling clock frequency setting method for direct RF modulation transmitter

NARCIS (Netherlands)

Fukuda, Shuichi; Nauta, Bram

2013-01-01

PROBLEM TO BE SOLVED: To provide a direct RF modulation transmitter capable of satisfying a radiation level regulation even without providing a SAW filter. SOLUTION: A direct RF modulation transmitter includes: digital/RF converters 105, 106 to which an I digital baseband signal, a Q digital

Direct RF modulation transmitter, sampling clock frequency setting method for direct RF modulation transmitter

NARCIS (Netherlands)

Fukuda, Shuichi; Nauta, Bram

2014-01-01

PROBLEM TO BE SOLVED: To provide a direct RF modulation transmitter capable of satisfying a radiation level regulation even without providing a SAW filter. SOLUTION: A direct RF modulation transmitter includes: digital/RF converters 105, 106 to which an I digital baseband signal, a Q digital

Module-Integrated Power Converters Based on Universal Dock

Energy Technology Data Exchange (ETDEWEB)

Chapman, Patrick; Rodriguez, Fernando

2015-03-13

Solar power installations using alternating current photovoltaic (ACPV) modules have significant cost and performance advantages over systems using conventional solar modules and string inverters. ACPV modules have improved energy harvest due to module-level power point tracking and redundancy. More importantly, ACPV modules are easier and cheaper to install, lowering the total installed cost, indirect costs, and barriers to market entry. Furthermore, ACPV modules have communications and data logging capability, yielding module-level telemetry data that is useful in site diagnostics and other data applications. The products of these efforts were threefold. First, an advanced microinverter power topology was developed, modeled, simulated, and tested. Second, new microinverter enclosure concepts were developed and tested. Third, a new ACPV module prototype was constructed, combining the power topology and the enclosure concepts. SolarBridge filed for patents in each of these areas and is transitioning the project from a concept phase to full development.

γ-Secretase modulators reduce endogenous amyloid β42 levels in human neural progenitor cells without altering neuronal differentiation

Science.gov (United States)

D’Avanzo, Carla; Sliwinski, Christopher; Wagner, Steven L.; Tanzi, Rudolph E.; Kim, Doo Yeon; Kovacs, Dora M.

2015-01-01

Soluble γ-secretase modulators (SGSMs) selectively decrease toxic amyloid β (Aβ) peptides (Aβ42). However, their effect on the physiologic functions of γ-secretase has not been tested in human model systems. γ-Secretase regulates fate determination of neural progenitor cells. Thus, we studied the impact of SGSMs on the neuronal differentiation of ReNcell VM (ReN) human neural progenitor cells (hNPCs). Quantitative PCR analysis showed that treatment of neurosphere-like ReN cell aggregate cultures with γ-secretase inhibitors (GSIs), but not SGSMs, induced a 2- to 4-fold increase in the expression of the neuronal markers Tuj1 and doublecortin. GSI treatment also induced neuronal marker protein expression, as shown by Western blot analysis. In the same conditions, SGSM treatment selectively reduced endogenous Aβ42 levels by ∼80%. Mechanistically, we found that Notch target gene expressions were selectively inhibited by a GSI, not by SGSM treatment. We can assert, for the first time, that SGSMs do not affect the neuronal differentiation of hNPCs while selectively decreasing endogenous Aβ42 levels in the same conditions. Our results suggest that our hNPC differentiation system can serve as a useful model to test the impact of GSIs and SGSMs on both endogenous Aβ levels and γ-secretase physiologic functions including endogenous Notch signaling.—D’Avanzo, C., Sliwinski, C., Wagner, S. L., Tanzi, R. E., Kim, D. Y., Kovacs, D. M. γ-Secretase modulators reduce endogenous amyloid β42 levels in human neural progenitor cells without altering neuronal differentiation. PMID:25903103

Activation of IGF-1 and insulin signaling pathways ameliorate mitochondrial function and energy metabolism in Huntington's Disease human lymphoblasts.

Science.gov (United States)

Naia, Luana; Ferreira, I Luísa; Cunha-Oliveira, Teresa; Duarte, Ana I; Ribeiro, Márcio; Rosenstock, Tatiana R; Laço, Mário N; Ribeiro, Maria J; Oliveira, Catarina R; Saudou, Frédéric; Humbert, Sandrine; Rego, A Cristina

2015-02-01

Huntington's disease (HD) is an inherited neurodegenerative disease caused by a polyglutamine repeat expansion in the huntingtin protein. Mitochondrial dysfunction associated with energy failure plays an important role in this untreated pathology. In the present work, we used lymphoblasts obtained from HD patients or unaffected parentally related individuals to study the protective role of insulin-like growth factor 1 (IGF-1) versus insulin (at low nM) on signaling and metabolic and mitochondrial functions. Deregulation of intracellular signaling pathways linked to activation of insulin and IGF-1 receptors (IR,IGF-1R), Akt, and ERK was largely restored by IGF-1 and, at a less extent, by insulin in HD human lymphoblasts. Importantly, both neurotrophic factors stimulated huntingtin phosphorylation at Ser421 in HD cells. IGF-1 and insulin also rescued energy levels in HD peripheral cells, as evaluated by increased ATP and phosphocreatine, and decreased lactate levels. Moreover, IGF-1 effectively ameliorated O2 consumption and mitochondrial membrane potential (Δψm) in HD lymphoblasts, which occurred concomitantly with increased levels of cytochrome c. Indeed, constitutive phosphorylation of huntingtin was able to restore the Δψm in lymphoblasts expressing an abnormal expansion of polyglutamines. HD lymphoblasts further exhibited increased intracellular Ca(2+) levels before and after exposure to hydrogen peroxide (H2O2), and decreased mitochondrial Ca(2+) accumulation, being the later recovered by IGF-1 and insulin in HD lymphoblasts pre-exposed to H2O2. In summary, the data support an important role for IR/IGF-1R mediated activation of signaling pathways and improved mitochondrial and metabolic function in HD human lymphoblasts.

The role of the habenula-interpeduncular pathway in modulating levels of circulating adrenal hormones.

Science.gov (United States)

Murray, M; Murphy, C A; Ross, L L; Haun, F

1994-01-01

The fasciculus retroflexus (FR) is the major pathway by which the medial and lateral habenular nuclei project to the interpeduncular nucleus (IPN) and ventral tegmentum. Recent work has suggested that the habenula-interpeduncular system may be involved in the regulation of states of arousal. Bilateral FR lesions have been shown to disrupt chronically, and habenula transplants have been shown to restore normal sleep patterns in rats [J. NeuroscL, 12 (1992) 3282-3290]. In this study, we examined whether FR lesions and habenula cell transplants would also modify chronically the circulating plasma levels of the stress-related hormones, norepinephrine (NE), epinephrine (EPI) and corticosterone. When plasma samples were obtained via retro-orbital eye-bleed during anesthesia, animals with FR lesions had significantly increased levels of plasma NE, EPI and corticosterone 2-3 months postoperatively compared to unoperated controls. Transplants of embryonic habenula cells placed near the denervated IPN in FR-lesioned animals restored levels of NE and EPI to normal, but did not attenuate elevated corticosterone levels. When plasma samples were obtained in conscious animals via indwelling arterial cannulae, FR-lesioned rats likewise exhibited increased basal levels of corticosterone but plasma levels of catecholamines were similar to those of unoperated controls. Differences in our results obtained using the two methods of blood sampling may be explained by the effects of anesthesia and stress associated with the eye-bleed method. Thus, the effect of FR lesions in increasing plasma levels of catecholamines may not reflect a difference in basal hormone levels, but a heightened sympathetic adrenomedullary response to stress. While these results indicate that the integrity of the habenular efferent pathway is important in modulating circulating levels of hormones associated with the stress response, two separate mechanisms appear to control its interactions with sympathetic

Thermal Equilibrium Dynamic Control Based on DPWM Dual-Mode Modulation of High Power NPC Three-Level Inverter

OpenAIRE

Xu, Shi-Zhou; He, Feng-You

2016-01-01

In some special applications of NPC three-level inverters, such as mine hoist, there exist special conditions of overloading during the whole hoisting process and large overload in starting stage, during which the power-loss calculation of power devices and thermal control are important factors affecting the thermal stability of inverters. The principles of SVPWM and DPWM were described in this paper firstly, based on which the dynamic power losses of the two modulations of hoist in single pe...

A Comprehensive Investigation on the Short Circuit Performance of MW-level IGBT Power Modules

DEFF Research Database (Denmark)

Wu, Rui; Reigosa, Paula Diaz; Iannuzzo, Francesco

2015-01-01

This paper investigates the short circuit performance of commercial 1.7 kV / 1 kA IGBT power modules by means of a 6 kA Non-Destructive-Tester. A mismatched current distribution among the parallel chips has been observed, which can reduce the short circuit capability of the IGBT power module unde...... short circuit conditions. Further Spice simulations reveal that the stray parameters inside the module play an important role in contributing to such a phenomenon....

Resveratrol confers protection against rotenone-induced neurotoxicity by modulating myeloperoxidase levels in glial cells.

Directory of Open Access Journals (Sweden)

Chi Young Chang

Full Text Available Myeloperoxidase (MPO functions as a key molecular component of the host defense system against diverse pathogens. We have previously reported that increased MPO levels and activity is a distinguishing feature of rotenone-exposed glial cells, and that either overactivation or deficiency of MPO leads to pathological conditions in the brain. Here, we provide that modulation of MPO levels in glia by resveratrol confers protective effects on rotenone-induced neurotoxicity. We show that resveratrol significantly reduced MPO levels but did not trigger abnormal nitric oxide (NO production in microglia and astrocytes. Resveratrol-induced down-regulation of MPO, in the absence of an associated overproduction of NO, markedly attenuated rotenone-triggered inflammatory responses including phagocytic activity and reactive oxygen species production in primary microglia and astrocytes. In addition, impaired responses of primary mixed glia from Mpo (-/- mice to rotenone were relieved by treatment with resveratrol. We further show that rotenone-induced neuronal injury, particularly dopaminergic cell death, was attenuated by resveratrol in neuron-glia co-cultures, but not in neurons cultured alone. Similar regulatory effects of resveratrol on MPO levels were observed in microglia treated with MPP(+, another Parkinson's disease-linked neurotoxin, supporting the beneficial effects of resveratrol on the brain. Collectively, our findings provide that resveratrol influences glial responses to rotenone by regulating both MPO and NO, and thus protects against rotenone-induced neuronal injury.

Bunch identification module

International Nuclear Information System (INIS)

Fox, J.D.

1981-01-01

This module provides bunch identification and timing signals for the PEP Interaction areas. Timing information is referenced to the PEP master oscillator, and adjusted in phase as a function of region. Identification signals are generated in a manner that allows observers in all interaction regions to agree on an unambiguous bunch identity. The module provides bunch identification signals via NIM level logic, upon CAMAC command, and through LED indicators. A front panel ''region select'' switch allows the same module to be used in all regions. The module has two modes of operation: a bunch identification mode and a calibration mode. In the identification mode, signals indicate which of the three bunches of electrons and positrons are interacting, and timing information about beam crossing is provided. The calibration mode is provided to assist experimenters making time of flight measurements. In the calibration mode, three distinct gating signals are referenced to a selected bunch, allowing three timing systems to be calibrated against a common standard. Physically, the bunch identifier is constructed as a single width CAMAC module. 2 figs., 1 tab

A genome-scale RNA-interference screen identifies RRAS signaling as a pathologic feature of Huntington's disease.

Directory of Open Access Journals (Sweden)

John P Miller

Full Text Available A genome-scale RNAi screen was performed in a mammalian cell-based assay to identify modifiers of mutant huntingtin toxicity. Ontology analysis of suppressor data identified processes previously implicated in Huntington's disease, including proteolysis, glutamate excitotoxicity, and mitochondrial dysfunction. In addition to established mechanisms, the screen identified multiple components of the RRAS signaling pathway as loss-of-function suppressors of mutant huntingtin toxicity in human and mouse cell models. Loss-of-function in orthologous RRAS pathway members also suppressed motor dysfunction in a Drosophila model of Huntington's disease. Abnormal activation of RRAS and a down-stream effector, RAF1, was observed in cellular models and a mouse model of Huntington's disease. We also observe co-localization of RRAS and mutant huntingtin in cells and in mouse striatum, suggesting that activation of R-Ras may occur through protein interaction. These data indicate that mutant huntingtin exerts a pathogenic effect on this pathway that can be corrected at multiple intervention points including RRAS, FNTA/B, PIN1, and PLK1. Consistent with these results, chemical inhibition of farnesyltransferase can also suppress mutant huntingtin toxicity. These data suggest that pharmacological inhibition of RRAS signaling may confer therapeutic benefit in Huntington's disease.

Medical Terminology: Prefixes. Health Occupations Education Module.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on medical terminology (prefixes) is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module consists of an introduction to prefixes, a list of resources needed, and three learning experiences. Each learning experience contains an…

Transgenic animal models for study of the pathogenesis of Huntington’s disease and therapy

Directory of Open Access Journals (Sweden)

Chang RB

2015-04-01

Full Text Available Renbao Chang,1 Xudong Liu,1 Shihua Li,2 Xiao-Jiang Li1,2 1State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, People’s Republic of China; 2Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA Abstract: Huntington’s disease (HD is caused by a genetic mutation that results in polyglutamine expansion in the N-terminal regions of huntingtin. As a result, this polyQ expansion leads to the misfolding and aggregation of mutant huntingtin as well as age-dependent neurodegeneration. The genetic mutation in HD allows for generating a variety of animal models that express different forms of mutant huntingtin and show differential pathology. Studies of these animal models have provided an important insight into the pathogenesis of HD. Mouse models of HD include transgenic mice, which express N-terminal or full-length mutant huntingtin ubiquitously or selectively in different cell types, and knock-in mice that express full-length mutant Htt at the endogenous level. Large animals, such as pig, sheep, and monkeys, have also been used to generate animal HD models. This review focuses on the different features of commonly used transgenic HD mouse models as well as transgenic large animal models of HD, and also discusses how to use them to identify potential therapeutics. Since HD shares many pathological features with other neurodegenerative diseases, identification of therapies for HD would also help to develop effective treatment for different neurodegenerative diseases that are also caused by protein misfolding and occur in an age-dependent manner. Keywords: transgenic animal models, Huntington’s disease, pathogenesis, therapy

Medical Terminology: Root Words. Health Occupations Education Module.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on medical terminology (root words) is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module consists of an introduction to root words, a list of resources needed, procedures for using the module, a list of terminology used in the…

Cell-to-module optical loss/gain analysis for various photovoltaic module materials through systematic characterization

Science.gov (United States)

Hsian Saw, Min; Khoo, Yong Sheng; Singh, Jai Prakash; Wang, Yan

2017-08-01

Reducing levelized cost of electricity (LCOE) is important for solar photovoltaics to compete against other energy sources. Thus, the focus should not only be on improving the solar cell efficiency, but also on continuously reducing the losses (or achieving gain) in the cell-to-module process. This can be achieved by choosing the appropriate module material and design. This paper presents a detailed and systematic characterization of various photovoltaic (PV) module materials (encapsulants, tabbing ribbons, and backsheets) and an evaluation of their impact on the output power of silicon wafer-based PV modules. Various characterization tools/techniques, such as UV-vis (reflectance) measurement, external quantum efficiency (EQE) measurement and EQE line-scan are used. Based on the characterization results, we use module materials with the best-evaluated optical performance to build “optimized modules”. Compared to the standard mini-module, an optical gain of more than 5% is achievable for the “optimized module” with selected module materials.

A Temperature-Dependent Thermal Model of IGBT Modules Suitable for Circuit-Level Simulations

DEFF Research Database (Denmark)

Wu, Rui; Wang, Huai; Ma, Ke

2014-01-01

Thermal impedance of IGBT modules may vary with operating conditions due to that the thermal conductivity and heat capacity of materials are temperature dependent. This paper proposes a Cauer thermal model for a 1700 V/1000 A IGBT module with temperature-dependent thermal resistances and thermal ...... relevant reliability aspect performance. A test bench is built up with an ultra-fast infrared (IR) camera to validate the proposed thermal impedance model....

Huntington's disease: a perplexing neurological disease ...

African Journals Online (AJOL)

Huntington's disease is an inherited intricate brain illness. It is a neurodegenerative, insidious disorder; the onset of the disease is very late to diagnose. It is caused by an expanded CAG repeat in the Huntingtin gene, which encodes an abnormally long polyglutamine repeat in the Huntingtin protein. Huntington's disease ...

Positive and negative early life experiences differentially modulate long term survival and amyloid protein levels in a mouse model of Alzheimer's disease.

Science.gov (United States)

Lesuis, Sylvie L; Maurin, Herve; Borghgraef, Peter; Lucassen, Paul J; Van Leuven, Fred; Krugers, Harm J

2016-06-28

Stress has been implicated as a risk factor for the severity and progression of sporadic Alzheimer's disease (AD). Early life experiences determine stress responsivity in later life, and modulate age-dependent cognitive decline. Therefore, we examined whether early life experiences influence AD outcome in a bigenic mouse model which progressively develops combined tau and amyloid pathology (biAT mice).Mice were subjected to either early life stress (ELS) or to 'positive' early handling (EH) postnatally (from day 2 to 9). In biAT mice, ELS significantly compromised long term survival, in contrast to EH which increased life expectancy. In 4 month old mice, ELS-reared biAT mice displayed increased hippocampal Aβ levels, while these levels were reduced in EH-reared biAT mice. No effects of ELS or EH were observed on the brain levels of APP, protein tau, or PSD-95. Dendritic morphology was moderately affected after ELS and EH in the amygdala and medial prefrontal cortex, while object recognition memory and open field performance were not affected. We conclude that despite the strong transgenic background, early life experiences significantly modulate the life expectancy of biAT mice. Parallel changes in hippocampal Aβ levels were evident, without affecting cognition of young adult biAT mice.

Modulation of gene expression made easy

DEFF Research Database (Denmark)

Solem, Christian; Jensen, Peter Ruhdal

2002-01-01

A new approach for modulating gene expression, based on randomization of promoter (spacer) sequences, was developed. The method was applied to chromosomal genes in Lactococcus lactis and shown to generate libraries of clones with broad ranges of expression levels of target genes. In one example...... that the method can be applied to modulating the expression of native genes on the chromosome. We constructed a series of strains in which the expression of the las operon, containing the genes pfk, pyk, and ldh, was modulated by integrating a truncated copy of the pfk gene. Importantly, the modulation affected...

Automatic modulation classification principles, algorithms and applications

CERN Document Server

Zhu, Zhechen

2014-01-01

Automatic Modulation Classification (AMC) has been a key technology in many military, security, and civilian telecommunication applications for decades. In military and security applications, modulation often serves as another level of encryption; in modern civilian applications, multiple modulation types can be employed by a signal transmitter to control the data rate and link reliability. This book offers comprehensive documentation of AMC models, algorithms and implementations for successful modulation recognition. It provides an invaluable theoretical and numerical comparison of AMC algo

Ageing monitoring in IGBT module under sinusoidal loading

DEFF Research Database (Denmark)

Ghimire, Pramod; Pedersen, Kristian Bonderup; Rannestad, Bjørn

2015-01-01

This paper presents monitoring of ageing in high power insulated gate bipolar transistor (IGBT) modules subjected to sinusoidal loading at nominal power level. On-state voltage for IGBT, diode, and rise in interconnection resistance are used as ageing parameters. These are measured in three...... different ways: calibration of power modules after 24 h of operation, offline characterization every 5 min of operation, and continuous measurement during normal converter operation. Four power modules are tested, which are cycled to different degradation levels by number of cycles, where one is tested...

Level of processing modulates the neural correlates of emotional memory formation.

Science.gov (United States)

Ritchey, Maureen; LaBar, Kevin S; Cabeza, Roberto

2011-04-01

Emotion is known to influence multiple aspects of memory formation, including the initial encoding of the memory trace and its consolidation over time. However, the neural mechanisms whereby emotion impacts memory encoding remain largely unexplored. The present study used a levels-of-processing manipulation to characterize the impact of emotion on encoding with and without the influence of elaborative processes. Participants viewed emotionally negative, neutral, and positive scenes under two conditions: a shallow condition focused on the perceptual features of the scenes and a deep condition that queried their semantic meaning. Recognition memory was tested 2 days later. Results showed that emotional memory enhancements were greatest in the shallow condition. fMRI analyses revealed that the right amygdala predicted subsequent emotional memory in the shallow more than deep condition, whereas the right ventrolateral PFC demonstrated the reverse pattern. Furthermore, the association of these regions with the hippocampus was modulated by valence: the amygdala-hippocampal link was strongest for negative stimuli, whereas the prefrontal-hippocampal link was strongest for positive stimuli. Taken together, these results suggest two distinct activation patterns underlying emotional memory formation: an amygdala component that promotes memory during shallow encoding, especially for negative information, and a prefrontal component that provides extra benefits during deep encoding, especially for positive information.

Level of processing modulates the neural correlates of emotional memory formation

Science.gov (United States)

Ritchey, Maureen; LaBar, Kevin S.; Cabeza, Roberto

2010-01-01

Emotion is known to influence multiple aspects of memory formation, including the initial encoding of the memory trace and its consolidation over time. However, the neural mechanisms whereby emotion impacts memory encoding remain largely unexplored. The present study employed a levels-of-processing manipulation to characterize the impact of emotion on encoding with and without the influence of elaborative processes. Participants viewed emotionally negative, neutral, and positive scenes under two conditions: a shallow condition focused on the perceptual features of the scenes and a deep condition that queried their semantic meaning. Recognition memory was tested 2 days later. Results showed that emotional memory enhancements were greatest in the shallow condition. FMRI analyses revealed that the right amygdala predicted subsequent emotional memory in the shallow more than deep condition, whereas the right ventrolateral prefrontal cortex demonstrated the reverse pattern. Furthermore, the association of these regions with the hippocampus was modulated by valence: the amygdala-hippocampal link was strongest for negative stimuli, whereas the prefrontal-hippocampal link was strongest for positive stimuli. Taken together, these results suggest two distinct activation patterns underlying emotional memory formation: an amygdala component that promotes memory during shallow encoding, especially for negative information, and a prefrontal component that provides extra benefits during deep encoding, especially for positive information. PMID:20350176

Self-synchronization of the modulation of energy-levels population with electrons in GaAs induced by picosecond pulses of probe radiation and intrinsic stimulated emission

Energy Technology Data Exchange (ETDEWEB)

Ageeva, N. N.; Bronevoi, I. L., E-mail: bil@cplire.ru; Zabegaev, D. N.; Krivonosov, A. N. [Russian Academy of Sciences, Kotel’nikov Institute of Radioengineering and Electronics (Russian Federation)

2016-10-15

Picosecond optical pumping leads to the initiation of intrinsic picosecond stimulated emission in GaAs. As was established previously, due to the interaction of pulses of probe radiation with those of intrinsic emission, the dependence of the absorption α of the probe pulse on its delay τ with respect to the pump pulse is modulated with oscillations. It is found that the oscillatory dependences α(τ) have a similar shape only in the case of certain combinations of energies of the interacting pulses. As a result, it is assumed that the above interaction is, in fact, a synchronization of modulations (formed by pulses) of charge-carrier populations at energy levels; this synchronization occurs in the direction of the reconstruction of detailed equilibrium. The real-time picosecond self-modulation of the absorption α is measured for the first time. The characteristics of this self-modulation as well as absorption α and intrinsic emission self-modulation characteristics measured previously by correlation methods are now accounted for by the concept of synchronization.

Temporal modulation transfer functions in cochlear implantees using a method that limits overall loudness cues

Science.gov (United States)

Fraser, Matthew; McKay, Colette M.

2012-01-01

Temporal modulation transfer functions (TMTFs) were measured for six users of cochlear implants, using different carrier rates and levels. Unlike most previous studies investigating modulation detection, the experimental design limited potential effects of overall loudness cues. Psychometric functions (percent correct discrimination of modulated from unmodulated stimuli versus modulation depth) were obtained. For each modulation depth, each modulated stimulus was loudness balanced to the unmodulated reference stimulus, and level jitter was applied in the discrimination task. The loudness-balance data showed that the modulated stimuli were louder than the unmodulated reference stimuli with the same average current, thus confirming the need to limit loudness cues when measuring modulation detection. TMTFs measured in this way had a low-pass characteristic, with a cut-off frequency (at comfortably loud levels) similar to that for normal-hearing listeners. A reduction in level caused degradation in modulation detection efficiency and a lower-cut-off frequency (i.e. poorer temporal resolution). An increase in carrier rate also led to a degradation in modulation detection efficiency, but only at lower levels or higher modulation frequencies. When detection thresholds were expressed as a proportion of dynamic range, there was no effect of carrier rate for the lowest modulation frequency (50 Hz) at either level. PMID:22146425

Space Experiment Module (SEM)

Science.gov (United States)

Brodell, Charles L.

1999-01-01

The Space Experiment Module (SEM) Program is an education initiative sponsored by the National Aeronautics and Space Administration (NASA) Shuttle Small Payloads Project. The program provides nationwide educational access to space for Kindergarten through University level students. The SEM program focuses on the science of zero-gravity and microgravity. Within the program, NASA provides small containers or "modules" for students to fly experiments on the Space Shuttle. The experiments are created, designed, built, and implemented by students with teacher and/or mentor guidance. Student experiment modules are flown in a "carrier" which resides in the cargo bay of the Space Shuttle. The carrier supplies power to, and the means to control and collect data from each experiment.

Module theory, extending modules and generalizations

CERN Document Server

Tercan, Adnan

2016-01-01

The main focus of this monograph is to offer a comprehensive presentation of known and new results on various generalizations of CS-modules and CS-rings. Extending (or CS) modules are generalizations of injective (and also semisimple or uniform) modules. While the theory of CS-modules is well documented in monographs and textbooks, results on generalized forms of the CS property as well as dual notions are far less present in the literature. With their work the authors provide a solid background to module theory, accessible to anyone familiar with basic abstract algebra. The focus of the book is on direct sums of CS-modules and classes of modules related to CS-modules, such as relative (injective) ejective modules, (quasi) continuous modules, and lifting modules. In particular, matrix CS-rings are studied and clear proofs of fundamental decomposition results on CS-modules over commutative domains are given, thus complementing existing monographs in this area. Open problems round out the work and establish the...

Inactivation of the Huntington's disease gene (Hdh impairs anterior streak formation and early patterning of the mouse embryo

Directory of Open Access Journals (Sweden)

Conlon Ronald A

2005-08-01

Full Text Available Abstract Background Huntingtin, the HD gene encoded protein mutated by polyglutamine expansion in Huntington's disease, is required in extraembryonic tissues for proper gastrulation, implicating its activities in nutrition or patterning of the developing embryo. To test these possibilities, we have used whole mount in situ hybridization to examine embryonic patterning and morphogenesis in homozygous Hdhex4/5 huntingtin deficient embryos. Results In the absence of huntingtin, expression of nutritive genes appears normal but E7.0–7.5 embryos exhibit a unique combination of patterning defects. Notable are a shortened primitive streak, absence of a proper node and diminished production of anterior streak derivatives. Reduced Wnt3a, Tbx6 and Dll1 expression signify decreased paraxial mesoderm and reduced Otx2 expression and lack of headfolds denote a failure of head development. In addition, genes initially broadly expressed are not properly restricted to the posterior, as evidenced by the ectopic expression of Nodal, Fgf8 and Gsc in the epiblast and T (Brachyury and Evx1 in proximal mesoderm derivatives. Despite impaired posterior restriction and anterior streak deficits, overall anterior/posterior polarity is established. A single primitive streak forms and marker expression shows that the anterior epiblast and anterior visceral endoderm (AVE are specified. Conclusion Huntingtin is essential in the early patterning of the embryo for formation of the anterior region of the primitive streak, and for down-regulation of a subset of dynamic growth and transcription factor genes. These findings provide fundamental starting points for identifying the novel cellular and molecular activities of huntingtin in the extraembryonic tissues that govern normal anterior streak development. This knowledge may prove to be important for understanding the mechanism by which the dominant polyglutamine expansion in huntingtin determines the loss of neurons in

Inactivation of the Huntington's disease gene (Hdh) impairs anterior streak formation and early patterning of the mouse embryo.

Science.gov (United States)

Woda, Juliana M; Calzonetti, Teresa; Hilditch-Maguire, Paige; Duyao, Mabel P; Conlon, Ronald A; MacDonald, Marcy E

2005-08-18

Huntingtin, the HD gene encoded protein mutated by polyglutamine expansion in Huntington's disease, is required in extraembryonic tissues for proper gastrulation, implicating its activities in nutrition or patterning of the developing embryo. To test these possibilities, we have used whole mount in situ hybridization to examine embryonic patterning and morphogenesis in homozygous Hdh(ex4/5) huntingtin deficient embryos. In the absence of huntingtin, expression of nutritive genes appears normal but E7.0-7.5 embryos exhibit a unique combination of patterning defects. Notable are a shortened primitive streak, absence of a proper node and diminished production of anterior streak derivatives. Reduced Wnt3a, Tbx6 and Dll1 expression signify decreased paraxial mesoderm and reduced Otx2 expression and lack of headfolds denote a failure of head development. In addition, genes initially broadly expressed are not properly restricted to the posterior, as evidenced by the ectopic expression of Nodal, Fgf8 and Gsc in the epiblast and T (Brachyury) and Evx1 in proximal mesoderm derivatives. Despite impaired posterior restriction and anterior streak deficits, overall anterior/posterior polarity is established. A single primitive streak forms and marker expression shows that the anterior epiblast and anterior visceral endoderm (AVE) are specified. Huntingtin is essential in the early patterning of the embryo for formation of the anterior region of the primitive streak, and for down-regulation of a subset of dynamic growth and transcription factor genes. These findings provide fundamental starting points for identifying the novel cellular and molecular activities of huntingtin in the extraembryonic tissues that govern normal anterior streak development. This knowledge may prove to be important for understanding the mechanism by which the dominant polyglutamine expansion in huntingtin determines the loss of neurons in Huntington's disease.

Diffusion tensor imaging of brain white matter in Huntington gene mutation individuals

Directory of Open Access Journals (Sweden)

Roberta Arb Saba

Full Text Available ABSTRACT Objective To evaluate the role of the involvement of white matter tracts in huntingtin gene mutation patients as a potential biomarker of the progression of the disease. Methods We evaluated 34 participants (11 symptomatic huntingtin gene mutation, 12 presymptomatic huntingtin gene mutation, and 11 controls. We performed brain magnetic resonance imaging to assess white matter integrity using diffusion tensor imaging, with measurement of fractional anisotropy. Results We observed a significant decrease of fractional anisotropy in the cortical spinal tracts, corona radiate, corpus callosum, external capsule, thalamic radiations, superior and inferior longitudinal fasciculus, and inferior frontal-occipital fasciculus in the Huntington disease group compared to the control and presymptomatic groups. Reduction of fractional anisotropy is indicative of a degenerative process and axonal loss. There was no statistically significant difference between the presymptomatic and control groups. Conclusion White matter integrity is affected in huntingtin gene mutation symptomatic individuals, but other studies with larger samples are required to assess its usefulness in the progression of the neurodegenerative process.

Fermilab Linac Upgrade: Module conditioning results

International Nuclear Information System (INIS)

Kroc, T.; Moretti, A.; Popovic, M.

1992-12-01

The 805 MHz Side-coupled cavity modules for the Fermilab 400 MeV linac upgrade have been conditioned to accept full power. The sparking rate in the cavities and in the side-cells has been reduced to acceptable levels. It required approximately 40 x 10 6 pulses for each module to achieve an adequately low sparking rate. This contribution outlines the commissioning procedure, presents the sparking rate improvements and the radiation level improvements through the commissioning process and disc the near-online commissioning plans for this accelerator

Pulse width and height modulation for multi-level resistance in bi-layer TaOx based RRAM

Science.gov (United States)

Alamgir, Zahiruddin; Beckmann, Karsten; Holt, Joshua; Cady, Nathaniel C.

2017-08-01

Mutli-level switching in resistive memory devices enables a wide range of computational paradigms, including neuromorphic and cognitive computing. To this end, we have developed a bi-layer tantalum oxide based resistive random access memory device using Hf as the oxygen exchange layer. Multiple, discrete resistance levels were achieved by modulating the RESET pulse width and height, ranging from 2 kΩ to several MΩ. For a fixed pulse height, OFF state resistance was found to increase gradually with the increase in the pulse width, whereas for a fixed pulse width, the increase in the pulse height resulted in drastic changes in resistance. Resistive switching in these devices transitioned from Schottky emission in the OFF state to tunneling based conduction in the ON state, based on I-V curve fitting and temperature dependent current measurements. These devices also demonstrated endurance of more than 108 cycles with a satisfactory Roff/Ron ratio and retention greater than 104 s.

Challenges of Huntington's disease and quest for therapeutic biomarkers

Czech Academy of Sciences Publication Activity Database

Kotrčová, Eva; Jarkovská, Karla; Valeková, Ivona; Žižková, Martina; Motlík, Jan; Gadher, S. J.; Kovářová, Hana

2015-01-01

Roč. 9, 1-2 (2015), s. 147-158 ISSN 1862-8346 R&D Projects: GA MŠk ED2.1.00/03.0124; GA TA ČR(CZ) TA01011466 Institutional support: RVO:67985904 Keywords : HD biomarkers * Huntington´s disease * Huntingtin neurotoxicity * Huntingtin pathogenesis Subject RIV: FH - Neurology Impact factor: 2.959, year: 2015

Modulated Raman Spectroscopy for Enhanced Cancer Diagnosis at the Cellular Level

Science.gov (United States)

De Luca, Anna Chiara; Dholakia, Kishan; Mazilu, Michael

2015-01-01

Raman spectroscopy is emerging as a promising and novel biophotonics tool for non-invasive, real-time diagnosis of tissue and cell abnormalities. However, the presence of a strong fluorescence background is a key issue that can detract from the use of Raman spectroscopy in routine clinical care. The review summarizes the state-of-the-art methods to remove the fluorescence background and explores recent achievements to address this issue obtained with modulated Raman spectroscopy. This innovative approach can be used to extract the Raman spectral component from the fluorescence background and improve the quality of the Raman signal. We describe the potential of modulated Raman spectroscopy as a rapid, inexpensive and accurate clinical tool to detect the presence of bladder cancer cells. Finally, in a broader context, we show how this approach can greatly enhance the sensitivity of integrated Raman spectroscopy and microfluidic systems, opening new prospects for portable higher throughput Raman cell sorting. PMID:26110401

Spin-wave propagation spectrum in magnetization-modulated cylindrical nanowires

Energy Technology Data Exchange (ETDEWEB)

Li, Zhi-xiong; Wang, Meng-ning; Nie, Yao-zhuang; Wang, Dao-wei; Xia, Qing-lin [School of Physics and Electronics, Central South University, Changsha 410083 (China); Tang, Wei [School of Physics and Electronics, Central South University, Changsha 410083 (China); Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Zeng, Zhong-ming [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Guo, Guang-hua, E-mail: guogh@mail.csu.edu.cn [School of Physics and Electronics, Central South University, Changsha 410083 (China)

2016-09-15

Spin-wave propagation in periodic magnetization-modulated cylindrical nanowires is studied by micromagnetic simulation. Spin wave scattering at the interface of two magnetization segments causes a spin-wave band structure, which can be effectively tuned by changing either the magnetization modulation level or the period of the cylindrical nanowire magnonic crystal. The bandgap width is oscillating with either the period or magnetization modulation due to the oscillating variation of the spin wave transmission coefficient through the interface of the two magnetization segments. Analytical calculation based on band theory is used to account for the micromagnetic simulation results. - Highlights: • A magnetization-modulated cylindrical nanowire magnonic crystal is proposed. • Propagating characteristics of spin waves in such magnonic crystal are studied. • Spin-wave spectra can be manipulated by changing modulation level and period.

Fermilab linac upgrade. Module conditioning results

International Nuclear Information System (INIS)

Kroc, T.; Moretti, A.; Popovic, M.

1992-01-01

The 805 MHz side-coupled cavity modules for the Fermilab 400 MeV linac upgrade have been conditioned to accept full power. The sparking rate in the cavities and in the side cells has been reduced to acceptable levels. It required approximately 40 x 10 6 pulses for each module to achieve an adequately low sparking rate. This contribution outlines the commissioning procedure, presents the sparking rate improvements and the radiation level improvements through the commissioning process and discusses the near-on-line commissioning plans for this accelerator. (Author) ref., 4 figs

Modulation of neurological related allergic reaction in mice exposed to low-level toluene

International Nuclear Information System (INIS)

Tin-Tin-Win-Shwe; Yamamoto, Shoji; Nakajima, Daisuke; Furuyama, Akiko; Fukushima, Atsushi; Ahmed, Sohel; Goto, Sumio; Fujimaki, Hidekazu

2007-01-01

The contributing role of indoor air pollution to the development of allergic disease has become increasingly evident in public health problems. It has been reported that extensive communication exists between neurons and immune cells, and neurotrophins are molecules potentially responsible for regulating and controlling this neuroimmune crosstalk. The adverse effects of volatile organic compounds which are main indoor pollutants on induction or augmentation of neuroimmune interaction have not been fully characterized yet. To investigate the effects of low-level toluene inhalation on the airway inflammatory responses, male C3H mice were exposed to filtered air (control), 9 ppm, and 90 ppm toluene for 30 min by nose-only inhalation on Days 0, 1, 2, 7, 14, 21, and 28. Some groups of mice were injected with ovalbumin intraperitoneally before starting exposure schedule and these mice were then challenged with aerosolized ovalbumin as booster dose. For analysis of airway inflammation, bronchoalveolar lavage (BAL) fluid were collected to determine inflammatory cell influx and lung tissue and blood samples were collected to determine cytokine and neurotrophin mRNA and protein expressions and plasma antibody titers using real-time RT-PCR and ELISA methods respectively. Exposure of the ovalbumin-immunized mice to low-level toluene resulted in (1) increased inflammatory cells infiltration in BAL fluid; (2) increased IL-5 mRNA, decreased nerve growth factor receptor tropomyosin-related kinase A and brain-derived neurotrophic factor mRNAs in lung; and (3) increased IgE and IgG 1 antibodies and nerve growth factor content in the plasma. These findings suggest that low-level toluene exposure aggravates the airway inflammatory responses in ovalbumin-immunized mice by modulating neuroimmune crosstalk

Comparing the effects of age on amplitude modulation and frequency modulation detection.

