Science.gov

Sample records for activity varied widely

  1. Additional Surgery after Breast-Conserving Surgery Varies Widely

    Cancer.gov

    A study published in the Feb. 1, 2012, issue of JAMA found that the number of women who have one or more additional surgeries to remove suspected residual tumor tissue (re-excisions) following breast-conserving surgery (BCS) for breast cancer varies widely across surgeons and hospitals.

  2. Genome-wide DNA polymorphism analyses using VariScan

    PubMed Central

    Hutter, Stephan; Vilella, Albert J; Rozas, Julio

    2006-01-01

    Background DNA sequence polymorphisms analysis can provide valuable information on the evolutionary forces shaping nucleotide variation, and provides an insight into the functional significance of genomic regions. The recent ongoing genome projects will radically improve our capabilities to detect specific genomic regions shaped by natural selection. Current available methods and software, however, are unsatisfactory for such genome-wide analysis. Results We have developed methods for the analysis of DNA sequence polymorphisms at the genome-wide scale. These methods, which have been tested on a coalescent-simulated and actual data files from mouse and human, have been implemented in the VariScan software package version 2.0. Additionally, we have also incorporated a graphical-user interface. The main features of this software are: i) exhaustive population-genetic analyses including those based on the coalescent theory; ii) analysis adapted to the shallow data generated by the high-throughput genome projects; iii) use of genome annotations to conduct a comprehensive analyses separately for different functional regions; iv) identification of relevant genomic regions by the sliding-window and wavelet-multiresolution approaches; v) visualization of the results integrated with current genome annotations in commonly available genome browsers. Conclusion VariScan is a powerful and flexible suite of software for the analysis of DNA polymorphisms. The current version implements new algorithms, methods, and capabilities, providing an important tool for an exhaustive exploratory analysis of genome-wide DNA polymorphism data. PMID:16968531

  3. Frontal Neurons Modulate Memory Retrieval across Widely Varying Temporal Scales

    ERIC Educational Resources Information Center

    Zhang, Wen-Hua; Williams, Ziv M.

    2015-01-01

    Once a memory has formed, it is thought to undergo a gradual transition within the brain from short- to long-term storage. This putative process, however, also poses a unique problem to the memory system in that the same learned items must also be retrieved across broadly varying time scales. Here, we find that neurons in the ventrolateral…

  4. Presence of diadenosine 5',5''' -P1, P4-tetraphosphate (Ap4A) in mamalian cells in levels varying widely with proliferative activity of the tissue: a possible positive "pleiotypic activator".

    PubMed Central

    Rapaport, E; Zamecnik, P C

    1976-01-01

    An accurate assay of diadenosine 5',5'''- P1,P4-tetraphosphate [A(5') pppp(5')A], which was shown to be formed in vitro in the backreaction of the amino acid activation step, has been developed in various cell lines in culture and in normal mouse liver or hepatoma in vivo. Use of radioactive labeling of acid-soluble nucleotides to high specific activity followed by chromatographic separation techniques yielded levels of Ap4A varying from 5 to 0.05 muM (from 30 pmol/mg of protein to 0.15 pmol), depending on the doubling time of the cell line or the proliferative state of the cells. The levels of Ap4A incells is inversely related to their doubling time, varying from 0.1 X 10(-4) of the cellular ATP levels in slowly growing cells to 20 X 10(-4) of the ATP levels of cells with rapid doubling times. The steady-state levels of ATP of different cell lines, although showing some fluctuations, are not related to the doubling time of the cells. Arrest of cellular proliferation by serum deprivation or amino acid starvation, which does not alter the cellular ATP levels more than 2-fold, does nevertheless cause a decrease of 30 to 50-fold in the Ap4A levels. Inhibition of protein synthesis by pactamycin or puromycin, or inhibition of DNA synthesis by hydroxyurea, leads to a more dramatic decrease of 50 to 100-fold in intracellular Ap4A levels. The metabolic lability of Ap4A is also demonstrated by its rapid depletion after decreases in the ATP/ADP ratio. The possibility of Ap4A being a metabolic "signal nucleotide" that is formed at the onset of protein synthesis and is active in positive growth regulation (positive pleiotypic activation) is discussed. PMID:1069282

  5. Clinical Trial Results Vary Widely, But Always Advance Research | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Clinical Trials Clinical Trial Results Vary Widely, But Always Advance Research ... very emotional." Should You Be Interested in a Clinical Trial People volunteer to take part in clinical ...

  6. Active spectral sensor evaluation under varying conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant stress has been estimated by spectral signature using both passive and active sensors. As optical sensors measure reflected light from a target, changes in illumination characteristics critically affect sensor response. Active sensors are of benefit in minimizing uncontrolled illumination effe...

  7. Surface and canopy fuels vary widely in 24-yr old postfire lodgepole pine forests

    NASA Astrophysics Data System (ADS)

    Nelson, K. N.; Turner, M.; Romme, W. H.; Tinker, D. B.

    2013-12-01

    Extreme fire seasons have become common in western North America, and the extent of young postfire forests has grown as fire frequency and annual area burned have increased. These young forests will set the stage for future fires, but an assessment of fuel loads in young forests is lacking. The rate of fuel re-accumulation and fuels variability in postfire forest landscapes is needed to anticipate future fire occurrence and behavior in the American West. We studied fuel characteristics in young lodgepole pine forests that regenerated after the 1988 fires in Yellowstone National Park to address two questions: (1) How do surface fuel characteristics change with time-since-fire? (2) How do canopy and surface fuels vary across the Yellowstone landscape 24 years postfire? During summer 2012, we re-measured surface fuels in 11 plots that were established in 1996 (8 yrs post fire), and we measured surface and canopy fuels in 82 stands (each 0.25 ha) distributed across the Yellowstone post-1988 fire landscape. In the remeasured plots, surface fuel loads generally increased over the last 16 years. One-hr fuels did not change between sample dates, but all other fuel classes (i.e., 10-hr, 100-hr, and 1000-hr) increased by a factor of two or three. Within the sample timeframe, variability of fuel loads within stands decreased significantly. The coefficients of variation decreased for all fuel classes by 23% to 67%. Data from the 82 plots revealed that canopy and surface fuels in 24-year-old stands varied tremendously across the Yellowstone landscape. Live tree densities spanned 0 to 344,067 trees ha-1, producing a mean available canopy fuel load of 7.7 Mg ha-1 and a wide range from 0 to 47 Mg ha-1. Total surface fuel loads averaged 130 Mg ha-1 and ranged from 49 to 229 Mg ha-1, of which 90% was in the 1000-hr fuel class. The mass of fine surface fuels (i.e., litter/duff, 1-hr, 10-hr, and herbaceous fuels) and canopy fuels (i.e., foliage and 1-hr branches) were strongly and

  8. Nutrient Intake Values for Folate during Pregnancy and Lactation Vary Widely around the World

    PubMed Central

    Stamm, Rosemary A.; Houghton, Lisa A.

    2013-01-01

    Folate is a B-vitamin with particular importance during reproduction due to its role in the synthesis and maintenance of DNA. Folate is well known for its role in preventing neural tube defects (NTDs) during the periconceptional period. There is also an increased need for folate throughout pregnancy to support optimal growth and development of the fetus and blood volume expansion and tissue growth of the mother. During lactation, women are at risk of folate deficiency due to increased demands to accommodate milk folate levels. Nutrient Intake Values (NIVs) for folate have been calculated to take into account additional needs during pregnancy and lactation. However, these values vary widely between countries. For example, the folate requirement that is set to meet the needs of almost all healthy women during pregnancy varies from 300 µg/day in the United Kingdom to 750 µg/day in Mexico. Currently, there is no accepted standardized terminology or framework for establishing NIVs. This article reviews country-specific NIVs for folate during pregnancy and lactation and the basis for setting these reference values. PMID:24084052

  9. Chloroplast movement behavior varies widely among species and does not correlate with high light stress tolerance.

    PubMed

    Königer, Martina; Bollinger, Nicole

    2012-08-01

    It is well known that chloroplasts move in response to changes in blue light intensity in order to optimize light interception, however, little is known about interspecific variation and the relative importance of this mechanism for the high light stress tolerance of plants. We characterized chloroplast movement behavior as changes in light transmission through a leaf in a variety of species ranging from ferns to monocots and eudicots and found a wide spectrum of responses. Most species exhibited a distinct accumulation response compared to the dark positioning, and all species showed a distinct avoidance response. The speed with which transmission values changed during the avoidance response was consistently faster than that during the accumulation response and speeds varied greatly between species. Plants thriving in higher growth light intensities showed greater degrees of accumulation responses and faster changes in transmission than those that prefer lower light intensities. In some species, the chloroplasts on both the adaxial and abaxial leaf surfaces changed their positioning in response to light, while in other species only the chloroplasts on one leaf side responded. No correlation was found between high light stress tolerance and the speed or degree of transmission changes, indicating that plants can compensate for slow and limited transmission changes using other photoprotective mechanisms.

  10. The HRA/Solarium Project: Processing of Widely Varying High- and Medium-Level Waste

    SciTech Connect

    Willems, M.; Luycx, P.; Gilis, R.; Belgoprocess; Renard, Cl.; Reyniers, H.; Cuchet, J. M.

    2003-02-26

    Starting in 2003, Belgoprocess will proceed with the treatment and conditioning of some 200 m{sup 3} of widely varying high- and medium-level waste from earlier research and development work, to meet standard acceptance criteria for later disposal. The gross volume of primary and secondary packages amounts to 2,600 m{sup 3}. The waste has been kept in decay storage for up to 30 years. The project was started in 1997. Operation of the various processing facilities will take 7-8 years. The overall volume of conditioned waste will be of the order of 800 m{sup 3}. All conditioned waste will be stored in appropriate storage facilities onsite. At present (November, 2002), a new processing facility has been constructed, the functional tests of the equipment have been performed and the startup phase has been started. Several cells of the Pamela vitrification facility onsite will be adapted for the treatment of high-level and highly a-contaminated waste; low-level a/a waste will be treated in the existing facility for super compaction and conditioning by embedding into cement (CILVA). The bulk of these waste, of which 95% are solids, the remainder consisting of mainly solidified liquids, have been produced between 1967 and 1988. They originate from various research programs and reactor operation at the Belgian nuclear energy research centre SCK CEN, isotope production, decontamination and dismantling operations.

  11. State Regulation Of Freestanding Emergency Departments Varies Widely, Affecting Location, Growth, And Services Provided.

    PubMed

    Gutierrez, Catherine; Lindor, Rachel A; Baker, Olesya; Cutler, David; Schuur, Jeremiah D

    2016-10-01

    Freestanding emergency departments (EDs), which offer emergency medical care at sites separate from hospitals, are a rapidly growing alternative to traditional hospital-based EDs. We evaluated state regulations of freestanding EDs and describe their effect on the EDs' location, staffing, and services. As of December 2015, thirty-two states collectively had 400 freestanding EDs. Twenty-one states had regulations that allowed freestanding EDs, and twenty-nine states did not have regulations that applied specifically to such EDs (one state had hospital regulations that precluded them). State policies regarding freestanding EDs varied widely, with no standard requirements for location, staffing patterns, or clinical capabilities. States requiring freestanding EDs to have a certificate of need had fewer of such EDs per capita than states without such a requirement. For patients to better understand the capabilities and costs of freestanding EDs and to be able to choose the most appropriate site of emergency care, consistent state regulation of freestanding EDs is needed.