Science.gov (United States)

Wallaert, Nicolas; Moore, Brian C J; Lorenzi, Christian

2016-06-01

Frequency modulation (FM) and amplitude modulation (AM) detection thresholds were measured at 40 dB sensation level for young (22-28 yrs) and older (44-66 yrs) listeners with normal audiograms for a carrier frequency of 500 Hz and modulation rates of 2 and 20 Hz. The number of modulation cycles, N, varied between 2 and 9. For FM detection, uninformative AM at the same rate as the FM was superimposed to disrupt excitation-pattern cues. For both groups, AM and FM detection thresholds were lower for the 2-Hz than for the 20-Hz rate, and AM and FM detection thresholds decreased with increasing N. Thresholds were higher for older than for younger listeners, especially for FM detection at 2 Hz, possibly reflecting the effect of age on the use of temporal-fine-structure cues for 2-Hz FM detection. The effect of increasing N was similar across groups for both AM and FM. However, at 20 Hz, older listeners showed a greater effect of increasing N than younger listeners for both AM and FM. The results suggest that ageing reduces sensitivity to both excitation-pattern and temporal-fine-structure cues for modulation detection, but more so for the latter, while sparing temporal integration of these cues at low modulation rates.

Evolutionary and developmental modules.

Science.gov (United States)

Lacquaniti, Francesco; Ivanenko, Yuri P; d'Avella, Andrea; Zelik, Karl E; Zago, Myrka

2013-01-01

The identification of biological modules at the systems level often follows top-down decomposition of a task goal, or bottom-up decomposition of multidimensional data arrays into basic elements or patterns representing shared features. These approaches traditionally have been applied to mature, fully developed systems. Here we review some results from two other perspectives on modularity, namely the developmental and evolutionary perspective. There is growing evidence that modular units of development were highly preserved and recombined during evolution. We first consider a few examples of modules well identifiable from morphology. Next we consider the more difficult issue of identifying functional developmental modules. We dwell especially on modular control of locomotion to argue that the building blocks used to construct different locomotor behaviors are similar across several animal species, presumably related to ancestral neural networks of command. A recurrent theme from comparative studies is that the developmental addition of new premotor modules underlies the postnatal acquisition and refinement of several different motor behaviors in vertebrates.

Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

Directory of Open Access Journals (Sweden)

Françoise eLecaignard

2015-09-01

Full Text Available Deviant stimuli, violating regularities in a sensory environment, elicit the Mismatch Negativity (MMN, largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities.

Modulation of plasma N-acylethanolamine levels and physiological parameters by dietary fatty acid composition in humans.

Science.gov (United States)

Jones, Peter J H; Lin, Lin; Gillingham, Leah G; Yang, Haifeng; Omar, Jaclyn M

2014-12-01

N-Acylethanolamines (NAEs) are endogenous lipid-signaling molecules involved in satiety and energetics; however, how diet impacts circulating NAE concentrations and their downstream metabolic actions in humans remains unknown. Objectives were to examine effects of diets enriched with high-oleic canola oil (HOCO) or HOCO blended with flaxseed oil (FXCO), compared with a Western diet (WD), on plasma NAE levels and the association with energy expenditure and substrate oxidation. Using a randomized controlled crossover design, 36 hypercholesterolemic participants consumed three isoenergetic diets for 28 days, each containing 36% energy from fat, of which 70% was HOCO, FXCO, or WD. Ultra-performance liquid chromatography-MS/MS was used to measure plasma NAE levels and indirect calorimetry to assess energy expenditure and substrate oxidation. After 28 days, compared with WD, plasma oleoylethanolamide (OEA) and alpha-linolenoyl ethanolamide (ALEA) levels were significantly increased in response to HOCO and FXCO (P = 0.002, P < 0.001), respectively. Correlation analysis demonstrated an inverse association between plasma OEA levels and percent body fat (r = -0.21, P = 0.04), and a positive association was observed between the plasma arachidonoyl ethanolamide (AEA)/OEA ratio and android:gynoid fat (r = 0.23, P = 0.02), respectively. Results suggest that plasma NAE levels are upregulated via their dietary lipid substrates and may modulate regional and total fat mass through lipid-signaling mechanisms. Copyright © 2014 by the American Society for Biochemistry and Molecular Biology, Inc.

Parvovirus B19 infection modulates the levels of cytokines in the plasma of rheumatoid arthritis patients.

Science.gov (United States)

Naciute, Milda; Mieliauskaite, Diana; Rugiene, Rita; Maciunaite, Gabriele; Mauricas, Mykolas; Murovska, Modra; Girkontaite, Irute

2017-08-01

Parvovirus B19 (B19V) infection is associated with various autoimmune diseases. We investigated the levels of pro-inflammatory (IFNᵧ, TNFα, IL-2, IL-12) and anti-inflammatory (IL-4, IL-10) cytokines in the plasma of B19V DNA positive (B19 + ) and negative (B19 - ) rheumatoid arthritis (RA) patients in comparison with the control group (healthy persons). Blood samples were collected from 118 patients with RA and 49 healthy voluntaries. B19V sequence was determined in whole blood and cell-free plasma DNA by nested PCR. The levels of cytokines in the plasma and cell culture medium from Concanavalin A (ConA) or B19V VP1 protein stimulated PBMC were determined by ELISA. The levels of IL-4, IL-10, IL-12, IL-2 and TNFα were higher in plasma of RA patients in comparison with control persons. B19 + controls and RA patients had lower levels of IFNᵧ in comparison with B19 - controls and RA patients. Within RA patients the plasma levels of IFNᵧ were lower in patients with low RA disease activity or remission. Plasma level of IL-4 was increased and IL-10 level was decreased in B19 + RA patients in comparison with B19 - RA patients and did not differ between B19 + and B19 - controls. B19V infection did not affect plasma levels of IL-12, IL-2, and TNFα. ConA and B19 VP1 protein stimulated PBMC from RA patients produced less IFNᵧ than stimulated PBMC from the healthy controls. B19V infection could differently modulate the amount of cytokines in the plasma of healthy persons and RA patients. Decreased production of IFNᵧ and raised level of plasma IL-4 in RA patients could lower antiviral clearance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Irreducible Specht modules are signed Young modules

OpenAIRE

Hemmer, David J.

2005-01-01

Recently Donkin defined signed Young modules as a simultaneous generalization of Young and twisted Young modules for the symmetric group. We show that in odd characteristic, if a Specht module $S^\\lambda$ is irreducible, then $S^\\lambda$ is a signed Young module. Thus the set of irreducible Specht modules coincides with the set of irreducible signed Young modules. This provides evidence for our conjecture that the signed Young modules are precisely the class of indecomposable self-dual module...

Self-balanced modulation and magnetic rebalancing method for parallel multilevel inverters

Science.gov (United States)

Li, Hui; Shi, Yanjun

2017-11-28

A self-balanced modulation method and a closed-loop magnetic flux rebalancing control method for parallel multilevel inverters. The combination of the two methods provides for balancing of the magnetic flux of the inter-cell transformers (ICTs) of the parallel multilevel inverters without deteriorating the quality of the output voltage. In various embodiments a parallel multi-level inverter modulator is provide including a multi-channel comparator to generate a multiplexed digitized ideal waveform for a parallel multi-level inverter and a finite state machine (FSM) module coupled to the parallel multi-channel comparator, the FSM module to receive the multiplexed digitized ideal waveform and to generate a pulse width modulated gate-drive signal for each switching device of the parallel multi-level inverter. The system and method provides for optimization of the output voltage spectrum without influence the magnetic balancing.

APPLICATION OF ROUGH SET THEORY TO MAINTENANCE LEVEL DECISION-MAKING FOR AERO-ENGINE MODULES BASED ON INCREMENTAL KNOWLEDGE LEARNING

Institute of Scientific and Technical Information of China (English)

陆晓华; 左洪福; 蔡景

2013-01-01

The maintenance of an aero-engine usually includes three levels ,and the maintenance cost and period greatly differ depending on the different maintenance levels .To plan a reasonable maintenance budget program , airlines would like to predict the maintenance level of aero-engine before repairing in terms of performance parame-ters ,which can provide more economic benefits .The maintenance level decision rules are mined using the histori-cal maintenance data of a civil aero-engine based on the rough set theory ,and a variety of possible models of upda-ting rules produced by newly increased maintenance cases added to the historical maintenance case database are in-vestigated by the means of incremental machine learning .The continuously updated rules can provide reasonable guidance suggestions for engineers and decision support for planning a maintenance budget program before repai-ring .The results of an example show that the decision rules become more typical and robust ,and they are more accurate to predict the maintenance level of an aero-engine module as the maintenance data increase ,which illus-trates the feasibility of the represented method .

Moderate variations in CDC25B protein levels modulate the response to DNA damaging agents

International Nuclear Information System (INIS)

Aressy, B.; Bugler, B.; Valette, A.; Ducommun, B.; Biard, D.

2008-01-01

CDC25B, one of the three members of the CDC25 dual-specificity phosphatase family, plays a critical role in the control of the cell cycle and in the checkpoint response to DNA damage. CDC25B is responsible for the initial dephosphorylation and activation of the cyclin-dependent kinases, thus initiating the train of events leading to entry into mitosis. The critical role played by CDC25B is illustrated by the fact that it is specifically required for checkpoint recovery and that unscheduled accumulation of CDC25B is responsible for illegitimate entry into mitosis. Here, we report that in p53 colon carcinoma cells, a moderate increase in the CDC25B level is sufficient to impair the DNA damage checkpoint, to increase spontaneous mutagenesis, and to sensitize cells to ionising radiation and genotoxic agents. Using a tumour cell spheroid assay as an alternative to animal studies, we demonstrate that the level of CDC25B expression modulates growth inhibition and apoptotic death. Since CDC25B overexpression has been observed in a significant number of human cancers, including colon carcinoma, and is often associated with high grade tumours and poor prognosis, our work suggests that the expression level of CDC25B might be a potential key parameter of the cellular response to cancer therapy. (authors)

The Pseudomonas aeruginosa Chp Chemosensory System Regulates Intracellular cAMP Levels by Modulating Adenylate Cyclase Activity

Science.gov (United States)

Fulcher, Nanette B.; Holliday, Phillip M.; Klem, Erich; Cann, Martin J.; Wolfgang, Matthew C.

2010-01-01

Summary Multiple virulence systems in the opportunistic pathogen Pseudomonas aeruginosa are regulated by the second messenger signaling molecule adenosine 3’, 5’-cyclic monophosphate (cAMP). Production of cAMP by the putative adenylate cyclase enzyme CyaB represents a critical control point for virulence gene regulation. To identify regulators of CyaB, we screened a transposon insertion library for mutants with reduced intracellular cAMP. The majority of insertions resulting in reduced cAMP mapped to the Chp gene cluster encoding a putative chemotaxis-like chemosensory system. Further genetic analysis of the Chp system revealed that it has both positive and negative effects on intracellular cAMP and that it regulates cAMP levels by modulating CyaB activity. The Chp system was previously implicated in the production and function of type IV pili (TFP). Given that cAMP and the cAMP-dependent transcriptional regulator Vfr control TFP biogenesis gene expression, we explored the relationship between cAMP, the Chp system and TFP regulation. We discovered that the Chp system controls TFP production through modulation of cAMP while control of TFP-dependent twitching motility is cAMP-independent. Overall, our data define a novel function for a chemotaxis-like system in controlling cAMP production and establish a regulatory link between the Chp system, TFP and other cAMP-dependent virulence systems. PMID:20345659

Creep Burst Testing of a Woven Inflatable Module

Science.gov (United States)

Selig, Molly M.; Valle, Gerard D.; James, George H.; Oliveras, Ovidio M.; Jones, Thomas C.; Doggett, William R.

2015-01-01

A woven Vectran inflatable module 88 inches in diameter and 10 feet long was tested at the NASA Johnson Space Center until failure from creep. The module was pressurized pneumatically to an internal pressure of 145 psig, and was held at pressure until burst. The external environment remained at standard atmospheric temperature and pressure. The module burst occurred after 49 minutes at the target pressure. The test article pressure and temperature were monitored, and video footage of the burst was captured at 60 FPS. Photogrammetry was used to obtain strain measurements of some of the webbing. Accelerometers on the test article measured the dynamic response. This paper discusses the test article, test setup, predictions, observations, photogrammetry technique and strain results, structural dynamics methods and quick-look results, and a comparison of the module level creep behavior to the strap level creep behavior.

Reducing microwave absorption with fast frequency modulation.

Science.gov (United States)

Qin, Juehang; Hubler, A

2017-05-01

We study the response of a two-level quantum system to a chirp signal, using both numerical and analytical methods. The numerical method is based on numerical solutions of the Schrödinger solution of the two-level system, while the analytical method is based on an approximate solution of the same equations. We find that when two-level systems are perturbed by a chirp signal, the peak population of the initially unpopulated state exhibits a high sensitivity to frequency modulation rate. We also find that the aforementioned sensitivity depends on the strength of the forcing, and weaker forcings result in a higher sensitivity, where the frequency modulation rate required to produce the same reduction in peak population would be lower. We discuss potential applications of this result in the field of microwave power transmission, as it shows applying fast frequency modulation to transmitted microwaves used for power transmission could decrease unintended absorption of microwaves by organic tissue.

Signed Young Modules and Simple Specht Modules

OpenAIRE

Danz, Susanne; Lim, Kay Jin

2015-01-01

By a result of Hemmer, every simple Specht module of a finite symmetric group over a field of odd characteristic is a signed Young module. While Specht modules are parametrized by partitions, indecomposable signed Young modules are parametrized by certain pairs of partitions. The main result of this article establishes the signed Young module labels of simple Specht modules. Along the way we prove a number of results concerning indecomposable signed Young modules that are of independent inter...

GSM module for wireless radiation monitoring system via SMS

Science.gov (United States)

Rahman, Nur Aira Abd; Hisyam Ibrahim, Noor; Lombigit, Lojius; Azman, Azraf; Jaafar, Zainudin; Arymaswati Abdullah, Nor; Hadzir Patai Mohamad, Glam

2018-01-01

A customised Global System for Mobile communication (GSM) module is designed for wireless radiation monitoring through Short Messaging Service (SMS). This module is able to receive serial data from radiation monitoring devices such as survey meter or area monitor and transmit the data as text SMS to a host server. It provides two-way communication for data transmission, status query, and configuration setup. The module hardware consists of GSM module, voltage level shifter, SIM circuit and Atmega328P microcontroller. Microcontroller provides control for sending, receiving and AT command processing to GSM module. The firmware is responsible to handle task related to communication between device and host server. It process all incoming SMS, extract, and store new configuration from Host, transmits alert/notification SMS when the radiation data reach/exceed threshold value, and transmits SMS data at every fixed interval according to configuration. Integration of this module with radiation survey/monitoring device will create mobile and wireless radiation monitoring system with prompt emergency alert at high-level radiation.

Lactobacillus rhamnosus CNCMI-4317 Modulates Fiaf/Angptl4 in Intestinal Epithelial Cells and Circulating Level in Mice.

Science.gov (United States)

Jacouton, Elsa; Mach, Núria; Cadiou, Julie; Lapaque, Nicolas; Clément, Karine; Doré, Joël; van Hylckama Vlieg, Johan E T; Smokvina, Tamara; Blottière, Hervé M

2015-01-01

Identification of new targets for metabolic diseases treatment or prevention is required. In this context, FIAF/ANGPTL4 appears as a crucial regulator of energy homeostasis. Lactobacilli are often considered to display beneficial effect for their hosts, acting on different regulatory pathways. The aim of the present work was to study the effect of several lactobacilli strains on Fiaf gene expression in human intestinal epithelial cells (IECs) and on mice tissues to decipher the underlying mechanisms. Nineteen lactobacilli strains have been tested on HT-29 human intestinal epithelial cells for their ability to regulate Fiaf gene expression by RT-qPCR. In order to determine regulated pathways, we analysed the whole genome transcriptome of IECs. We then validated in vivo bacterial effects using C57BL/6 mono-colonized mice fed with normal chow. We identified one strain (Lactobacillus rhamnosus CNCMI-4317) that modulated Fiaf expression in IECs. This regulation relied potentially on bacterial surface-exposed molecules and seemed to be PPAR-γ independent but PPAR-α dependent. Transcriptome functional analysis revealed that multiple pathways including cellular function and maintenance, lymphoid tissue structure and development, as well as lipid metabolism were regulated by this strain. The regulation of immune system and lipid and carbohydrate metabolism was also confirmed by overrepresentation of Gene Ontology terms analysis. In vivo, circulating FIAF protein was increased by the strain but this phenomenon was not correlated with modulation Fiaf expression in tissues (except a trend in distal small intestine). We showed that Lactobacillus rhamnosus CNCMI-4317 induced Fiaf expression in human IECs, and increased circulating FIAF protein level in mice. Moreover, this effect was accompanied by transcriptome modulation of several pathways including immune response and metabolism in vitro.

Introducing GIS across Levels: Designing for Diversity

Science.gov (United States)

Barros, Joana

2017-01-01

The paper proposes a strategy for designing introductory GIS modules at Birkbeck, University of London. Seven design aspects or elements (content, practical exercises, assessment, pace, mode, level of support, and level of difficulty) for tailoring modules at appropriate levels and for diversity are introduced and their application in Birkbeck's…

Enhanced Cross-Phase Modulation Based on a Double Electromagnetically Induced Transparency in a Four-Level Tripod Atomic System

International Nuclear Information System (INIS)

Li Shujing; Yang Xudong; Cao Xuemin; Zhang Chunhong; Xie Changde; Wang Hai

2008-01-01

We report experimental observations on the simultaneous electromagnetically induced transparency (EIT) effects for probe and trigger fields (double EIT) as well as the enhanced cross-phase modulation (XPM) between the two fields in a four-level tripod EIT system of the D1 line of 87 Rb atoms. The XPM coefficients (larger than 2x10 -5 cm 2 /W) and the accompanying transmissions (higher than 60%) are measured at a slight detuning of the probe field from the exact EIT-resonance condition. The system and enhanced cross-Kerr nonlinearities presented here can be applied to quantum information processes

Effects of periodic modulation on the Landau-Zener transition

International Nuclear Information System (INIS)

Duan Suqing; Fu Libin; Liu Jie; Zhao Xiangeng

2005-01-01

We study the quantum tunnelling of a two-level crossing system which extends the standard Landau-Zener model with applying a periodic modulation on its energy sweep. By directly integrating the time evolution operator we obtain the analytic expressions of tunnelling probability in the cases of high and low modulation frequency limit as well as in weak inter-level coupling limit. Our formula clarify the conditions for resonance occurrence, with the help of it we can readily manipulate the system in a desired way, say, to enhance or suppress the tunnelling probability effectively through adjusting the modulation properly

School based assessment module for invasion games category in ...

African Journals Online (AJOL)

School based assessment module for invasion games category in physical education. ... This study identify the level of basic skills of invasion games category when using School Based Assessment Module. ... AJOL African Journals Online.

Energy rating procedure for PV-modules; Energy rating procedure voor PV-modules

Energy Technology Data Exchange (ETDEWEB)

Van der Borg, N.J.C.M.; Jansen, M.J. [ECN Zon, Petten (Netherlands)

2005-10-15

The performance of PV-modules is usually characterized by the nominal power at standard test conditions. However more relevant for the end-user is the energy production. To arrive at a so-called energy rating procedure the P(G{sub i},T{sub m}) matrix is defined, which makes it possible to calculate the expected annual energy production of a PV-module at any given location with known frequency distribution of horizontal irradiation and ambient temperature. In order to make the de P(G{sub i},T{sub m}) independent of the time and location of the tests the effective irradiation (G{sub i}) is measured with a device with the same characteristics as the module under test. Such a device can be a suitable reference cell or, even better, the module under test itself. The latter, however, is only possible in case the module under test is stable in time. Measurements were performed to test the applicability of the so-called self-reference for a-Si modules. Furthermore the difference between the effective irradiance and the real irradiance (measured with a pyranometer) was quantified for the test location Petten, the Netherlands. The conclusions are: Self-reference is not applicable for a-Si modules because of the time instability, even after 1 full year of degradation; Self-reference signals (the short circuit current of the module under test) can be calibrated outdoor by comparison with a pyranometer at irradiance levels above 800 W/m{sup 2}. The uncertainty of such a calibration is within 3%; The difference between the effective irradiance and the real irradiance on annual basis at Petten is virtually zero for x-Si modules and about 1% for a-Si modules. [Dutch] Het is gebruikelijk om de prestatie van PV-modules te karakteriseren met het nominale vermogen onder standaard testcondities (STC). Echter dit nominaal vermogen geeft geen directe indicatie voor de energieopbrengst. Om tot een karakteristiek voor de energie-opbrengst (energy rating) te komen wordt de prestatie van de

Modelling the Interaction Levels in HCI Using an Intelligent Hybrid System with Interactive Agents: A Case Study of an Interactive Museum Exhibition Module in Mexico

Directory of Open Access Journals (Sweden)

Ricardo Rosales

2018-03-01

Full Text Available Technology has become a necessity in our everyday lives and essential for completing activities we typically take for granted; technologies can assist us by completing set tasks or achieving desired goals with optimal affect and in the most efficient way, thereby improving our interactive experiences. This paper presents research that explores the representation of user interaction levels using an intelligent hybrid system approach with agents. We evaluate interaction levels of Human-Computer Interaction (HCI with the aim of enhancing user experiences. We consider the description of interaction levels using an intelligent hybrid system to provide a decision-making system to an agent that evaluates interaction levels when using interactive modules of a museum exhibition. The agents represent a high-level abstraction of the system, where communication takes place between the user, the exhibition and the environment. In this paper, we provide a means to measure the interaction levels and natural behaviour of users, based on museum user-exhibition interaction. We consider that, by analysing user interaction in a museum, we can help to design better ways to interact with exhibition modules according to the properties and behaviour of the users. An interaction-evaluator agent is proposed to achieve the most suitable representation of the interaction levels with the aim of improving user interactions to offer the most appropriate directions, services, content and information, thereby improving the quality of interaction experienced between the user-agent and exhibition-agent.

Fluorinated Nucleotide Modifications Modulate Allele Selectivity of SNP-Targeting Antisense Oligonucleotides

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Michael E. Østergaard

2017-06-01

Full Text Available Antisense oligonucleotides (ASOs have the potential to discriminate between subtle RNA mismatches such as SNPs. Certain mismatches, however, allow ASOs to bind at physiological conditions and result in RNA cleavage mediated by RNase H. We showed that replacing DNA nucleotides in the gap region of an ASO with other chemical modification can improve allele selectivity. Herein, we systematically substitute every position in the gap region of an ASO targeting huntingtin gene (HTT with fluorinated nucleotides. Potency is determined in cell culture against mutant HTT (mtHTT and wild-type HTT (wtHTT mRNA and RNase H cleavage intensities, and patterns are investigated. This study profiled five different fluorinated nucleotides and showed them to have predictable, site-specific effects on RNase H cleavage, and the cleavage patterns were rationalized from a published X-ray structure of human RNase H1. The results herein can be used as a guide for future projects where ASO discrimination of SNPs is important.

Learning from Online Modules in Diverse Instructional Contexts

Directory of Open Access Journals (Sweden)

Gwen Nugent

2016-06-01

Full Text Available Learning objects originally developed for use in online learning environments can also be used to enhance face-to-face instruction. This study examined the learning impacts of online learning objects packaged into modules and used in different contexts for undergraduate education offered on campus at three institutions. A multi-case study approach was used, examining learning impacts across a variety of course subjects, course levels (introductory and advanced undergraduate, student levels (undergraduate and graduate, and instructional goals (i.e., replacement for lecture, remediation. A repeated measures design was used, with learning data collected prior to viewing the online module, after completion of the module, and at the end of the semester. The study provided a broad examination of ways that online modules are typically used in a college classroom, as well as measured learning effectiveness based on different instructional purpose and usage contexts. Results showed the effectiveness of the modules in serving as a substitute for classroom lecture, remediation of course prerequisite material, introduction to content with follow-up lab practice, and review for final exams. In each of these cases, the use of the modules resulted in significant learning increases, as well as retention of the learning until the end of the semester.

ES 1010 software for testing CAMAC modules

International Nuclear Information System (INIS)

Ableev, V.G.; Basiladze, S.G.; Zaporozhets, S.A.; Piskunov, N.M.; Ryabtsov, V.D.; Sitnik, I.M.; Strokovskij, E.A.; Sharov, V.I.

1977-01-01

Test programs for digital and analog-digital CAMAC modules applied in physical experiments are described. Algorithms were written in FORTRAN-4 language for testing, data acquisition, processing and data control. ASSEMBLER ES 1010 subroutines were used for data acquisition and CAMAC module control. This allowed one to take advantages of a high level language for data processing and display, as well as for achieving an interface with the CAMAC hardware. Software applied enables one to improve considerably adjustment of CAMAC modules and to obtain their operational characteristics

p-Type MWT. Integrated cell and module technology

Energy Technology Data Exchange (ETDEWEB)

Tool, C.J.J.; Kossen, E.J.; Bennett, I.J.

2013-10-15

A major issue of concern in MWT solar cells is the increased leakage current at reversed bias voltage through the vias compared. At ECN we have been working on reducing this leakage current to levels comparable to H-pattern cells. In this study we present the results of this work. We further show the benefit of a combined cell and module design for MWT solar cells. At the cell level, MWT production costs per wafer are comparable with H-pattern while the cell output increases. At the module level this design results in a further increase of the power output.

p-type MWT. Integrated Cell and Module Technology

Energy Technology Data Exchange (ETDEWEB)

Tool, C.J.J.; Kossen, E.J.; Bennett, I.J. [ECN Solar Energy, Petten (Netherlands)

2013-03-15

A major issue of concern in MWT (metal wrap-through) solar cells is the increased leakage current at reversed bias voltage through the vias compared. At ECN we have been working on reducing this leakage current to levels comparable to H-pattern cells. In this study we present the results of this work. We further show the benefit of a combined cell and module design for MWT solar cells. At the cell level, MWT production costs per wafer are comparable with H-pattern while the cell output increases. At the module level this design results in a further increase of the power output.

Interaction of a common painkiller piroxicam and copper-piroxicam with chromatin causes structural alterations accompanied by modulation at the epigenomic/genomic level.

Science.gov (United States)

Goswami, Sathi; Sanyal, Sulagna; Chakraborty, Payal; Das, Chandrima; Sarkar, Munna

2017-08-01

NSAIDs are the most common class of painkillers and anti-inflammatory agents. They also show other functions like chemoprevention and chemosuppression for which they act at the protein but not at the genome level since they are mostly anions at physiological pH, which prohibit their approach to the poly-anionic DNA. Complexing the drugs with bioactive metal obliterate their negative charge and allow them to bind to the DNA, thereby, opening the possibility of genome level interaction. To test this hypothesis, we present the interaction of a traditional NSAID, Piroxicam and its copper complex with core histone and chromatin. Spectroscopy, DLS, and SEM studies were applied to see the effect of the interaction on the structure of histone/chromatin. This was coupled with MTT assay, immunoblot analysis, confocal microscopy, micro array analysis and qRT-PCR. The interaction of Piroxicam and its copper complex with histone/chromatin results in structural alterations. Such structural alterations can have different biological manifestations, but to test our hypothesis, we have focused only on the accompanied modulations at the epigenomic/genomic level. The complex, showed alteration of key epigenetic signatures implicated in transcription in the global context, although Piroxicam caused no significant changes. We have correlated such alterations caused by the complex with the changes in global gene expression and validated the candidate gene expression alterations. Our results provide the proof of concept that DNA binding ability of the copper complexes of a traditional NSAID, opens up the possibility of modulations at the epigenomic/genomic level. Copyright © 2017 Elsevier B.V. All rights reserved.

Photovoltaic module and interlocked stack of photovoltaic modules

Science.gov (United States)

Wares, Brian S.

2014-09-02

One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame. A plurality of individual male alignment features and a plurality of individual female alignment features are included on each frame. Adjacent photovoltaic modules are interlocked by multiple individual male alignment features on a first module of the adjacent photovoltaic modules fitting into and being surrounded by corresponding individual female alignment features on a second module of the adjacent photovoltaic modules. Other embodiments, features and aspects are also disclosed.

Effect of modulation p-doping level on multi-state lasing in InAs/InGaAs quantum dot lasers having different external loss

Science.gov (United States)

Korenev, V. V.; Savelyev, A. V.; Maximov, M. V.; Zubov, F. I.; Shernyakov, Yu. M.; Kulagina, M. M.; Zhukov, A. E.

2017-09-01

The influence of the modulation p-doping level on multi-state lasing in InAs/InGaAs quantum dot (QD) lasers is studied experimentally for devices having various external losses. It is shown that in the case of short cavities (high external loss), there is an increase in the lasing power component corresponding to the ground-state optical transitions of QDs as the p-doping level grows. However, in the case of long cavities (small external loss), higher dopant concentrations may have an opposite effect on the output power. Based on these observations, an optimal design of laser geometry and an optimal doping level are discussed.

Design and Modeling a New Optical Modulator

Directory of Open Access Journals (Sweden)

Mohammad MEZAAEL

2009-06-01

Full Text Available A new opt modulator device using a Silicon Schottky Photodiode Device (s.s.p.d is proposed. The s.s.p.d. is fabricated in laboratory and has been used to mix an intensity modulated laser beam with a high frequency. The effects of modulating the high frequency signal before mixing on the photovoltage enhancement of the s.s.p.d is studied. A significant reduction in the required drive level of the high frequency input signal was achieved. Such a mixer could be use in radar and other communication systems.

Travel and Tourism Module. An Advanced-Level Option For Distribution and Marketing.

Science.gov (United States)

New York State Education Dept., Albany. Bureau of Occupational Education Curriculum Development.

Intended as an advanced option for distributive education students in the twelfth grade, this travel and tourism module is designed to cover a minimum of ten weeks or a maximum of twenty weeks. Introductory material includes information on employment demands, administrative considerations, course format, teaching suggestions, expected outcomes,…

Cell shunt resistance and photovoltaic module performance

Energy Technology Data Exchange (ETDEWEB)

McMahon, T.J.; Basso, T.S.; Rummel, S.R. [National Renewable Energy Lab., Golden, CO (United States)

1996-05-01

Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, the authors verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. The authors discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

Mass Spectrometry Analysis of Wild-Type and Knock-in Q140/Q140 Huntington's Disease Mouse Brains Reveals Changes in Glycerophospholipids Including Alterations in Phosphatidic Acid and Lyso-Phosphatidic Acid.

Science.gov (United States)

Vodicka, Petr; Mo, Shunyan; Tousley, Adelaide; Green, Karin M; Sapp, Ellen; Iuliano, Maria; Sadri-Vakili, Ghazaleh; Shaffer, Scott A; Aronin, Neil; DiFiglia, Marian; Kegel-Gleason, Kimberly B

2015-01-01

Huntington's disease (HD) is a neurodegenerative disease caused by a CAG expansion in the HD gene, which encodes the protein Huntingtin. Huntingtin associates with membranes and can interact directly with glycerophospholipids in membranes. We analyzed glycerophospholipid profiles from brains of 11 month old wild-type (WT) and Q140/Q140 HD knock-in mice to assess potential changes in glycerophospholipid metabolism. Polar lipids from cerebellum, cortex, and striatum were extracted and analyzed by liquid chromatography and negative ion electrospray tandem mass spectrometry analysis (LC-MS/MS). Gene products involved in polar lipid metabolism were studied using western blotting, immuno-electron microscopy and qPCR. Significant changes in numerous species of glycerophosphate (phosphatidic acid, PA) were found in striatum, cerebellum and cortex from Q140/Q140 HD mice compared to WT mice at 11 months. Changes in specific species could also be detected for other glycerophospholipids. Increases in species of lyso-PA (LPA) were measured in striatum of Q140/Q140 HD mice compared to WT. Protein levels for c-terminal binding protein 1 (CtBP1), a regulator of PA biosynthesis, were reduced in striatal synaptosomes from HD mice compared to wild-type at 6 and 12 months. Immunoreactivity for CtBP1 was detected on membranes of synaptic vesicles in striatal axon terminals in the globus pallidus. These novel results identify a potential site of molecular pathology caused by mutant Huntingtin that may impart early changes in HD.

Trace levels of innate immune response modulating impurities (IIRMIs synergize to break tolerance to therapeutic proteins.

Directory of Open Access Journals (Sweden)

Daniela Verthelyi

Full Text Available Therapeutic proteins such as monoclonal antibodies, replacement enzymes and toxins have significantly improved the therapeutic options for multiple diseases, including cancer and inflammatory diseases as well as enzyme deficiencies and inborn errors of metabolism. However, immune responses to these products are frequent and can seriously impact their safety and efficacy. Of the many factors that can impact protein immunogenicity, this study focuses on the role of innate immune response modulating impurities (IIRMIs that could be present despite product purification and whether these impurities can synergize to facilitate an immunogenic response to therapeutic proteins. Using lipopolysaccharide (LPS and CpG ODN as IIRMIs we showed that trace levels of these impurities synergized to induce IgM, IFNγ, TNFα and IL-6 expression. In vivo, trace levels of these impurities synergized to increase antigen-specific IgG antibodies to ovalbumin. Further, whereas mice treated with human erythropoietin showed a transient increase in hematocrit, those that received human erythropoietin containing low levels of IIRMIs had reduced response to erythropoietin after the 1(st dose and developed long-lasting anemia following subsequent doses. This suggests that the presence of IIRMIs facilitated a breach in tolerance to the endogenous mouse erythropoietin. Overall, these studies indicate that the risk of enhancing immunogenicity should be considered when establishing acceptance limits of IIRMIs for therapeutic proteins.

Trace levels of innate immune response modulating impurities (IIRMIs) synergize to break tolerance to therapeutic proteins.

Science.gov (United States)

Verthelyi, Daniela; Wang, Vivian

2010-12-22

Therapeutic proteins such as monoclonal antibodies, replacement enzymes and toxins have significantly improved the therapeutic options for multiple diseases, including cancer and inflammatory diseases as well as enzyme deficiencies and inborn errors of metabolism. However, immune responses to these products are frequent and can seriously impact their safety and efficacy. Of the many factors that can impact protein immunogenicity, this study focuses on the role of innate immune response modulating impurities (IIRMIs) that could be present despite product purification and whether these impurities can synergize to facilitate an immunogenic response to therapeutic proteins. Using lipopolysaccharide (LPS) and CpG ODN as IIRMIs we showed that trace levels of these impurities synergized to induce IgM, IFNγ, TNFα and IL-6 expression. In vivo, trace levels of these impurities synergized to increase antigen-specific IgG antibodies to ovalbumin. Further, whereas mice treated with human erythropoietin showed a transient increase in hematocrit, those that received human erythropoietin containing low levels of IIRMIs had reduced response to erythropoietin after the 1(st) dose and developed long-lasting anemia following subsequent doses. This suggests that the presence of IIRMIs facilitated a breach in tolerance to the endogenous mouse erythropoietin. Overall, these studies indicate that the risk of enhancing immunogenicity should be considered when establishing acceptance limits of IIRMIs for therapeutic proteins.

Weyl modules, demazure modules, KR-modules, crystals, fusion products and limit constructions

OpenAIRE

Fourier, G.; Littelmann, P.

2007-01-01

We study finite dimensional representations of current algebras, loop algebras and their quantized versions. For the current algebra of a simple Lie algebra of type {\\tt ADE}, we show that Kirillov-Reshetikhin modules and Weyl modules are in fact all Demazure modules. As a consequence one obtains an elementary proof of the dimension formula for Weyl modules for the current and the loop algebra. Further, we show that the crystals of the Weyl and the Demazure module are the same up to some addi...

Effects of periodic modulation on the nonlinear Landau–Zener tunneling

International Nuclear Information System (INIS)

Li-Hua, Wu; Wen-Shan, Duan

2009-01-01

We study the Landau–Zener tunneling of a nonlinear two-level system by applying a periodic modulation on its energy bias. We find that the two levels are splitting at the zero points of the zero order Bessel function for high-frequency modulation. Moreover, we obtain the effective coupling constant between two levels at the zero points of the zero order Bessel function by calculating the final tunneling probability at these points. It seems that the effective coupling constant can be regarded as the approximation of the higher order Bessel function at these points. For the low-frequency modulation, we find that the final tunneling probability is a function of the interaction strength. For the weak inter-level coupling case, we find that the final tunneling probability is more disordered as the interaction strength becomes larger. (general)

Superstability for Generalized Module Left Derivations and Generalized Module Derivations on a Banach Module (I

Directory of Open Access Journals (Sweden)

Rassias JM

2009-01-01

Full Text Available We discuss the superstability of generalized module left derivations and generalized module derivations on a Banach module. Let be a Banach algebra and a Banach -module, and . The mappings , and are defined and it is proved that if (resp., is dominated by then is a generalized (resp., linear module- left derivation and is a (resp., linear module- left derivation. It is also shown that if (resp., is dominated by then is a generalized (resp., linear module- derivation and is a (resp., linear module- derivation.

Subsecond Sensory Modulation of Serotonin Levels in a Primary Sensory Area and Its Relation to Ongoing Communication Behavior in a Weakly Electric Fish.