  12. Management of Inflammatory Bowel Disease during Pregnancy and Breastfeeding Varies Widely: A Need for Further Education

    PubMed Central

    Goodman, Karen Jean; Hegadoren, Kathleen M.; Dieleman, Levinus Albert; Fedorak, Richard Neil

    2016-01-01

    Background. Inflammatory bowel disease (IBD) affects patients in their young reproductive years. Women with IBD require maintenance therapies during pregnancy and breastfeeding. However, physician management of IBD during pregnancy and breastfeeding has not been well characterized. Objective. To characterize physician perceptions and management of IBD during pregnancy and breastfeeding. Methods. A cross-sectional survey of Canadian physicians who are involved in the care of women with IBD was conducted. The survey included multiple-choice and Likert scale questions about perceptions and practice patterns regarding the management of IBD during pregnancy and breastfeeding. Results. 183 practicing physicians completed the questionnaire: 97/183 (53.0%) gastroenterologists; 75/183 (41.0%) general practitioners; and 11/183 (6.0%) other physicians. Almost half (87/183, 47.5%) of the physicians felt comfortable managing pregnant IBD patients. For specified IBD medications, proportions of physicians who indicated they would continue them during pregnancy were as follows: sulfasalazine, 47.4%; oral mesalamine, 67.0%; topical mesalamine, 70.3%; oral prednisone, 68.0%; topical prednisone, 78.0%; oral budesonide, 61.6%; topical budesonide, 75.0%; ciprofloxacin, 15.3%; metronidazole, 31.4%; azathioprine, 57.1%; methotrexate, 2.8%; infliximab, 55.6%; adalimumab, 78.1%. Similar proportions of physicians would continue these medications during breastfeeding. A higher proportion of gastroenterologists than nongastroenterologists indicated appropriate use of these IBD medications during pregnancy and breastfeeding. Conclusions. Physician management of IBD during pregnancy and breastfeeding varies widely. Relative to other physicians, responses of gastroenterologists more frequently reflected best practices pertaining to medications for control of IBD during pregnancy and breastfeeding. There is a need for further education regarding the management of IBD during pregnancy and

  13. Basic Business and Economics: Varied Activities Encourage Active Student Involvement.

    ERIC Educational Resources Information Center

    Baker, Robert Lee, Jr.

    1978-01-01

    Describes a variety of activities for the basic business classroom, such as having guest speakers, question-and-answer sessions, simulations, role playing, debates, small group work, field trips, games, and individualized instruction. Includes a report of business teachers' knowledge of and attitudes toward these activities. (MF)

  14. Evaluation of active appearance models in varying background conditions

    NASA Astrophysics Data System (ADS)

    Kowalski, Marek; Naruniec, Jacek

    2013-10-01

    In this paper we present an evaluation of the chosen versions of Active Appearance Models (AAM) in varying background conditions. Algorithms were tested on a subset of the CMU PIE database and chosen background im- ages. Our experiments prove, that the accuracy of those methods is strictly correlated with the used background, where the differences in the success rate differ even up to 50%.

  15. Human sympathetic outflows to skin and muscle target organs fluctuate concordantly over a wide range of time-varying frequencies.

    PubMed

    Bernjak, Alan; Cui, Jian; Iwase, Satoshi; Mano, Tadaaki; Stefanovska, Aneta; Eckberg, Dwain L

    2012-01-15

    Frequency-domain analyses of simultaneously recorded skin and muscle sympathetic nerve activities may yield unique information on otherwise obscure central processes governing human neural outflows. We used wavelet transform and wavelet phase coherence methods to analyse integrated skin and muscle sympathetic nerve activities and haemodynamic fluctuations, recorded from nine healthy supine young men. We tested two null hypotheses: (1) that human skin and muscle sympathetic nerve activities oscillate congruently; and (2) that whole-body heating affects these neural outflows and their haemodynamic consequences in similar ways. Measurements included peroneal nerve skin and tibial nerve muscle sympathetic activities; the electrocardiogram; finger photoplethysmographic arterial pressure; respiration (controlled at 0.25 Hz, and registered with a nasal thermistor); and skin temperature, sweating, and laser-Doppler skin blood flow. We made recordings at ∼27°C, for ∼20 min, and then during room temperature increases to ∼38°C, over 35 min. We analysed data with a wavelet transform, using the Morlet mother wavelet and wavelet phase coherence, to determine the frequencies and coherences of oscillations over time. At 27°C, skin and muscle nerve activities oscillated coherently, at ever-changing frequencies between 0.01 and the cardiac frequency (∼1 Hz). Heating significantly augmented oscillations of skin sympathetic nerve activity and skin blood flow, arterial pressure, and R-R intervals, over a wide range of low frequencies, and modestly reduced coordination between skin and muscle sympathetic oscillations. These results suggest that human skin and muscle sympathetic motoneurones are similarly entrained by external influences, including those of arterial baroreceptors, respiration, and other less well-defined brainstem oscillators. Our study provides strong support for the existence of multiple, time-varying central sympathetic neural oscillators in human subjects.

  16. Widely varying giant Goos-Hänchen shifts from Airy beams at nonlinear interfaces.

    PubMed

    Chamorro-Posada, Pedro; Sánchez-Curto, Julio; Aceves, Alejandro B; McDonald, Graham S

    2014-03-15

    We present a numerical study of the giant Goos-Hänchen shifts (GHSs) obtained from an Airy beam impinging on a nonlinear interface. To avoid any angular restriction associated with the paraxial approximation, the analysis is based on the nonlinear Helmholtz equation. We report the existence of nonstandard nonlinear GHSs displaying an extreme sensitivity to the input intensity and the existence of multiple critical values. These intermittent and oscillatory regimes can be explained in terms of competition between critical coupling to a surface mode and soliton emission from the refracted beam component and how this interplay varies with localization of the initial Airy beam.

  17. Constraints on global fire activity vary across a resource gradient.

    PubMed

    Krawchuk, Meg A; Moritz, Max A

    2011-01-01

    We provide an empirical, global test of the varying constraints hypothesis, which predicts systematic heterogeneity in the relative importance of biomass resources to burn and atmospheric conditions suitable to burning (weather/climate) across a spatial gradient of long-term resource availability. Analyses were based on relationships between monthly global wildfire activity, soil moisture, and mid-tropospheric circulation data from 2001 to 2007, synthesized across a gradient of long-term averages in resources (net primary productivity), annual temperature, and terrestrial biome. We demonstrate support for the varying constraints hypothesis, showing that, while key biophysical factors must coincide for wildfires to occur, the relative influence of resources to burn and moisture/weather conditions on fire activity shows predictable spatial patterns. In areas where resources are always available for burning during the fire season, such as subtropical/tropical biomes with mid-high annual long-term net primary productivity, fuel moisture conditions exert their strongest constraint on fire activity. In areas where resources are more limiting or variable, such as deserts, xeric shrublands, or grasslands/savannas, fuel moisture has a diminished constraint on wildfire, and metrics indicating availability of burnable fuels produced during the antecedent wet growing seasons reflect a more pronounced constraint on wildfire. This macro-scaled evidence for spatially varying constraints provides a synthesis with studies performed at local and regional scales, enhances our understanding of fire as a global process, and indicates how sensitivity to future changes in temperature and precipitation may differ across the world.

  18. A coherent digital demodulator for multiple signal formats and widely varying data rates

    NASA Astrophysics Data System (ADS)

    McGuffin, Bruce F.

    The Tracking and Data Relay Satellite System (TDRSS) uses four ground station demodulators for K-band signals with data rates from 1 kb/s to 300 Mb/s. The author discusses the feasibility of replacing these demodulators with a single digital demodulator that may be reconfigured by altering stored parameters to accommodate all signal formats and data rates. This implementation will reduce total ground station cost and facilitate automation of ground station operation. Analysis of system performance concentrates on the carrier tracking loop. Analytic and simulation results relate system performance to parameter values and signal format as data rate and power vary independently on the In-phase and quadrature channels. It is demonstrated that a single digital demodulator can support TDRSS-compatible signals at data rates conservatively extending from 1K symbols/s to 10M symbols/s, using off-the-shelf hardware with 6 or more bits of accuracy.

  19. The deforestation debate; estimates vary widely over the extent of forest loss

    SciTech Connect

    Monastersky, R.

    1993-07-10

    While tropical forests are vanishing at a disturbing rate, the wide-spread disagreement over deforestation estimates makes it difficult for government officials and scientists to assess the problem. In turn this hampers efforts to gauge the threat of related issues such as habitat destruction and global warming. Creating more confusion is the realization that partly deforested, but not stripped, lands have not been completely taken into account. In addition lands in tropical regions but outside the tropical rain forest are poorly represented. This article uses Brazil as an example of the conflicting estimates. The efforts of the United Nations Food and Agriculture Organization (FAO) to improve its estimates are described. An on-going NASA project to help is also described.

  20. Estimating a scale-change effect for time-varying phenotypes in genome-wide association studies

    PubMed Central

    Chen, Ying Qing; Zhang, Xinyi; Zhao, Lue-Ping

    2012-01-01

    Summary The Cox proportional hazards model has been used widely in genome-wide association (GWA) studies of censored time-varying phenotypes to investigate disease association expressed by the relative hazards. In this paper, we instead apply the so-called accelerated hazards model to explore a novel time scale-change genotypic association, which is not necessarily able to be identified by the traditional Cox models. Our application is motivated and demonstrated by a GWA study of hematopoietic stem cell transplantation cohort.

  1. Pathogen exposure varies widely among sympatric populations of wild and domestic felids across the United States.

    PubMed

    Carver, Scott; Bevins, Sarah N; Lappin, Michael R; Boydston, Erin E; Lyren, Lisa M; Alldredge, Mathew; Logan, Kenneth A; Sweanor, Linda L; Riley, Seth P D; Serieys, Laurel E K; Fisher, Robert N; Vickers, T Winston; Boyce, Walter; Mcbride, Roy; Cunningham, Mark C; Jennings, Megan; Lewis, Jesse; Lunn, Tamika; Crooks, Kevin R; Vandewoude, Sue

    2016-03-01

    Understanding how landscape, host, and pathogen traits contribute to disease exposure requires systematic evaluations of pathogens within and among host species and geographic regions. The relative importance of these attributes is critical for management of wildlife and mitigating domestic animal and human disease, particularly given rapid ecological changes, such as urbanization. We screened > 1000 samples from sympatric populations of puma (Puma concolor), bobcat (Lynx rufus), and domestic cat (Felis catus) across urban gradients in six sites, representing three regions, in North America for exposure to a representative suite of bacterial, protozoal, and viral pathogens (Bartonella sp., Toxoplasma gondii, feline herpesvirus-1, feline panleukopenea virus, feline calicivirus, and feline immunodeficiency virus). We evaluated prevalence within each species, and examined host trait and land cover determinants of exposure; providing an unprecedented analysis of factors relating to potential for infections in domesticated and wild felids. Prevalence differed among host species (highest for puma and lowest for domestic cat) and was greater for indirectly transmitted pathogens. Sex was inconsistently predictive of exposure to directly transmitted pathogens only, and age infrequently predictive of both direct and indirectly transmitted pathogens. Determinants of pathogen exposure were widely divergent between the wild felid species. For puma, suburban land use predicted increased exposure to Bartonella sp. in southern California, and FHV-1 exposure increased near urban edges in Florida. This may suggest interspecific transmission with domestic cats via flea vectors (California) and direct contact (Florida) around urban boundaries. Bobcats captured near urban areas had increased exposure to T. gondii in Florida, suggesting an urban source of prey Bobcats captured near urban areas in Colorado and Florida had higher FIV exposure, possibly suggesting increased intraspecific

  2. Pathogen exposure varies widely among sympatric populations of wild and domestic felids across the United States

    USGS Publications Warehouse

    Carver, Scott; Bevins, Sarah N.; Lappin, Michael R.; Boydston, Erin E.; Lyren, Lisa M.; Alldredge, Mathew W.; Logan, Kenneth A.; Sweanor, Linda L.; Riley, Seth P.D.; Serieys, Laurel E.K.; Fisher, Robert N.; Vickers, T. Winston; Boyce, Walter M.; McBride, Roy; Cunnigham, Mark C.; Jennings, Megan; Lewis, Jesse S.; Lunn, Tamika; Crooks, Kevin R.; VandeWoude, Sue