Science.gov (United States)

Fotowat, Haleh; Harvey-Girard, Erik; Cheer, Joseph F; Krahe, Rüdiger; Maler, Leonard

2016-01-01

Serotonergic neurons of the raphe nuclei of vertebrates project to most regions of the brain and are known to significantly affect sensory processing. The subsecond dynamics of sensory modulation of serotonin levels and its relation to behavior, however, remain unknown. We used fast-scan cyclic voltammetry to measure serotonin release in the electrosensory system of weakly electric fish, Apteronotus leptorhynchus . These fish use an electric organ to generate a quasi-sinusoidal electric field for communicating with conspecifics. In response to conspecific signals, they frequently produce signal modulations called chirps. We measured changes in serotonin concentration in the hindbrain electrosensory lobe (ELL) with a resolution of 0.1 s concurrently with chirping behavior evoked by mimics of conspecific electric signals. We show that serotonin release can occur phase locked to stimulus onset as well as spontaneously in the ELL region responsible for processing these signals. Intense auditory stimuli, on the other hand, do not modulate serotonin levels in this region, suggesting modality specificity. We found no significant correlation between serotonin release and chirp production on a trial-by-trial basis. However, on average, in the trials where the fish chirped, there was a reduction in serotonin release in response to stimuli mimicking similar-sized same-sex conspecifics. We hypothesize that the serotonergic system is part of an intricate sensory-motor loop: serotonin release in a sensory area is triggered by sensory input, giving rise to motor output, which can in turn affect serotonin release at the timescale of the ongoing sensory experience and in a context-dependent manner.

Klystron Gun Arcing and Modulator Protection

International Nuclear Information System (INIS)

Gold, S

2004-01-01

The demand for 500 kV and 265 amperes peak to power an X-Band klystron brings up protection issues for klystron faults and the energy dumped into the arc from the modulator. This situation is made worse when more than one klystron will be driven from a single modulator, such as the existing schemes for running two and eight klystrons. High power pulsed klystrons have traditionally be powered by line type modulators which match the driving impedance with the load impedance and therefore current limit at twice the operating current. Multiple klystrons have the added problems of a lower modulator source impedance and added stray capacitance, which converts into appreciable energy at high voltages like 500kV. SLAC has measured the energy dumped into klystron arcs in a single and dual klystron configuration at the 400 to 450 kV level and found interesting characteristics in the arc formation. The author will present measured data from klystron arcs powered from line-type modulators in several configurations. The questions arise as to how the newly designed solid-state modulators, running multiple tubes, will react to a klystron arc and how much energy will be dumped into the arc

Neuro-cognitive mechanisms underlying the emotional modulation of word reading

Institute of Scientific and Technical Information of China (English)

无

2006-01-01

A novel neural model for emotional modulation of word reading is proposed. This model has four principal hypotheses: the dominant activation region hypothesis, the emotional modulation hypothesis, the attentional level hypothesis, and the interaction hypothesis. Four lines of research were reviewed to provide evidence for these hypotheses: (1) neuro-cognitive studies on the mechanisms of word reading (i.e., neural networks for reading); (2) studies on the influence of words' emotional valence on word reading; (3) studies of the effect of attention on word reading; and (4) studies on emotional modulation of word reading under different attentional levels.

dNTP pool levels modulate mutator phenotypes of error-prone DNA polymerase ε variants.

Science.gov (United States)

Williams, Lindsey N; Marjavaara, Lisette; Knowels, Gary M; Schultz, Eric M; Fox, Edward J; Chabes, Andrei; Herr, Alan J

2015-05-12

Mutator phenotypes create genetic diversity that fuels tumor evolution. DNA polymerase (Pol) ε mediates leading strand DNA replication. Proofreading defects in this enzyme drive a number of human malignancies. Here, using budding yeast, we show that mutator variants of Pol ε depend on damage uninducible (Dun)1, an S-phase checkpoint kinase that maintains dNTP levels during a normal cell cycle and up-regulates dNTP synthesis upon checkpoint activation. Deletion of DUN1 (dun1Δ) suppresses the mutator phenotype of pol2-4 (encoding Pol ε proofreading deficiency) and is synthetically lethal with pol2-M644G (encoding altered Pol ε base selectivity). Although pol2-4 cells cycle normally, pol2-M644G cells progress slowly through S-phase. The pol2-M644G cells tolerate deletions of mediator of the replication checkpoint (MRC) 1 (mrc1Δ) and radiation sensitive (Rad) 9 (rad9Δ), which encode mediators of checkpoint responses to replication stress and DNA damage, respectively. The pol2-M644G mutator phenotype is partially suppressed by mrc1Δ but not rad9Δ; neither deletion suppresses the pol2-4 mutator phenotype. Thus, checkpoint activation augments the Dun1 effect on replication fidelity but is not required for it. Deletions of genes encoding key Dun1 targets that negatively regulate dNTP synthesis, suppress the dun1Δ pol2-M644G synthetic lethality and restore the mutator phenotype of pol2-4 in dun1Δ cells. DUN1 pol2-M644G cells have constitutively high dNTP levels, consistent with checkpoint activation. In contrast, pol2-4 and POL2 cells have similar dNTP levels, which decline in the absence of Dun1 and rise in the absence of the negative regulators of dNTP synthesis. Thus, dNTP pool levels correlate with Pol ε mutator severity, suggesting that treatments targeting dNTP pools could modulate mutator phenotypes for therapy.

Tuning of Human Modulation Filters Is Carrier-Frequency Dependent

Science.gov (United States)

Simpson, Andrew J. R.; Reiss, Joshua D.; McAlpine, David

2013-01-01

Recent studies employing speech stimuli to investigate ‘cocktail-party’ listening have focused on entrainment of cortical activity to modulations at syllabic (5 Hz) and phonemic (20 Hz) rates. The data suggest that cortical modulation filters (CMFs) are dependent on the sound-frequency channel in which modulations are conveyed, potentially underpinning a strategy for separating speech from background noise. Here, we characterize modulation filters in human listeners using a novel behavioral method. Within an ‘inverted’ adaptive forced-choice increment detection task, listening level was varied whilst contrast was held constant for ramped increments with effective modulation rates between 0.5 and 33 Hz. Our data suggest that modulation filters are tonotopically organized (i.e., vary along the primary, frequency-organized, dimension). This suggests that the human auditory system is optimized to track rapid (phonemic) modulations at high sound-frequencies and slow (prosodic/syllabic) modulations at low frequencies. PMID:24009759

Highly dissipative Hénon map behavior in the four-level model of the CO 2 laser with modulated losses

Science.gov (United States)

Pando L., C. L.; Acosta, G. A. Luna; Meucci, R.; Ciofini, M.

1995-02-01

We show that the four-level model for the CO 2 laser with modulated losses behaves in a qualitatively similar way as the highly dissipative Hénon map. The ubiquity of elements of the universal sequence, their related symbolic dynamics, and the presence of reverse bifurcations of chaotic bands in the model are reminiscent of the logistic map which is the limit of the Hénon map when the Jacobian equals zero. The coexistence of attractors, its dynamics related to contraction of volumes in phase space and the associated return maps can be correlated with those of the highly dissipative Hénon map.

Circuit analysis method for thin-film solar cell modules

Science.gov (United States)

Burger, D. R.

1985-01-01

The design of a thin-film solar cell module is dependent on the probability of occurrence of pinhole shunt defects. Using known or assumed defect density data, dichotomous population statistics can be used to calculate the number of defects expected in a module. Probability theory is then used to assign the defective cells to individual strings in a selected series-parallel circuit design. Iterative numerical calculation is used to calcuate I-V curves using cell test values or assumed defective cell values as inputs. Good and shunted cell I-V curves are added to determine the module output power and I-V curve. Different levels of shunt resistance can be selected to model different defect levels.

Enhanced mutual capture of colored solitons by matched modulator

Science.gov (United States)

Feigenbaum, Eyal; Orenstein, Meir

2004-08-01

The mutual capture of two colored solitons is enhanced by a modulator, to a level which enables its practical exploitation, e.g., for a read- write mechanism in a soliton buffer. The enhanced capture was analyzed using closed form particle-like soliton perturbation, and verified by numerical simulations. Optimal modulator frequency and modulation depth are obtained. This mutual capture can be utilized for all-optical soliton logic and memory.

Modulation in vitro and in vivo of cytotoxicity but not cellular levels of doxorubicin by the calmodulin inhibitor trifluoperazine is dependent on the level of resistance.

Science.gov (United States)

Ganapathi, R.; Schmidt, H.; Grabowski, D.; Melia, M.; Ratliff, N.

1988-01-01

The role of the calmodulin inhibitor trifluoperazine (TFP) in modulating the cellular levels and cytotoxicity in vitro and antitumour effects in vivo of doxorubicin (DOX), was evaluated in progressively DOX-resistant (5- to 40-fold) sublines of B16-BL6 mouse melanoma. In parental-sensitive B16-BL6 cells treated for 3 h, the IC50 of DOX was 0.1 microgram ml-1, and a less than 2-fold enhancement in DOX cell kill in the presence of a noncytotoxic concentration of 5 microM TFP was observed. However, in the DOX-resistant sublines, the IC50 was 0.7 to 5.0 micrograms ml-1 DOX in the absence of 5 microM TFP and 0.3 to 0.7 microgram ml-1 DOX in the presence of 5 microM TFP. The 2- to 7.5-fold decrease in the IC50 of DOX in the presence of 5 microM TFP, was dependent on the level of DOX-resistance in the various sublines. Compared to parental-sensitive cells, a 2-fold decrease in DOX-accumulation was evident only in the 40-fold DOX-resistant subline. Further, maximal enhancement (50%) of cellular DOX accumulation in the presence of 5 microM TFP was observed only in the 40-fold resistant cells treated with 5.0 micrograms ml-1 DOX. Retention of DOX in the 40-fold resistant subline was only 20% lower than similarly treated sensitive cells, and the inclusion of TFP increased DOX retention less than 10-15%. Antitumour studies in mice with experimental pulmonary metastases revealed that although DOX and DOX plus TFP had similar antitumour activity with the parental sensitive B16-BL6 cells, the combination of DOX plus TFP was significantly more effective than DOX alone with the DOX-resistant sublines. No overt toxicity was observed in normal mice treated with doses of TFP, DOX or DOX plus TFP used for in vivo chemotherapy studies. Results from this study suggest that gross cellular DOX levels do not appear to correlate with the magnitude of resistance, and the effects of TFP in modulating DOX resistance is possibly due to mechanisms other than mere alterations in cellular drug

Occupational Home Economics Education Series. Catering Services. Competency Based Teaching Module.

Science.gov (United States)

Lowe, Phyllis; And Others

This module, one of ten competency based modules developed for vocational home economics teachers, is based on a job cluster in the catering industry. It is designed for use with a variety of levels of learners (secondary, postsecondary, adult) in both school and non-school educational settings. Focusing on two levels of employment, food caterer…

Reduction in mitochondrial DNA copy number in peripheral leukocytes after onset of Huntington's disease

DEFF Research Database (Denmark)

Petersen, Maria Hvidberg; Budtz-Jørgensen, Esben; Sørensen, Sven Asger

2014-01-01

Huntington's disease (HD) is an inherited neurodegenerative disorder characterised by movement disorder, cognitive symptoms and psychiatric symptoms with predominantly adult-onset. The mutant huntingtin protein leads to mitochondrial dysfunction in blood leukocytes. This discovery led to the inve......Huntington's disease (HD) is an inherited neurodegenerative disorder characterised by movement disorder, cognitive symptoms and psychiatric symptoms with predominantly adult-onset. The mutant huntingtin protein leads to mitochondrial dysfunction in blood leukocytes. This discovery led...

Exploring Local Level Factors Shaping the Implementation of a Blended Learning Module for Information and Geospatial Literacy in Ontario

Directory of Open Access Journals (Sweden)

Michelle M. Vine

2016-12-01

Full Text Available The objectives of this research study were to examine local level factors shaping the implementation of a blended pedagogical approach for geospatial- and information-literacy, and to understand implementer satisfaction. As such, we addressed the following research questions: What local-level factors shape the implementation of the blended learning model? and How satisfied are implementers (faculty, administrators and library instructional/support staff with the new blended learning model for geospatial and information fluency? Focus groups (n=7 plus one interview (total n=22 were conducted with key stakeholders (e.g., staff, faculty, administrators to better understand facilitators, barriers, and/or issues related to module development, in addition to perceptions about how the modules are utilized by teaching assistants (TAs, instructional assistants (IAs, and instructors. Participants were identified according to their status as either discipline-specific instructional staff (i.e., instructor, TA, IA or staff who supported the development of modules (i.e., library instructional staff, library management, administrators. From an ontological standpoint that privileges an individual perspective on the nature of reality, while epistemologically seeking to understand the relationship between the “knower” and what can be known, we adopted a theory of constructivism to support this inquiry. Transcripts were imported into a qualitative analysis software package (NVivo 8.0 for organization, coding and analysis. Instructors found value in the online modules, particularly in a blended learning setting. Instructors felt that having the material in advance, in-class time could be better focused on interaction, assignments, and assessments and resulted in reduced anxiety in busy lab environments. Several key themes emerged, including: (a instructor expectations (time constraints, sustainability, and collaborative nature of development process and

Modulation of systemic immune responses through commensal gastrointestinal microbiota.

Directory of Open Access Journals (Sweden)

Kyle M Schachtschneider

Full Text Available Colonization of the gastrointestinal (GI tract is initiated during birth and continually seeded from the individual's environment. Gastrointestinal microorganisms play a central role in developing and modulating host immune responses and have been the subject of investigation over the last decades. Animal studies have demonstrated the impact of GI tract microbiota on local gastrointestinal immune responses; however, the full spectrum of action of early gastrointestinal tract stimulation and subsequent modulation of systemic immune responses is poorly understood. This study explored the utility of an oral microbial inoculum as a therapeutic tool to affect porcine systemic immune responses. For this study a litter of 12 pigs was split into two groups. One group of pigs was inoculated with a non-pathogenic oral inoculum (modulated, while another group (control was not. DNA extracted from nasal swabs and fecal samples collected throughout the study was sequenced to determine the effects of the oral inoculation on GI and respiratory microbial communities. The effects of GI microbial modulation on systemic immune responses were evaluated by experimentally infecting with the pathogen Mycoplasma hyopneumoniae. Coughing levels, pathology, toll-like receptors 2 and 6, and cytokine production were measured throughout the study. Sequencing results show a successful modulation of the GI and respiratory microbiomes through oral inoculation. Delayed type hypersensitivity responses were stronger (p = 0.07, and the average coughing levels and respiratory TNF-α variance were significantly lower in the modulated group (p<0.0001 and p = 0.0153, respectively. The M. hyopneumoniae infection study showed beneficial effects of the oral inoculum on systemic immune responses including antibody production, severity of infection and cytokine levels. These results suggest that an oral microbial inoculation can be used to modulate microbial communities, as well as

Solid-State Modulators for RF And Fast Kickers

Energy Technology Data Exchange (ETDEWEB)

Cook, E.G.; Akana, G.L.; Gower, E.J.; Hawkins, S.A.; Hickman, B.C.; /LLNL, Livermore; Brooksby, C.A.; /NONE - BECHTEL NEVADA LAS VEGAS; Cassel, R.L.; de Lamare, J.E.; Nguyen, M.N.; Pappas, G.C.; /SLAC

2006-03-14

As the switching capabilities of solid-state devices increase, these devices are being incorporated into modulator designs for high voltage accelerator applications. Solid-state modulators based on inductive adder circuit topology have demonstrated great versatility with regard to pulse width and pulse repetition rate while maintaining fast pulse rise and fall times. Additionally, these modulators are capable of being scaled to higher output voltage and power levels. An explanation of the basic circuit operation will be presented as well as test data of several different hardware systems.

SOLID-STATE MODULATORS FOR RF AND FAST KICKERS

International Nuclear Information System (INIS)

Cook, E G; Akana, G; Gower, E J; Hawkins, S A; Hickman, B C; Brooksby, C A; Cassel, R L; De Lamare, J E; Nguyen, M N; Pappas, G C

2005-01-01

As the switching capabilities of solid-state devices increase, these devices are being incorporated into modulator designs for high voltage accelerator applications. Solid-state modulators based on inductive adder circuit topology have demonstrated great versatility with regard to pulse width and pulse repetition rate while maintaining fast pulse rise and fall times. Additionally, these modulators are capable of being scaled to higher output voltage and power levels. An explanation of the basic circuit operation will be presented as well as test data of several different hardware systems

SOLID-STATE MODULATORS FOR RF AND FAST KICKERS

Energy Technology Data Exchange (ETDEWEB)

Cook, E G; Akana, G; Gower, E J; Hawkins, S A; Hickman, B C; Brooksby, C A; Cassel, R L; De Lamare, J E; Nguyen, M N; Pappas, G C

2005-05-05

As the switching capabilities of solid-state devices increase, these devices are being incorporated into modulator designs for high voltage accelerator applications. Solid-state modulators based on inductive adder circuit topology have demonstrated great versatility with regard to pulse width and pulse repetition rate while maintaining fast pulse rise and fall times. Additionally, these modulators are capable of being scaled to higher output voltage and power levels. An explanation of the basic circuit operation will be presented as well as test data of several different hardware systems.

Solid-State Modulators for RF and Fast Kickers

CERN Document Server

Cook, Edward; Brooksby, Craig A; Cassel, Richard; De Lamare, Jeffrey E; Gower, Edward J; Hawkins, Steven; Hickman, Bradley C; Nguyen, Minh N; Pappas, Chris

2005-01-01

As the capabilities of solid-state devices increase, these devices are being incorporated into modulator designs for high voltage accelerator applications. Solid-state modulators based on inductive adder circuit topology have demonstrated great versatility with regard to pulse width and pulse repetition rate while maintaining fast pulse rise and fall times. Additionally, these modulators are capable of being scaled to higher output voltage and power levels. An explanation of the basic circuit operation will be presented as well as test data of several different hardware systems.

Current level detector

International Nuclear Information System (INIS)

Kerns, C.R.

1977-01-01

A device is provided for detecting the current level of a dc signal. It includes an even harmonic modulator to which a reference ac signal is applied. The unknown dc signal acts on the reference ac signal so that the output of the modulator includes an even harmonic whose amplitude is proportional to the unknown dc current. The device may be used to provide overcurrent protection for proportional wire chambers

Phase ramping and modulation of reflectometer signals

International Nuclear Information System (INIS)

Conway, G.D.; Bartlett, D.V.; Stoff, P.E.

1999-01-01

The phase and amplitude signals of JET heterodyne reflectometers show varying levels of high frequency turbulence superimposed on a slow changing mean. The phase signal also shows multi-radian (> 1 fringe) variations with two quite different time scales (2-10 ms and sub-ms). In both cases the mean reflected power, together with turbulent phase and amplitude fluctuation levels, are modulated synchronously with the are modulated synchronously with the phase fringes. The slow fringes appear to result radial movement of the cutoff layer with the amplitude modulation possibly due to multiple reflection between plasma and wall. The fast fringes occur in intermittent bursts and appear to be phase runaway resulting from antenna misalignment. Using a 2-D physical optics simulation code it is possible to replicate the fast bursts of phase runaway from steady-state turbulence and misaligned antennas. This offers a possible alternative explanation for some of the observations of bursting turbulence seen in reflectometer signals. (authors)

Modulator-free quadrature amplitude modulation signal synthesis

Science.gov (United States)

Liu, Zhixin; Kakande, Joseph; Kelly, Brian; O'Carroll, John; Phelan, Richard; Richardson, David J.; Slavík, Radan

2014-12-01

The ability to generate high-speed on-off-keyed telecommunication signals by directly modulating a semiconductor laser’s drive current was one of the most exciting prospective applications of the nascent field of laser technology throughout the 1960s. Three decades of progress led to the commercialization of 2.5 Gbit s-1-per-channel submarine fibre optic systems that drove the growth of the internet as a global phenomenon. However, the detrimental frequency chirp associated with direct modulation forced industry to use external electro-optic modulators to deliver the next generation of on-off-keyed 10 Gbit s-1 systems and is absolutely prohibitive for today’s (>)100 Gbit s-1 coherent systems, which use complex modulation formats (for example, quadrature amplitude modulation). Here we use optical injection locking of directly modulated semiconductor lasers to generate complex modulation format signals showing distinct advantages over current and other currently researched solutions.

Attention modulates visual size adaptation.

Science.gov (United States)

Kreutzer, Sylvia; Fink, Gereon R; Weidner, Ralph

2015-01-01

The current study determined in healthy subjects (n = 16) whether size adaptation occurs at early, i.e., preattentive, levels of processing or whether higher cognitive processes such as attention can modulate the illusion. To investigate this issue, bottom-up stimulation was kept constant across conditions by using a single adaptation display containing both small and large adapter stimuli. Subjects' attention was directed to either the large or small adapter stimulus by means of a luminance detection task. When attention was directed toward the small as compared to the large adapter, the perceived size of the subsequent target was significantly increased. Data suggest that different size adaptation effects can be induced by one and the same stimulus depending on the current allocation of attention. This indicates that size adaptation is subject to attentional modulation. These findings are in line with previous research showing that transient as well as sustained attention modulates visual features, such as contrast sensitivity and spatial frequency, and influences adaptation in other contexts, such as motion adaptation (Alais & Blake, 1999; Lankheet & Verstraten, 1995). Based on a recently suggested model (Pooresmaeili, Arrighi, Biagi, & Morrone, 2013), according to which perceptual adaptation is based on local excitation and inhibition in V1, we conclude that guiding attention can boost these local processes in one or the other direction by increasing the weight of the attended adapter. In sum, perceptual adaptation, although reflected in changes of neural activity at early levels (as shown in the aforementioned study), is nevertheless subject to higher-order modulation.

What Factors Promote Student Resilience on a Level 1 Distance Learning Module?

Science.gov (United States)

Simons, Joan; Beaumont, Kythe; Holland, Lesley

2018-01-01

Resilience is understood to be the ability to adapt positively in the face of adversity. In relation to new students on a distance learning module, this can mean how they adapt and make sense of the demands of their chosen study to enable them to persist in their studies. This article reports a small-scale study involving semi-structured telephone…

Beam Test of the ATLAS Level-1 Calorimeter Trigger System

CERN Document Server

Garvey, J; Mahout, G; Moye, T H; Staley, R J; Thomas, J P; Typaldos, D; Watkins, P M; Watson, A; Achenbach, R; Föhlisch, F; Geweniger, C; Hanke, P; Kluge, E E; Mahboubi, K; Meier, K; Meshkov, P; Rühr, F; Schmitt, K; Schultz-Coulon, H C; Ay, C; Bauss, B; Belkin, A; Rieke, S; Schäfer, U; Tapprogge, T; Trefzger, T; Weber, GA; Eisenhandler, E F; Landon, M; Apostologlou, P; Barnett, B M; Brawn, I P; Davis, A O; Edwards, J; Gee, C N P; Gillman, A R; Mirea, A; Perera, V J O; Qian, W; Sankey, D P C; Bohm, C; Hellman, S; Hidvegi, A; Silverstein, S

2005-01-01

The Level-1 Calorimter Trigger consists of a Preprocessor (PP), a Cluster Processor (CP), and a Jet/Energy-sum Processor (JEP). The CP and JEP receive digitised trigger-tower data from the Preprocessor and produce Region-of-Interest (RoIs) and trigger multiplicities. The latter are sent in real time to the Central Trigger Processor (CTP) where the Level-1 decision is made. On receipt of a Level-1 Accept, Readout Driver Modules (RODs), provide intermediate results to the data acquisition (DAQ) system for monitoring and diagnostic purpose. RoI information is sent to the RoI builder (RoIB) to help reduce the amount of data required for the Level-2 Trigger The Level-1 Calorimeter Trigger System at the test beam consisted of 1 Preprocessor module, 1 Cluster Processor Module, 1 Jet/Energy Module and 2 Common Merger Modules. Calorimeter energies were sucessfully handled thourghout the chain and trigger object sent to the CTP. Level-1 Accepts were sucessfully produced and used to drive the readout path. Online diagno...

Suggestibility and suggestive modulation of the Stroop effect.

Science.gov (United States)

Kirsch, Irving

2011-06-01

Although the induction of a hypnotic state does not seem necessary for suggestive modulation of the Stroop effect, this important phenomenon has seemed to be dependent on the subject's level of hypnotic suggestibility. Raz and Campbell's (2011) study indicates that suggestion can modulate the Stroop effect substantially in very low suggestible subjects, as well as in those who are highly suggestible. This finding casts doubt on the presumed mechanism by which suggestive modulation is brought about. Research aimed at uncovering the means by which low suggestible individuals are able to modulate the Stroop effect would be welcome, as would assessment of this effect in moderately suggestible people. Copyright © 2010 Elsevier Inc. All rights reserved.

Medical Terminology: Latin Words/Abbreviations; Special Signs and Symbols. Health Occupations Education Module.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on medical terminology (using Latin words/abbreviations; special signs and symbols) is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module consists of an introduction to the module topic, a list of resources needed, and three…

Medical Terminology: Using Some Common Prefixes, Suffixes, and Roots. Health Occupations Education Module.

Science.gov (United States)

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on medical terminology (using common prefixes, suffixes, and root words) is one of 17 modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module consists of an introduction to the module topic, a list of resources needed, and three learning…

A-level Mathematics Options – Views of Secondary-level Teachers

OpenAIRE

Cole, Jonathan S.

2015-01-01

The A-level Mathematics qualification is based on a compulsory set of pure maths modules and a selection of applied maths modules with the pure maths representing two thirds of the assessment. The applied maths section includes mechanics, statistics and (sometimes) decision maths. A combination of mechanics and statistics tends to be the most popular choice by far. The current study aims to understand how maths teachers in secondary education make decisions regarding the curriculum options an...

Module-based structure design of wheeled mobile robot

Directory of Open Access Journals (Sweden)

Z. Luo

2018-02-01

Full Text Available This paper proposes an innovative and systematic approach for synthesizing mechanical structures of wheeled mobile robots. The principle and terminologies used for the proposed synthesis method are presented by adopting the concept of modular design, isomorphic and non-isomorphic, and set theory with its associated combinatorial mathematics. The modular-based innovative synthesis and design of wheeled robots were conducted at two levels. Firstly at the module level, by creative design and analysing the structures of classic wheeled robots, a wheel module set containing four types of wheel mechanisms, a suspension module set consisting of five types of suspension frames and a chassis module set composed of five types of rigid or articulated chassis were designed and generalized. Secondly at the synthesis level, two kinds of structure synthesis modes, namely the isomorphic-combination mode and the non-isomorphic combination mode were proposed to synthesize mechanical structures of wheeled robots; which led to 241 structures for wheeled mobile robots including 236 novel ones. Further, mathematical models and a software platform were developed to provide appropriate and intuitive tools for simulating and evaluating performance of the wheeled robots that were proposed in this paper. Eventually, physical prototypes of sample wheeled robots/rovers were developed and tested so as to prove and validate the principle and methodology presented in this paper.

Trainer module for security control center operations

International Nuclear Information System (INIS)

Bernard, E.A.

1982-01-01

An operator trainer module has been developed to be used with the security control center equipment to be installed as part of a safeguards physical protection system. The module is designed to provide improved training and testing capabilities for control center operators through the use of simulations for perimeter equipment operations. Operators, through the trainer module, can be challenged with a variety of realistic situations which require responsive action identical to that needed in an actual system. This permits a consistent evaluation and confirmation of operator capabilities prior to assignment as an operator and allows for periodic retesting to verify that adequate performance levels are maintained

A method for identifying hierarchical sub-networks / modules and weighting network links based on their similarity in sub-network / module affiliation

Directory of Open Access Journals (Sweden)

WenJun Zhang

2016-06-01

Full Text Available Some networks, including biological networks, consist of hierarchical sub-networks / modules. Based on my previous study, in present study a method for both identifying hierarchical sub-networks / modules and weighting network links is proposed. It is based on the cluster analysis in which between-node similarity in sets of adjacency nodes is used. Two matrices, linkWeightMat and linkClusterIDs, are achieved by using the algorithm. Two links with both the same weight in linkWeightMat and the same cluster ID in linkClusterIDs belong to the same sub-network / module. Two links with the same weight in linkWeightMat but different cluster IDs in linkClusterIDs belong to two sub-networks / modules at the same hirarchical level. However, a link with an unique cluster ID in linkClusterIDs does not belong to any sub-networks / modules. A sub-network / module of the greater weight is the more connected sub-network / modules. Matlab codes of the algorithm are presented.

Mechanism for iron control of the Vibrio fischeri luminescence system: involvement of cyclic AMP and cyclic AMP receptor protein and modulation of DNA level.

Science.gov (United States)

Dunlap, P V

1992-07-01

Iron controls luminescence in Vibrio fischeri by an indirect but undefined mechanism. To gain insight into that mechanism, the involvement of cyclic AMP (cAMP) and cAMP receptor protein (CRP) and of modulation of DNA levels in iron control of luminescence were examined in V. fischeri and in Escherichia coli containing the cloned V. fischeri lux genes on plasmids. For V. fischeri and E. coli adenylate cyclase (cya) and CRP (crp) mutants containing intact lux genes (luxR luxICDABEG), presence of the iron chelator ethylenediamine-di(o-hydroxyphenyl acetic acid) (EDDHA) increased expression of the luminescence system like in the parent strains only in the cya mutants in the presence of added cAMP. In the E. coli strains containing a plasmid with a Mu dl(lacZ) fusion in luxR, levels of beta-galactosidase activity (expression from the luxR promoter) and luciferase activity (expression from the lux operon promoter) were both 2-3-fold higher in the presence of EDDHA in the parent strain, and for the mutants this response to EDDHA was observed only in the cya mutant in the presence of added cAMP. Therefore, cAMP and CRP are required for the iron restriction effect on luminescence, and their involvement in iron control apparently is distinct from the known differential control of transcription from the luxR and luxICDABEG promoters by cAMP-CRP. Furthermore, plasmid and chromosomal DNA levels were higher in E. coli and V. fischeri in the presence of EDDHA. The higher DNA levels correlated with an increase in expression of chromosomally encoded beta-galactosidase in E. coli and with a higher level of autoinducer in cultures of V. fischeri. These results implicate cAMP-CRP and modulation of DNA levels in the mechanism of iron control of the V. fischeri luminescence system.

Demazure Modules, Fusion Products and Q-Systems

Science.gov (United States)

Chari, Vyjayanthi; Venkatesh, R.

2015-01-01

In this paper, we introduce a family of indecomposable finite-dimensional graded modules for the current algebra associated to a simple Lie algebra. These modules are indexed by an -tuple of partitions , where α varies over a set of positive roots of and we assume that they satisfy a natural compatibility condition. In the case when the are all rectangular, for instance, we prove that these modules are Demazure modules in various levels. As a consequence, we see that the defining relations of Demazure modules can be greatly simplified. We use this simplified presentation to relate our results to the fusion products, defined in (Feigin and Loktev in Am Math Soc Transl Ser (2) 194:61-79, 1999), of representations of the current algebra. We prove that the Q-system of (Hatayama et al. in Contemporary Mathematics, vol. 248, pp. 243-291. American Mathematical Society, Providence, 1998) extends to a canonical short exact sequence of fusion products of representations associated to certain special partitions .Finally, in the last section we deal with the case of and prove that the modules we define are just fusion products of irreducible representations of the associated current algebra and give monomial bases for these modules.

Photovoltaic module and interlocked stack of photovoltaic modules

Science.gov (United States)

Wares, Brian S.

2012-09-04

One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame having at least a top member and a bottom member. A plurality of alignment features are included on the top member of each frame, and a plurality of alignment features are included on the bottom member of each frame. Adjacent photovoltaic modules are interlocked by the alignment features on the top member of a lower module fitting together with the alignment features on the bottom member of an upper module. Other embodiments, features and aspects are also disclosed.

Detector Modules for the CMS Pixel Phase 1 Upgrade

CERN Document Server

Zhu, De Hua; Berger, Pirmin; Meinhard, Maren Tabea; Starodumov, Andrey; Tavolaro, Vittorio Raoul

2017-01-01

The CMS Pixel phase 1 upgrade detector consists of 1184 modules with new design. An important part of the production is the module qualification and calibration, ensuring their proper functionality within the detector. This paper summarizes the qualification and calibration results of modules used in the innermost two detector layers with focus on methods using module-internal calibration signals. Extended characterizations on pixel level such as electronic noise and bump bond connectivity, optimization of operational parameters, sensor quality and thermal stress resistance were performed using a customized setup with controlled environment. It could be shown that the selected modules have on average $0.55 \\mathrm{ {}^{0\\!}\\!/\\!_{00} }\\, \\pm \\, 0.01 \\mathrm{ {}^{0\\!}\\!/\\!_{00} }\\,$ defective pixels and that all performance parameters stay within their specifications.

Microfiltration of soy sauce sediment with rotating disk membrane module; Kaitengata enbanmaku module ni yoru shoyuori no roka

Energy Technology Data Exchange (ETDEWEB)

Matsushita, K.; Kanekuni, N.; Nogaki, H.; Itakura, I.; Shimizu, Y.; Watanabe, A. [TOTO Ltd., Kitakyushu (Japan)

1995-01-15

Soy sauce sediment is formed in pasteurization of raw soy sauce. It is treated as industrial waste, though its main component is soy sauce, because of difficulty in perfect clarification of the suspension. In this paper, we decided a suitable range of pore size of microfiltration and a cut-off level of ultrafiltration to clarify soy sauce sediment and we developed a rotating disk membrane module (RD Module) and compared performance with conventional a multi-tubular membrane module (MT Module). The optimum range to obtain soy sauce of quality was less than a pore size of O.2{mu}m for microfiltration, while ultrafiltration was not suitable for soy sauce sediment. Ultrafiltration was restricted by rejection of colors and nucleic acids and related compounds in soy sauce sediment, rather than rejection of bacteria and ethanol. An RD Module could recover soy sauce of quality and was superior to an MT Module for concentration ratio, but the permeate fluxes of the RD Module decreased under conditions of high revolution as centrifugal forces were exerted on the permeate in the disk membrane. The power consumption of the RD Module was proportional to the cube of number of revolutions and to the fifth power of the radius, so it was found that one of methods for the scale up is to increase the number of disk membranes than increase the radius. 15 refs., 8 figs., 1 tab.

Effects of amplitude modulation on perception of wind turbine noise

Energy Technology Data Exchange (ETDEWEB)

Yoon, Ki Seop; Lee, Soo Gab; Gwak, Doo Young [Dept. of Mechanical and Aerospace Engineering, Seoul National University, Seoul (Korea, Republic of); Seong, Yeol Wan [Ammunition Engineering Team, Defense Agency for Technology and Quality, Daejeon (Korea, Republic of); Lee, Seung Hoon [Aerodynamics Research Team, Korea Aerospace Research Institute, Daejeon (Korea, Republic of); Hong, Ji Young [Transportation Environmental Research Team, Green Transport and Logistics Institute, Korea Railroad Research Institute, Uiwang (Korea, Republic of)

2016-10-15

Wind turbine noise is considered to be easily detectable and highly annoying at relatively lower sound levels than other noise sources. Many previous studies attributed this characteristic to amplitude modulation. However, it is unclear whether amplitude modulation is the main cause of these properties of wind turbine noise. Therefore, the aim of the current study is to identify the relationship between amplitude modulation and these two properties of wind turbine noise. For this investigation, two experiments were conducted. In the first experiment, 12 participants determined the detection thresholds of six target sounds in the presence of background noise. In the second experiment, 12 participants matched the loudness of modified sounds without amplitude modulation to that of target sounds with amplitude modulation. The results showed that the detection threshold was lowered as the modulation depth increased; additionally, sounds with amplitude modulation had higher subjective loudness than those without amplitude modulation.

Effects of amplitude modulation on perception of wind turbine noise

International Nuclear Information System (INIS)

Yoon, Ki Seop; Lee, Soo Gab; Gwak, Doo Young; Seong, Yeol Wan; Lee, Seung Hoon; Hong, Ji Young

2016-01-01

Wind turbine noise is considered to be easily detectable and highly annoying at relatively lower sound levels than other noise sources. Many previous studies attributed this characteristic to amplitude modulation. However, it is unclear whether amplitude modulation is the main cause of these properties of wind turbine noise. Therefore, the aim of the current study is to identify the relationship between amplitude modulation and these two properties of wind turbine noise. For this investigation, two experiments were conducted. In the first experiment, 12 participants determined the detection thresholds of six target sounds in the presence of background noise. In the second experiment, 12 participants matched the loudness of modified sounds without amplitude modulation to that of target sounds with amplitude modulation. The results showed that the detection threshold was lowered as the modulation depth increased; additionally, sounds with amplitude modulation had higher subjective loudness than those without amplitude modulation

Phase-Modulated Optical Communication Systems

CERN Document Server

Ho, Keang-Po

2005-01-01

Fiber-optic communication systems have revolutionized our telecommunication infrastructures – currently, almost all telephone land-line, cellular, and internet communications must travel via some form of optical fibers. In these transmission systems, neither the phase nor frequency of the optical signal carries information – only the intensity of the signal is used. To transmit more information in a single optical carrier, the phase of the optical carrier must be explored. As a result, there is renewed interest in phase-modulated optical communications, mainly in direct-detection DPSK signals for long-haul optical communication systems. When optical amplifiers are used to maintain certain signal level among the fiber link, the system is limited by amplifier noises and fiber nonlinearities. Phase-Modulated Optical Communication Systems surveys this newly popular area, covering the following topics: The transmitter and receiver for phase-modulated coherent lightwave systems Method for performance analysis o...

Down-conversion IM-DD RF photonic link utilizing MQW MZ modulator.

Science.gov (United States)

Xu, Longtao; Jin, Shilei; Li, Yifei

2016-04-18

We present the first down-conversion intensity modulated-direct detection (IM-DD) RF photonic link that achieves frequency down-conversion using the nonlinear optical phase modulation inside a Mach-Zehnder (MZ) modulator. The nonlinear phase modulation is very sensitive and it can enable high RF-to-IF conversion efficiency. Furthermore, the link linearity is enhanced by canceling the nonlinear distortions from the nonlinear phase modulation and the MZ interferometer. Proof-of-concept measurement was performed. The down-conversion IM-DD link demonstrated 28dB improvement in distortion levels over that of a conventional IM-DD link using a LiNbO3 MZ modulator.

Loss and thermal redistributed modulation methods for three-level neutral-point-clamped wind power inverter undergoing Low Voltage Ride Through

DEFF Research Database (Denmark)

Ma, Ke; Blaabjerg, Frede

2012-01-01

The three-level neutral-point-clamped (3L-NPC) converter is a promising multilevel topology in the application of mega-watts wind power generation system. However, the growing requirements by grid codes may impose high stress and even give reliability problem to this converter topology. This paper...... modulation methods, the thermal distribution in the 3L-NPC wind power inverter undergoing LVRT becomes more equal, and the junction temperature of the most stressed devices can be also relieved. Also the control ability of DC-bus neutral point potential, which is one of the crucial considerations for the 3L...

Neuroprotective Effects of Psychotropic Drugs in Huntington’s Disease

Directory of Open Access Journals (Sweden)

Edward C. Lauterbach

2013-11-01

Full Text Available Psychotropics (antipsychotics, mood stabilizers, antidepressants, anxiolytics, etc. are commonly prescribed to treat Huntington’s disease (HD. In HD preclinical models, while no psychotropic has convincingly affected huntingtin gene, HD modifying gene, or huntingtin protein expression, psychotropic neuroprotective effects include upregulated huntingtin autophagy (lithium, histone acetylation (lithium, valproate, lamotrigine, miR-222 (lithium-plus-valproate, mitochondrial protection (haloperidol, trifluoperazine, imipramine, desipramine, nortriptyline, maprotiline, trazodone, sertraline, venlafaxine, melatonin, neurogenesis (lithium, valproate, fluoxetine, sertraline, and BDNF (lithium, valproate, sertraline and downregulated AP-1 DNA binding (lithium, p53 (lithium, huntingtin aggregation (antipsychotics, lithium, and apoptosis (trifluoperazine, loxapine, lithium, desipramine, nortriptyline, maprotiline, cyproheptadine, melatonin. In HD live mouse models, delayed disease onset (nortriptyline, melatonin, striatal preservation (haloperidol, tetrabenazine, lithium, sertraline, memory preservation (imipramine, trazodone, fluoxetine, sertraline, venlafaxine, motor improvement (tetrabenazine, lithium, valproate, imipramine, nortriptyline, trazodone, sertraline, venlafaxine, and extended survival (lithium, valproate, sertraline, melatonin have been documented. Upregulated CREB binding protein (CBP; valproate, dextromethorphan and downregulated histone deacetylase (HDAC; valproate await demonstration in HD models. Most preclinical findings await replication and their limitations are reviewed. The most promising findings involve replicated striatal neuroprotection and phenotypic disease modification in transgenic mice for tetrabenazine and for sertraline. Clinical data consist of an uncontrolled lithium case series (n = 3 suggesting non-progression and a primarily negative double-blind, placebo-controlled clinical trial of lamotrigine.

Reward modulates perception in binocular rivalry.

Science.gov (United States)

Marx, Svenja; Einhäuser, Wolfgang

2015-01-14

Our perception does not provide us with an exact imprint of the outside world, but is continuously adapted to our internal expectations, task sets, and behavioral goals. Although effects of reward-or value in general-on perception therefore seem likely, how valuation modulates perception and how such modulation relates to attention is largely unknown. We probed effects of reward on perception by using a binocular-rivalry paradigm. Distinct gratings drifting in opposite directions were presented to each observer's eyes. To objectify their subjective perceptual experience, the optokinetic nystagmus was used as measure of current perceptual dominance. In a first experiment, one of the percepts was either rewarded or attended. We found that reward and attention similarly biased perception. In a second experiment, observers performed an attentionally demanding task either on the rewarded stimulus, the other stimulus, or both. We found that-on top of an attentional effect on perception-at each level of attentional load, reward still modulated perception by increasing the dominance of the rewarded percept. Similarly, penalizing one percept increased dominance of the other at each level of attentional load. In turn, rewarding-and similarly nonpunishing-a percept yielded performance benefits that are typically associated with selective attention. In conclusion, our data show that value modulates perception in a similar way as the volitional deployment of attention, even though the relative effect of value is largely unaffected by an attention task. © 2015 ARVO.

3D Pattern Synthesis of Time-Modulated Conformal Arrays with a Multiobjective Optimization Approach

Directory of Open Access Journals (Sweden)

Wentao Li

2014-01-01

Full Text Available This paper addresses the synthesis of the three-dimensional (3D radiation patterns of the time-modulated conformal arrays. Due to the nature of periodic time modulation, harmonic radiation patterns are generated at the multiples of the modulation frequency in time-modulated arrays. Thus, the optimization goal of the time-modulated conformal array includes the optimization of the sidelobe level at the operating frequency and the sideband levels (SBLs at the harmonic frequency, and the design can be regarded as a multiobjective problem. The multiobjective particle swarm optimization (MOPSO is applied to optimize the switch-on instants and pulse durations of the time-modulated conformal array. To significantly reduce the optimization variables, the modified Bernstein polynomial is employed in the synthesis process. Furthermore, dual polarized patch antenna is designed as radiator to achieve low cross-polarization level during the beam scanning. A 12 × 13 (156-element conical conformal microstrip array is simulated to demonstrate the proposed synthesis mechanism, and good results reveal the promising ability of the proposed algorithm in solving the synthesis of the time-modulated conformal arrays problem.

Local sleep spindle modulations in relation to specific memory cues

NARCIS (Netherlands)

Cox, R.; Hofman, W.F.; de Boer, M.; Talamini, L.M.

2014-01-01

Sleep spindles have been connected to memory processes in various ways. In addition, spindles appear to be modulated at the local cortical network level. We investigated whether cueing specific memories during sleep leads to localized spindle modulations in humans. During learning of word-location

Creatures of habit (and control: a multi-level learning perspective on the modulation of congruency effects

Directory of Open Access Journals (Sweden)

Tobias eEgner

2014-11-01

Full Text Available The congruency sequence effect (CSE describes the finding that congruency effects in classic probes of selective attention (like the Stroop, Simon, and flanker tasks are smaller following an incongruent than following a congruent trial. The past two decades have generated a large literature on determinants and boundary conditions for the CSE and similar, congruency-proportion based modulations of congruency effects. A prolonged and heated theoretical discussion has been guided primarily by a historically motivated dichotomy between top-down control versus associative bottom-up explanations for these effects. In the present article, I attempt to integrate and contextualize the major empirical findings in this field by arguing that CSEs (and related effects are best understood as reflecting a composite of multiple levels of learning that differ in their level of abstraction. Specifically, learning does not only involve the trial-by-trial encoding, binding, and cued retrieval of specific stimulus-response associations, but also of more abstract trial features, including the spatial and temporal context in which a stimulus occurs, as well as internal states, like the experience of difficulty, and the attentional control settings that were employed in dealing with the stimulus. From this perspective, top-down control and bottom-up priming processes work in concert rather than in opposition. They represent different levels of abstraction in the same learning scheme and they serve a single, common goal: forming memory ensembles that will facilitate fast and appropriate responding to recurring stimuli or events in the environment.

Resveratrol, by modulating RNA processing factor levels, can influence the alternative splicing of pre-mRNAs.

Science.gov (United States)

Markus, M Andrea; Marques, Francine Z; Morris, Brian J

2011-01-01

Alternative pre-mRNA splicing defects can contribute to, or result from, various diseases, including cancer. Aberrant mRNAs, splicing factors and other RNA processing factors have therefore become targets for new therapeutic interventions. Here we report that the natural polyphenol resveratrol can modulate alternative splicing in a target-specific manner. We transfected minigenes of several alternatively spliceable primary mRNAs into HEK293 cells in the presence or absence of 1, 5, 20 and 50 µM resveratrol and measured exon levels by semi-quantitative PCR after separation by agarose gel electrophoresis. We found that 20 µg/ml and 50 µg/ml of resveratrol affected exon inclusion of SRp20 and SMN2 pre-mRNAs, but not CD44v5 or tau pre-mRNAs. By Western blotting and immunofluorescence we showed that this effect may be due to the ability of resveratrol to change the protein level but not the localization of several RNA processing factors. The processing factors that increased significantly were ASF/SF2, hnRNPA1 and HuR, but resveratrol did not change the levels of RBM4, PTBP1 and U2AF35. By means of siRNA-mediated knockdown we depleted cells of SIRT1, regarded as a major target of resveratrol, and showed that the effect on splicing was not dependent on SIRT1. Our results suggest that resveratrol might be an attractive small molecule to treat diseases in which aberrant splicing has been implicated, and justify more extensive research on the effects of resveratrol on the splicing machinery.

Power Inverter Topologies for Photovoltaic Modules - A Review

DEFF Research Database (Denmark)

Kjær, Søren Bækhøj; Pedersen, John Kim; Blaabjerg, Frede

2002-01-01

This review-paper focuses on the latest development of inverters for photovoltaic AC-Modules. The power range for these inverters is usually within 90 Watt to 500 Watt, which covers the most commercial photovoltaic-modules. Self-commutated inverters have replaced the grid-commutated ones. The same...... is true for the bulky low-frequency transformers versus the high-frequency transformers, which are used to adapt the voltage level. The AC-Module provides a modular design and a flexible behaviour in various grid conditions. It hereby opens the market for photovoltaic-power for everyone at a low cost due...

Qualification Procedures of the CMS Pixel Barrel Modules

CERN Document Server

Starodumov, A; Horisberger, R.; Kastli, H.Chr.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Trueb, P.

2006-01-01

The CMS pixel barrel system will consist of three layers built of about 800 modules. One module contains 66560 readout channels and the full pixel barrel system about 48 million channels. It is mandatory to test each channel for functionality, noise level, trimming mechanism, and bump bonding quality. Different methods to determine the bump bonding yield with electrical measurements have been developed. Measurements of several operational parameters are also included in the qualification procedure. Among them are pixel noise, gains and pedestals. Test and qualification procedures of the pixel barrel modules are described and some results are presented.

Assessment of a new undergraduate module in musculoskeletal medicine.

Science.gov (United States)

Queally, Joseph M; Cummins, Fionnan; Brennan, Stephen A; Shelly, Martin J; O'Byrne, John M

2011-02-02

Despite the high prevalence of musculoskeletal disorders seen by primary care physicians, numerous studies have demonstrated deficiencies in the adequacy of musculoskeletal education at multiple stages of medical education. The aim of this study was to assess a newly developed module in musculoskeletal medicine for use at European undergraduate level (i.e., the medical-school level). A two-week module in musculoskeletal medicine was designed to cover common musculoskeletal disorders that are typically seen in primary care. The module incorporated an integrated approach, including core lectures, bedside clinical examination, and demonstration of basic practical procedures. A previously validated examination in musculoskeletal medicine was used to assess the cognitive knowledge of ninety-two students on completion of the module. A historical control group (seventy-two students) from a prior course was used for comparison. The new module group (2009) performed significantly better than the historical (2006) control group in terms of score (62.3% versus 54.3%, respectively; p pass rate (38.4% versus 12.5%, respectively; p = 0.0002). In a subgroup analysis of the new module group, students who enrolled in the graduate entry program (an accelerated four-year curriculum consisting of students who have already completed an undergraduate university degree) were more likely to perform better in terms of average score (72.2% versus 57%, respectively; p pass rates (70.9% versus 21.4%, respectively; p paper represents an educational advance at undergraduate (i.e., medical-school) level as demonstrated by the improvement in scores in a validated examination. As pressure on medical curricula grows to accommodate advancing medical knowledge, it is important to continue to improve, assess, and consolidate the position of musculoskeletal medicine in contemporary medical education.

Qualification testing of flat-plate photovoltaic modules

Science.gov (United States)

Hoffman, A. R.; Griffith, J. S.; Ross, R. G., Jr.

1982-01-01

The placement of photovoltaic modules in various applications, in climates and locations throughout the world, results in different degrees and combinations of environmental and electrical stress. Early detection of module reliability deficiencies via laboratory testing is necessary for achieving long, satisfactory field service. This overview paper describes qualification testing techniques being used in the US Department of Energy's flat-plate terrestrial photovoltaic development program in terms of their significance, rationale for specified levels and durations, and test results.

Peltier coefficient measurement in a thermoelectric module

International Nuclear Information System (INIS)

Garrido, Javier; Casanovas, Alejandro; Chimeno, José María

2013-01-01

A new method for measuring the Peltier coefficient in a thermocouple X/Y based on the energy balance at the junction has been proposed recently. This technique needs only the hot and cold temperatures of a thermoelectric module when an electric current flows through it as the operational variables. The temperature evolutions of the two module sides provide an evident and accurate idea of the Peltier effect. From these temperatures, the heat transfer between the module and the ambient is also evaluated. The thermoelectric phenomena are described in the framework of an observable theory. Based on this procedure, an experiment is presented for a university teaching laboratory at the undergraduate level. (paper)

Data collection modules for the PHENIX experiment

International Nuclear Information System (INIS)

Chi, C.Y.; Cole, B.; Nagle, J.L.; Sippach, W.; Zajc, W.A.

1998-01-01

The data acquisition (DAQ) system for the PHENIX experiment is designed as a pipeline system with simultaneous triggering and readout. The maximum average level-1 (LVL1) trigger rate is 25 KHz. The DAQ system consists of Front-End Modules (FEM's), a level-1 (LVL1) trigger, data collection modules (DCM's) timing systems, slow controllers and an event builder (EVB). The data collection modules have the responsibility of collecting uncompressed LVL1 trigger event fragments from the FEM's. The DCM's provide buffering for up to five LVL1 events. The DCM's also perform zero suppression, error checking, data reformatting and outputting data to the event builder. In addition to the FEM data, the DCM's also receive primitives from LVL1 trigger system. These primitives are used for alignment checking on the FEM data packet. Additional trigger primitives can also be generated together with the FEM data. The DCM is hosted in a VME crate. VME is used as a means for maintenance and slow control. Data collection within the crate is done through a private data-way

Canons, competencies and critique: delivering an undergraduate entrepreneurial marketing module

OpenAIRE

Ardley, Barry; Hardwick, Jialin

2017-01-01

In the context of the debate about the status of marketing degrees, graduate knowledge and competencies, this paper reflects on a set of pedagogic issues associated with the delivery of a final level entrepreneurial marketing module. Drawing on key literature, the module takes a set of entrepreneurial marketing canons as the basis of learning. Primary research was conducted into student perceptions of the module based on an interpretative methodology, using an open ended questionnaire. Studen...

Contextual modulation and stimulus selectivity in extrastriate cortex.

Science.gov (United States)

Krause, Matthew R; Pack, Christopher C

2014-11-01

Contextual modulation is observed throughout the visual system, using techniques ranging from single-neuron recordings to behavioral experiments. Its role in generating feature selectivity within the retina and primary visual cortex has been extensively described in the literature. Here, we describe how similar computations can also elaborate feature selectivity in the extrastriate areas of both the dorsal and ventral streams of the primate visual system. We discuss recent work that makes use of normalization models to test specific roles for contextual modulation in visual cortex function. We suggest that contextual modulation renders neuronal populations more selective for naturalistic stimuli. Specifically, we discuss contextual modulation's role in processing optic flow in areas MT and MST and for representing naturally occurring curvature and contours in areas V4 and IT. We also describe how the circuitry that supports contextual modulation is robust to variations in overall input levels. Finally, we describe how this theory relates to other hypothesized roles for contextual modulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Security Injections 2.0: Increasing Engagement and Faculty Adoption Using Enhanced Secure Coding Modules for Lower-Level Programming Courses

OpenAIRE

Raina , Sagar; Taylor , Blair; Kaza , Siddharth

2015-01-01

Part 2: Software Security Education; International audience; Learning interventions based on modules are common in computer science education. Traditional learning modules that present a large amount of content in a linear format can lead to students skimming and skipping content resulting in lower student engagement and effectiveness. In this paper, we present theoretical support for increasing engagement and effectiveness of learning modules, describe a system that implements these principl...

State-dependent, bidirectional modulation of neural network activity by endocannabinoids.

Science.gov (United States)

Piet, Richard; Garenne, André; Farrugia, Fanny; Le Masson, Gwendal; Marsicano, Giovanni; Chavis, Pascale; Manzoni, Olivier J

2011-11-16

The endocannabinoid (eCB) system and the cannabinoid CB1 receptor (CB1R) play key roles in the modulation of brain functions. Although actions of eCBs and CB1Rs are well described at the synaptic level, little is known of their modulation of neural activity at the network level. Using microelectrode arrays, we have examined the role of CB1R activation in the modulation of the electrical activity of rat and mice cortical neural networks in vitro. We find that exogenous activation of CB1Rs expressed on glutamatergic neurons decreases the spontaneous activity of cortical neural networks. Moreover, we observe that the net effect of the CB1R antagonist AM251 inversely correlates with the initial level of activity in the network: blocking CB1Rs increases network activity when basal network activity is low, whereas it depresses spontaneous activity when its initial level is high. Our results reveal a complex role of CB1Rs in shaping spontaneous network activity, and suggest that the outcome of endogenous neuromodulation on network function might be state dependent.

Modulation of genetic associations with serum urate levels by body-mass-index in humans.

Directory of Open Access Journals (Sweden)

Jennifer E Huffman

Full Text Available We tested for interactions between body mass index (BMI and common genetic variants affecting serum urate levels, genome-wide, in up to 42569 participants. Both stratified genome-wide association (GWAS analyses, in lean, overweight and obese individuals, and regression-type analyses in a non BMI-stratified overall sample were performed. The former did not uncover any novel locus with a major main effect, but supported modulation of effects for some known and potentially new urate loci. The latter highlighted a SNP at RBFOX3 reaching genome-wide significant level (effect size 0.014, 95% CI 0.008-0.02, Pinter= 2.6 x 10-8. Two top loci in interaction term analyses, RBFOX3 and ERO1LB-EDARADD, also displayed suggestive differences in main effect size between the lean and obese strata. All top ranking loci for urate effect differences between BMI categories were novel and most had small magnitude but opposite direction effects between strata. They include the locus RBMS1-TANK (men, Pdifflean-overweight= 4.7 x 10-8, a region that has been associated with several obesity related traits, and TSPYL5 (men, Pdifflean-overweight= 9.1 x 10-8, regulating adipocytes-produced estradiol. The top-ranking known urate loci was ABCG2, the strongest known gout risk locus, with an effect halved in obese compared to lean men (Pdifflean-obese= 2 x 10-4. Finally, pathway analysis suggested a role for N-glycan biosynthesis as a prominent urate-associated pathway in the lean stratum. These results illustrate a potentially powerful way to monitor changes occurring in obesogenic environment.

Motor modules in robot-aided walking

Directory of Open Access Journals (Sweden)

Gizzi Leonardo

2012-10-01

Full Text Available Abstract Background It is hypothesized that locomotion is achieved by means of rhythm generating networks (central pattern generators and muscle activation generating networks. This modular organization can be partly identified from the analysis of the muscular activity by means of factorization algorithms. The activity of rhythm generating networks is described by activation signals whilst the muscle intervention generating network is represented by motor modules (muscle synergies. In this study, we extend the analysis of modular organization of walking to the case of robot-aided locomotion, at varying speed and body weight support level. Methods Non Negative Matrix Factorization was applied on surface electromyographic signals of 8 lower limb muscles of healthy subjects walking in gait robotic trainer at different walking velocities (1 to 3km/h and levels of body weight support (0 to 30%. Results The muscular activity of volunteers could be described by low dimensionality (4 modules, as for overground walking. Moreover, the activation signals during robot-aided walking were bursts of activation timed at specific phases of the gait cycle, underlying an impulsive controller, as also observed in overground walking. This modular organization was consistent across the investigated speeds, body weight support level, and subjects. Conclusions These results indicate that walking in a Lokomat robotic trainer is achieved by similar motor modules and activation signals as overground walking and thus supports the use of robotic training for re-establishing natural walking patterns.

Comparative Study on Atmospheric Dispersion Module of Level 3 PSA

Energy Technology Data Exchange (ETDEWEB)

Kwon, Dahye; Jang, Misuk; Kang, Hyun Sik; Kim, Seoung Rae [NESS, Daejeon (Korea, Republic of)

2016-10-15

Some regulation documents such as Regulatory Guides and NUREG publications from the U.S. Nuclear Regulatory Commission (NRC) have influences on domestic radiation environmental analyses. As renewal versions of NUREG-0800 and NUREG-1555 have issued lately, the assessment for Severe Accident (SA) with Probabilistic Safety Assessment (PSA) should be added to Safety Analysis Report (SAR) and Radiation Environmental Report (RER). Because these reports are the required documents for obtaining the construction permit and operating license, it is important to understand the PSA methodology and it needs to improve the site-specific input data of L3PSA codes for SA. First, our review focuses on the atmospheric dispersion and deposition related input data of L3PSA code in this paper. Then we will continue to review the improvements of other input data. Two atmospheric dispersion models, which are PAVAN developed for design basis accident and ATMOS of MACCS2 code developed for SA, were reviewed in this paper. L3PSA deals with the effects of severe accidents and basically includes the evaluation of both short- and long-term effects. Therefore, both the deposition effects and nuclide information(type, amount, and chemical characteristics of released radionuclide) would be considered as the input parameters of atmospheric dispersion model for L3PSA. Additionally, the meteorological data would be sampled randomly to meet the purpose of probabilistic method. However, the sampling method would be selected according to analysis purpose. After review, ATMOS module and its input data are suitably developed for the atmospheric dispersion analysis of L3PSA. However, ATMOS module was developed using the site-specific terrain and environment characteristics. For the domestic application, it needs to study the input data reflecting the Korean terrain and environment characteristics. It would be also continuously improved in response to the time- and site-specific changes of weather

Photovoltaic Cells and Modules towards Terawatt Era

Institute of Scientific and Technical Information of China (English)

Vitezslav Benda

2017-01-01

Progresses in photovoltaic technologies over the past years are evident from the lower costs,the rising efficiency,to the great improvements in system reliability and yield.Cumulative installed power yearly growths were on an average more than 40％ in the period from 2007 to 2016 and in 2016,the global cumulative photovoltaic power installed has reached 320 GWp.The level 0.5 TWp could be reached before 2020.The production processes in the solar industry still have great potential for optimization both wafer based and thin film technologies.Trends following from the present technology levels are discussed,also taking into account other parts of photovoltaic systems that influence the cost of electrical energy produced.Present developments in the three generations of photovoltaic modules are discussed along with the criteria for the selection of appropriate photovoltaic module manufacturing technologies.The wafer based crystalline silicon (c-silicon) technologies have the role of workhorse of present photovoltaic power generation,representing more than 90％ of total module production.Further technology improvements have to be implemented without significantly increasing costs per unit,despite the necessarily more complex manufacturing processes involved.The tandem of c-silicon and thin film cells is very promising.Durability may be a limiting factor of this technology due to the dependence of the produced electricity cost on the module service time.

Pengembangan Modul Bimbingan dan Konseling untuk Pencegahan Bullying di Sekolah

Directory of Open Access Journals (Sweden)

Hengki Yandri

2013-03-01

Full Text Available This research aims to formulate guidance and counseling module to prevent bullying at school and to describe the level of applicability used by counselor. The method used was ADDIE model development. The subjects of the research consisted of guidance and counseling expert and the intended target of the module (counselor, chosen through purposive sampling. The instruments used were questionnaire and focus group discussion (FGD. The data were analyzed descriptively. The results showed that prototype modules developed to prevent bullying at school is applicable used by the counselor and those modules can be utilized by counselor to prevent bullying at school.

How bees distinguish patterns by green and blue modulation.

Science.gov (United States)

Horridge, Adrian

2015-01-01

In the 1920s, Mathilde Hertz found that trained bees discriminated between shapes or patterns of similar size by something related to total length of contrasting contours. This input is now interpreted as modulation in green and blue receptor channels as flying bees scan in the horizontal plane. Modulation is defined as total contrast irrespective of sign multiplied by length of edge displaying that contrast, projected to vertical, therefore, combining structure and contrast in a single input. Contrast is outside the eye; modulation is a phasic response in receptor pathways inside. In recent experiments, bees trained to distinguish color detected, located, and measured three independent inputs and the angles between them. They are the tonic response of the blue receptor pathway and modulation of small-field green or (less preferred) blue receptor pathways. Green and blue channels interacted intimately at a peripheral level. This study explores in more detail how various patterns are discriminated by these cues. The direction of contrast at a boundary was not detected. Instead, bees located and measured total modulation generated by horizontal scanning of contrasts, irrespective of pattern. They also located the positions of isolated vertical edges relative to other landmarks and distinguished the angular widths between vertical edges by green or blue modulation alone. The preferred inputs were the strongest green modulation signal and angular width between outside edges, irrespective of color. In the absence of green modulation, the remaining cue was a measure and location of blue modulation at edges. In the presence of green modulation, blue modulation was inhibited. Black/white patterns were distinguished by the same inputs in blue and green receptor channels. Left-right polarity and mirror images could be discriminated by retinotopic green modulation alone. Colors in areas bounded by strong green contrast were distinguished as more or less blue than the

Fast Convolution Module (Fast Convolution Module)

National Research Council Canada - National Science Library

Bierens, L

1997-01-01

This report describes the design and realisation of a real-time range azimuth compression module, the so-called 'Fast Convolution Module', based on the fast convolution algorithm developed at TNO-FEL...

Deficient Rab11 activity underlies glucose hypometabolism in primary neurons of Huntington’s disease mice

International Nuclear Information System (INIS)

Li, Xueyi; Valencia, Antonio; McClory, Hollis; Sapp, Ellen; Kegel, Kimberly B.; DiFiglia, Marian

2012-01-01

Highlights: ► Primary Huntington’s disease neurons are impaired in taking up glucose. ► Rab11 modulates glucose uptake in neurons. ► Increasing Rab11 activity attenuates the glucose uptake defect in disease neurons. ► We provide a novel mechanism for glucose hypometabolism in Huntington’s disease. -- Abstract: Huntington’s disease (HD) is a progressive neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene. Positron emission tomography studies have revealed a decline in glucose metabolism in the brain of patients with HD by a mechanism that has not been established. We examined glucose utilization in embryonic primary cortical neurons of wild-type (WT) and HD knock-in mice, which have 140 CAG repeats inserted in the endogenous mouse huntingtin gene (HD 140Q/140Q ). Primary HD 140Q/140Q cortical neurons took up significantly less glucose than did WT neurons. Expression of permanently inactive and permanently active forms of Rab11 correspondingly altered glucose uptake in WT neurons, suggesting that normal activity of Rab11 is needed for neuronal uptake of glucose. It is known that Rab11 activity is diminished in HD 140Q/140Q neurons. Expression of dominant active Rab11 to enhance the activity of Rab11 normalized glucose uptake in HD 140Q/140Q neurons. These results suggest that deficient activity of Rab11 is a novel mechanism for glucose hypometabolism in HD.

MO-AB-BRA-01: A Global Level Set Based Formulation for Volumetric Modulated Arc Therapy

Energy Technology Data Exchange (ETDEWEB)

Nguyen, D; Lyu, Q; Ruan, D; O’Connor, D; Low, D; Sheng, K [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA (United States)

2016-06-15

Purpose: The current clinical Volumetric Modulated Arc Therapy (VMAT) optimization is formulated as a non-convex problem and various greedy heuristics have been employed for an empirical solution, jeopardizing plan consistency and quality. We introduce a novel global direct aperture optimization method for VMAT to overcome these limitations. Methods: The global VMAT (gVMAT) planning was formulated as an optimization problem with an L2-norm fidelity term and an anisotropic total variation term. A level set function was used to describe the aperture shapes and adjacent aperture shapes were penalized to control MLC motion range. An alternating optimization strategy was implemented to solve the fluence intensity and aperture shapes simultaneously. Single arc gVMAT plans, utilizing 180 beams with 2° angular resolution, were generated for a glioblastoma multiforme (GBM), lung (LNG), and 2 head and neck cases—one with 3 PTVs (H&N3PTV) and one with 4 PTVs (H&N4PTV). The plans were compared against the clinical VMAT (cVMAT) plans utilizing two overlapping coplanar arcs. Results: The optimization of the gVMAT plans had converged within 600 iterations. gVMAT reduced the average max and mean OAR dose by 6.59% and 7.45% of the prescription dose. Reductions in max dose and mean dose were as high as 14.5 Gy in the LNG case and 15.3 Gy in the H&N3PTV case. PTV coverages (D95, D98, D99) were within 0.25% of the prescription dose. By globally considering all beams, the gVMAT optimizer allowed some beams to deliver higher intensities, yielding a dose distribution that resembles a static beam IMRT plan with beam orientation optimization. Conclusions: The novel VMAT approach allows for the search of an optimal plan in the global solution space and generates deliverable apertures directly. The single arc VMAT approach fully utilizes the digital linacs’ capability in dose rate and gantry rotation speed modulation. Varian Medical Systems, NIH grant R01CA188300, NIH grant R43CA183390.

Unifying and generating of space vector modulation sequences for multilevel converter

DEFF Research Database (Denmark)

Ma, Ke; Blaabjerg, Frede

2014-01-01

Space Vector Modulation (SVM) is a powerful method which enables some freedom to generate the modulation sequences and modify the performances of converter. However, in the multi-level converter structures, the number of switching state redundancies significantly increases, and the determination...

Multilevel photonic modules for millimeter-wave phased-array antennas

Science.gov (United States)

Paolella, Arthur C.; Bauerle, Athena; Joshi, Abhay M.; Wright, James G.; Coryell, Louis A.

2000-09-01

Millimeter wave phased array systems have antenna element sizes and spacings similar to MMIC chip dimensions by virtue of the operating wavelength. Designing modules in traditional planar packaing techniques are therefore difficult to implement. An advantageous way to maintain a small module footprint compatible with Ka-Band and high frequency systems is to take advantage of two leading edge technologies, opto- electronic integrated circuits (OEICs) and multilevel packaging technology. Under a Phase II SBIR these technologies are combined to form photonic modules for optically controlled millimeter wave phased array antennas. The proposed module, consisting of an OEIC integrated with a planar antenna array will operate on the 40GHz region. The OEIC consists of an InP based dual-depletion PIN photodetector and distributed amplifier. The multi-level module will be fabricated using an enhanced circuit processing thick film process. Since the modules are batch fabricated using an enhanced circuit processing thick film process. Since the modules are batch fabricated, using standard commercial processes, it has the potential to be low cost while maintaining high performance, impacting both military and commercial communications systems.

Cross-Modulation Interference with Lateralization of Mixed-Modulated Waveforms

Science.gov (United States)

Hsieh, I-Hui; Petrosyan, Agavni; Goncalves, Oscar F.; Hickok, Gregory; Saberi, Kourosh

2010-01-01

Purpose: This study investigated the ability to use spatial information in mixed-modulated (MM) sounds containing concurrent frequency-modulated (FM) and amplitude-modulated (AM) sounds by exploring patterns of interference when different modulation types originated from different loci as may occur in a multisource acoustic field. Method:…

Superstability for Generalized Module Left Derivations and Generalized Module Derivations on a Banach Module (I

Directory of Open Access Journals (Sweden)

Huai-Xin Cao

2009-01-01

Full Text Available We discuss the superstability of generalized module left derivations and generalized module derivations on a Banach module. Let 𝒜 be a Banach algebra and X a Banach 𝒜-module, f:X→X and g:𝒜→𝒜. The mappings Δf,g1, Δf,g2, Δf,g3, and Δf,g4 are defined and it is proved that if ∥Δf,g1(x,y,z,w∥ (resp., ∥Δf,g3(x,y,z,w,α,β∥ is dominated by φ(x,y,z,w, then f is a generalized (resp., linear module-𝒜 left derivation and g is a (resp., linear module-X left derivation. It is also shown that if ∥Δf,g2(x,y,z,w∥ (resp., ∥Δf,g4(x,y,z,w,α,β∥ is dominated by φ(x,y,z,w, then f is a generalized (resp., linear module-𝒜 derivation and g is a (resp., linear module-X derivation.

WRAP module 1 treatment plan

International Nuclear Information System (INIS)

Mayancsik, B.A.

1995-05-01

This document provides the methodology to treat waste in the Waste Receiving and Processing Module 1 facility to meet the Resource Conservation and Recovery Act (RCRA) land disposal restrictions or the Waste Isolation and Pilot Plant waste acceptance criteria. This includes Low-Level Mixed Waste, Transuranic Waste, and Transuranic Mixed Waste

A mixed signal multi-chip module with high speed serial output links for the ATLAS Level-1 trigger

CERN Document Server

Pfeiffer, U

2000-01-01

We have built and tested a mixed signal multi-chip module (MCM) to be used in the Level-1 Pre-Processor system for the Calorimeter Trigger of the ATLAS experiment at CERN. The MCM performs high speed digital signal processing on four analogue input signals. Results are transmitted serially at a serial data rate of 800 MBd. Nine chips of different technologies are mounted on a four layer Cu substrate. ADC converters and serialiser chips are the major consumers of electrical power on the MCM, which amounts to 9 W for all dies. Special cut-out areas are used to dissipate heat directly to the copper substrate. In this paper we report on design criteria, chosen MCM technology for substrate and die mounting, experiences with the MCM operation and measurement results. (4 refs).

Plasma Triglyceride Levels May Be Modulated by Gene Expression of IQCJ, NXPH1, PHF17 and MYB in Humans

Directory of Open Access Journals (Sweden)

Bastien Vallée Marcotte

2017-01-01

Full Text Available A genome-wide association study (GWAS by our group identified loci associated with the plasma triglyceride (TG response to ω-3 fatty acid (FA supplementation in IQCJ, NXPH1, PHF17 and MYB. Our aim is to investigate potential mechanisms underlying the associations between single nucleotide polymorphisms (SNPs in the four genes and TG levels following ω-3 FA supplementation. 208 subjects received 3 g/day of ω-3 FA (1.9–2.2 g of EPA and 1.1 g of docosahexaenoic acid (DHA for six weeks. Plasma TG were measured before and after the intervention. 67 SNPs were selected to increase the density of markers near GWAS hits. Genome-wide expression and methylation analyses were conducted on respectively 30 and 35 participants’ blood sample together with in silico analyses. Two SNPs of IQCJ showed different affinities to splice sites depending on alleles. Expression levels were influenced by genotype for one SNP in NXPH1 and one in MYB. Associations between 12 tagged SNPs of IQCJ, 26 of NXPH1, seven of PHF17 and four of MYB and gene-specific CpG site methylation levels were found. The response of plasma TG to ω-3 FA supplementation may be modulated by the effect of DNA methylation on expression levels of genes revealed by GWAS.

Modulating mind-wandering in dysphoria

Directory of Open Access Journals (Sweden)

Fionnuala Catherine Murphy

2013-11-01

Full Text Available Depression is associated with significant difficulty staying ‘in the moment’ as the mind tends to wander away from current activity to focus instead on personal concerns. Mind-wandering (MW may in some instances be a precursor for depressive rumination, a thinking style believed to confer vulnerability to the likelihood and extent of depression. Though the majority of evidence examining MW and mood has been correlational, evidence indicates that MW may be not only a consequence but also a cause of low mood. Identifying a paradigm that could modulate MW, particularly in depressed individuals, would allow future studies to test whether elevated rates of MW causally drive cognitive-affective features of depression, such as rumination and anhedonia. This study therefore explored the feasibility of using an existing task manipulation to modulate behavioural and self-report indices of MW in participants with varying levels of self-reported dysphoria. Participants completed two go/no-go tasks – the SART and a high target probability task – and measures of state and trait MW. The two tasks were identical in all respects apart from the lower probability of no-go targets on the SART, a feature considered to encourage mindless, or inattentive, responding. Across participants, errors of commission (a behavioural indicator of MW were elevated on the SART relative to the high probability task, a pattern than was particularly pronounced in dysphoric participants. Dysphoric individuals furthermore reported elevated levels of MW, though the modulation of these subjective reports by task was present to a similar rather than greater extent in the dysphoric individuals. These findings provide encouraging preliminary support for the use of this paradigm as one that modulates MW in depressed individuals. The implications of these results and directions for future research are discussed.

Histone deacetylase inhibition decreases cholesterol levels in neuronal cells by modulating key genes in cholesterol synthesis, uptake and efflux.

Directory of Open Access Journals (Sweden)

Maria João Nunes

Full Text Available Cholesterol is an essential component of the central nervous system and increasing evidence suggests an association between brain cholesterol metabolism dysfunction and the onset of neurodegenerative disorders. Interestingly, histone deacetylase inhibitors (HDACi such as trichostatin A (TSA are emerging as promising therapeutic approaches in neurodegenerative diseases, but their effect on brain cholesterol metabolism is poorly understood. We have previously demonstrated that HDACi up-regulate CYP46A1 gene transcription, a key enzyme in neuronal cholesterol homeostasis. In this study, TSA was shown to modulate the transcription of other genes involved in cholesterol metabolism in human neuroblastoma cells, namely by up-regulating genes that control cholesterol efflux and down-regulating genes involved in cholesterol synthesis and uptake, thus leading to an overall decrease in total cholesterol content. Furthermore, co-treatment with the amphipathic drug U18666A that can mimic the intracellular cholesterol accumulation observed in cells of Niemman-Pick type C patients, revealed that TSA can ameliorate the phenotype induced by pathological cholesterol accumulation, by restoring the expression of key genes involved in cholesterol synthesis, uptake and efflux and promoting lysosomal cholesterol redistribution. These results clarify the role of TSA in the modulation of neuronal cholesterol metabolism at the transcriptional level, and emphasize the idea of HDAC inhibition as a promising therapeutic tool in neurodegenerative disorders with impaired cholesterol metabolism.

Modulating Neurotrophin Receptor Signaling as a Therapeutic Strategy for Huntington’s Disease

Science.gov (United States)

Simmons, Danielle A.