    2016-01-01

    Understanding how landscape, host, and pathogen traits contribute to disease exposure requires systematic evaluations of pathogens within and among host species and geographic regions. The relative importance of these attributes is critical for management of wildlife and mitigating domestic animal and human disease, particularly given rapid ecological changes, such as urbanization. We screened >1,000 samples from sympatric populations of puma (Puma concolor), bobcat (Lynx rufus) and domestic cat (Felis catus) across urban gradients in six sites, representing three regions, in North America for exposure to a representative suite of bacterial, protozoal and viral pathogens (Bartonella sp., Toxoplasma gondii, feline herpesvirus-1, feline panleukopenea virus, feline calicivirus, feline immunodeficiency virus). We evaluated prevalence within each species, and examined host trait and land cover determinants of exposure-providing an unprecedented analysis of factors relating to potential for infections in domesticated and wild felids. Prevalence differed among host species (highest for puma and lowest for domestic cat) and was greater for indirectly transmitted pathogens. Sex was inconsistently predictive of exposure to directly transmitted pathogens only, and age infrequently predictive of both direct and indirectly transmitted pathogens. Determinants of pathogen exposure were widely divergent between the wild felid species. For puma, suburban landuse predicted increased exposure to Bartonella sp. in southern California, and FHV-1 exposure increased near urban edges in Florida. This may suggest inter-specific transmission with domestic cats via flea vectors (California) and direct contact (Florida) around urban boundaries. Bobcats captured near urban areas had increased exposure to T. gondii in Florida, suggesting an urban source of prey. Bobcats captured near urban areas in Colorado and Florida had higher FIV exposure, possibly suggesting increased intra

  3. The Activity of Antimicrobial Surfaces Varies by Testing Protocol Utilized

    PubMed Central

    Campos, Matias D.; Zucchi, Paola C.; Phung, Ann; Leonard, Steven N.; Hirsch, Elizabeth B.

    2016-01-01

    Background Contaminated hospital surfaces are an important source of nosocomial infections. A major obstacle in marketing antimicrobial surfaces is a lack of efficacy data based on standardized testing protocols. Aim We compared the efficacy of multiple testing protocols against several “antimicrobial” film surfaces. Methods Four clinical isolates were used: one Escherichia coli, one Klebsiella pneumoniae, and two Staphylococcus aureus strains. Two industry methods (modified ISO 22196 and ASTM E2149), a “dried droplet”, and a “transfer” method were tested against two commercially available antimicrobial films, one film in development, an untreated control, and a positive (silver) control film. At 2 (only ISO) and 24 hours following inoculation, bacteria were collected from film surfaces and enumerated. Results Compared to untreated films in all protocols, there were no significant differences in recovery on either commercial brand at 2 or 24 hours after inoculation. The silver surface demonstrated significant microbicidal activity (mean loss 4.9 Log10 CFU/ml) in all methods and time points with the exception of 2 hours in the ISO protocol and the transfer method. Using our novel droplet method, no differences between placebo and active surfaces were detected. The surface in development demonstrated variable activity depending on method, organism, and time point. The ISO demonstrated minimal activity at 2 hours but significant activity at 24 hours (mean 4.5 Log10 CFU/ml difference versus placebo). The ASTEM protocol exhibited significant differences in recovery of staphylococci (mean 5 Log10 CFU/ml) but not Gram-negative isolates (10 fold decrease). Minimal activity was observed with this film in the transfer method. Conclusions Varying results between protocols suggested that efficacy of antimicrobial surfaces cannot be easily and reproducibly compared. Clinical use should be considered and further development of representative methods is needed. PMID

  4. Guaranteed Student Loans: Profits of Secondary Market Lenders Vary Widely. United States General Accounting Office Briefing Report to Congressional Requesters.

    ERIC Educational Resources Information Center

    General Accounting Office, Washington, DC. Div. of Human Resources.

    This report was prepared to determine lenders' rates of return or profitability on Stafford loans in their portfolios, reasons for varying levels of profitability among institutions that hold such loans, and the effect of 1986 subsidy reductions on these lenders' profitability. The study focused on the activities of lenders that purchase Stafford…

  5. H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets

    PubMed Central

    Yang, Guohua; Marinova-Petkova, Atanaska; Kaplan, Bryan S.; Webby, Richard J.

    2017-01-01

    A pandemic-capable influenza virus requires a hemagglutinin (HA) surface glycoprotein that is immunologically unseen by most people and is capable of supporting replication and transmission in humans. HA stabilization has been linked to 2009 pH1N1 pandemic potential in humans and H5N1 airborne transmissibility in the ferret model. Swine have served as an intermediate host for zoonotic influenza viruses, yet the evolutionary pressure exerted by this host on HA stability was unknown. For over 70 contemporary swine H1 and H3 isolates, we measured HA activation pH to range from pH 5.1 to 5.9 for H1 viruses and pH 5.3 to 5.8 for H3 viruses. Thus, contemporary swine isolates vary widely in HA stability, having values favored by both avian (pH >5.5) and human and ferret (pH ≤5.5) species. Using an early 2009 pandemic H1N1 (pH1N1) virus backbone, we generated three viruses differing by one HA residue that only altered HA stability: WT (pH 5.5), HA1-Y17H (pH 6.0), and HA2-R106K (pH 5.3). All three replicated in pigs and transmitted from pig-to-pig and pig-to-ferret. WT and R106 viruses maintained HA genotype and phenotype after transmission. Y17H (pH 6.0) acquired HA mutations that stabilized the HA protein to pH 5.8 after transmission to pigs and 5.5 after transmission to ferrets. Overall, we found swine support a broad range of HA activation pH for contact transmission and many recent swine H1N1 and H3N2 isolates have stabilized (human-like) HA proteins. This constitutes a heightened pandemic risk and underscores the importance of ongoing surveillance and control efforts for swine viruses. PMID:28282440

  6. Innovation diffusion on time-varying activity driven networks

    NASA Astrophysics Data System (ADS)

    Rizzo, Alessandro; Porfiri, Maurizio

    2016-01-01

    Since its introduction in the 1960s, the theory of innovation diffusion has contributed to the advancement of several research fields, such as marketing management and consumer behavior. The 1969 seminal paper by Bass [F.M. Bass, Manag. Sci. 15, 215 (1969)] introduced a model of product growth for consumer durables, which has been extensively used to predict innovation diffusion across a range of applications. Here, we propose a novel approach to study innovation diffusion, where interactions among individuals are mediated by the dynamics of a time-varying network. Our approach is based on the Bass' model, and overcomes key limitations of previous studies, which assumed timescale separation between the individual dynamics and the evolution of the connectivity patterns. Thus, we do not hypothesize homogeneous mixing among individuals or the existence of a fixed interaction network. We formulate our approach in the framework of activity driven networks to enable the analysis of the concurrent evolution of the interaction and individual dynamics. Numerical simulations offer a systematic analysis of the model behavior and highlight the role of individual activity on market penetration when targeted advertisement campaigns are designed, or a competition between two different products takes place.