2017-01-01

Huntington’s disease (HD) is an autosomal dominant neurodegenerative disorder caused by CAG repeat expansions in the IT15 gene which encodes the huntingtin (HTT) protein. Currently, no treatments capable of preventing or slowing disease progression exist. Disease modifying therapeutics for HD would be expected to target a comprehensive set of degenerative processes given the diverse mechanisms contributing to HD pathogenesis including neuroinflammation, excitotoxicity, and transcription dysregulation. A major contributor to HD-related degeneration is mutant HTT-induced loss of neurotrophic support. Thus, neurotrophin (NT) receptors have emerged as therapeutic targets in HD. The considerable overlap between NT signaling networks and those dysregulated by mutant HTT provides strong theoretical support for this approach. This review will focus on the contributions of disrupted NT signaling in HD-related neurodegeneration and how targeting NT receptors to augment pro-survival signaling and/or to inhibit degenerative signaling may combat HD pathologies. Therapeutic strategies involving NT delivery, peptidomimetics, and the targeting of specific NT receptors (e.g., Trks or p75NTR), particularly with small molecule ligands, are discussed. PMID:29254102

Development of Active External Network Topology Module for Floodlight SDN Controller

Directory of Open Access Journals (Sweden)

A. A. Noskov

2015-01-01

Full Text Available Traditional network architecture is inflexible and complicated. This observation has led to a paradigm shift towards software-defined networking (SDN, where network management level is separated from data forwarding level. This change was made possible by control plane transfer from the switching equipment to software modules that run on a dedicated server, called the controller (or network operating system, or network applications, that work with this controller. Methods of representation, storage and communication interfaces with network topology elements are the most important aspects of network operating systems available to SDN user because performance of some key controller modules is heavily dependent on internal representation of the network topology. Notably, firewall and routing modules are examples of such modules. This article describes the methods used for presentation and storage of network topologies, as well as interface to the corresponding Floodlight modules. An alternative algorithm has been suggested and developed for message exchange conveying network topology alterations between the controller and network applications. Proposed algorithm makes implementation of module alerting based on subscription to the relevant events. API for interaction between controller and network applications has been developed. This algorithm and API formed the base for Topology Tracker module capable to inform network applications about the changes that had occurred in the network topology and also stores compact representation of the network to speed up the interaction process.

DNDO Report: Predicting Solar Modulation Potentials for Modeling Cosmic Background Radiation

Energy Technology Data Exchange (ETDEWEB)

Behne, Patrick Alan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-08-08

The modeling of the detectability of special nuclear material (SNM) at ports and border crossings requires accurate knowledge of the background radiation at those locations. Background radiation originates from two main sources, cosmic and terrestrial. Cosmic background is produced by high-energy galactic cosmic rays (GCR) entering the atmosphere and inducing a cascade of particles that eventually impact the earth’s surface. The solar modulation potential represents one of the primary inputs to modeling cosmic background radiation. Usosokin et al. formally define solar modulation potential as “the mean energy loss [per unit charge] of a cosmic ray particle inside the heliosphere…” Modulation potential, a function of elevation, location, and time, shares an inverse relationship with cosmic background radiation. As a result, radiation detector thresholds require adjustment to account for differing background levels, caused partly by differing solar modulations. Failure to do so can result in higher rates of false positives and failed detection of SNM for low and high levels of solar modulation potential, respectively. This study focuses on solar modulation’s time dependence, and seeks the best method to predict modulation for future dates using Python. To address the task of predicting future solar modulation, we utilize both non-linear least squares sinusoidal curve fitting and cubic spline interpolation. This material will be published in transactions of the ANS winter meeting of November, 2016.

Decoding task-based attentional modulation during face categorization.

Science.gov (United States)

Chiu, Yu-Chin; Esterman, Michael; Han, Yuefeng; Rosen, Heather; Yantis, Steven

2011-05-01

Attention is a neurocognitive mechanism that selects task-relevant sensory or mnemonic information to achieve current behavioral goals. Attentional modulation of cortical activity has been observed when attention is directed to specific locations, features, or objects. However, little is known about how high-level categorization task set modulates perceptual representations. In the current study, observers categorized faces by gender (male vs. female) or race (Asian vs. White). Each face was perceptually ambiguous in both dimensions, such that categorization of one dimension demanded selective attention to task-relevant information within the face. We used multivoxel pattern classification to show that task-specific modulations evoke reliably distinct spatial patterns of activity within three face-selective cortical regions (right fusiform face area and bilateral occipital face areas). This result suggests that patterns of activity in these regions reflect not only stimulus-specific (i.e., faces vs. houses) responses but also task-specific (i.e., race vs. gender) attentional modulation. Furthermore, exploratory whole-brain multivoxel pattern classification (using a searchlight procedure) revealed a network of dorsal fronto-parietal regions (left middle frontal gyrus and left inferior and superior parietal lobule) that also exhibit distinct patterns for the two task sets, suggesting that these regions may represent abstract goals during high-level categorization tasks.

A binaural advantage in the subjective modulation transfer function with simple impulse responses

DEFF Research Database (Denmark)

Thompson, Eric Robert; Dau, Torsten

2008-01-01

into account that humans listen with two ears. There can be large interaural phase differences in the modulation transfer functions, which can create detectable interaural level difference fluctuations. Measurements were made to determine whether these interaural modulation phase differences can be used......The speech transmission index (STI) has been a popular method for predicting speech intelligibility in rooms. It is based on the magnitude of the modulation transfer function, which can be derived from the impulse response of the room and the background noise levels. However, it does not take...

Resveratrol, by modulating RNA processing factor levels, can influence the alternative splicing of pre-mRNAs.

Directory of Open Access Journals (Sweden)

M Andrea Markus

Full Text Available Alternative pre-mRNA splicing defects can contribute to, or result from, various diseases, including cancer. Aberrant mRNAs, splicing factors and other RNA processing factors have therefore become targets for new therapeutic interventions. Here we report that the natural polyphenol resveratrol can modulate alternative splicing in a target-specific manner. We transfected minigenes of several alternatively spliceable primary mRNAs into HEK293 cells in the presence or absence of 1, 5, 20 and 50 µM resveratrol and measured exon levels by semi-quantitative PCR after separation by agarose gel electrophoresis. We found that 20 µg/ml and 50 µg/ml of resveratrol affected exon inclusion of SRp20 and SMN2 pre-mRNAs, but not CD44v5 or tau pre-mRNAs. By Western blotting and immunofluorescence we showed that this effect may be due to the ability of resveratrol to change the protein level but not the localization of several RNA processing factors. The processing factors that increased significantly were ASF/SF2, hnRNPA1 and HuR, but resveratrol did not change the levels of RBM4, PTBP1 and U2AF35. By means of siRNA-mediated knockdown we depleted cells of SIRT1, regarded as a major target of resveratrol, and showed that the effect on splicing was not dependent on SIRT1. Our results suggest that resveratrol might be an attractive small molecule to treat diseases in which aberrant splicing has been implicated, and justify more extensive research on the effects of resveratrol on the splicing machinery.

LRP5 and plasma cholesterol levels modulate the canonical Wnt pathway in peripheral blood leukocytes.

Science.gov (United States)

Borrell-Pages, Maria; Carolina Romero, July; Badimon, Lina

2015-08-01

Inflammation is triggered after invasion or injury to restore homeostasis. Although the activation of Wnt/β-catenin signaling is one of the first molecular responses to cellular damage, its role in inflammation is still unclear. It was our hypothesis that the low-density lipoprotein (LDL) receptor-related protein 5 (LRP5) and the canonical Wnt signaling pathway are modulators of inflammatory mechanisms. Wild-type (WT) and LRP5(-/-) mice were fed a hypercholesterolemic (HC) diet to trigger dislipidemia and chronic inflammation. Diets were supplemented with plant sterol esters (PSEs) to induce LDL cholesterol lowering and the reduction of inflammation. HC WT mice showed increased serum cholesterol levels that correlated with increased Lrp5 and Wnt/β-catenin gene expression while in the HC LRP5(-/-) mice Wnt/β-catenin pathway was shut down. Functionally, HC induced pro-inflammatory gene expression in LRP5(-/-) mice, suggesting an inhibitory role of the Wnt pathway in inflammation. Dietary PSE administration downregulated serum cholesterol levels in WT and LRP5(-/-) mice. Furthermore, in WT mice PSE increased anti-inflammatory genes expression and inhibited Wnt/β-catenin activation. Hepatic gene expression of Vldlr, Lrp2 and Lrp6 was increased after HC feeding in WT mice but not in LRP5(-/-) mice, suggesting a role for these receptors in the clearance of plasmatic lipoproteins. Finally, an antiatherogenic role for LRP5 was demonstrated as HC LRP5(-/-) mice developed larger aortic atherosclerotic lesions than WT mice. Our results show an anti-inflammatory, pro-survival role for LRP5 and the Wnt signaling pathway in peripheral blood leukocytes.

Intensity-modulated three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Mohan, Radhe

1996-01-01

Optimized intensity-modulated treatments one of the important advances in photon radiotherapy. Intensity modulation provides a greatly increased control over dose distributions. Such control can be maximally exploited to achieve significantly higher levels of conformation to the desired clinical objectives using sophisticated optimization techniques. Safe, rapid and efficient delivery of intensity-modulated treatments has become feasible using a dynamic multi-leaf collimator under computer control. The need for all other field shaping devices such as blocks, wedges and compensators is eliminated. Planning and delivery of intensity-modulated treatments is amenable to automation and development of class solutions for each treatment site and stage which can be implemented not only at major academic centers but on a wide scale. A typical treatment involving as many as 10 fields can be delivered in times shorter than much simpler conventional treatments. The main objective of the course is to give an overview of the current state of the art of planning and delivery methods of intensity-modulated treatments. Specifically, the following topics will be covered using representative optimized plans and treatments: 1. A typical procedure for planning and delivering an intensity-modulated treatment. 2. Quantitative definition of criteria (i.e., the objective function) of optimization of intensity-modulated treatments. Clinical relevance of objectives and the dependence of the quality of optimized intensity-modulated plans upon whether the objectives are stated purely in terms of simple dose or dose-volume criteria or whether they incorporate biological indices. 3. Importance of the lateral transport of radiation in the design of intensity-modulated treatments. Impact on dose homogeneity and the optimum choice of margins. 4. Use of intensity-modulated treatments in escalation of tumor dose for the same or lower normal tissue dose. Fractionation of intensity-modulated treatments

Intensity-modulated three-dimensional conformal radiotherapy

International Nuclear Information System (INIS)

Mohan, Radhe

1997-01-01

Optimized intensity-modulated treatments one of the important advances in photon radiotherapy. Intensity modulation provides a greatly increased control over dose distributions. Such control can be maximally exploited to achieve significantly higher levels of conformation to the desired clinical objectives using sophisticated optimization techniques. Safe, rapid and efficient delivery of intensity-modulated treatments has become feasible using a dynamic multi-leaf collimator under computer control. The need for all other field shaping devices such as blocks, wedges and compensators is eliminated. Planning and delivery of intensity-modulated treatments is amenable to automation and development of class solutions for each treatment site and stage which can be implemented not only at major academic centers but on a wide scale. A typical treatment involving as many as 10 fields can be delivered in times shorter than much simpler conventional treatments. The main objective of the course is to give an overview of the current state of the art of planning and delivery methods of intensity-modulated treatments. Specifically, the following topics will be covered using representative optimized plans and treatments: 1. A typical procedure for planning and delivering an intensity-modulated treatment. 2. Quantitative definition of criteria (i.e., the objective function) of optimization of intensity-modulated treatments. Clinical relevance of objectives and the dependence of the quality of optimized intensity-modulated plans upon whether the objectives are stated purely in terms of simple dose or dose-volume criteria or whether they incorporate biological indices. 3. Importance of the lateral transport of radiation in the design of intensity-modulated treatments. Impact on dose homogeneity and the optimum choice of margins. 4. Use of intensity-modulated treatments in escalation of tumor dose for the same or lower normal tissue dose. Fractionation of intensity-modulated treatments

The optimal configuration of photovoltaic module arrays based on adaptive switching controls

International Nuclear Information System (INIS)

Chao, Kuei-Hsiang; Lai, Pei-Lun; Liao, Bo-Jyun

2015-01-01

Highlights: • We propose a strategy for determining the optimal configuration of a PV array. • The proposed strategy was based on particle swarm optimization (PSO) method. • It can identify the optimal module array connection scheme in the event of shading. • It can also find the optimal connection of a PV array even in module malfunctions. - Abstract: This study proposes a strategy for determining the optimal configuration of photovoltaic (PV) module arrays in shading or malfunction conditions. This strategy was based on particle swarm optimization (PSO). If shading or malfunctions of the photovoltaic module array occur, the module array immediately undergoes adaptive reconfiguration to increase the power output of the PV power generation system. First, the maximal power generated at various irradiation levels and temperatures was recorded during normal array operation. Subsequently, the irradiation level and module temperature, regardless of operating conditions, were used to recall the maximal power previously recorded. This previous maximum was compared with the maximal power value obtained using the maximum power point tracker to assess whether the PV module array was experiencing shading or malfunctions. After determining that the array was experiencing shading or malfunctions, PSO was used to identify the optimal module array connection scheme in abnormal conditions, and connection switches were used to implement optimal array reconfiguration. Finally, experiments were conducted to assess the strategy for identifying the optimal reconfiguration of a PV module array in the event of shading or malfunctions

A RhABF2/Ferritin module affects rose (Rosa hybrida) petal dehydration tolerance and senescence by modulating iron levels.

Science.gov (United States)

Liu, Jitao; Fan, Youwei; Zou, Jing; Fang, Yiqun; Wang, Linghao; Wang, Meng; Jiang, Xinqiang; Liu, Yiqing; Gao, Junping; Zhang, Changqing

2017-12-01

Plants often develop the capacity to tolerate moderate and reversible environmental stresses, such as drought, and to re-establish normal development once the stress has been removed. An example of this phenomenon is provided by cut rose (Rosa hybrida) flowers, which experience typical reversible dehydration stresses during post-harvest handling after harvesting at the bud stages. The molecular mechanisms involved in rose flower dehydration tolerance are not known, however. Here, we characterized a dehydration- and abscisic acid (ABA)-induced ferritin gene (RhFer1). Dehydration-induced free ferrous iron (Fe 2+ ) is preferentially sequestered by RhFer1 and not transported outside of the petal cells, to restrict oxidative stresses during dehydration. Free Fe 2+ accumulation resulted in more serious oxidative stresses and the induction of genes encoding antioxidant enzyme in RhFer1-silenced petals, and poorer dehydration tolerance was observed compared with tobacco rattle virus (TRV) controls. We also determined that RhABF2, an AREB/ABF transcription factor involved in the ABA signaling pathway, can activate RhFer1 expression by directly binding to its promoter. The silencing of RhABF2 decreased dehydration tolerance and disrupted Fe homeostasis in rose petals during dehydration, as did the silencing of RhFer1. Although both RhFer1 and Fe transporter genes are induced during flower natural senescence in plants, the silencing of RhABF2 or RhFer1 accelerates the petal senescence processes. These results suggest that the regulatory module RhABF2/RhFer1 contributes to the maintenance of Fe levels and enhances dehydration tolerance through the action of RhFer1 locally sequestering free Fe 2+ under dehydration conditions, and plays synergistic roles with transporter genes during flower senescence. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Modules of co-regulated metabolites in turmeric (Curcuma longa) rhizome suggest the existence of biosynthetic modules in plant specialized metabolism.

Science.gov (United States)

Xie, Zhengzhi; Ma, Xiaoqiang; Gang, David R

2009-01-01

Turmeric is an excellent example of a plant that produces large numbers of metabolites from diverse metabolic pathways or networks. It is hypothesized that these metabolic pathways or networks contain biosynthetic modules, which lead to the formation of metabolite modules-groups of metabolites whose production is co-regulated and biosynthetically linked. To test whether such co-regulated metabolite modules do exist in this plant, metabolic profiling analysis was performed on turmeric rhizome samples that were collected from 16 different growth and development treatments, which had significant impacts on the levels of 249 volatile and non-volatile metabolites that were detected. Importantly, one of the many co-regulated metabolite modules that were indeed readily detected in this analysis contained the three major curcuminoids, whereas many other structurally related diarylheptanoids belonged to separate metabolite modules, as did groups of terpenoids. The existence of these co-regulated metabolite modules supported the hypothesis that the 3-methoxyl groups on the aromatic rings of the curcuminoids are formed before the formation of the heptanoid backbone during the biosynthesis of curcumin and also suggested the involvement of multiple polyketide synthases with different substrate selectivities in the formation of the array of diarylheptanoids detected in turmeric. Similar conclusions about terpenoid biosynthesis could also be made. Thus, discovery and analysis of metabolite modules can be a powerful predictive tool in efforts to understand metabolism in plants.

Emission Spectrum Property of Modulated Atom-Field Coupling System

International Nuclear Information System (INIS)

Gao Yun-Feng; Feng Jian; Li Yue-Ke

2013-01-01

The emission spectrum of a two-level atom interacting with a single mode radiation field in the case of periodic oscillation coupling coefficient is investigated. A general expression for the emission spectrum is derived. The numerical results for the initial field in pure number stare are calculated. It is found that the effect of the coupling coefficient modulation on the spectral structure is very obvious in the case of a low modulation frequency and larger amplitude when the initial field is vacuum, which is potentially useful for exploring a modulated light source. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

Human Milk and Donkey Milk, Compared to Cow Milk, Reduce Inflammatory Mediators and Modulate Glucose and Lipid Metabolism, Acting on Mitochondrial Function and Oleylethanolamide Levels in Rat Skeletal Muscle.

Science.gov (United States)

Trinchese, Giovanna; Cavaliere, Gina; De Filippo, Chiara; Aceto, Serena; Prisco, Marina; Chun, Jong Tai; Penna, Eduardo; Negri, Rossella; Muredda, Laura; Demurtas, Andrea; Banni, Sebastiano; Berni-Canani, Roberto; Mattace Raso, Giuseppina; Calignano, Antonio; Meli, Rosaria; Greco, Luigi; Crispino, Marianna; Mollica, Maria P

2018-01-01

Scope: Milk from various species differs in nutrient composition. In particular, human milk (HM) and donkey milk (DM) are characterized by a relative high level of triacylglycerol enriched in palmitic acid in sn-2 position. These dietary fats seem to exert beneficial nutritional properties through N-acylethanolamine tissue modulation. The aim of this study is to compare the effects of cow milk (CM), DM, and HM on inflammation and glucose and lipid metabolism, focusing on mitochondrial function, efficiency, and dynamics in skeletal muscle, which is the major determinant of resting metabolic rate. Moreover, we also evaluated the levels of endocannabinoids and N-acylethanolamines in liver and skeletal muscle, since tissue fatty acid profiles can be modulated by nutrient intervention. Procedures: To this aim, rats were fed with CM, DM, or HM for 4 weeks. Then, glucose tolerance and insulin resistance were analyzed. Pro-inflammatory and anti-inflammatory cytokines were evaluated in serum and skeletal muscle. Skeletal muscle was also processed to estimate mitochondrial function, efficiency, and dynamics, oxidative stress, and antioxidant/detoxifying enzyme activities. Fatty acid profiles, endocannabinoids, and N-acylethanolamine congeners were determined in liver and skeletal muscle tissue. Results: We demonstrated that DM or HM administration reducing inflammation status, improves glucose disposal and insulin resistance and reduces lipid accumulation in skeletal muscle. Moreover, HM or DM administration increases redox status, and mitochondrial uncoupling, affecting mitochondrial dynamics in the skeletal muscle. Interestingly, HM and DM supplementation increase liver and muscle levels of the N-oleoylethanolamine (OEA), a key regulator of lipid metabolism and inflammation. Conclusions: HM and DM have a healthy nutritional effect, acting on inflammatory factors and glucose and lipid metabolism. This beneficial effect is associated to a modulation of mitochondrial function

Human Milk and Donkey Milk, Compared to Cow Milk, Reduce Inflammatory Mediators and Modulate Glucose and Lipid Metabolism, Acting on Mitochondrial Function and Oleylethanolamide Levels in Rat Skeletal Muscle

Directory of Open Access Journals (Sweden)

Giovanna Trinchese

2018-01-01

Full Text Available Scope: Milk from various species differs in nutrient composition. In particular, human milk (HM and donkey milk (DM are characterized by a relative high level of triacylglycerol enriched in palmitic acid in sn-2 position. These dietary fats seem to exert beneficial nutritional properties through N-acylethanolamine tissue modulation. The aim of this study is to compare the effects of cow milk (CM, DM, and HM on inflammation and glucose and lipid metabolism, focusing on mitochondrial function, efficiency, and dynamics in skeletal muscle, which is the major determinant of resting metabolic rate. Moreover, we also evaluated the levels of endocannabinoids and N-acylethanolamines in liver and skeletal muscle, since tissue fatty acid profiles can be modulated by nutrient intervention.Procedures: To this aim, rats were fed with CM, DM, or HM for 4 weeks. Then, glucose tolerance and insulin resistance were analyzed. Pro-inflammatory and anti-inflammatory cytokines were evaluated in serum and skeletal muscle. Skeletal muscle was also processed to estimate mitochondrial function, efficiency, and dynamics, oxidative stress, and antioxidant/detoxifying enzyme activities. Fatty acid profiles, endocannabinoids, and N-acylethanolamine congeners were determined in liver and skeletal muscle tissue.Results: We demonstrated that DM or HM administration reducing inflammation status, improves glucose disposal and insulin resistance and reduces lipid accumulation in skeletal muscle. Moreover, HM or DM administration increases redox status, and mitochondrial uncoupling, affecting mitochondrial dynamics in the skeletal muscle. Interestingly, HM and DM supplementation increase liver and muscle levels of the N-oleoylethanolamine (OEA, a key regulator of lipid metabolism and inflammation.Conclusions: HM and DM have a healthy nutritional effect, acting on inflammatory factors and glucose and lipid metabolism. This beneficial effect is associated to a modulation of

Modelling modulation perception : modulation low-pass filter or modulation filter bank?

NARCIS (Netherlands)

Dau, T.; Kollmeier, B.; Kohlrausch, A.G.

1995-01-01

In current models of modulation perception, the stimuli are first filtered and nonlinearly transformed (mostly half-wave rectified). In order to model the low-pass characteristic of measured modulation transfer functions, the next stage in the models is a first-order low-pass filter with a typical

All-optical modulation based on electromagnetically induced transparency

International Nuclear Information System (INIS)

Fountoulakis, Antonios; Terzis, Andreas F.; Paspalakis, Emmanuel

2010-01-01

We numerically investigate the implementation of all-optical absorption modulation of electromagnetic pulses by a medium that exhibits electromagnetically induced transparency. The quantum system is modelled as a three-level Λ-type system that interacts with two electromagnetic pulses, a probe pulse and a coupling pulse. The dynamics of the system is described by the coupled Maxwell-density matrix equations, and we explore the dependence of the optical modulation efficiency on the parameters of the system.

Cost and Potential of Monolithic CIGS Photovoltaic Modules

Energy Technology Data Exchange (ETDEWEB)

Horowitz, Kelsey; Woodhouse, Michael

2015-06-17

A bottom-up cost analysis of monolithic, glass-glass Cu(In,Ga)(Se,S)2 (CIGS) modules is presented, illuminating current cost drivers for this technology and possible pathways to reduced cost. At 14% module efficiency, for the case of U.S. manufacturing, a manufacturing cost of $0.56/WDC and a minimum sustainable price of $0.72/WDC were calculated. Potential for reduction in manufacturing costs to below $0.40/WDC in the long-term may be possible if module efficiency can be increased without significant increase in $/m2 costs. The levelized cost of energy (LCOE) in Phoenix, AZ under different conditions is assessed and compared to standard c-Si.

Dynamic range of frontoparietal functional modulation is associated with working memory capacity limitations in older adults.

Science.gov (United States)

Hakun, Jonathan G; Johnson, Nathan F

2017-11-01

Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60-77years of age), age was negatively associated with frontoparietal modulation range. Individuals with greater modulation range exhibited more accurate N-Back performance. In addition, despite a lack of significant relationships between N-Back and complex span task performance, range of frontoparietal modulation during the N-Back significantly predicted domain-general estimates of WM capacity. Consistent with previous cross-sectional findings, older individuals with less modulation range exhibited greater activation at the lowest level of task difficulty but less activation at the highest levels of task difficulty. Our results are largely consistent with existing theories of neurocognitive aging (e.g. CRUNCH) but focus attention on dynamic range of functional modulation asa novel marker of WM capacity-limitations in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.

Genome-wide identification of key modulators of gene-gene interaction networks in breast cancer.

Science.gov (United States)

Chiu, Yu-Chiao; Wang, Li-Ju; Hsiao, Tzu-Hung; Chuang, Eric Y; Chen, Yidong

2017-10-03

With the advances in high-throughput gene profiling technologies, a large volume of gene interaction maps has been constructed. A higher-level layer of gene-gene interaction, namely modulate gene interaction, is composed of gene pairs of which interaction strengths are modulated by (i.e., dependent on) the expression level of a key modulator gene. Systematic investigations into the modulation by estrogen receptor (ER), the best-known modulator gene, have revealed the functional and prognostic significance in breast cancer. However, a genome-wide identification of key modulator genes that may further unveil the landscape of modulated gene interaction is still lacking. We proposed a systematic workflow to screen for key modulators based on genome-wide gene expression profiles. We designed four modularity parameters to measure the ability of a putative modulator to perturb gene interaction networks. Applying the method to a dataset of 286 breast tumors, we comprehensively characterized the modularity parameters and identified a total of 973 key modulator genes. The modularity of these modulators was verified in three independent breast cancer datasets. ESR1, the encoding gene of ER, appeared in the list, and abundant novel modulators were illuminated. For instance, a prognostic predictor of breast cancer, SFRP1, was found the second modulator. Functional annotation analysis of the 973 modulators revealed involvements in ER-related cellular processes as well as immune- and tumor-associated functions. Here we present, as far as we know, the first comprehensive analysis of key modulator genes on a genome-wide scale. The validity of filtering parameters as well as the conservativity of modulators among cohorts were corroborated. Our data bring new insights into the modulated layer of gene-gene interaction and provide candidates for further biological investigations.

A comparison of ROChem reverse osmosis and spiral wound reverse osmosis membrane modules

International Nuclear Information System (INIS)

Siler, J.L.

1992-01-01

Testing of the ROChem Disc Tube reg-sign reverse osmosis (RO) module's performance on biologically active feed waters has been completed. Both the ROChem module (using Filmtec standard-rejection seawater membranes) and the Filmtec spiral-wound membrane module (using Filmtec high-rejection seawater membranes) were tested with stimulant solutions containing typical bacteria and metal hydroxide levels found in the F/H Effluent Treatment Facility (ETF) influent. Results indicate that the ROChem module gave superior performance over the spiral-wound module. Water flux losses were reduced by over 30% for water recoveries above 40%

Negative voltage modulated multi-level resistive switching by using a Cr/BaTiOx/TiN structure and quantum conductance through evidence of H2O2 sensing mechanism.

Science.gov (United States)

Chakrabarti, Somsubhra; Ginnaram, Sreekanth; Jana, Surajit; Wu, Zong-Yi; Singh, Kanishk; Roy, Anisha; Kumar, Pankaj; Maikap, Siddheswar; Qiu, Jian-Tai; Cheng, Hsin-Ming; Tsai, Ling-Na; Chang, Ya-Ling; Mahapatra, Rajat; Yang, Jer-Ren

2017-07-05

Negative voltage modulated multi-level resistive switching with quantum conductance during staircase-type RESET and its transport characteristics in Cr/BaTiO x /TiN structure have been investigated for the first time. The as-deposited amorphous BaTiO x film has been confirmed by high-resolution transmission electron microscopy. X-ray photo-electron spectroscopy shows different oxidation states of Ba in the switching material, which is responsible for tunable more than 10 resistance states by varying negative stop voltage owing to slow decay value of RESET slope (217.39 mV/decade). Quantum conductance phenomenon has been observed in staircase RESET cycle of the memory devices. By inspecting the oxidation states of Ba + and Ba 2+ through measuring H 2 O 2 with a low concentration of 1 nM in electrolyte/BaTiO x /SiO 2 /p-Si structure, the switching mechanism of each HRS level as well as the multi-level phenomenon has been explained by gradual dissolution of oxygen vacancy filament. Along with negative stop voltage modulated multi-level, current compliance dependent multi-level has also been demonstrated and resistance ratio up to 2000 has been achieved even for a thin (voltage switching curve has been simulated as well. Hence, multi-level resistive switching of Cr/BaTiO x /TiN structure implies the promising applications in high dense, multistate non-volatile memories in near future.

Development of a NIM module for time-to-digital conversion

International Nuclear Information System (INIS)

Lin Yanchang; Wang Xiaobin; Chen Shaomin; Gao Yuanning; Jiang Chunhua; Qian Wenbin

2008-01-01

A developed single slot wide NIM module for time-to-digital conversion (TDC) is presented in this paper. This TDC module consists of a CPLD based double edge trigger counter with logic function circuit, a high speed comparator based NIM-to-TTL logic level converter, a processor ARM based data access and communication control unit, and voltage regulators for power supply. There are two input groups available, separately for accepting start and stop signal between two input ports or just from the same input port in sequence. With a 50 MHz reference clock, the available input ranges from 0 to 81.91 μs, and the resolution can reach 10 ns level. This module was tested in a muon lifetime measurement experiment, showing good linearity, simple configuration, low power consumption, good reliability, low cost, and easy upgrade as well. (authors)

Phase modulated high density collinear holographic data storage system with phase-retrieval reference beam locking and orthogonal reference encoding.

Science.gov (United States)

Liu, Jinpeng; Horimai, Hideyoshi; Lin, Xiao; Huang, Yong; Tan, Xiaodi

2018-02-19

A novel phase modulation method for holographic data storage with phase-retrieval reference beam locking is proposed and incorporated into an amplitude-encoding collinear holographic storage system. Unlike the conventional phase retrieval method, the proposed method locks the data page and the corresponding phase-retrieval interference beam together at the same location with a sequential recording process, which eliminates piezoelectric elements, phase shift arrays and extra interference beams, making the system more compact and phase retrieval easier. To evaluate our proposed phase modulation method, we recorded and then recovered data pages with multilevel phase modulation using two spatial light modulators experimentally. For 4-level, 8-level, and 16-level phase modulation, we achieved the bit error rate (BER) of 0.3%, 1.5% and 6.6% respectively. To further improve data storage density, an orthogonal reference encoding multiplexing method at the same position of medium is also proposed and validated experimentally. We increased the code rate of pure 3/16 amplitude encoding method from 0.5 up to 1.0 and 1.5 using 4-level and 8-level phase modulation respectively.

High repetition rate driver circuit for modulation of injection lasers

International Nuclear Information System (INIS)

Dornan, B.R.; Goel, J.; Wolkstein, H.J.

1981-01-01

An injection laser modulator comprises a self-biased field effect transistor (FET) and an injection laser to provide a quiescent state during which lasing of the injection laser occurs in response to a high repetition rate signal of pulse coded modulation (pcm). The modulator is d.c. coupled to an input pulse source of pcm rendering it compatible with an input pulse referenced to ground and not being subject to voltage level shifting of the input pulse. The modulator circuit in its preferred and alternate embodiments provides various arrangements for high impedance input and low impedance output matching. In addition, means are provided for adjusting the bias of the FET as well as the bias of the injection laser

Distraction task rather than focal attention modulates gamma activity associated with auditory steady-state responses (ASSRs)

DEFF Research Database (Denmark)

Griskova-Bulanova, Inga; Ruksenas, Osvaldas; Dapsys, Kastytis

2011-01-01

To explore the modulation of auditory steady-state response (ASSR) by experimental tasks, differing in attentional focus and arousal level.......To explore the modulation of auditory steady-state response (ASSR) by experimental tasks, differing in attentional focus and arousal level....

Mutually-modulated cross-gain modulation and slow light

International Nuclear Information System (INIS)

Sternklar, Shmuel; Sarid, Eyal; Wart, Maxim; Granot, Er'el

2010-01-01

The interaction of pump and Stokes light in a Brillouin medium, where both beams are modulated, can be utilized for controlling the group velocity of the amplified Stokes (or depleted pump). The dependence of the group velocity for this mutually-modulated cross-gain modulation (MMXGM) technique on the Brillouin gain parameter is studied. A sharp transition to slow light occurs in the G 1 α/β≈1 regime, where G 1 is the Brillouin gain parameter, and α and β are the pump and Stokes modulation indices, respectively. A comparison of MMXGM slow light to the Brillouin dispersion-based slow-light technique reveals the fundamental differences between them. The formation of higher harmonics of the modulation frequency is also discussed. The theoretical predictions are experimentally corroborated and potential applications in fiber-based sensing and interferometry are discussed

WRAP Module 1 sampling and analysis plan

Energy Technology Data Exchange (ETDEWEB)

Mayancsik, B.A.

1995-03-24

This document provides the methodology to sample, screen, and analyze waste generated, processed, or otherwise the responsibility of the Waste Receiving and Processing Module 1 facility. This includes Low-Level Waste, Transuranic Waste, Mixed Waste, and Dangerous Waste.

WRAP Module 1 sampling and analysis plan

International Nuclear Information System (INIS)

Mayancsik, B.A.

1995-01-01

This document provides the methodology to sample, screen, and analyze waste generated, processed, or otherwise the responsibility of the Waste Receiving and Processing Module 1 facility. This includes Low-Level Waste, Transuranic Waste, Mixed Waste, and Dangerous Waste

Electroabsorption optical modulator

Energy Technology Data Exchange (ETDEWEB)

Skogen, Erik J.

2017-11-21

An electroabsorption modulator incorporates waveguiding regions along the length of the modulator that include quantum wells where at least two of the regions have quantum wells with different bandgaps. In one embodiment of the invention, the regions are arranged such that the quantum wells have bandgaps with decreasing bandgap energy along the length of the modulator from the modulator's input to its output. The bandgap energy of the quantum wells may be decreased in discrete steps or continuously. Advantageously, such an arrangement better distributes the optical absorption as well as the carrier density along the length of the modulator. Further advantageously, the modulator may handle increased optical power as compared with prior art modulators of similar dimensions, which allows for improved link gain when the optical modulator is used in an analog optical communication link.

Processing module operating methods, processing modules, and communications systems

Science.gov (United States)

McCown, Steven Harvey; Derr, Kurt W.; Moore, Troy

2014-09-09

A processing module operating method includes using a processing module physically connected to a wireless communications device, requesting that the wireless communications device retrieve encrypted code from a web site and receiving the encrypted code from the wireless communications device. The wireless communications device is unable to decrypt the encrypted code. The method further includes using the processing module, decrypting the encrypted code, executing the decrypted code, and preventing the wireless communications device from accessing the decrypted code. Another processing module operating method includes using a processing module physically connected to a host device, executing an application within the processing module, allowing the application to exchange user interaction data communicated using a user interface of the host device with the host device, and allowing the application to use the host device as a communications device for exchanging information with a remote device distinct from the host device.

Automatic tube-current modulation in CT - A comparison between different solutions

International Nuclear Information System (INIS)

Althen, J. N.

2005-01-01

In this study, tube-current modulation systems on two different CT equipments have been evaluated: Care Dose from Siemens and Auto mA from GE Medical Systems. Care Dose modulates the tube current in the xy-plane during rotation whereas Auto mA modulates the tube current in the z-direction. xy-Plane modulation was investigated by using an elliptic Poly-methylmethacrylate phantom and a CTDI-ion chamber. To investigate modulation in the z-direction, an anthropomorphic dosimetry phantom (Atom) was used. Tests performed with and without tube-current modulation were compared with respect to absorbed dose and image quality. In the anthropomorphic phantom measurements, the dose savings were 15% using Care Dose and the photon starvation artefacts were negligible. Using Auto mA the absorbed dose depends on the chosen noise level. Image noise becomes more constant throughout the patient but photon starvation artefacts remain. We conclude that the two tube-current modulation techniques show different dose advantages and image quality artefacts. (authors)

Vocational education training in environmental health sciences: using ionizing radiation detectors, module 11

International Nuclear Information System (INIS)

May, F.C.

1981-07-01

In this instructional module, students learn to operate a geiger counter and read a pocket ion chamber dosimeter in demonstrating how radiation levels are affected by distance, shielding, and time. Training Prerequisites: Before beginning this module, students should be, or have been, enrolled in a course on radiation safety or its equivalent at the 2-year technical-school or college level. Upon completion of this module, students will be able to perform the following functions: (1) Name and tell the function of the major components of a geiger counter and check its operation using a sealed check source of low radioactivity. (2) Read a pocket ion chamber dosimeter and recharge the dosimeter using a dosimeter charger. (3) Demonstrate what effects distance, shielding, and time have on radiation levels

Onsite storage facility for low level radwaste

International Nuclear Information System (INIS)

Maxwell, M.G.

1984-01-01

The Tennessee Valley Authority (TVA) has designed and constructed an onsite storage facility for low level radwaste (LLRW) at its Browns Ferry Nuclear Plant in northern Alabama. The paper addresses the function of this facility and provides a complete description of the reinforced concrete storage modules which are the principal structural elements of the facility. The loads and loading combinations for the design of the storage modules are defined to include the foundation design parameters. Other aspects of the modules that are addressed are; the structural roof elements that provide access to the modules, shielding requirements for the LLRW, and tornado missile considerations

Level-1 Calorimeter Trigger starts firing

CERN Multimedia

Stephen Hillier

2007-01-01

L1Calo is one of the major components of ATLAS First Level trigger, along with the Muon Trigger and Central Trigger Processor. It forms all of the first-level calorimeter-based triggers, including electron, jet, tau and missing ET. The final system consists of over 250 custom designed 9U VME boards, most containing a dense array of FPGAs or ASICs. It is subdivided into a PreProcessor, which digitises the incoming trigger signals from the Liquid Argon and Tile calorimeters, and two separate processor systems, which perform the physics algorithms. All of these are highly flexible, allowing the possibility to adapt to beam conditions and luminosity. All parts of the system are read out through Read-Out Drivers, which provide monitoring data and Region of Interest (RoI) information for the Level-2 trigger. Production of the modules is now essentially complete, and enough modules exist to populate the full scale system in USA15. Installation is proceeding rapidly - approximately 90% of the final modules are insta...