  7. Genome-wide CpG island methylation and intergenic demethylation propensities vary among different tumor sites

    PubMed Central

    Lee, Seung-Tae; Wiemels, Joseph L.

    2016-01-01

    The epigenetic landscape of cancer includes both focal hypermethylation and broader hypomethylation in a genome-wide manner. By means of a comprehensive genomic analysis on 6637 tissues of 21 tumor types, we here show that the degrees of overall methylation in CpG island (CGI) and demethylation in intergenic regions, defined as ‘backbone’, largely vary among different tumors. Depending on tumor type, both CGI methylation and backbone demethylation are often associated with clinical, epidemiological and biological features such as age, sex, smoking history, anatomic location, histological type and grade, stage, molecular subtype and biological pathways. We found connections between CGI methylation and hypermutability, microsatellite instability, IDH1 mutation, 19p gain and polycomb features, and backbone demethylation with chromosomal instability, NSD1 and TP53 mutations, 5q and 19p loss and long repressive domains. These broad epigenetic patterns add a new dimension to our understanding of tumor biology and its clinical implications. PMID:26464434

  8. Pre-existing smooth muscle cells contribute to neointimal cell repopulation at an incidence varying widely among individual lesions

    PubMed Central

    Yang, Pu; Hong, Michael S.; Fu, Chunhua; Schmit, Bradley M.; Su, Yunchao; Berceli, Scott A.; Jiang, Zhihua

    2015-01-01

    Background With the diverse origin of neointimal cells, previous studies have documented differences of neointimal cell-lineage composition across models, but the animal-to-animal difference has not attracted much attention though the cellular heterogeneity may impact neointimal growth and its response to therapeutic interventions. Methods The R26R+;Myh11-CreER+ and R26R+;Scl-CreER+ mice were utilized to attach LacZ tags to the pre-existing smooth muscle cells (SMCs) and endothelial cells (ECs), respectively. Neointimal lesions were created via complete ligation of the common carotid artery (CCA) and transluminal injury to the femoral artery (FA). Results LacZ-tagged SMCs were physically relocated from media to neointima and changed to a de-differentiated phenotype in both CCA and FA lesions. The content of SMCs in the neointimal tissue, however, varied widely among specimens, ranging from 5–70% and 0–85%, with an average at low levels of 27% and 29% in CCA (n=15) and FA (n=15) lesions, respectively. Bone marrow cells, while able to home to the injured arteries, did not differentiate fully into SMCs after either type of injury. Pre-existing ECs were located in the sub-endothelial region and produced mesenchymal marker α-actin, indicating endothelial-mesenchymal-transition (EndoMT), however, EC-derived cells represented only 7% and 3% of the total neointimal cell pool of CCA (n=7) and FA (n=7) lesions, respectively. ECs located on the luminal surface exhibited little evidence for EndoMT. Conclusion Neointimal hyperplasia proceeds with a wide range of variation in its cellular composition between individual lesions. Relative to ECs, SMCs are major contributors to the lesion-to-lesion heterogeneity in neointimal cell-lineage composition. PMID:26387788

  9. Motoneuron and sensory neuron plasticity to varying neuromuscular activity levels

    NASA Technical Reports Server (NTRS)

    Ishihara, Akihiko; Roy, Roland R.; Ohira, Yoshinobu; Edgerton, V. Reggie

    2002-01-01

    The size and phenotypic properties of the neural and muscular elements of the neuromuscular unit are matched under normal conditions. When subjected to chronic decreases or increases in neuromuscular activity, however, the adaptations in these properties are much more limited in the neural compared with the muscular elements.

  10. Resting Brain Activity Varies with Dream Recall Frequency Between Subjects

    PubMed Central

    Eichenlaub, Jean-Baptiste; Nicolas, Alain; Daltrozzo, Jérôme; Redouté, Jérôme; Costes, Nicolas; Ruby, Perrine

    2014-01-01

    Dreaming is still poorly understood. Notably, its cerebral underpinning remains unclear. Neuropsychological studies have shown that lesions in the temporoparietal junction (TPJ) and/or the white matter of the medial prefrontal cortex (MPFC) lead to the global cessation of dream reports, suggesting that these regions of the default mode network have key roles in the dreaming process (forebrain ‘dream-on' hypothesis). To test this hypothesis, we measured regional cerebral blood flow (rCBF) using [15O]H2O positron emission tomography in healthy subjects with high and low dream recall frequencies (DRFs) during wakefulness (rest) and sleep (rapid eye movement (REM) sleep, N2, and N3). Compared with Low recallers (0.5±0.3 dream recall per week in average), High recallers (5.2±1.4) showed higher rCBF in the TPJ during REM sleep, N3, and wakefulness, and in the MPFC during REM sleep and wakefulness. We demonstrate that the resting states of High recallers and Low recallers differ during sleep and wakefulness. It coheres with previous ERP results and confirms that a high/low DRF is associated with a specific functional organization of the brain. These results support the forebrain ‘dream-on' hypothesis and suggest that TPJ and MPFC are not only involved in dream recall during wakefulness but also have a role in dreaming during sleep (production and/or encoding). Increased activity in the TPJ and MPFC might promote the mental imagery and/or memory encoding of dreams. Notably, increased activity in TPJ might facilitate attention orienting toward external stimuli and promote intrasleep wakefulness, facilitating the encoding of the dreams in memory. PMID:24549103

  11. Resting brain activity varies with dream recall frequency between subjects.

    PubMed

    Eichenlaub, Jean-Baptiste; Nicolas, Alain; Daltrozzo, Jérôme; Redouté, Jérôme; Costes, Nicolas; Ruby, Perrine

    2014-06-01

    Dreaming is still poorly understood. Notably, its cerebral underpinning remains unclear. Neuropsychological studies have shown that lesions in the temporoparietal junction (TPJ) and/or the white matter of the medial prefrontal cortex (MPFC) lead to the global cessation of dream reports, suggesting that these regions of the default mode network have key roles in the dreaming process (forebrain 'dream-on' hypothesis). To test this hypothesis, we measured regional cerebral blood flow (rCBF) using [(15)O]H2O positron emission tomography in healthy subjects with high and low dream recall frequencies (DRFs) during wakefulness (rest) and sleep (rapid eye movement (REM) sleep, N2, and N3). Compared with Low recallers (0.5 ± 0.3 dream recall per week in average), High recallers (5.2 ± 1.4) showed higher rCBF in the TPJ during REM sleep, N3, and wakefulness, and in the MPFC during REM sleep and wakefulness. We demonstrate that the resting states of High recallers and Low recallers differ during sleep and wakefulness. It coheres with previous ERP results and confirms that a high/low DRF is associated with a specific functional organization of the brain. These results support the forebrain 'dream-on' hypothesis and suggest that TPJ and MPFC are not only involved in dream recall during wakefulness but also have a role in dreaming during sleep (production and/or encoding). Increased activity in the TPJ and MPFC might promote the mental imagery and/or memory encoding of dreams. Notably, increased activity in TPJ might facilitate attention orienting toward external stimuli and promote intrasleep wakefulness, facilitating the encoding of the dreams in memory.

  12. Long-Term Fuid Flow Measurements From Widely Varied Oceanic Settings Elucidate Near-Surface Hydrologic Environments

    NASA Astrophysics Data System (ADS)

    Tryon, M. D.; Brown, K. M.

    2003-12-01

    The quantification of aqueous flux rates from various ocean floor environments has been a goal of numerous scientific programs for more than a decade with increasing focus on gas hydrate regions. Six years ago we developed the Chemical and Aqueous Transport (CAT) meter to collect long-term temporal records of low to moderate aqueous flow rates in sedimented ocean floor environments and, more specifically, to quantify to mass flux associated with the formation of gas hydrates. Since that time thirty of these instruments have been built and over a hundred deployments accomplished in a variety of hydrate and non-hydrate settings. We present here an overview of the results of these deployments and compare and contrast the flow records from these varied hydrological environments. Specific environments include: Gas Hydrates (Hydrate Ridge and the Eel River area on the Cascadia convergent margin, and Bush Hill in northern Gulf of Mexico), Hydrothermal (Japan's Sagami Bay and the incoming plate offshore Costa Rica's Nicoya Peninsula, TicoFlux area), and the tectonically active convergent margin off Nicoya and Osa. One of the most important outcomes of this research is the realization that fluid flow across the seabed/ocean interface is often dominated by shallow subsurface and oceanographic processes which vary significantly over time. These processes can be as simple as the diurnal pressure gradients caused by the rise and fall of tides to highly complex processes associated with the formation and transport of subsurface free gas. These processes have been both a boon and a bane to our research. Tidal oscillations have tended to mask the net flow in many very low flux settings. The high degree of spatial and temporal variation in some environments have revealed the extreme difficulty of quantifying the more widespread mass flux associated with the underlying tectonic processes. Yet, the nature of these variations have allowed us to better constrain the fundamental

  13. Nonlinearly Activated Neural Network for Solving Time-Varying Complex Sylvester Equation.

    PubMed

    Li, Shuai; Li, Yangming

    2013-10-28

    The Sylvester equation is often encountered in mathematics and control theory. For the general time-invariant Sylvester equation problem, which is defined in the domain of complex numbers, the Bartels-Stewart algorithm and its extensions are effective and widely used with an O(n³) time complexity. When applied to solving the time-varying Sylvester equation, the computation burden increases intensively with the decrease of sampling period and cannot satisfy continuous realtime calculation requirements. For the special case of the general Sylvester equation problem defined in the domain of real numbers, gradient-based recurrent neural networks are able to solve the time-varying Sylvester equation in real time, but there always exists an estimation error while a recently proposed recurrent neural network by Zhang et al [this type of neural network is called Zhang neural network (ZNN)] converges to the solution ideally. The advancements in complex-valued neural networks cast light to extend the existing real-valued ZNN for solving the time-varying real-valued Sylvester equation to its counterpart in the domain of complex numbers. In this paper, a complex-valued ZNN for solving the complex-valued Sylvester equation problem is investigated and the global convergence of the neural network is proven with the proposed nonlinear complex-valued activation functions. Moreover, a special type of activation function with a core function, called sign-bi-power function, is proven to enable the ZNN to converge in finite time, which further enhances its advantage in online processing. In this case, the upper bound of the convergence time is also derived analytically. Simulations are performed to evaluate and compare the performance of the neural network with different parameters and activation functions. Both theoretical analysis and numerical simulations validate the effectiveness of the proposed method.

  14. Teachers' Collaborative Activity in School-Wide Interventions

    ERIC Educational Resources Information Center

    Ertesvåg, Sigrun K.

    2014-01-01

    Despite the strong interest in research about collaboration among teachers, there are few longitudinal studies that have investigated improvements in collaborative activity among teachers through school-wide interventions. Drawing on data from a larger study, this article describes improvements in collaborative activity among 900 teachers at 28…

  15. Analyzing Age-Rotation-Activity Relationships in Wide Binary Systems

    NASA Astrophysics Data System (ADS)

    Walton Clarke, Riley; Davenport, James R. A.