Single-Carrier Modulation for Neutral-Point-Clamped Inverters in Three-Phase Transformerless Photovoltaic Systems

DEFF Research Database (Denmark)

Guo, Xiaoqiang; Cavalcanti, Marcelo C.; Farias, Alexandre M.

2013-01-01

Modulation strategy is one of the most important issues for three-level neutral-point-clamped inverters in three-phase transformerless photovoltaic systems. A challenge for modulation is how to keep the common-mode voltages constant to reduce the leakage currents. A single-carrier modulation...... strategy is proposed. It has a very simple structure, and the common-mode voltages can be kept constant with no need of complex space-vector modulation or multicarrier pulsewidth modulation. Experimental results verify the theoretical analysis and the effectiveness of the presented method....

Attention-related modulation of auditory brainstem responses during contralateral noise exposure.

Science.gov (United States)

Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

2008-10-29

As determinants facilitating attention-related modulation of the auditory brainstem response (ABR), two experimental factors were examined: (i) auditory discrimination; and (ii) contralateral masking intensity. Tone pips at 80 dB sound pressure level were presented to the left ear via either single-tone exposures or oddball exposures, whereas white noise was delivered continuously to the right ear at variable intensities (none--80 dB sound pressure level). Participants each conducted two tasks during stimulation, either reading a book (ignoring task) or detecting target tones (attentive task). Task-related modulation within the ABR range was found only during oddball exposures at contralateral masking intensities greater than or equal to 60 dB. Attention-related modulation of ABR can thus be detected reliably during auditory discrimination under contralateral masking of sufficient intensity.

Concentrated pitch discrimination modulates auditory brainstem responses during contralateral noise exposure.

Science.gov (United States)

Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

2010-03-31

This study examined a notion that auditory discrimination is a requisite for attention-related modulation of the auditory brainstem response (ABR) during contralateral noise exposure. Given that the right ear was exposed continuously with white noise at an intensity of 60-80 dB sound pressure level, tone pips at 80 dB sound pressure level were delivered to the left ear through either single-stimulus or oddball procedures. Participants conducted reading (ignoring task) and counting target tones (attentive task) during stimulation. The oddball but not the single-stimulus procedures elicited task-related modulations in both early (ABR) and late (processing negativity) event-related potentials simultaneously. The elicitation of the attention-related ABR modulation during contralateral noise exposure is thus considered to require auditory discrimination and have the corticofugal nature evidently.

Amplitude modulation of sound from wind turbines under various meteorological conditions.

Science.gov (United States)

Larsson, Conny; Öhlund, Olof

2014-01-01

Wind turbine (WT) sound annoys some people even though the sound levels are relatively low. This could be because of the amplitude modulated "swishing" characteristic of the turbine sound, which is not taken into account by standard procedures for measuring average sound levels. Studies of sound immission from WTs were conducted continually between 19 August 2011 and 19 August 2012 at two sites in Sweden. A method for quantifying the degree and strength of amplitude modulation (AM) is introduced here. The method reveals that AM at the immission points occur under specific meteorological conditions. For WT sound immission, the wind direction and sound speed gradient are crucial for the occurrence of AM. Interference between two or more WTs could probably enhance AM. The mechanisms by which WT sound is amplitude modulated are not fully understood.

Investigation of the feasibility of elective irradiation to neck level Ib using intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma: a retrospective analysis

International Nuclear Information System (INIS)

Zhang, Fan; Cheng, Yi-Kan; Li, Wen-Fei; Guo, Rui; Chen, Lei; Sun, Ying; Mao, Yan-Ping; Zhou, Guan-Qun; Liu, Xu; Liu, Li-Zhi; Lin, Ai-Hua; Tang, Ling-Long; Ma, Jun

2015-01-01

To assess the feasibility of elective neck irradiation to level Ib in nasopharyngeal carcinoma (NPC) using intensity-modulated radiation therapy (IMRT). We retrospectively analyzed 1438 patients with newly-diagnosed, non-metastatic and biopsy-proven NPC treated with IMRT. Greatest dimension of level IIa LNs (DLN-IIa) ≥ 20 mm and/or level IIa LNs with extracapsular spread (ES), oropharynx involvement and positive bilateral cervical lymph nodes (CLNs) were independently significantly associated with metastasis to level Ib LN at diagnosis. No recurrence at level Ib was observed in the 904 patients without these characteristics (median follow-up, 38.7 months; range, 1.3–57.8 months), these patients were classified as low risk. Level Ib irradiation was not an independent risk factor for locoregional failure-free survival, distant failure-free survival, failure-free survival or overall survival in low risk patients. The frequency of grade ≥ 2 subjective xerostomia at 12 months after radiotherapy was not significantly different between low risk patients who received level Ib-sparing, unilateral level Ib-covering or bilateral level Ib-covering IMRT. Level Ib-sparing IMRT should be safe and feasible for patients without a DLN-IIa ≥ 20 mm and/or level IIa LNs with ES, positive bilateral CLNs or oropharynx involvement at diagnosis. Further investigations based on specific criteria for dose constraints for the submandibular glands are warranted to confirm the benefit of elective level Ib irradiation

Chronic inflammation modulates ghrelin levels in humans and rats.

Science.gov (United States)

Otero, M; Nogueiras, R; Lago, F; Dieguez, C; Gomez-Reino, J J; Gualillo, O

2004-03-01

The aim of this work was to investigate whether changes in plasma ghrelin, the recently discovered 28-amino acid gastric hormone that regulates growth hormone (GH) secretion and energy homeostasis, occur during inflammation in adjuvant-induced arthritis (AA) in rats. For completeness, ghrelin plasma levels were measured in rheumatoid arthritis (RA) patients. AA was induced in male Lewis rats using Freund's complete adjuvant. Animals were monitored for weight and food intake, every 2 or 3 days, along all time-course experiments. Plasma ghrelin concentrations in 31 RA patients and 18 healthy controls, as well as in rats, were determined by a specific double-antibody radioimmunoassay. Gastric ghrelin mRNA expression was evaluated by northern blot analysis. Human GH and insulin-like growth factor (IGF)-1 were determined by quantitative chemiluminescence assay. Compared with controls, arthritic rats gained significantly (P Ghrelin plasma levels were significantly lower at day 7 after arthritis induction than in controls (AA 7 = 91.2 +/- 5.6 pg/ml vs controls = 124.75 +/- 5.9 pg/ml), but they recovered to control levels by day 15. RA patients had ghrelin plasma levels significantly lower than healthy controls (RA = 24.54 +/- 2.57 pg/ml vs 39.01 +/- 4.47 pg/ml of healthy controls; P = 0.0041). In AA, there is a compensatory variation of ghrelin levels that relates to body weight adjustments. Recovery of ghrelin levels in the latter stage suggests an adaptive response and may represent a compensatory mechanism under catabolic conditions. In RA patients, chronic imbalance in ghrelin levels suggests that this gastric hormone may participate, together with other factors, in alterations of metabolic status during inflammatory stress.

STUDIES ON IGBT MODULE TO IMPROVE THE RELIABILITY OF POWER ELECTRONIC SYSTEMS

DEFF Research Database (Denmark)

Choi, Uimin

component level to converter level. It is divided into two main parts: the first part, which consists of Chapters 2 and 3, is reliability studies of the IGBT module regarding thermal stresses and the second part, composed of Chapters 4 and 5, discusses strategies to improve the reliability and availability...... are presented. Then, in Chapter 3, the effect of junction temperature swing duration t△Tj on the lifetime of the transfer molded Intelligent Power IGBT Module is investigated and modeled based on the power cycling test results. In addition, the physics-of-failure analysis results of the tested modules...... are presented. Finally, in Chapters 4 and 5, open-circuit fault detection and fault-tolerant control methods are proposed for two kinds of neutral-point clamped three-level inverters T-type and NPC inverters. One of main contributions in this project is the development of an apparatus and methodology...

Enhanced Buck-Boost Three-Level Neutral-Point-Clamped Inverters

DEFF Research Database (Denmark)

Tan, K. K.; Gao, F.; Chiang Loh, Poh

2009-01-01

In traditional three-level neutral-point-clamped (NPC) inverters, a major issue is capacitor voltage imbalance, which results in low order harmonics. The compensation of the capacitor voltages often require additional control complexity, which cannot be conveniently implemented. The "alternative...... phase opposition disposition" (APOD) modulation method used in traditional NPC topologies also has lower harmonics performance as compared to the "phase disposition" (PD) modulation method.In this paper, we introduce a new three-level NPC topology that utilises the harmonically superior PD modulation...... method, with the ability to easily adjust for capacitor voltage imbalances. To further improve the boost capability of the three-level NPC inverters, another new topology introduces 2 additional diodes,achieving higher boost performance while totally eliminating thepossibility of capacitor voltage...

Light Microscopy Module (LMM)-Emulator

Science.gov (United States)

Levine, Howard G.; Smith, Trent M.; Richards, Stephanie E.

2016-01-01

The Light Microscopy Module (LMM) is a microscope facility developed at Glenn Research Center (GRC) that provides researchers with powerful imaging capability onboard the International Space Station (ISS). LMM has the ability to have its hardware recongured on-orbit to accommodate a wide variety of investigations, with the capability of remotely acquiring and downloading digital images across multiple levels of magnication.

Standard Practice for Visual Inspections of Photovoltaic Modules

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 This practice covers procedures and criteria for visual inspections of photovoltaic modules. 1.2 Visual inspections of photovoltaic modules are normally performed before and after modules have been subjected to environmental, electrical, or mechanical stress testing, such as thermal cycling, humidity-freeze cycling, damp heat exposure, ultraviolet exposure, mechanical loading, hail impact testing, outdoor exposure, or other stress testing that may be part of photovoltaic module testing sequence. 1.3 This practice does not establish pass or fail levels. The determination of acceptable or unacceptable results is beyond the scope of this practice. 1.4 There is no similar or equivalent ISO standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Electrophysiological changes in rats after modulated microwave irradiation

International Nuclear Information System (INIS)

Szabo, L.D.; Thuroczy, G.; Kubinyi, G.; Bakos, J.

1992-01-01

The effects of modulated microwave irradiation on the electrophysiological changes in rats were studied. The response of the central nervous system (CNS) was observed simultaneously to the cardiovascular system by using quantitative polygraphic measuring system. In acute experiments on rat the electroencephalogram (EEG), rheoencephalogram (REG) as an index of cerebral blood flow (CBF), brain tissue DC impedance and temperature, ECG were recorded in parallel before, during and after exposure of the brain localized amplitude (AM) modulated (16 Hz) and continuous wave (CW) microwave exposure. The average specific absorption rates (SAR) in the brain were 8.4 mW/g, 16.8 mW/g and 42 mW/g (CW) respectively. At thermal level CW exposure the delta band of EEG increased. In case of low intensities modulated exposure the beta band of EEG spectrum increased. No changes were observed during athermal CW irradiation on the EEG. Moderate modulation depended changes were measured in cerebral metabolism, cerebral blood flow and cardiorespiratoric system during microwave irradiation. (author)

Low-level contrast statistics of natural images can modulate the frequency of event-related potentials (ERP in humans

Directory of Open Access Journals (Sweden)

Masoud Ghodrati

2016-12-01

Full Text Available Humans are fast and accurate in categorizing complex natural images. It is, however, unclear what features of visual information are exploited by brain to perceive the images with such speed and accuracy. It has been shown that low-level contrast statistics of natural scenes can explain the variance of amplitude of event-related potentials (ERP in response to rapidly presented images. In this study, we investigated the effect of these statistics on frequency content of ERPs. We recorded ERPs from human subjects, while they viewed natural images each presented for 70 ms. Our results showed that Weibull contrast statistics, as a biologically plausible model, explained the variance of ERPs the best, compared to other image statistics that we assessed. Our time-frequency analysis revealed a significant correlation between these statistics and ERPs’ power within theta frequency band (~3-7 Hz. This is interesting, as theta band is believed to be involved in context updating and semantic encoding. This correlation became significant at ~110 ms after stimulus onset, and peaked at 138 ms. Our results show that not only the amplitude but also the frequency of neural responses can be modulated with low-level contrast statistics of natural images and highlights their potential role in scene perception.

A burn-up module coupling to an AMPX system

International Nuclear Information System (INIS)

Salvatore Duque, M.; Gomez, S.E.; Patino, N.E.; Abbate, M.J.; Sbaffoni, M.M.

1990-01-01

The Reactors and Neutrons Division of the Bariloche Atomic Center uses the AMPX system for the study of high conversion reactors (HCR). Such system allows to make neutronic calculations from the nuclear data library (ENDF/B-IV). The Nuclear Engineering career of the Balseiro Institute developed and implemented a burn-up module at a μ-cell level (BUM: Burn-up Module) which agrees with the requirement to be coupled to the AMPX system. (Author) [es

Responses to amplitude modulated infrared stimuli in the guinea pig inferior colliculus

Science.gov (United States)

Richter, Claus-Peter; Young, Hunter

2013-03-01

Responses of units in the central nucleus of the inferior colliculus of the guinea pig were recorded with tungsten electrodes. The set of data presented here is limited to high stimulus levels. The effect of changing the modulation frequency and the modulation depth was explored for acoustic and laser stimuli. The selected units responded to sinusoidal amplitude modulated (AM) tones, AM trains of clicks, and AM trains of laser pulses with a modulation of their spike discharge. At modulation frequencies of 20 Hz, some units tended to respond with 40 Hz to the acoustic stimuli, but only at 20 Hz for the trains of laser pulses. For all modes of stimulation the responses revealed a dominant response to the first cycle of the modulation, with decreasing number of action potential during successive cycles. While amplitude modulated tone bursts and amplitude modulated trains of acoustic clicks showed similar patterns, the response to trains of laser pulses was different.

Radio-frequency-modulated Rydberg states in a vapor cell

Science.gov (United States)

Miller, S. A.; Anderson, D. A.; Raithel, G.

2016-05-01

We measure strong radio-frequency (RF) electric fields using rubidium Rydberg atoms prepared in a room-temperature vapor cell as field sensors. Electromagnetically induced transparency is employed as an optical readout. We RF-modulate the 60{{{S}}}1/2 and 58{{{D}}}5/2 Rydberg states with 50 and 100 MHz fields, respectively. For weak to moderate RF fields, the Rydberg levels become Stark-shifted, and sidebands appear at even multiples of the driving frequency. In high fields, the adjacent hydrogenic manifold begins to intersect the shifted levels, providing rich spectroscopic structure suitable for precision field measurements. A quantitative description of strong-field level modulation and mixing of S and D states with hydrogenic states is provided by Floquet theory. Additionally, we estimate the shielding of DC electric fields in the interior of the glass vapor cell.

Simplified atom trap using a single microwave modulated diode laser

International Nuclear Information System (INIS)

Newbury, N.R.; Myatt, C.J.; Wieman, C.E.

1993-01-01

We have demonstrated microwave modulation of a diode laser which is operated with optical feedback from a diffraction grating. By directly modulating the diode laser current at frequencies up to 6.8 GHz, we observed 2-30% of the laser power in a single sideband for 20mW of microwave power. Using such a diode laser modulated at 6.6GHz, we have trapped 87 Rb in a vapor cell. With 10mW of microwave power, the number of trapped atoms was only 15% smaller than the number obtained using two lasers in the conventional manner. A microwave modulated diode laser should also be useful for driving stimulated Raman transitions between the hyperfine levels of Rb or Cs

Losses analysis of soft magnetic ring core under sinusoidal pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM) excitations

Science.gov (United States)

Gao, Hezhe; Li, Yongjian; Wang, Shanming; Zhu, Jianguo; Yang, Qingxin; Zhang, Changgeng; Li, Jingsong

2018-05-01

Practical core losses in electrical machines differ significantly from those experimental results using the standardized measurement method, i.e. Epstein Frame method. In order to obtain a better approximation of the losses in an electrical machine, a simulation method considering sinusoidal pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM) waveforms is proposed. The influence of the pulse width modulation (PWM) parameters on the harmonic components in SPWM and SVPWM is discussed by fast Fourier transform (FFT). Three-level SPWM and SVPWM are analyzed and compared both by simulation and experiment. The core losses of several ring samples magnetized by SPWM, SVPWM and sinusoidal alternating current (AC) are obtained. In addition, the temperature rise of the samples under SPWM, sinusoidal excitation are analyzed and compared.

Integrated systems and modules for engine cooling and vehicle air-conditioning; Integrierte Systeme und Module zur Motorkuehlung und Innenraumklimatisierung

Energy Technology Data Exchange (ETDEWEB)

Loehle, M.; Kern, J.; Kampf, H. [Behr GmbH (Germany)

1998-12-01

The high level of function and quality achieved today in modern vehicles cannot be simply increased by the isolated development of advanced single components alone. By contrast, the holistic optimization of systems opens up new potential. Modern cooling modules and integrated HVAC systems by Behr GmbH and Co. combine several components to form a single compact module whose integrated parts are perfectly matched to each other. Developing complete cockpits at such a high level of integration is another step towards advancing the system concept. Understanding a holistic system allows engineers to develop concepts for an efficient thermal management in the cooling system and to improve ecological compatibility of the vehicle air-conditioning system by using suitable simulation tools. (orig.) [Deutsch] Die gesamtheitliche Optimierung von Systemen eroeffnet neue Potentiale in der Automobilentwicklung. Moderne Kuehlmodule und integrierte Heiz-/Klimageraete der Behr GmbH and Co. fassen zahlreiche Komponenten zu einem kompakten Modul zusammen, dessen Einzelteile aufeinander abgestimmt sind. Die Entwicklung vollstaendiger Cockpits mit einem hohen Integrationsgrad fuehrt den Systemgedanken konsequent weiter. Das Verstaendnis des gesamten Systems erlaubt im Verbund mit geeigneten Simulationswerkzeugen die Entwicklung von Konzepten fuer ein effizientes Thermomanagement im Kuehlsystem und fuer die Verbesserung der Umweltvertraeglichkeit der Kaelteanlage. (orig.)

MET-RODOS: A comprehensive atmospheric dispersion module

DEFF Research Database (Denmark)

Mikkelsen, T.; Thykier-Nielsen, S.; Astrup, P.

1997-01-01

A comprehensive meteorological dispersion module called MET-RODOS is being developed to serve the real-time RODOS(1-3) decision support system with an integrated prediction capability for airborne radioactive spread, deposition and gamma radiation exposure on all scales. Deposition, ground level ...

Thermo-Mechanical tests for the CLIC two-beam module study

CERN Document Server

Xydou, A; Riddone, G; Daskalaki, E

2014-01-01

The luminosity goal of CLIC requires micron level precision with respect to the alignment of the components on its two-meter long modules, composing the two main linacs. The power dissipated inside the module components introduces mechanical deformations affecting their alignment and therefore the resulting machine performance. Several two-beam prototype modules must be assembled to extensively measure their thermo-mechanical behavior under different operation modes. In parallel, the real environmental conditions present in the CLIC tunnel should be studied. The air conditioning and ventilation system providing specified air temperature and flow has been installed in the dedicated laboratory. The power dissipation occurring in the modules is being reproduced by the electrical heaters inserted inside the RF structure mock-ups and the quadrupoles. The efficiency of the cooling systems is being verified and the alignment of module components is monitored. The measurement results will be compared to finite elemen...

Practical design approach for trapezoidal modulation of a radio-frequency quadrupole

Directory of Open Access Journals (Sweden)

A. S. Plastun

2018-03-01

Full Text Available Trapezoidal modulation of quadrupole electrodes offers additional benefits to the concept of a radio-frequency quadrupole (RFQ. Because of the significant increase of the effective shunt impedance, RFQs with trapezoidal modulation have a reduced interelectrode voltage or resonator length as compared to conventional RFQs with sinusoidal modulation. This feature is especially valuable for RFQs operating in cw mode, since it reduces the required rf power. We develop a detailed procedure for the design of RFQ electrodes with trapezoidal modulation. With our design procedure and by properly choosing the trapezoidal cell parameters, we can easily control the peak surface fields in the RFQ to the same level as for sinusoidal cell modulation. The procedure is applied to the design of the electrodes for the ReA3 RFQ at Michigan State University.

CTG repeat-targeting oligonucleotides for down-regulating Huntingtin expression

DEFF Research Database (Denmark)

Zaghloul, Eman M; Gissberg, Olof; Moreno, Pedro M D

2017-01-01

Huntington's disease (HD) is a fatal, neurodegenerative disorder in which patients suffer from mobility, psychological and cognitive impairments. Existing therapeutics are only symptomatic and do not significantly alter the disease progression or increase life expectancy. HD is caused by expansion....... Thus, reduction of both muHTT mRNA and protein levels would ideally be the most useful therapeutic option. We herein present a novel strategy for HD treatment using oligonucleotides (ONs) directly targeting the HTT trinucleotide repeat DNA. A partial, but significant and potentially long-term, HTT...

Intermittent fasting modulates IgA levels in the small intestine under intense stress: a mouse model.

Science.gov (United States)

Lara-Padilla, Eleazar; Godínez-Victoria, Marycarmen; Drago-Serrano, Maria Elisa; Reyna-Garfias, Humberto; Arciniega-Martínez, Ivonne Maciel; Abarca-Rojano, Edgar; Cruz-Hernández, Teresita Rocío; Campos-Rodríguez, Rafael

2015-08-15

Intermittent fasting prolongs the lifespan and unlike intense stress provides health benefits. Given the role of the immunoglobulin A (IgA) in the intestinal homeostasis, the aim of this study was to assess the impact of intermittent fasting plus intense stress on secretory IgA (SIgA) production and other mucosal parameters in the duodenum and ileum. Two groups of six mice, with intermittent fasting or fed ad libitum for 12weeks, were submitted to a session of intense stress by a bout of forced swimming. Unstressed ad libitum fed or intermittently fasted groups were included as controls. After sacrifice, we evaluated intestinal SIgA and plasma adrenal hormones, lamina propria IgA+ plasma-cells, mRNA expression of polymeric immunoglobulin receptor, α- and J-chains in the liver and intestinal mucosa, as well as pro- (tumor necrosis factor-α, interleukin-6 and Interferon-γ) and anti- (interleukin-2, -4, -10 and transforming growth factor-β) inflammatory cytokines in mucosal samples. Under intense stress, intermittent fasting down- or up-modulated the levels of most parameters in the duodenum and ileum, respectively while up-regulated corticosterone levels without affecting epinephrine. Our data suggest intermittent fasting plus intense stress elicited neuroendocrine pathways that differentially controlled IgA and pIgR expression in duodenum and ileum. These findings provide experimental foundations for a presumable impact of intermittent fasting under intense stress on the intestinal homeostasis or inflammation by triggering or reducing the IgA production in ileum or duodenum respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

Neuroactive steroids modulate HPA axis activity and cerebral brain-derived neurotrophic factor (BDNF) protein levels in adult male rats.

Science.gov (United States)

Naert, Gaëlle; Maurice, Tangui; Tapia-Arancibia, Lucia; Givalois, Laurent

2007-01-01

Depression is characterized by hypothalamo-pituitary-adrenocortical (HPA) axis hyperactivity. In this major mood disorder, neurosteroids and neurotrophins, particularly brain-derived neurotrophic factor (BDNF), seem to be implicated and have some antidepressant effects. BDNF is highly involved in regulation of the HPA axis, whereas neurosteroids effects have never been clearly established. In this systematic in vivo study, we showed that the principal neuroactive steroids, namely dehydroepiandrosterone (DHEA), pregnenolone (PREG) and their sulfate esters (DHEA-S and PREG-S), along with allopregnanolone (ALLO), stimulated HPA axis activity, while also modulating central BDNF contents. In detail, DHEA, DHEA-S, PREG, PREG-S and ALLO induced corticotropin-releasing hormone (CRH) and/or arginine vasopressin (AVP) synthesis and release at the hypothalamic level, thus enhancing plasma adrenocorticotropin hormone (ACTH) and corticosterone (CORT) concentrations. This stimulation of the HPA axis occurred concomitantly with BDNF modifications at the hippocampus, amygdala and hypothalamus levels. We showed that these neurosteroids induced rapid effects, probably via neurotransmitter receptors and delayed effects perhaps after metabolization in other neuroactive steroids. We highlighted that they had peripheral effects directly at the adrenal level by inducing CORT release, certainly after estrogenic metabolization. In addition, we showed that, at the dose used, only DHEA, DHEA-S and PREG-S had antidepressant effects. In conclusion, these results highly suggest that part of the HPA axis and antidepressant effects of neuroactive steroids could be mediated by BDNF, particularly at the amygdala level. They also suggest that neurosteroids effects on central BDNF could partially explain the trophic properties of these molecules.

The time course of attention modulation elicited by spatial uncertainty.

Science.gov (United States)

Huang, Dan; Liang, Huilou; Xue, Linyan; Wang, Meijian; Hu, Qiyi; Chen, Yao

2017-09-01

Uncertainty regarding the target location is an influential factor for spatial attention. Modulation in spatial uncertainty can lead to adjustments in attention scope and variations in attention effects. Hence, investigating spatial uncertainty modulation is important for understanding the underlying mechanism of spatial attention. However, the temporal dynamics of this modulation remains unclear. To evaluate the time course of spatial uncertainty modulation, we adopted a Posner-like attention orienting paradigm with central or peripheral cues. Different numbers of cues were used to indicate the potential locations of the target and thereby manipulate the spatial uncertainty level. The time interval between the onsets of the cue and the target (stimulus onset asynchrony, SOA) varied from 50 to 2000ms. We found that under central cueing, the effect of spatial uncertainty modulation could be detected from 200 to 2000ms after the presence of the cues. Under peripheral cueing, the effect of spatial uncertainty modulation was observed from 50 to 2000ms after cueing. Our results demonstrate that spatial uncertainty modulation produces robust and sustained effects on target detection speed. The time course of this modulation is influenced by the cueing method, which suggests that discrepant processing procedures are involved under different cueing conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lactobacillus rhamnosus ATCC 7469 exopolysaccharides synergizes with low level ionizing radiation to modulate signaling molecular targets in colorectal carcinogenesis in rats.

Science.gov (United States)

Zahran, Walid E; Elsonbaty, Sawsan M; Moawed, Fatma S M

2017-08-01

Combination therapy that targets cellular signaling pathway represents an alternative therapy for the treatment of colon cancer (CRC). The present study was therefore aimed to investigate the probable interaction of Lactobacillus rhamnosus ATCC 7469 exopolysaccharides (EPS) with low level ionizing γ radiation (γ-R) exposure against dimethylhydrazine (DMH)- induced colorectal carcinogenesis in rats. Colon cancer was induced with 20mg DMH/kg BW. Rats received daily by gastric gavage 100mg EPS/Kg BW concomitant with 1Gy γ-R over two months. Colonic oxidative and inflammatory stresses were assessed. The change in the expression of p-p38 MAPK, p-STAT3, β-catenin, NF-kB, COX-2 and iNOS was evaluated by western blotting and q-PCR. It was found that DMH treatment significantly induced colon oxidative injury accompanied by inflammatory disturbance along with increased protein expression of the targeted signaling factors p-p38 MAPK, p-STAT3 and β-catenin. The mRNA gene expression of NF-kB, COX-2 and iNOS was significantly higher in DMH-treated animals. It's worthy to note that colon tissues with DMH treatment showed significant dysplasia and anaplasia of the glandular mucosal lining epithelium with loses of goblet cells formation, pleomorphism in the cells and hyperchromachia in nuclei. Interestingly, EPS treatment with γ-R exposure showed statistically significant amelioration of the oxidative and inflammatory biomarkers with modulated signaling molecular factors accompanied by improved histological structure against DMH-induced CRC. In conclusion, our findings showed that Lactobacillus rhamnosus ATCC 7469 EPS with low level γ-R in synergistic interaction are efficacious control against CRC progression throughout the modulation of key signaling growth factors associated with inflammation via antioxidant mediated anti-inflammatory and anti-proliferative activities. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Auditory sensitivity to spectral modulation phase reversal as a function of modulation depth.

Science.gov (United States)

Buss, Emily; Grose, John

2018-01-01

The present study evaluated auditory sensitivity to spectral modulation by determining the modulation depth required to detect modulation phase reversal. This approach may be preferable to spectral modulation detection with a spectrally flat standard, since listeners appear unable to perform the task based on the detection of temporal modulation. While phase reversal thresholds are often evaluated by holding modulation depth constant and adjusting modulation rate, holding rate constant and adjusting modulation depth supports rate-specific assessment of modulation processing. Stimuli were pink noise samples, filtered into seven octave-wide bands (0.125-8 kHz) and spectrally modulated in dB. Experiment 1 measured performance as a function of modulation depth to determine appropriate units for adaptive threshold estimation. Experiment 2 compared thresholds in dB for modulation detection with a flat standard and modulation phase reversal; results supported the idea that temporal cues were available at high rates for the former but not the latter. Experiment 3 evaluated spectral modulation phase reversal thresholds for modulation that was restricted to either one or two neighboring bands. Flanking bands of unmodulated noise had a larger detrimental effect on one-band than two-band targets. Thresholds for high-rate modulation improved with increasing carrier frequency up to 2 kHz, whereas low-rate modulation appeared more consistent across frequency, particularly in the two-band condition. Experiment 4 measured spectral weights for spectral modulation phase reversal detection and found higher weights for bands in the spectral center of the stimulus than for the lowest (0.125 kHz) or highest (8 kHz) band. Experiment 5 compared performance for highly practiced and relatively naïve listeners, and found weak evidence of a larger practice effect at high than low spectral modulation rates. These results provide preliminary data for a task that may provide a better estimate of

Development of the module inspection system for new standardized radiation monitoring modules

International Nuclear Information System (INIS)

Furukawa, Masami; Shimizu, Kazuaki; Hiruta, Toshihito; Mizugaki, Toshio; Ohi, Yoshihiro; Chida, Tooru.

1994-10-01

This report mentions about the module inspection system which does the maintenance check of the monitoring modules adapted the new monitoring standard, as well as the result of the verification of the modules. The module inspection system is the automatic measurement system with the computer. The system can perform the functional and the characteristic examination of the monitoring modules, the calibration with radiation source and inspection report. In the verification of the monitoring module, three major items were tested, the adaptability for the new monitoring standard, the module functions and each characteristics. All items met the new monitoring standard. (author)

Reduced multiplication modules

Indian Academy of Sciences (India)

if M is a von Neumann regular module (VNM); i.e., every principal submodule of M is a summand submodule. Also if M is an injective R-module, then M is a VNM. Keywords. Multiplication module; reduced module; minimal prime submodule;. Zariski topology; extremally disconnected. 1. Introduction. In this paper all rings are ...

An Integrated Simulation Module for Cyber-Physical Automation Systems

Directory of Open Access Journals (Sweden)

Francesco Ferracuti

2016-05-01

Full Text Available The integration of Wireless Sensors Networks (WSNs into Cyber Physical Systems (CPSs is an important research problem to solve in order to increase the performances, safety, reliability and usability of wireless automation systems. Due to the complexity of real CPSs, emulators and simulators are often used to replace the real control devices and physical connections during the development stage. The most widespread simulators are free, open source, expandable, flexible and fully integrated into mathematical modeling tools; however, the connection at a physical level and the direct interaction with the real process via the WSN are only marginally tackled; moreover, the simulated wireless sensor motes are not able to generate the analogue output typically required for control purposes. A new simulation module for the control of a wireless cyber-physical system is proposed in this paper. The module integrates the COntiki OS JAva Simulator (COOJA, a cross-level wireless sensor network simulator, and the LabVIEW system design software from National Instruments. The proposed software module has been called “GILOO” (Graphical Integration of Labview and cOOja. It allows one to develop and to debug control strategies over the WSN both using virtual or real hardware modules, such as the National Instruments Real-Time Module platform, the CompactRio, the Supervisory Control And Data Acquisition (SCADA, etc. To test the proposed solution, we decided to integrate it with one of the most popular simulators, i.e., the Contiki OS, and wireless motes, i.e., the Sky mote. As a further contribution, the Contiki Sky DAC driver and a new “Advanced Sky GUI” have been proposed and tested in the COOJA Simulator in order to provide the possibility to develop control over the WSN. To test the performances of the proposed GILOO software module, several experimental tests have been made, and interesting preliminary results are reported. The GILOO module has been

An Integrated Simulation Module for Cyber-Physical Automation Systems.

Science.gov (United States)

Ferracuti, Francesco; Freddi, Alessandro; Monteriù, Andrea; Prist, Mariorosario

2016-05-05

The integration of Wireless Sensors Networks (WSNs) into Cyber Physical Systems (CPSs) is an important research problem to solve in order to increase the performances, safety, reliability and usability of wireless automation systems. Due to the complexity of real CPSs, emulators and simulators are often used to replace the real control devices and physical connections during the development stage. The most widespread simulators are free, open source, expandable, flexible and fully integrated into mathematical modeling tools; however, the connection at a physical level and the direct interaction with the real process via the WSN are only marginally tackled; moreover, the simulated wireless sensor motes are not able to generate the analogue output typically required for control purposes. A new simulation module for the control of a wireless cyber-physical system is proposed in this paper. The module integrates the COntiki OS JAva Simulator (COOJA), a cross-level wireless sensor network simulator, and the LabVIEW system design software from National Instruments. The proposed software module has been called "GILOO" (Graphical Integration of Labview and cOOja). It allows one to develop and to debug control strategies over the WSN both using virtual or real hardware modules, such as the National Instruments Real-Time Module platform, the CompactRio, the Supervisory Control And Data Acquisition (SCADA), etc. To test the proposed solution, we decided to integrate it with one of the most popular simulators, i.e., the Contiki OS, and wireless motes, i.e., the Sky mote. As a further contribution, the Contiki Sky DAC driver and a new "Advanced Sky GUI" have been proposed and tested in the COOJA Simulator in order to provide the possibility to develop control over the WSN. To test the performances of the proposed GILOO software module, several experimental tests have been made, and interesting preliminary results are reported. The GILOO module has been applied to a smart home

Enhancement of the static extinction ratio by using a dual-section distributed feedback laser integrated with an electro-absorption modulator

Science.gov (United States)

Cho, Chun-Hyung; Kim, Jongseong; Sung, Hyuk-Kee

2016-09-01

We report on the enhancement of the static extinction ratio by using a dual-section distributed feedback laser diode integrated with an electro-absorption modulator. A directly- modulated dual-section laser can provide improved modulation performance under a low bias level ( i.e., below the threshold level) compared with a standard directly-modulated laser. By combining the extinction ratio from a dual-section laser with that from an electro-absorption modulator section, a total extinction ratio of 49.6. dB are successfully achieved.

Divisible ℤ-modules

Directory of Open Access Journals (Sweden)

Futa Yuichi

2016-03-01

Full Text Available In this article, we formalize the definition of divisible ℤ-module and its properties in the Mizar system [3]. We formally prove that any non-trivial divisible ℤ-modules are not finitely-generated.We introduce a divisible ℤ-module, equivalent to a vector space of a torsion-free ℤ-module with a coefficient ring ℚ. ℤ-modules are important for lattice problems, LLL (Lenstra, Lenstra and Lovász base reduction algorithm [15], cryptographic systems with lattices [16] and coding theory [8].

Regulating the ethylene response of a plant by modulation of F-box proteins

Science.gov (United States)

Guo, Hongwei [Beijing, CN; Ecker, Joseph R [Carlsbad, CA

2014-01-07

The relationship between F-box proteins and proteins invovled in the ethylene response in plants is described. In particular, F-box proteins may bind to proteins involved in the ethylene response and target them for degradation by the ubiquitin/proteasome pathway. The transcription factor EIN3 is a key transcription factor mediating ethylne-regulated gene expression and morphological responses. EIN3 is degraded through a ubiquitin/proteasome pathway mediated by F-box proteins EBF1 and EBF2. The link between F-box proteins and the ethylene response is a key step in modulating or regulating the response of a plant to ethylene. Described herein are transgenic plants having an altered sensitivity to ethylene, and methods for making transgenic plant haing an althered sensitivity to ethylene by modulating the level of activity of F-box proteins. Methods of altering the ethylene response in a plant by modulating the activity or expression of an F-box protein are described. Also described are methods of identifying compounds that modulate the ethylene response in plants by modulating the level of F-box protein expression or activity.

Selective spatial attention modulates bottom-up informational masking of speech.

Science.gov (United States)

Carlile, Simon; Corkhill, Caitlin

2015-03-02

To hear out a conversation against other talkers listeners overcome energetic and informational masking. Largely attributed to top-down processes, information masking has also been demonstrated using unintelligible speech and amplitude-modulated maskers suggesting bottom-up processes. We examined the role of speech-like amplitude modulations in information masking using a spatial masking release paradigm. Separating a target talker from two masker talkers produced a 20 dB improvement in speech reception threshold; 40% of which was attributed to a release from informational masking. When across frequency temporal modulations in the masker talkers are decorrelated the speech is unintelligible, although the within frequency modulation characteristics remains identical. Used as a masker as above, the information masking accounted for 37% of the spatial unmasking seen with this masker. This unintelligible and highly differentiable masker is unlikely to involve top-down processes. These data provides strong evidence of bottom-up masking involving speech-like, within-frequency modulations and that this, presumably low level process, can be modulated by selective spatial attention.

Estimating the Effects of Module Area on Thin-Film Photovoltaic System Costs: Preprint

Energy Technology Data Exchange (ETDEWEB)

Horowitz, Kelsey A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Fu, Ran [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Silverman, Timothy J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Woodhouse, Michael A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sun, Xingshu [Purdue University; Alam, Muhammad A [Purdue University

2018-03-29

We investigate the potential effects of module area on the cost and performance of photovoltaic systems. Applying a bottom-up methodology, we analyzed the costs associated with thin-film modules and systems as a function of module area. We calculate a potential for savings of up to 0.10 dollars/W and 0.13 dollars/W in module manufacturing costs for CdTe and CIGS respectively, with large area modules. We also find that an additional 0.04 dollars/W savings in balance-of-systems costs may be achieved. Sensitivity of the dollar/W cost savings to module efficiency, manufacturing yield, and other parameters is presented. Lifetime energy yield must also be maintained to realize reductions in the levelized cost of energy; the effects of module size on energy yield for monolithic thin-film modules are not yet well understood. Finally, we discuss possible non-cost barriers to adoption of large area modules.

Amplitude modulation detection with concurrent frequency modulation.

Science.gov (United States)

Nagaraj, Naveen K

2016-09-01

Human speech consists of concomitant temporal modulations in amplitude and frequency that are crucial for speech perception. In this study, amplitude modulation (AM) detection thresholds were measured for 550 and 5000 Hz carriers with and without concurrent frequency modulation (FM), at AM rates crucial for speech perception. Results indicate that adding 40 Hz FM interferes with AM detection, more so for 5000 Hz carrier and for frequency deviations exceeding the critical bandwidth of the carrier frequency. These findings suggest that future cochlear implant processors, encoding speech fine-structures may consider limiting the FM to narrow bandwidth and to low frequencies.

Examining the time dependence of DAMA's modulation amplitude

Science.gov (United States)

Kelso, Chris; Savage, Christopher; Sandick, Pearl; Freese, Katherine; Gondolo, Paolo

2018-03-01

If dark matter is composed of weakly interacting particles, Earth's orbital motion may induce a small annual variation in the rate at which these particles interact in a terrestrial detector. The DAMA collaboration has identified at a 9.3σ confidence level such an annual modulation in their event rate over two detector iterations, DAMA/NaI and DAMA/LIBRA, each with ˜ 7 years of observations. This data is well fit by a constant modulation amplitude for the two iterations of the experiment. We statistically examine the time dependence of the modulation amplitudes, which "by eye" appear to be decreasing with time in certain energy ranges. We perform a chi-squared goodness of fit test of the average modulation amplitudes measured by the two detector iterations which rejects the hypothesis of a consistent modulation amplitude at greater than 80, 96, and 99.6% for the 2-4, 2-5 and 2-6 keVee energy ranges, respectively. We also find that among the 14 annual cycles there are three ≳ 3σ departures from the average in our estimated data in the 5-6 keVee energy range. In addition, we examined several phenomenological models for the time dependence of the modulation amplitude. Using a maximum likelihood test, we find that descriptions of the modulation amplitude as decreasing with time are preferred over a constant modulation amplitude at anywhere between 1σ and 3σ , depending on the phenomenological model for the time dependence and the signal energy range considered. A time dependent modulation amplitude is not expected for a dark matter signal, at least for dark matter halo morphologies consistent with the DAMA signal. New data from DAMA/LIBRA-phase2 will certainly aid in determining whether any apparent time dependence is a real effect or a statistical fluctuation.

Deficient Rab11 activity underlies glucose hypometabolism in primary neurons of Huntington's disease mice

Energy Technology Data Exchange (ETDEWEB)

Li, Xueyi, E-mail: xli12@partners.org [Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129 (United States); Valencia, Antonio; McClory, Hollis; Sapp, Ellen; Kegel, Kimberly B. [Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129 (United States); DiFiglia, Marian, E-mail: difiglia@helix.mgh.harvard.edu [Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129 (United States)

2012-05-18

Highlights: Black-Right-Pointing-Pointer Primary Huntington's disease neurons are impaired in taking up glucose. Black-Right-Pointing-Pointer Rab11 modulates glucose uptake in neurons. Black-Right-Pointing-Pointer Increasing Rab11 activity attenuates the glucose uptake defect in disease neurons. Black-Right-Pointing-Pointer We provide a novel mechanism for glucose hypometabolism in Huntington's disease. -- Abstract: Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene. Positron emission tomography studies have revealed a decline in glucose metabolism in the brain of patients with HD by a mechanism that has not been established. We examined glucose utilization in embryonic primary cortical neurons of wild-type (WT) and HD knock-in mice, which have 140 CAG repeats inserted in the endogenous mouse huntingtin gene (HD{sup 140Q/140Q}). Primary HD{sup 140Q/140Q} cortical neurons took up significantly less glucose than did WT neurons. Expression of permanently inactive and permanently active forms of Rab11 correspondingly altered glucose uptake in WT neurons, suggesting that normal activity of Rab11 is needed for neuronal uptake of glucose. It is known that Rab11 activity is diminished in HD{sup 140Q/140Q} neurons. Expression of dominant active Rab11 to enhance the activity of Rab11 normalized glucose uptake in HD{sup 140Q/140Q} neurons. These results suggest that deficient activity of Rab11 is a novel mechanism for glucose hypometabolism in HD.

Whole Module Offgas Test Report: Space-Xl Dragon Module

Science.gov (United States)

James, John T.

2012-01-01

On September 26 and September 28,2012 a chemist from the JSC Toxicology Group acquired samples of air in 500 m1 evacuated canisters from the sealed Space-Xl Dragon Module. One sample was also acquired from Space-X Facility near the module at the start of the test. Samples of the module air were taken in triplicate once the module had been sealed, and then taken again in triplicate 1.98 days later. Ofthe triplicate samples, the first served as a line purge, and the last two were analyzed. The results of 5 samples are reported.

Activation of the human complement system by cholesterol-rich and pegylated liposomes - Modulation of cholesterol-rich liposome-mediated complement activation by elevated serum LDL and HDL levels

DEFF Research Database (Denmark)

Moghimi, S.M.; Hamad, I.; Bunger, R.

2006-01-01

level of S-protein-bound form of the terminal complex (SC5b-9). However, liposome-induced rise of SC5b-9 was significantly suppressed when serum HDL cholesterol levels increased by 30%. Increase of serum LDL to levels similar to that observed in heterozygous familial hypercholesterolemia also suppressed......Intravenously infused liposomes may induce cardiopulmonary distress in some human subjects, which is a manifestation of "complement activation-related pseudoallergy." We have now examined liposome-mediated complement activation in human sera with elevated lipoprotein (LDL and HDL) levels, since...... abnormal or racial differences in serum lipid profiles seem to modulate the extent of complement activation and associated adverse responses. In accordance with our earlier observations, cholesterol-rich (45 mol% cholesterol) liposomes activated human complement, as reflected by a significant rise in serum...

Time Reversal UWB Communication System: A Novel Modulation Scheme with Experimental Validation

Directory of Open Access Journals (Sweden)

Khaleghi A

2010-01-01

Full Text Available A new modulation scheme is proposed for a time reversal (TR ultra wide-band (UWB communication system. The new modulation scheme uses the binary pulse amplitude modulation (BPAM and adds a new level of modulation to increase the data rate of a TR UWB communication system. Multiple data bits can be transmitted simultaneously with a cost of little added interference. Bit error rate (BER performance and the maximum achievable data rate of the new modulation scheme are theoretically analyzed. Two separate measurement campaigns are carried out to analyze the proposed modulation scheme. In the first campaign, the frequency responses of a typical indoor channel are measured and the performance is studied by the simulations using the measured frequency responses. Theoretical and the simulative performances are in strong agreement with each other. Furthermore, the BER performance of the proposed modulation scheme is compared with the performance of existing modulation schemes. It is shown that the proposed modulation scheme outperforms QAM and PAM for in an AWGN channel. In the second campaign, an experimental validation of the proposed modulation scheme is done. It is shown that the performances with the two measurement campaigns are in good agreement.

Electrically induced contraction levels of the quadriceps femoris muscles in healthy men: the effects of three patterns of burst-modulated alternating current and volitional muscle fatigue.

Science.gov (United States)

Parker, Michael G; Broughton, Alex J; Larsen, Ben R; Dinius, Josh W; Cimbura, Mac J; Davis, Matthew

2011-12-01

The purpose of this study was to compare electrically induced contraction levels produced by three patterns of alternating current in fatigued and nonfatigued skeletal muscles. Eighteen male volunteers without health conditions, with a mean (SD) age of 24.9 (3.4) yrs were randomly exposed to a fatiguing volitional isometric quadriceps contraction and one of three patterns of 2.5-KHz alternating current; two were modulated at 50 bursts per second (10% burst duty cycle with five cycles per burst and 90% burst duty cycle with 45 cycles per burst), and one pattern was modulated at 100 bursts per second (10% burst duty cycle with 2.5 cycles per burst). The electrically induced contraction levels produced by the three patterns of electrical stimulation were compared before and after the fatiguing contraction. The 10% burst duty cycles produced 42.9% (95% confidence interval, 29.1%-56.7%) and 32.1% (95% confidence interval, 18.2%-45.9%) more muscle force (P stronger muscle contractions. Furthermore, the stimulation patterns had no influence on the difference in muscle force before and after the fatiguing quadriceps contraction. Consequently, for clinical applications in which high forces are desired, the patterns using the 10% burst duty cycle may be helpful.

Model Development of Degradation of PV Modules Backsheet with Locating Place of Module

Energy Technology Data Exchange (ETDEWEB)

Kempe, Michael D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wang, Yu [Case Western Reserve University; Fairbrother, Andrew [National Institute of Standards and Technology (NIST); Merzlic, Sebastien [Arkema; Julien, Scott [Northeastern University; Fridman, Lucas S. [Case Western Reserve University; Loyer, Camille [Arkema; Lefebvre, Amy L. [Arkema; O' Brien, Gregory [Arkema; Gu, Xiaohong [National Institute of Standards and Technology (NIST); Ji, Liang [Underwriters Laboratories; Boyce, Kenneth P. [Underwriters Laboratories; Wan, Kai-tak [Northeastern University; French, Roger H. [Case Western Reserve University; Bruckman, Laura S. [Case Western Reserve University

2017-08-23

Performance of a photovoltaic (PV) module is related to the micro-environment around the module. The position of photovoltaic modules in an array row have a large effect on the yellowing and gloss of PV module backsheet exposed in Dfa climatic zone (Gaithersburg, MD) with a polyethylene naphthalate (PEN) outer layer. Stress/Response models of yellowing and gloss-losing as function of location parameters of module, including the shed, row, measurement position in a same module and the distance of module location to the row center, are under development. The module installation height had the greatest influence on degradation of PEN PV backsheet in the Dfa climatic zone. The module backsheets at the end of an array have higher degradation rate (edge effect). The edge effect decreases with increasing of module installation heights.

Modulation masking produced by second-order modulators

DEFF Research Database (Denmark)

Füllgrabe, Christian; Moore, Brian C.J.; Demany, Laurent

2005-01-01

Recent studies suggest that an auditory nonlinearity converts second-order sinusoidal amplitude modulation (SAM) (i.e., modulation of SAM depth) into a first-order SAM component, which contributes to the perception of second-order SAM. However, conversion may also occur in other ways such as coch...

An integrative approach to inferring biologically meaningful gene modules

Directory of Open Access Journals (Sweden)

Wang Kai

2011-07-01

Full Text Available Abstract Background The ability to construct biologically meaningful gene networks and modules is critical for contemporary systems biology. Though recent studies have demonstrated the power of using gene modules to shed light on the functioning of complex biological systems, most modules in these networks have shown little association with meaningful biological function. We have devised a method which directly incorporates gene ontology (GO annotation in construction of gene modules in order to gain better functional association. Results We have devised a method, Semantic Similarity-Integrated approach for Modularization (SSIM that integrates various gene-gene pairwise similarity values, including information obtained from gene expression, protein-protein interactions and GO annotations, in the construction of modules using affinity propagation clustering. We demonstrated the performance of the proposed method using data from two complex biological responses: 1. the osmotic shock response in Saccharomyces cerevisiae, and 2. the prion-induced pathogenic mouse model. In comparison with two previously reported algorithms, modules identified by SSIM showed significantly stronger association with biological functions. Conclusions The incorporation of semantic similarity based on GO annotation with gene expression and protein-protein interaction data can greatly enhance the functional relevance of inferred gene modules. In addition, the SSIM approach can also reveal the hierarchical structure of gene modules to gain a broader functional view of the biological system. Hence, the proposed method can facilitate comprehensive and in-depth analysis of high throughput experimental data at the gene network level.

High power n-type metal-wrap-through cells and modules using industrial processes

Energy Technology Data Exchange (ETDEWEB)

Guillevin, N.; Heurtault, B.J.B.; Geerligs, L.J.; Van Aken, B.B.; Bennett, I.J.; Jansen, M.J.; Weeber, A.W.; Bultman, J.H. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Jianming, Wang; Ziqian, Wang; Jinye, Zhai; Zhiliang, Wan; Shuquan, Tian; Wenchao, Zhao; Zhiyan, Hu; Gaofei, Li; Bo, Yu; Jingfeng, Xiong [Yingli Green Energy Holding Co.,Ltd. 3399 North Chaoyang Avenue, Baoding (China)

2013-10-15

This paper reviews our recent progress in the development of metal wrap through (MWT) cells and modules, produced from n-type Czochralski silicon wafers. The use of n-type silicon as base material allows for high efficiencies: for front emitter-contacted industrial cells, efficiencies above 20% have been reported. N-type MWT (nMWT) cells produced by industrial process technologies allow even higher efficiency due to reduced front metal coverage. Based on the same industrial technology, the efficiency of the bifacial n-MWT cells exceeds the efficiency of the n-type front-and-rear contact and bifacial 'Pasha' technology (n-Pasha) by 0.1-0.2% absolute, with a maximum nMWT efficiency of 20.1% so far. Additionally, full back-contacting of the MWT cells in a module results in reduced cell to module (CTM) fill factor losses. In a direct 60-cell module performance comparison, the n-MWT module, based on integrated backfoil, produced 3% higher power output than the comparable tabbed front emitter-contacted n-Pasha module. Thanks to reduced resistive losses in copper circuitry on the backfoil compared to traditional tabs, the CTM FF loss of the MWT module was reduced by about 2.2%abs. compared to the tabbed front emitter contact module. A full-size module made using MWT cells of 19.6% average efficiency resulted in a power output close to 280W. Latest results of the development of the n-MWT technology at cell and module level are discussed in this paper, including a recent direct comparison run between n-MWT and n-Pasha cells and results of n-MWT cells from 140{mu}m thin mono-crystalline wafers, with only very slight loss (1% of Isc) for the thin cells. Also reverse characteristics and effects of reverse bias for extended time at cell and module level are reported, where we find a higher tolerance of MWT modules than tabbed front contact modules for hotspots.

Differential Aging Trajectories of Modulation of Activation to Cognitive Challenge in APOE ε4 Groups: Reduced Modulation Predicts Poorer Cognitive Performance.

Science.gov (United States)

Foster, Chris M; Kennedy, Kristen M; Rodrigue, Karen M

2017-07-19

The present study was designed to investigate the effect of a genetic risk factor for Alzheimer's disease (AD), ApolipoproteinE ε4 (APOEε4), on the ability of the brain to modulate activation in response to cognitive challenge in a lifespan sample of healthy human adults. A community-based sample of 181 cognitively intact, healthy adults were recruited from the Dallas-Fort Worth metroplex. Thirty-one APOEε4+ individuals (48% women), derived from the parent sample, were matched based on sex, age, and years of education to 31 individuals who were APOEε4-negative (APOEε4-). Ages ranged from 20 to 86 years of age. Blood oxygen level-dependent functional magnetic resonance imaging was collected during the performance of a visuospatial distance judgment task with three parametric levels of difficulty. Multiple regression was used in a whole-brain analysis with age, APOE group, and their interaction predicting functional brain modulation in response to difficulty. Results revealed an interaction between age and APOE in a large cluster localized primarily to the bilateral precuneus. APOEε4- individuals exhibited age-invariant modulation in response to task difficulty, whereas APOEε4+ individuals showed age-related reduction of modulation in response to increasing task difficulty compared with ε4- individuals. Decreased modulation in response to cognitive challenge was associated with reduced task accuracy as well as poorer name-face associative memory performance. Findings suggest that APOEε4 is associated with a reduction in the ability of the brain to dynamically modulate in response to cognitive challenge. Coupled with a significant genetic risk factor for AD, changes in modulation may provide additional information toward identifying individuals potentially at risk for cognitive decline associated with preclinical AD. SIGNIFICANCE STATEMENT Understanding how risk factors for Alzheimer's disease (AD) affect brain function and cognition in healthy adult samples

Young module multiplicities and classifying the indecomposable Young permutation modules

OpenAIRE

Gill, Christopher C.

2012-01-01

We study the multiplicities of Young modules as direct summands of permutation modules on cosets of Young subgroups. Such multiplicities have become known as the p-Kostka numbers. We classify the indecomposable Young permutation modules, and, applying the Brauer construction for p-permutation modules, we give some new reductions for p-Kostka numbers. In particular we prove that p-Kostka numbers are preserved under multiplying partitions by p, and strengthen a known reduction given by Henke, c...

Spectrotemporal Modulation Detection and Speech Perception by Cochlear Implant Users.

Science.gov (United States)

Won, Jong Ho; Moon, Il Joon; Jin, Sunhwa; Park, Heesung; Woo, Jihwan; Cho, Yang-Sun; Chung, Won-Ho; Hong, Sung Hwa

2015-01-01

Spectrotemporal modulation (STM) detection performance was examined for cochlear implant (CI) users. The test involved discriminating between an unmodulated steady noise and a modulated stimulus. The modulated stimulus presents frequency modulation patterns that change in frequency over time. In order to examine STM detection performance for different modulation conditions, two different temporal modulation rates (5 and 10 Hz) and three different spectral modulation densities (0.5, 1.0, and 2.0 cycles/octave) were employed, producing a total 6 different STM stimulus conditions. In order to explore how electric hearing constrains STM sensitivity for CI users differently from acoustic hearing, normal-hearing (NH) and hearing-impaired (HI) listeners were also tested on the same tasks. STM detection performance was best in NH subjects, followed by HI subjects. On average, CI subjects showed poorest performance, but some CI subjects showed high levels of STM detection performance that was comparable to acoustic hearing. Significant correlations were found between STM detection performance and speech identification performance in quiet and in noise. In order to understand the relative contribution of spectral and temporal modulation cues to speech perception abilities for CI users, spectral and temporal modulation detection was performed separately and related to STM detection and speech perception performance. The results suggest that that slow spectral modulation rather than slow temporal modulation may be important for determining speech perception capabilities for CI users. Lastly, test-retest reliability for STM detection was good with no learning. The present study demonstrates that STM detection may be a useful tool to evaluate the ability of CI sound processing strategies to deliver clinically pertinent acoustic modulation information.

Hierarchical surface code for network quantum computing with modules of arbitrary size

Science.gov (United States)

Li, Ying; Benjamin, Simon C.

2016-10-01

The network paradigm for quantum computing involves interconnecting many modules to form a scalable machine. Typically it is assumed that the links between modules are prone to noise while operations within modules have a significantly higher fidelity. To optimize fault tolerance in such architectures we introduce a hierarchical generalization of the surface code: a small "patch" of the code exists within each module and constitutes a single effective qubit of the logic-level surface code. Errors primarily occur in a two-dimensional subspace, i.e., patch perimeters extruded over time, and the resulting noise threshold for intermodule links can exceed ˜10 % even in the absence of purification. Increasing the number of qubits within each module decreases the number of qubits necessary for encoding a logical qubit. But this advantage is relatively modest, and broadly speaking, a "fine-grained" network of small modules containing only about eight qubits is competitive in total qubit count versus a "course" network with modules containing many hundreds of qubits.

Percutaneous epidural neurostimulation in modulation of paraplegic spasticity. Six case reports.

Science.gov (United States)

Richardson, R R; Cerullo, L J; McLone, D G; Gutierrez, F A; Lewis, V

1979-01-01

Six cases of paraplegic, post-traumatic spasticity, alleviated by percutaneous epidural neurostimulation with temporary or permanent implanted neuroelectrodes from the L1 to L4 intervertebral levels are presented. Modulation of this spasticity and secondary beneficial physiological effects were achieved, including regulation of bowel regimens, production of sweating and piloerection below the level of the lesion, and morning erections. The main advantages of percutaneous epidural neurostimulation in modulating spasticity are the avoidance of destructive neurosurgical procedures, the regulation of secondary physiological and autonomic responses, the avoidance of antispasticity medications, and the reversibility of the neurostimulation procedure.

Phase ramping and modulation of reflectometer signals

International Nuclear Information System (INIS)

Conway, G.; Bartlett, D.; Stott, P.

1999-06-01

The phase and amplitude signals of JET heterodyne reflectometers show varying levels of high frequency turbulence superimposed on a slow changing mean. The phase signal also shows multi-radian (>1 fringe) variations with two quite different time scales (2-10ms and sub-ms). In both cases the mean reflected power, together with turbulent phase and amplitude fluctuation levels, are modulated synchronously with the phase fringes. The slow fringes appear to result from radial movement of the cutoff layer with the amplitude modulation possibly due to multiple reflection between plasma and wall. The fast fringes occur in intermittent bursts and appear to be phase runaway resulting from antenna misalignment. Using a 2D physical optics simulation code it is possible to replicate the fast bursts of phase runaway from steady-state turbulence and misaligned antennas. This offers a possible alternative explanation for some of the observations of bursting turbulence seen in reflectometer signals. (author)

Electro-optic modulator with ultra-low residual amplitude modulation for frequency modulation and laser stabilization.

Science.gov (United States)

Tai, Zhaoyang; Yan, Lulu; Zhang, Yanyan; Zhang, Xiaofei; Guo, Wenge; Zhang, Shougang; Jiang, Haifeng

2016-12-01

The reduction of the residual amplitude modulation (RAM) induced by electro-optic modulation is essential for many applications of frequency modulation spectroscopy requiring a lower system noise floor. Here, we demonstrate a simple passive approach employing an electro-optic modulator (EOM) cut at Brewster's angle. The proposed EOM exhibits a RAM of a few parts per million, which is comparable with that achieved by a common EOM under critical active temperature and bias voltage controls. The frequency instability of a 10 cm cavity-stabilized laser induced by the RAM effect of the proposed EOM is below 3×10-17 for integration times from 1 to 1000 s, and below 4×10-16 for comprehensive noise contributions for integration times from 1 to 100 s.

Reconstruction of gene regulatory modules from RNA silencing of IFN-α modulators: experimental set-up and inference method.

Science.gov (United States)

Grassi, Angela; Di Camillo, Barbara; Ciccarese, Francesco; Agnusdei, Valentina; Zanovello, Paola; Amadori, Alberto; Finesso, Lorenzo; Indraccolo, Stefano; Toffolo, Gianna Maria

2016-03-12

Inference of gene regulation from expression data may help to unravel regulatory mechanisms involved in complex diseases or in the action of specific drugs. A challenging task for many researchers working in the field of systems biology is to build up an experiment with a limited budget and produce a dataset suitable to reconstruct putative regulatory modules worth of biological validation. Here, we focus on small-scale gene expression screens and we introduce a novel experimental set-up and a customized method of analysis to make inference on regulatory modules starting from genetic perturbation data, e.g. knockdown and overexpression data. To illustrate the utility of our strategy, it was applied to produce and analyze a dataset of quantitative real-time RT-PCR data, in which interferon-α (IFN-α) transcriptional response in endothelial cells is investigated by RNA silencing of two candidate IFN-α modulators, STAT1 and IFIH1. A putative regulatory module was reconstructed by our method, revealing an intriguing feed-forward loop, in which STAT1 regulates IFIH1 and they both negatively regulate IFNAR1. STAT1 regulation on IFNAR1 was object of experimental validation at the protein level. Detailed description of the experimental set-up and of the analysis procedure is reported, with the intent to be of inspiration for other scientists who want to realize similar experiments to reconstruct gene regulatory modules starting from perturbations of possible regulators. Application of our approach to the study of IFN-α transcriptional response modulators in endothelial cells has led to many interesting novel findings and new biological hypotheses worth of validation.

A two-level voltage source inverter with differentially sinusoidal pulse width modulation used in the interconnection system of a wind turbine generator

Directory of Open Access Journals (Sweden)

Alexandros C. Charalampidis

2014-10-01

Full Text Available This study analyses an interconnection system based on differentially sinusoidal pulse width modulation, used for the interconnection to the grid of a variable speed wind turbine. The modulation technique used provides specific advantages in comparison with the commonly used sinusoidal pulse width modulation (SPWM technique, such as lower DC bus voltage requirements, smaller switching losses for the same switching frequency as well as less higher harmonic content in the voltage waveforms produced. The respective control system is also described in detail. Thus this study provides a guide enabling the design of any interconnection system based on this modulation technique.

Significantly High Modulation Efficiency of Compact Graphene Modulator Based on Silicon Waveguide.

Science.gov (United States)

Shu, Haowen; Su, Zhaotang; Huang, Le; Wu, Zhennan; Wang, Xingjun; Zhang, Zhiyong; Zhou, Zhiping

2018-01-17

We theoretically and experimentally demonstrate a significantly large modulation efficiency of a compact graphene modulator based on a silicon waveguide using the electro refractive effect of graphene. The modulation modes of electro-absorption and electro-refractive can be switched with different applied voltages. A high extinction ratio of 25 dB is achieved in the electro-absorption modulation mode with a driving voltage range of 0 V to 1 V. For electro-refractive modulation, the driving voltage ranges from 1 V to 3 V with a 185-pm spectrum shift. The modulation efficiency of 1.29 V · mm with a 40-μm interaction length is two orders of magnitude higher than that of the first reported graphene phase modulator. The realisation of phase and intensity modulation with graphene based on a silicon waveguide heralds its potential application in optical communication and optical interconnection systems.

Major enhancement of extra-low-frequency radiation by increasing the high-frequency heating wave power in electrojet modulation

International Nuclear Information System (INIS)

Kuo, S.P.; Lee, S.H.; Kossey, Paul

2002-01-01

Extra-low-frequency (ELF) wave generation by modulated polar electrojet currents is studied. The amplitude-modulated high-frequency (HF) heating wave excites a stimulated thermal instability to enhance the electrojet current modulation by the passive Ohmic heating process. Inelastic collisions of electrons with neutral particles (mainly due to vibrational excitation of N 2 ) damp nonlinearly this instability, which is normally saturated at low levels. However, the electron's inelastic collision loss rate drops rapidly to a low value in the energy regime from 3.5 to 6 eV. As the power of the modulated HF heating wave exceeds a threshold level, it is shown that significant electron heating enhanced by the stimulated thermal instability can indeed cause a steep drop in the electron inelastic collision loss rate. Consequently, this instability saturates at a much higher level, resulting to a near step increase (of about 10-13 dB, depending on the modulation wave form) in the spectral intensity of ELF radiation. The dependence of the threshold power of the HF heating wave on the modulation frequency is determined

A high precision radiation-tolerant LVDT conditioning module

Energy Technology Data Exchange (ETDEWEB)

Masi, A. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Danzeca, S. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); IES, F-34000 Montpellier (France); Losito, R.; Peronnard, P. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Secondo, R., E-mail: raffaello.secondo@cern.ch [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Spiezia, G. [EN/STI Group, CERN - European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland)

2014-05-01

Linear variable differential transformer (LVDT) position sensors are widely used in particle accelerators and nuclear plants, thanks to their properties of contact-less sensing, radiation tolerance, infinite resolution, good linearity and cost efficiency. Many applications require high reading accuracy, even in environments with high radiation levels, where the conditioning electronics must be located several hundred meters away from the sensor. Sometimes even at long distances the conditioning module is still exposed to ionizing radiation. Standard off-the-shelf electronic conditioning modules offer limited performances in terms of reading accuracy and long term stability already with short cables. A radiation tolerant stand-alone LVDT conditioning module has been developed using Commercial Off-The-Shelf (COTS) components. The reading of the sensor output voltages is based on a sine-fit algorithm digitally implemented on an FPGA ensuring few micrometers reading accuracy even with low signal-to-noise ratios. The algorithm validation and board architecture are described. A full metrological characterization of the module is reported and radiation tests results are discussed.

Design Elements and Electrical Performance of a Bifacial BIPV Module

Directory of Open Access Journals (Sweden)

Jun-Gu Kang

2016-01-01

Full Text Available Bifacial BIPV systems have great potential when applied to buildings given their use of a glass-to-glass structure. However, the performance of bifacial solar cells depends on a variety of design factors. Therefore, in order to apply bifacial solar cells to buildings, a bifacial PV module performance analysis should be carried out, including consideration of the various design elements and reflecting a wide range of installation conditions. This study focuses on the performance of a bifacial BIPV module applied to a building envelope. The results here show that the design elements of reflectivity and the transparent space ratio have the greatest impact on performance levels. The distance between the module and the wall had less of an impact on performance. The bifacial BIPV module produced output up to 30% greater than the output of monofacial PV modules, depending on the design elements. Bifacial BIPV modules themselves should have transparent space ratios of at least 30%. When a dark color is used on the external wall with reflectivity of 50% or less, bifacial BIPV modules with transparent space ratios of 40% and above should be used. In order to achieve higher performance through the installation of bifacial BIPV modules, design conditions which facilitate reflectivity exceeding 50% and a transparent space ratio which exceeds 30% must be met.

The Orphan G Protein-coupled Receptor Gpr175 (Tpra40) Enhances Hedgehog Signaling by Modulating cAMP Levels.

Science.gov (United States)

Singh, Jaskirat; Wen, Xiaohui; Scales, Suzie J

2015-12-04

The Hedgehog (Hh) signaling pathway plays an essential role in vertebrate embryonic tissue patterning of many developing organs. Signaling occurs predominantly in primary cilia and is initiated by the entry of the G protein-coupled receptor (GPCR)-like protein Smoothened into cilia and culminates in gene transcription via the Gli family of transcription factors upon their nuclear entry. Here we identify an orphan GPCR, Gpr175 (also known as Tpra1 or Tpra40: transmembrane protein, adipocyte associated 1 or of 40 kDa), which also localizes to primary cilia upon Hh stimulation and positively regulates Hh signaling. Interaction experiments place Gpr175 at the level of PKA and upstream of the Gαi component of heterotrimeric G proteins, which itself localizes to cilia and can modulate Hh signaling. Gpr175 or Gαi1 depletion leads to increases in cellular cAMP levels and in Gli3 processing into its repressor form. Thus we propose that Gpr175 coupled to Gαi1 normally functions to inhibit the production of cAMP by adenylyl cyclase upon Hh stimulation, thus maximizing signaling by turning off PKA activity and hence Gli3 repressor formation. Taken together our data suggest that Gpr175 is a novel positive regulator of the Hh signaling pathway. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Neutron-transparent first wall for module testing

International Nuclear Information System (INIS)

Fuller, G.M.; Cramer, B.A.; Haines, J.R.; Kirchner, J.; Engholm, B.A.; Seki, M.

1983-01-01

Major design goals for FED-R are the achievement of: (1) a high level of neutron exposure of the test modules and (2) a capability for rapid changeout of test modules. A major factor in rapid changeout is perceived to be the location of the vacuum boundary. In FED-R this boundary was set at the first wall so that module changeout did not require the plasma chamber to be brought up to atmosphere. Efforts to realize these goals in the design resulted in a neutronically thin outboard wall for the vacuum vessel constructed of 316 stainless steel (SS) with helium as a coolant. A normalized 14-MeV neutron transmission of 0.82 is expected, with an inlet pressure of 2 MPa and a pumping power requirement of 8.7 MW. Other options considered in the study were aluminum as a wall material and water and sodium potassium (NaK) as coolants

WRAP Module 1 waste characterization plan

International Nuclear Information System (INIS)

Mayancsik, B.A.

1995-01-01

The purpose of this document is to present the characterization methodology for waste generated, processed, or otherwise the responsibility of the Waste Receiving and Processing (WRAP) Module 1 facility. The scope of this document includes all solid low level waste (LLW), transuranic (TRU), mixed waste (MW), and dangerous waste. This document is not meant to be all-inclusive of the waste processed or generated within WRAP Module 1, but to present a methodology for characterization. As other streams are identified, the method of characterization will be consistent with the other streams identified in this plan. The WRAP Module 1 facility is located in the 200 West Area of the Hanford Site. The facility's function is two-fold. The first is to verify/characterize, treat and repackage contact handled (CH) waste currently in retrievable storage in the LLW Burial Grounds, Hanford Central Waste Complex, and the Transuranic Storage and Assay Facility (TRUSAF). The second is to verify newly generated CH TRU waste and LLW, including MW. The WRAP Module 1 facility provides NDE and NDA of the waste for both drums and boxes. The NDE is used to identify the physical contents of the waste containers to support waste characterization and processing, verification, or certification. The NDA results determine the radioactive content and distribution of the waste

Social, state-dependent and environmental modulation of faecal corticosteroid levels in free-ranging female spotted hyenas.

Science.gov (United States)

Goymann, W; East, M L; Wachter, B; Höner, O P; Möstl, E; Van't Hof, T J; Hofer, H

2001-12-07

Little is known about to what extent the sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis may be state dependent and vary in the same species between environments. Here we tested whether the faecal corticosteroid concentrations of matrilineal adult female spotted hyenas are influenced by social and reproductive status in adjacent ecosystems and whether they vary between periods with and without social stress. Females in the Serengeti National Park frequently become socially subordinate intruders in other hyena territories by undertaking long-distance foraging trips to migratory herds, whereas in the Ngorongoro Crater they usually forage inside their own small territories on resident prey. The faecal corticosteroid concentrations in Serengeti females were significantly higher than in Ngorongoro females. Energy expenditure by lactation is exceptionally high in spotted hyenas and this may be reflected in their corticosteroid levels. The faecal corticosteroid levels in both populations were higher in lactating than in non-lactating females. During periods of social stability, faecal corticosteroid concentrations increased in non-lactating females but not in lactating females as social status declined. Lactating Serengeti females had significantly higher faecal corticosteroid concentrations during periods with acute severe social stress than during periods without, indicating that the HPA axis is sensitive to social stimuli even in lactating females. So far few studies have used non-invasive monitoring methods for assessing social stress in freeranging animals. This study demonstrates for the first time, to the authors' knowledge, that corticosteroid concentrations may differ between periods with and without social stress for a free-ranging female mammal and that the modulating effect of social status may depend on reproductive status.

Periodically modulated single-photon transport in one-dimensional waveguide

Science.gov (United States)

Li, Xingmin; Wei, L. F.

2018-03-01

Single-photon transport along a one-dimension waveguide interacting with a quantum system (e.g., two-level atom) is a very useful and meaningful simplified model of the waveguide-based optical quantum devices. Thus, how to modulate the transport of the photons in the waveguide structures by adjusting certain external parameters should be particularly important. In this paper, we discuss how such a modulation could be implemented by periodically driving the energy splitting of the interacting atom and the atom-photon coupling strength. By generalizing the well developed time-independent full quantum mechanical theory in real space to the time-dependent one, we show that various sideband-transmission phenomena could be observed. This means that, with these modulations the photon has certain probabilities to transmit through the scattering atom in the other energy sidebands. Inversely, by controlling the sideband transmission the periodic modulations of the single photon waveguide devices could be designed for the future optical quantum information processing applications.

Weakly Coretractable Modules

Science.gov (United States)

Hadi, Inaam M. A.; Al-aeashi, Shukur N.

2018-05-01

If R is a ring with identity and M is a unitary right R-module. Here we introduce the class of weakly coretractable module. Some basic properties are investigated and some relationships between these modules and other related one are introduced.

Optimised dispersion management and modulation formats for high speed optical communication systems

DEFF Research Database (Denmark)

Tokle, Torger

2004-01-01

both narrow spectral width and good transmission properties. The cost of an optical communication system can be lowered by using longer span lengths to reduce the number of amplifier stations. We experimentally study optimum dispersion compensation schemes for systems with 160 km fibre spans made...... modulated signals. In summary, we show that dispersion management using recently developed fibres in combination with advanced modulation formats significantly improves the transmission performance compared to traditional systems. Multi-level phase modulation is demonstrated at bit rates up to 80 Gbit......This thesis studies dispersion management and modulation formats for optical communication systems using per channel bit rates at and above 10 Gbit/s. Novel modulation formats—including recently proposed multilevel phase modulation—are investigated and demonstrated at bit rates up to 80 Gbit/s. New...

Intensity-modulated arc therapy simplified

International Nuclear Information System (INIS)

Wong, Eugene; Chen, Jeff Z.; Greenland, Jonathan

2002-01-01

Purpose: We present a treatment planning strategy for intensity-modulated radiation therapy using gantry arcs with dynamic multileaf collimator, previously termed intensity-modulated arc therapy (IMAT). Methods and Materials: The planning strategy is an extension of the photon bar arc and asymmetric arc techniques and is classified into three levels of complexity, with increasing number of gantry arcs. This principle allows us to generalize the analysis of the number of arcs required for intensity modulation for a given treatment site. Using a phantom, we illustrate how the current technique is more flexible than the photon bar arc technique. We then compare plans from our strategy with conventional three-dimensional conformal treatment plans for three sites: prostate (prostate plus seminal vesicles), posterior pharyngeal wall, and chest wall. Results: Our strategy generates superior IMAT treatment plans compared to conventional three-dimensional conformal plans. The IMAT plans spare critical organs well, and the trade-off for simplicity is that the dose uniformity in the target volume may not rival that of true inverse treatment plans. Conclusions: The analyses presented in this paper give a better understanding of IMAT plans. Our strategy is easier to understand and more efficient in generating plans than inverse planning systems; our plans are also simpler to modify, and quality assurance is more intuitive

Multi-hit time-to-amplitude CAMAC module (MTAC)

International Nuclear Information System (INIS)

Kang, H.

1980-10-01

A Multi-Hit Time-to-Amplitude Module (MTAC) for the SLAC Mark III drift chamber system has been designed to measure drift time by converting time-proportional chamber signals into analog levels, and converting the analog data by slow readout via a semi-autonomous controller in a CAMAC crate. The single width CAMAC module has 16 wire channels, each with a 4-hit capacity. An externally generated common start initiates an internal precision ramp voltage which is then sampled using a novel shift register gating scheme and CMOS sampling switches. The detailed design and performance specifications are described

Compatibility of copper-electroplated cells with Metal Wrap Through module materials

Energy Technology Data Exchange (ETDEWEB)

Bennett, I.J.; Geerligs, L.J.; Olson, C.L.; Goris, M.J.A.A. [ECN Solar Energy, Petten (Netherlands)

2013-10-16

As part of the European FP7 RandD project 'Cu-PV', the compatibility of copper-electroplated metal wrapthrough (MWT) cells with conductive adhesives has been investigated. The objectives of this project include to reduce, by the use of copper plating, the amount of silver utilized in cell manufacturing, and to demonstrate the compatibility of high-power n-type back-contact module technology with copper-plated cells. The overall goal is to reduce the impact on the environment of cell and module manufacture. MWT module technology as developed by ECN uses conductive adhesive to make the interconnection between cells and a conductive backsheet foil. These adhesives have been proved to result in very reliable modules in the case of cells with fired silver metallization. To determine the compatibility of conductive adhesive with copper-plated cells, component tests were performed, followed by the manufacture of modules with copperplated cells and conductive adhesive interconnections. Climate chamber testing of these modules showed that the adhesive is compatible with the copper-plated cells. The next steps include further optimization of the plating process and additional testing at the module level.

Beta receptor-mediated modulation of the late positive potential in humans.

Science.gov (United States)

de Rover, Mischa; Brown, Stephen B R E; Boot, Nathalie; Hajcak, Greg; van Noorden, Martijn S; van der Wee, Nic J A; Nieuwenhuis, Sander

2012-02-01

Electrophysiological studies have identified a scalp potential, the late positive potential (LPP), which is modulated by the emotional intensity of observed stimuli. Previous work has shown that the LPP reflects the modulation of activity in extrastriate visual cortical structures, but little is known about the source of that modulation. The present study investigated whether beta-adrenergic receptors are involved in the generation of the LPP. We used a genetic individual differences approach (experiment 1) and a pharmacological manipulation (experiment 2) to test the hypothesis that the LPP is modulated by the activation of β-adrenergic receptors. In experiment 1, we found that LPP amplitude depends on allelic variation in the β1-receptor gene polymorphism. In experiment 2, we found that LPP amplitude was modulated by the β-blocker propranolol in a direction dependent on subjects' level of trait anxiety: In participants with lower trait anxiety, propranolol led to a (nonsignificant) decrease in the LPP modulation; in participants with higher trait anxiety, propranolol increased the emotion-related LPP modulation. These results provide initial support for the hypothesis that the LPP reflects the downstream effects, in visual cortical areas, of β-receptor-mediated activation of the amygdala.

Center frequency shift and reduction of feedback in directly modulated external cavity lasers

DEFF Research Database (Denmark)

Schiellerup, G.; Pedersen, Rune Johan Skullerud; Olesen, H.

1989-01-01

It is shown experimentally and theoretically that a center frequency shift occurs when an external cavity laser is directly modulated. The shift can be observed even when the frequency deviation is small compared to the roundtrip frequency of the external cavity and can qualitatively be explained...... by a reduction in the effective feedback level due to modulation. The frequency shift was measured as a function of modulation frequency and current, and frequency shifts up to 350 MHz were observed...

Attentional modulation of auditory steady-state responses.

Science.gov (United States)

Mahajan, Yatin; Davis, Chris; Kim, Jeesun

2014-01-01

Auditory selective attention enables task-relevant auditory events to be enhanced and irrelevant ones suppressed. In the present study we used a frequency tagging paradigm to investigate the effects of attention on auditory steady state responses (ASSR). The ASSR was elicited by simultaneously presenting two different streams of white noise, amplitude modulated at either 16 and 23.5 Hz or 32.5 and 40 Hz. The two different frequencies were presented to each ear and participants were instructed to selectively attend to one ear or the other (confirmed by behavioral evidence). The results revealed that modulation of ASSR by selective attention depended on the modulation frequencies used and whether the activation was contralateral or ipsilateral. Attention enhanced the ASSR for contralateral activation from either ear for 16 Hz and suppressed the ASSR for ipsilateral activation for 16 Hz and 23.5 Hz. For modulation frequencies of 32.5 or 40 Hz attention did not affect the ASSR. We propose that the pattern of enhancement and inhibition may be due to binaural suppressive effects on ipsilateral stimulation and the dominance of contralateral hemisphere during dichotic listening. In addition to the influence of cortical processing asymmetries, these results may also reflect a bias towards inhibitory ipsilateral and excitatory contralateral activation present at the level of inferior colliculus. That the effect of attention was clearest for the lower modulation frequencies suggests that such effects are likely mediated by cortical brain structures or by those in close proximity to cortex.

Brain urea increase is an early Huntington's disease pathogenic event observed in a prodromal transgenic sheep model and HD cases.

Science.gov (United States)

Handley, Renee R; Reid, Suzanne J; Brauning, Rudiger; Maclean, Paul; Mears, Emily R; Fourie, Imche; Patassini, Stefano; Cooper, Garth J S; Rudiger, Skye R; McLaughlan, Clive J; Verma, Paul J; Gusella, James F; MacDonald, Marcy E; Waldvogel, Henry J; Bawden, C Simon; Faull, Richard L M; Snell, Russell G

2017-12-26

The neurodegenerative disorder Huntington's disease (HD) is typically characterized by extensive loss of striatal neurons and the midlife onset of debilitating and progressive chorea, dementia, and psychological disturbance. HD is caused by a CAG repeat expansion in the Huntingtin ( HTT ) gene, translating to an elongated glutamine tract in the huntingtin protein. The pathogenic mechanism resulting in cell dysfunction and death beyond the causative mutation is not well defined. To further delineate the early molecular events in HD, we performed RNA-sequencing (RNA-seq) on striatal tissue from a cohort of 5-y-old OVT73 -line sheep expressing a human CAG-expansion HTT cDNA transgene. Our HD OVT73 sheep are a prodromal model and exhibit minimal pathology and no detectable neuronal loss. We identified significantly increased levels of the urea transporter SLC14A1 in the OVT73 striatum, along with other important osmotic regulators. Further investigation revealed elevated levels of the metabolite urea in the OVT73 striatum and cerebellum, consistent with our recently published observation of increased urea in postmortem human brain from HD cases. Extending that finding, we demonstrate that postmortem human brain urea levels are elevated in a larger cohort of HD cases, including those with low-level neuropathology (Vonsattel grade 0/1). This elevation indicates increased protein catabolism, possibly as an alternate energy source given the generalized metabolic defect in HD. Increased urea and ammonia levels due to dysregulation of the urea cycle are known to cause neurologic impairment. Taken together, our findings indicate that aberrant urea metabolism could be the primary biochemical disruption initiating neuropathogenesis in HD.

Module Testing Techniques for Nuclear Safety Critical Software Using LDRA Testing Tool

International Nuclear Information System (INIS)

Moon, Kwon-Ki; Kim, Do-Yeon; Chang, Hoon-Seon; Chang, Young-Woo; Yun, Jae-Hee; Park, Jee-Duck; Kim, Jae-Hack

2006-01-01

The safety critical software in the I and C systems of nuclear power plants requires high functional integrity and reliability. To achieve those requirement goals, the safety critical software should be verified and tested according to related codes and standards through verification and validation (V and V) activities. The safety critical software testing is performed at various stages during the development of the software, and is generally classified as three major activities: module testing, system integration testing, and system validation testing. Module testing involves the evaluation of module level functions of hardware and software. System integration testing investigates the characteristics of a collection of modules and aims at establishing their correct interactions. System validation testing demonstrates that the complete system satisfies its functional requirements. In order to generate reliable software and reduce high maintenance cost, it is important that software testing is carried out at module level. Module testing for the nuclear safety critical software has rarely been performed by formal and proven testing tools because of its various constraints. LDRA testing tool is a widely used and proven tool set that provides powerful source code testing and analysis facilities for the V and V of general purpose software and safety critical software. Use of the tool set is indispensable where software is required to be reliable and as error-free as possible, and its use brings in substantial time and cost savings, and efficiency

Right hemisphere dominance directly predicts both baseline V1 cortical excitability and the degree of top-down modulation exerted over low-level brain structures.

Science.gov (United States)

Arshad, Q; Siddiqui, S; Ramachandran, S; Goga, U; Bonsu, A; Patel, M; Roberts, R E; Nigmatullina, Y; Malhotra, P; Bronstein, A M

2015-12-17

Right hemisphere dominance for visuo-spatial attention is characteristically observed in most right-handed individuals. This dominance has been attributed to both an anatomically larger right fronto-parietal network and the existence of asymmetric parietal interhemispheric connections. Previously it has been demonstrated that interhemispheric conflict, which induces left hemisphere inhibition, results in the modulation of both (i) the excitability of the early visual cortex (V1) and (ii) the brainstem-mediated vestibular-ocular reflex (VOR) via top-down control mechanisms. However to date, it remains unknown whether the degree of an individual's right hemisphere dominance for visuospatial function can influence, (i) the baseline excitability of the visual cortex and (ii) the extent to which the right hemisphere can exert top-down modulation. We directly tested this by correlating line bisection error (or pseudoneglect), taken as a measure of right hemisphere dominance, with both (i) visual cortical excitability measured using phosphene perception elicited via single-pulse occipital trans-cranial magnetic stimulation (TMS) and (ii) the degree of trans-cranial direct current stimulation (tDCS)-mediated VOR suppression, following left hemisphere inhibition. We found that those individuals with greater right hemisphere dominance had a less excitable early visual cortex at baseline and demonstrated a greater degree of vestibular nystagmus suppression following left hemisphere cathodal tDCS. To conclude, our results provide the first demonstration that individual differences in right hemisphere dominance can directly predict both the baseline excitability of low-level brain structures and the degree of top-down modulation exerted over them. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Attention, working memory, and phenomenal experience of WM content: memory levels determined by different types of top-down modulation

OpenAIRE

Jacob, Jane; Jacobs, Christianne; Silvanto, Juha

2015-01-01

What is the role of top-down attentional modulation in consciously accessing working memory (WM) content? In influential WM models, information can exist in different states, determined by allocation of attention; placing the original memory representation in the center of focused attention gives rise to conscious access. Here we discuss various lines of evidence indicating that such attentional modulation is not sufficient for memory content to be phenomenally experienced. We propose that, i...

a Design of the Driver Airbag Module with Floating Horn Assembly

Science.gov (United States)

Suh, Chang-Min; Lee, Young-Hoon; Suh, Duck-Young

The driver airbag system is designed as a supplemental restraint system in addition to the seatbelt, and is designed to protect the driver's head and chest against severe injury by a device that is actuated in case of vehicle's fronted impact. Deployment of an airbag module with floating horn assembly is a highly dynamic process. The concept of driver airbag module with floating horn assembly and aluminum emblem is presented as a useful parameter when the airbag deploys and the energy is evaluated as performance factor in airbag module. Floating horn assembly is also one of the major factors for driver airbag module design to perform its horn function and check the package between driver airbag module and steering wheel. This study on the design of driver airbag module with floating horn assembly proved the feasibility as a new safety device. However, the system level study is needed for decrease of passenger injury. This study can be used for the implementation of a prototype of DABM with floating horn device.

D-β-hydroxybutyrate is protective in mouse models of Huntington's disease.

Directory of Open Access Journals (Sweden)

Soyeon Lim

Full Text Available Abnormalities in mitochondrial function and epigenetic regulation are thought to be instrumental in Huntington's disease (HD, a fatal genetic disorder caused by an expanded polyglutamine track in the protein huntingtin. Given the lack of effective therapies for HD, we sought to assess the neuroprotective properties of the mitochondrial energizing ketone body, D-β-hydroxybutyrate (DβHB, in the 3-nitropropionic acid (3-NP toxic and the R6/2 genetic model of HD. In mice treated with 3-NP, a complex II inhibitor, infusion of DβHB attenuates motor deficits, striatal lesions, and microgliosis in this model of toxin induced-striatal neurodegeneration. In transgenic R6/2 mice, infusion of DβHB extends life span, attenuates motor deficits, and prevents striatal histone deacetylation. In PC12 cells with inducible expression of mutant huntingtin protein, we further demonstrate that DβHB prevents histone deacetylation via a mechanism independent of its mitochondrial effects and independent of histone deacetylase inhibition. These pre-clinical findings suggest that by simultaneously targeting the mitochondrial and the epigenetic abnormalities associated with mutant huntingtin, DβHB may be a valuable therapeutic agent for HD.

Directed network modules

International Nuclear Information System (INIS)

Palla, Gergely; Farkas, Illes J; Pollner, Peter; Derenyi, Imre; Vicsek, Tamas

2007-01-01

A search technique locating network modules, i.e. internally densely connected groups of nodes in directed networks is introduced by extending the clique percolation method originally proposed for undirected networks. After giving a suitable definition for directed modules we investigate their percolation transition in the Erdos-Renyi graph both analytically and numerically. We also analyse four real-world directed networks, including Google's own web-pages, an email network, a word association graph and the transcriptional regulatory network of the yeast Saccharomyces cerevisiae. The obtained directed modules are validated by additional information available for the nodes. We find that directed modules of real-world graphs inherently overlap and the investigated networks can be classified into two major groups in terms of the overlaps between the modules. Accordingly, in the word-association network and Google's web-pages, overlaps are likely to contain in-hubs, whereas the modules in the email and transcriptional regulatory network tend to overlap via out-hubs

Decoupled Modulation Control

Energy Technology Data Exchange (ETDEWEB)

Wang, Shaobu; Huang, Renke; Huang, Zhenyu; Diao, Ruisheng

2016-06-03

The objective of this research work is to develop decoupled modulation control methods for damping inter-area oscillations with low frequencies, so the damping control can be more effective and easier to design with less interference among different oscillation modes in the power system. A signal-decoupling algorithm was developed that can enable separation of multiple oscillation frequency contents and extraction of a “pure” oscillation frequency mode that are fed into Power System Stabilizers (PSSs) as the modulation input signals. As a result, instead of introducing interferences between different oscillation modes from the traditional approaches, the output of the new PSS modulation control signal mainly affects only one oscillation mode of interest. The new decoupled modulation damping control algorithm has been successfully developed and tested on the standard IEEE 4-machine 2-area test system and a minniWECC system. The results are compared against traditional modulation controls, which demonstrates the validity and effectiveness of the newly-developed decoupled modulation damping control algorithm.

Classes of modules

CERN Document Server

Dauns, John

2006-01-01

Because traditional ring theory places restrictive hypotheses on all submodules of a module, its results apply only to small classes of already well understood examples. Often, modules with infinite Goldie dimension have finite-type dimension, making them amenable to use with type dimension, but not Goldie dimension. By working with natural classes and type submodules (TS), Classes of Modules develops the foundations and tools for the next generation of ring and module theory. It shows how to achieve positive results by placing restrictive hypotheses on a small subset of the complement submodules, Furthermore, it explains the existence of various direct sum decompositions merely as special cases of type direct sum decompositions. Carefully developing the foundations of the subject, the authors begin by providing background on the terminology and introducing the different module classes. The modules classes consist of torsion, torsion-free, s[M], natural, and prenatural. They expand the discussion by exploring...

Thermo-mechanical modelling and experimental validation of CLIC prototype module type 0

CERN Document Server

Kortelainen, Lauri; Koivurova, Hannu; Riddone, Germana; Österberg, Kenneth

Micron level stability of the two-meter repetitive modules constituting the two main linacs is one of the most important requirements to achieve the luminosity goal for the Compact Linear Collider. Structural deformations due to thermal loads and related to the RF power dissipated inside the modules affect the alignment of the linacs and therefore the resulting luminosity performance. A CLIC prototype module has been assembled in a dedicated laboratory and a thermal test program has been started in order to study its thermo-mechanical behaviour. This thesis focuses on the finite elements modelling of the first CLIC prototype module 0. The aim of the modelling is to examine the temperature distributions and the resulting deformations of the module in different operating conditions defined in the thermal test program. The theoretical results have been compared to the experimental ones; the comparison shows that the results are in good agreement both for the thermal behaviour of the module and for the resulting ...

Digital front-end module (DFEM) series; Digital front end module (DFEM) series

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

The digital front-end module (DFEM) is a module in which the processes ranging from the reception of digitally modulated radiofrequencies to the output of digital IF (Intermediate Frequency) signals or data streams are integrated. Beginning with a module for the MCNS (Multimedia Cable Network System) cable modem which was the first module in this business field approved by the Cable Labs, U.S., Toshiba has developed a series of DFEMs for various digital media for satellites, ground waves, and CATV (Cable Television) systems. The series is characterized by (1) the serialization of DFEMs compatible with various digital modulation techniques such as 8 PSK (Phase Shift Keying), OFDM (Orthogonal Frequency Division Multiplexing), and 256 QAM (Quadrature Amplitude Modulation), (2) easy connection with digital circuits thanks to the high shielding effect, and (3) the achievement of smaller size, higher performance, and lower power consumption. (translated by NEDO)

Evaluation of module industrial usage possibility on the making of renography using serial port

International Nuclear Information System (INIS)

Santoso, Wiranto Budi

2003-01-01

The possibilities of using industrial modules on renography with serial port have been investigated. Industrial modules from Advantech company (ADAM 4000 series) have been chosen to be evaluated since they are cheapest among other industrial modules. The Adam 4080 counter modules is used as the pulse counters. This module has two counters so that the counters can be used to count the pulse from two renography detectors separately. Two Adam 4050 digital output modules are used to set the energy window of the Single Channel Analyzer. One module is used to set the energy level while the other one is used to set the delta energy. The investigation is conducted under Windows 98 operating system. For energy window setting the result is good. While for pulse counting, the result of counting depend on other activities working on the windows operating system

Photoabsorption modulation in GaAs: Ga1-xInx as strained-layer superlattices

International Nuclear Information System (INIS)

Sella, I.; Watkins, D.E.; Laurich, B.K.; Smith, D.L.; Subbanna, S.; Kroemer, H.

1990-01-01

Photoabsorption modulation measurements have been made on Ga 1 -x In x As -- GaAs strained-layer superlattices using two approaches: In the first the modulating beam and the test beam have the same wavelength (near the exciton resonance). In the second, the modulation wavelength is much shorter than the test beam wavelength. A dramatic difference is observed in the modulated transmission spectra near the excitonic level for the two modulating wavelengths. The difference in behavior can be explained by screening of the residual surface electric field, which only occurs for the high photon energy modulating beam. This beam excites carriers that are free to drift in the surface field before they are captured in the quantum wells. Carriers excited by the low photon energy modulation beam are created in the wells and can not effectively screen the surface field. We describe a model which explains the nonlinear intensity saturation profile and qualitatively describes the spectral line shape. 4 refs., 4 figs

25 Gbit/s differential phase-shift-keying signal generation using directly modulated quantum-dot semiconductor optical amplifiers

International Nuclear Information System (INIS)

Zeghuzi, A.; Schmeckebier, H.; Stubenrauch, M.; Bimberg, D.; Meuer, C.; Schubert, C.; Bunge, C.-A.

2015-01-01

Error-free generation of 25-Gbit/s differential phase-shift keying (DPSK) signals via direct modulation of InAs quantum-dot (QD) based semiconductor optical amplifiers (SOAs) is experimentally demonstrated with an input power level of −5 dBm. The QD SOAs emit in the 1.3-μm wavelength range and provide a small-signal fiber-to-fiber gain of 8 dB. Furthermore, error-free DPSK modulation is achieved for constant optical input power levels from 3 dBm down to only −11 dBm for a bit rate of 20 Gbit/s. Direct phase modulation of QD SOAs via current changes is thus demonstrated to be much faster than direct gain modulation

Processing and characterization of device solder interconnection and module attachment for power electronics modules

Science.gov (United States)

Haque, Shatil

This research is focused on the processing of an innovative three-dimensional packaging architecture for power electronics building blocks with soldered device interconnections and subsequent characterization of the module's critical interfaces. A low-cost approach termed metal posts interconnected parallel plate structure (MPIPPS) was developed for packaging high-performance modules of power electronics building blocks (PEBB). The new concept implemented direct bonding of copper posts, not wire bonding of fine aluminum wires, to interconnect power devices as well as joining the different circuit planes together. We have demonstrated the feasibility of this packaging approach by constructing PEBB modules (consisting of Insulated Gate Bipolar Transistors (IGBTs), diodes, and a few gate driver elements and passive components). In the 1st phase of module fabrication with IGBTs with Si3N 4 passivation, we had successfully fabricated packaged devices and modules using the MPIPPS technique. These modules were tested electrically and thermally, and they operated at pulse-switch and high power stages up to 6kW. However, in the 2nd phase of module fabrication with polyimide passivated devices, we experienced significant yield problems due to metallization difficulties of these devices. The under-bump metallurgy scheme for the development of a solderable interface involved sputtering of Ti-Ni-Cu and Cr-Cu, and an electroless deposition of Zn-Ni-Au metallization. The metallization process produced excellent yield in the case of Si3N4 passivated devices. However, under the same metallization schemes, devices with a polyimide passivation exhibited inconsistent electrical contact resistance. We found that organic contaminants such as hydrocarbons remain in the form of thin monolayers on the surface, even in the case of as-received devices from the manufacturer. Moreover, in the case of polyimide passivated devices, plasma cleaning introduced a few carbon constituents on the

Relative injectivity and CS-modules

Directory of Open Access Journals (Sweden)

Mahmoud Ahmed Kamal

1994-01-01

Full Text Available In this paper we show that a direct decomposition of modules M⊕N, with N homologically independent to the injective hull of M, is a CS-module if and only if N is injective relative to M and both of M and N are CS-modules. As an application, we prove that a direct sum of a non-singular semisimple module and a quasi-continuous module with zero socle is quasi-continuous. This result is known for quasi-injective modules. But when we confine ourselves to CS-modules we need no conditions on their socles. Then we investigate direct sums of CS-modules which are pairwise relatively inective. We show that every finite direct sum of such modules is a CS-module. This result is known for quasi-continuous modules. For the case of infinite direct sums, one has to add an extra condition. Finally, we briefly discuss modules in which every two direct summands are relatively inective.

Identify Dynamic Network Modules with Temporal and Spatial Constraints

Energy Technology Data Exchange (ETDEWEB)

Jin, R; McCallen, S; Liu, C; Almaas, E; Zhou, X J

2007-09-24

Despite the rapid accumulation of systems-level biological data, understanding the dynamic nature of cellular activity remains a difficult task. The reason is that most biological data are static, or only correspond to snapshots of cellular activity. In this study, we explicitly attempt to detangle the temporal complexity of biological networks by using compilations of time-series gene expression profiling data.We define a dynamic network module to be a set of proteins satisfying two conditions: (1) they form a connected component in the protein-protein interaction (PPI) network; and (2) their expression profiles form certain structures in the temporal domain. We develop the first efficient mining algorithm to discover dynamic modules in a temporal network, as well as frequently occurring dynamic modules across many temporal networks. Using yeast as a model system, we demonstrate that the majority of the identified dynamic modules are functionally homogeneous. Additionally, many of them provide insight into the sequential ordering of molecular events in cellular systems. We further demonstrate that identifying frequent dynamic network modules can significantly increase the signal to noise separation, despite the fact that most dynamic network modules are highly condition-specific. Finally, we note that the applicability of our algorithm is not limited to the study of PPI systems, instead it is generally applicable to the combination of any type of network and time-series data.

Field and frequency modulated sub-THz electron spin resonance spectrometer

Directory of Open Access Journals (Sweden)

Christian Caspers

2016-05-01

Full Text Available 260-GHz radiation is used for a quasi-optical electron spin resonance (ESR spectrometer which features both field and frequency modulation. Free space propagation is used to implement Martin-Puplett interferometry with quasi-optical isolation, mirror beam focusing, and electronic polarization control. Computer-aided design and polarization pathway simulation lead to the design of a compact interferometer, featuring lateral dimensions less than a foot and high mechanical stability, with all components rated for power levels of several Watts suitable for gyrotron radiation. Benchmark results were obtained with ESR standards (BDPA, DPPH using field modulation. Original high-field ESR of 4f electrons in Sm3+-doped Ceria was detected using frequency modulation. Distinct combinations of field and modulation frequency reach a signal-to-noise ratio of 35 dB in spectra of BDPA, corresponding to a detection limit of about 1014 spins.

A high precision radiation-tolerant LVDT conditioning module

CERN Document Server

Masi, A; Losito, R; Peronnard, P; Secondo, R; Spiezia, G

2014-01-01

Linear variable differential transformer (LVDT) position sensors are widely used in particle accelerators and nuclear plants, thanks to their properties of contact-less sensing, radiation tolerance, infinite resolution, good linearity and cost efficiency. Many applications require high reading accuracy, even in environments with high radiation levels, where the conditioning electronics must be located several hundred meters away from the sensor. Sometimes even at long distances the conditioning module is still exposed to ionizing radiation. Standard off-the-shelf electronic conditioning modules offer limited performances in terms of reading accuracy and long term stability already with short cables. A radiation tolerant stand-alone LVDT conditioning module has been developed using Commercial Off-The-Shelf (COTS) components. The reading of the sensor output voltages is based on a sine-fit algorithm digitally implemented on an FPGA ensuring few micrometers reading accuracy even with low signal-to-noise ratios. ...

Bent Electro-Absorption Modulator

DEFF Research Database (Denmark)

2002-01-01

by applying a variable electric or electronmagnetic field. The modulation of the complex refractive index results in a modulation of the refractive index contrast and the absorption coefficient for the waveguide at the frequency of the light. By carefully adjusting the composition of the semiconducting...... components and the applied electric field in relation to the frequency of the modulated radiation, the bending losses (and possibly coupling losses) will provide extinction of light guided by the bent waveguide section. The refractive index contract may be modulated while keeping the absorption coefficient......The present invention relates to a method and a device for modulating optical signals based on modulating bending losses in bend, quantum well semiconductor waveguide sections. The complex refractive index of the optical active semiconducting components of the waveguide section is modulated...

Modulating wind power plant output using different frequency modulation components for damping grid oscillations

DEFF Research Database (Denmark)

2017-01-01

A method, controller, wind power plant, and computer program product are disclosed for operating a wind power plant comprising a plurality of wind turbines, the wind power plant producing a plant power output. The method comprises receiving a modulation request signal indicating a requested...... modulation of the plant power output, the requested modulation specifying a modulation frequency. The method further comprises generating a respective power reference signal for each of at least two wind turbines of the plurality of wind turbines selected to fulfill the requested modulation, Each generated...... power reference signal includes a respective modulation component corresponding to a portion of the requested modulation and having a frequency different than the modulation frequency....

Modulational effects in accelerators

International Nuclear Information System (INIS)

Satogata, T.

1997-01-01

We discuss effects of field modulations in accelerators, specifically those that can be used for operational beam diagnostics and beam halo control. In transverse beam dynamics, combined effects of nonlinear resonances and tune modulations influence diffusion rates with applied tune modulation has been demonstrated. In the longitudinal domain, applied RF phase and voltage modulations provide mechanisms for parasitic halo transport, useful in slow crystal extraction. Experimental experiences with transverse tune and RF modulations are also discussed

Vertical-Cavity Surface-Emitting Lasers: Advanced Modulation Formats and Coherent Detection

DEFF Research Database (Denmark)

Rodes Lopez, Roberto

transmission link with real-time demodulation. Furthermore, advanced modulation formats are considered in this thesis to expand the state-of-the-art in high-speed short-range data transmission system based on VCSELs. First, directly modulation of a VCSEL with a 4-level pulse amplitude modulation (PAM-4) signal...... at 50 Gb/s is achieved. This is the highest data rate ever transmitted with a single VCSEL at the time of this thesis work. The capacity of this system is increased to 100 Gb/s by using polarization multiplexing emulation and forward error correction techniques. Compared to a non return-to-zero on-off...

Influence of Stationary Crossflow Modulation on Secondary Instability

Science.gov (United States)

Choudhari, Meelan M.; Li, Fei; Paredes, Pedro

2016-01-01

A likely scenario for swept wing transition on subsonic aircraft with natural laminar flow involves the breakdown of stationary crossflow vortices via high frequency secondary instability. A majority of the prior research on this secondary instability has focused on crossflow vortices with a single dominant spanwise wavelength. This paper investigates the effects of the spanwise modulation of stationary crossflow vortices at a specified wavelength by a subharmonic stationary mode. Secondary instability of the modulated crossflow pattern is studied using planar, partial-differential-equation based eigenvalue analysis. Computations reveal that weak modulation by the first subharmonic of the input stationary mode leads to mode splitting that is particularly obvious for Y-type secondary modes that are driven by the wall-normal shear of the basic state. Thus, for each Y mode corresponding to the fundamental wavelength of results in unmodulated train of crossflow vortices, the modulated flow supports a pair of secondary modes with somewhat different amplification rates. The mode splitting phenomenon suggests that a more complex stationary modulation such as that induced by natural surface roughness would yield a considerably richer spectrum of secondary instability modes. Even modest levels of subharmonic modulation are shown to have a strong effect on the overall amplification of secondary disturbances, particularly the Z-modes driven by the spanwise shear of the basic state. Preliminary computations related to the nonlinear breakdown of these secondary disturbances provide interesting insights into the process of crossflow transition in the presence of the first subharmonic of the dominant stationary vortex.

Interferon Lambda: Modulating Immunity in Infectious Diseases.

Science.gov (United States)

Syedbasha, Mohammedyaseen; Egli, Adrian

2017-01-01

Interferon lambdas (IFN-λs; IFNL1-4) modulate immunity in the context of infections and autoimmune diseases, through a network of induced genes. IFN-λs act by binding to the heterodimeric IFN-λ receptor (IFNLR), activating a STAT phosphorylation-dependent signaling cascade. Thereby hundreds of IFN-stimulated genes are induced, which modulate various immune functions via complex forward and feedback loops. When compared to the well-characterized IFN-α signaling cascade, three important differences have been discovered. First, the IFNLR is not ubiquitously expressed: in particular, immune cells show significant variation in the expression levels of and susceptibilities to IFN-λs. Second, the binding affinities of individual IFN-λs to the IFNLR varies greatly and are generally lower compared to the binding affinities of IFN-α to its receptor. Finally, genetic variation in the form of a series of single-nucleotide polymorphisms (SNPs) linked to genes involved in the IFN-λ signaling cascade has been described and associated with the clinical course and treatment outcomes of hepatitis B and C virus infection. The clinical impact of IFN-λ signaling and the SNP variations may, however, reach far beyond viral hepatitis. Recent publications show important roles for IFN-λs in a broad range of viral infections such as human T-cell leukemia type-1 virus, rotaviruses, and influenza virus. IFN-λ also potentially modulates the course of bacterial colonization and infections as shown for Staphylococcus aureus and Mycobacterium tuberculosis . Although the immunological processes involved in controlling viral and bacterial infections are distinct, IFN-λs may interfere at various levels: as an innate immune cytokine with direct antiviral effects; or as a modulator of IFN-α-induced signaling via the suppressor of cytokine signaling 1 and the ubiquitin-specific peptidase 18 inhibitory feedback loops. In addition, the modulation of adaptive immune functions via macrophage

System and method for controlling ammonia levels in a selective catalytic reduction catalyst using a nitrogen oxide sensor

Science.gov (United States)

None

2017-07-25

A system according to the principles of the present disclosure includes an air/fuel ratio determination module and an emission level determination module. The air/fuel ratio determination module determines an air/fuel ratio based on input from an air/fuel ratio sensor positioned downstream from a three-way catalyst that is positioned upstream from a selective catalytic reduction (SCR) catalyst. The emission level determination module selects one of a predetermined value and an input based on the air/fuel ratio. The input is received from a nitrogen oxide sensor positioned downstream from the three-way catalyst. The emission level determination module determines an ammonia level based on the one of the predetermined value and the input received from the nitrogen oxide sensor.

Development of Scientific Approach Based on Discovery Learning Module

Science.gov (United States)

Ellizar, E.; Hardeli, H.; Beltris, S.; Suharni, R.

2018-04-01

Scientific Approach is a learning process, designed to make the students actively construct their own knowledge through stages of scientific method. The scientific approach in learning process can be done by using learning modules. One of the learning model is discovery based learning. Discovery learning is a learning model for the valuable things in learning through various activities, such as observation, experience, and reasoning. In fact, the students’ activity to construct their own knowledge were not optimal. It’s because the available learning modules were not in line with the scientific approach. The purpose of this study was to develop a scientific approach discovery based learning module on Acid Based, also on electrolyte and non-electrolyte solution. The developing process of this chemistry modules use the Plomp Model with three main stages. The stages are preliminary research, prototyping stage, and the assessment stage. The subject of this research was the 10th and 11th Grade of Senior High School students (SMAN 2 Padang). Validation were tested by the experts of Chemistry lecturers and teachers. Practicality of these modules had been tested through questionnaire. The effectiveness had been tested through experimental procedure by comparing student achievement between experiment and control groups. Based on the findings, it can be concluded that the developed scientific approach discovery based learning module significantly improve the students’ learning in Acid-based and Electrolyte solution. The result of the data analysis indicated that the chemistry module was valid in content, construct, and presentation. Chemistry module also has a good practicality level and also accordance with the available time. This chemistry module was also effective, because it can help the students to understand the content of the learning material. That’s proved by the result of learning student. Based on the result can conclude that chemistry module based on

Design of the 12-bit Delta-Sigma Modulator using SC Technique for Vibration Sensor Output Processing

Directory of Open Access Journals (Sweden)

M. Pavlik

2012-04-01

Full Text Available The work deals with the design of the 12-bit Delta-Sigma modulator using switched capacitors (SC technique. The modulator serves to vibration sensor output processing. The first part describes the Delta-Sigma modulator parameters definition. Results of the proposed topology ideal model were presented as well. Next, the Delta-Sigma modulator circuitry on the transistor level was done. The ONSemiconductor I2T100 0.7 um CMOS technology was used for design. Then, the Delta-Sigma modulator nonidealities were simulated and implemented into the MATLAB ideal model of the modulator. The model of real Delta-Sigma modulator was derived. Consequently, modulator coefficients were optimized. Finally, the corner analysis of the Delta-Sigma modulator with the optimized coefficients was simulated. The value of SNDR = 82.2 dB (ENOB = 13.4 bits was achieved.

Dlk1/FA1 is a novel endocrine regulator of bone and fat mass and its serum level is modulated by growth hormone

DEFF Research Database (Denmark)

Abdallah, Basem; Ding, Ming; Jensen, Charlotte H

2007-01-01

Fat and bone metabolism are two linked processes regulated by several hormonal factors. Fetal antigen 1 (FA1) is the soluble form of dlk1 (delta-like 1), which is a member of the Notch-Delta family. We previously identified FA1 as a negative regulator of bone marrow mesenchymal stem cell...... differentiation. Here, we studied the effects of circulating FA1 on fat and bone mass in vivo by generating mice expressing high serum levels of FA1 (FA1 mice) using the hydrodynamic-based gene transfer procedure. We found that increased serum FA1 levels led to a significant reduction in total body weight, fat...... mass, and bone mass in a dose-dependent manner. Reduced bone mass in FA1 mice was associated with the inhibition of mineral apposition rate and bone formation rates by 58 and 72%, respectively. Because FA1 is colocalized with GH in the pituitary gland, we explored the possible modulation of serum FA1...

Attentional Modulation of Auditory Steady-State Responses

Science.gov (United States)

Mahajan, Yatin; Davis, Chris; Kim, Jeesun

2014-01-01

Auditory selective attention enables task-relevant auditory events to be enhanced and irrelevant ones suppressed. In the present study we used a frequency tagging paradigm to investigate the effects of attention on auditory steady state responses (ASSR). The ASSR was elicited by simultaneously presenting two different streams of white noise, amplitude modulated at either 16 and 23.5 Hz or 32.5 and 40 Hz. The two different frequencies were presented to each ear and participants were instructed to selectively attend to one ear or the other (confirmed by behavioral evidence). The results revealed that modulation of ASSR by selective attention depended on the modulation frequencies used and whether the activation was contralateral or ipsilateral. Attention enhanced the ASSR for contralateral activation from either ear for 16 Hz and suppressed the ASSR for ipsilateral activation for 16 Hz and 23.5 Hz. For modulation frequencies of 32.5 or 40 Hz attention did not affect the ASSR. We propose that the pattern of enhancement and inhibition may be due to binaural suppressive effects on ipsilateral stimulation and the dominance of contralateral hemisphere during dichotic listening. In addition to the influence of cortical processing asymmetries, these results may also reflect a bias towards inhibitory ipsilateral and excitatory contralateral activation present at the level of inferior colliculus. That the effect of attention was clearest for the lower modulation frequencies suggests that such effects are likely mediated by cortical brain structures or by those in close proximity to cortex. PMID:25334021

Attentional modulation of auditory steady-state responses.

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Yatin Mahajan

Full Text Available Auditory selective attention enables task-relevant auditory events to be enhanced and irrelevant ones suppressed. In the present study we used a frequency tagging paradigm to investigate the effects of attention on auditory steady state responses (ASSR. The ASSR was elicited by simultaneously presenting two different streams of white noise, amplitude modulated at either 16 and 23.5 Hz or 32.5 and 40 Hz. The two different frequencies were presented to each ear and participants were instructed to selectively attend to one ear or the other (confirmed by behavioral evidence. The results revealed that modulation of ASSR by selective attention depended on the modulation frequencies used and whether the activation was contralateral or ipsilateral. Attention enhanced the ASSR for contralateral activation from either ear for 16 Hz and suppressed the ASSR for ipsilateral activation for 16 Hz and 23.5 Hz. For modulation frequencies of 32.5 or 40 Hz attention did not affect the ASSR. We propose that the pattern of enhancement and inhibition may be due to binaural suppressive effects on ipsilateral stimulation and the dominance of contralateral hemisphere during dichotic listening. In addition to the influence of cortical processing asymmetries, these results may also reflect a bias towards inhibitory ipsilateral and excitatory contralateral activation present at the level of inferior colliculus. That the effect of attention was clearest for the lower modulation frequencies suggests that such effects are likely mediated by cortical brain structures or by those in close proximity to cortex.