    2017-01-01

    We present an analysis of flare activity among equal mass wide binary pairs using a combination of value-added data sets from the NASA Kepler mission. Wide binary twins form from the same molecular cloud and are therefore coeval, making them ideal benchmarks for stellar evolution and formation studies. This implies that their magnetic activity should decay at the same rate, causing a similar decrease in flare activity over time. The first data set is the list of known wide binary candidates in the Kepler field, and contains pairs of stars that have similar proper motions. We then crossmatch these systems with data on relative flare luminosity for ~200,000 stars in the original Kepler field, provided by an automated flare-finding algorithm. This combined data set allows us to compare flare activity, mass, and pair separation between stars in binary pairs. We preliminarily find that the flare rates for these stars do not show strong correlation, indicating either a large intrinsic scatter in the flare rate as these stars age, or that the formation mechanism of wide binaries somehow affects their dynamo evolution. As a goal for future development of this work, we hope to compare flare rates with gyrochronology in these key systems.

  16. Rooting depth and water source flexibility of Arundo donax across a wide and topographically varied floodplain inferred from stable isotopes

    NASA Astrophysics Data System (ADS)

    Moore, G. W.; West, J. B.; Li, F.; Kui, L.

    2011-12-01

    sources relative to groundwater. Rhizome water isotopic composition exhibited marked spatio-temporal variability that showed strong sensitivity to both soil moisture deficits and flooding. Our results demonstrate that Arundo readily switches water source from surface soil to groundwater to maintain relatively uniform transpiration across environmental gradients. Consistent with our observations of rooting depths to at least 5 m, dependence on groundwater increased with decreasing soil moisture in a similar manner across a wide range of groundwater depths (<1 m to 5 m), with no apparent influence of depth on deep water access. These trends illustrate how this now broadly-distributed species benefits from flexible use of hydrologic flowpaths unique to riparian environments. A more in-depth understanding of the ecohydrological interactions between the river, the hyporheic zone, riparian sediments and soils will improve our ability to predict ecosystem responses to changing climate and increasing human demands for water.

  17. Effect of varying accelerometry criteria on physical activity: the Look AHEAD Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The importance of physical activity in weight management is widely documented. Although accelerometers offer an objective measure of activity that provide a valuable tool for intervention research, considerations for processing these data need further development. Objective: This study tests the eff...

  18. New exponential synchronization criteria for time-varying delayed neural networks with discontinuous activations.

    PubMed

    Cai, Zuowei; Huang, Lihong; Zhang, Lingling

    2015-05-01

    This paper investigates the problem of exponential synchronization of time-varying delayed neural networks with discontinuous neuron activations. Under the extended Filippov differential inclusion framework, by designing discontinuous state-feedback controller and using some analytic techniques, new testable algebraic criteria are obtained to realize two different kinds of global exponential synchronization of the drive-response system. Moreover, we give the estimated rate of exponential synchronization which depends on the delays and system parameters. The obtained results extend some previous works on synchronization of delayed neural networks not only with continuous activations but also with discontinuous activations. Finally, numerical examples are provided to show the correctness of our analysis via computer simulations. Our method and theoretical results have a leading significance in the design of synchronized neural network circuits involving discontinuous factors and time-varying delays.

  19. The Influence of Epoch Length on Physical Activity Patterns Varies by Child's Activity Level

    ERIC Educational Resources Information Center

    Nettlefold, Lindsay; Naylor, P. J.; Warburton, Darren E. R.; Bredin, Shannon S. D.; Race, Douglas; McKay, Heather A.

    2016-01-01

    Purpose: Patterns of physical activity (PA) and sedentary time, including volume of bouted activity, are important health indicators. However, the effect of accelerometer epoch length on measurement of these patterns and associations with health outcomes in children remain unknown. Method: We measured activity patterns in 308 children (52% girls,…

  20. Quantifying Time-Varying Multiunit Neural Activity Using Entropy-Based Measures

    PubMed Central

    Choi, Young-Seok; Koenig, Matthew A.; Jia, Xiaofeng

    2011-01-01

    Modern microelectrode arrays make it possible to simultaneously record population neural activity. However, methods to analyze multiunit activity (MUA), which reflects the aggregate spiking activity of a population of neurons, have remained underdeveloped in comparison to those used for studying single unit activity (SUA). In scenarios where SUA is hard to record and maintain or is not representative of brain’s response, MUA is informative in deciphering the brain’s complex time-varying response to stimuli or to clinical insults. Here, we present two quantitative methods of analysis of the time-varying dynamics of MUA without spike detection. These methods are based on the multiresolution discrete wavelet transform (DWT) of an envelope of MUA (eMUA) followed by information theoretic measures: multiresolution entropy (MRE) and the multiresolution Kullback–Leibler distance (MRKLD).We test the proposed quantifiers on both simulated and experimental MUA recorded from rodent cortex in an experimental model of global hypoxic–ischemic brain injury. First, our results validate the use of the eMUA as an alternative to detecting and analyzing transient and complex spike activity. Second, the MRE and MRKLD are shown to respond to dynamic changes due to the brain’s response to global injury and to identify the transient changes in the MUA. PMID:20460201

  1. Reduced risk of breast cancer associated with recreational physical activity varies by HER2 status

    PubMed Central

    Ma, Huiyan; Xu, Xinxin; Ursin, Giske; Simon, Michael S; Marchbanks, Polly A; Malone, Kathleen E; Lu, Yani; McDonald, Jill A; Folger, Suzanne G; Weiss, Linda K; Sullivan-Halley, Jane; Deapen, Dennis M; Press, Michael F; Bernstein, Leslie

    2015-01-01

    Convincing epidemiologic evidence indicates that physical activity is inversely associated with breast cancer risk. Whether this association varies by the tumor protein expression status of the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), or p53 is unclear. We evaluated the effects of recreational physical activity on risk of invasive breast cancer classified by the four biomarkers, fitting multivariable unconditional logistic regression models to data from 1195 case and 2012 control participants in the population-based Women’s Contraceptive and Reproductive Experiences Study. Self-reported recreational physical activity at different life periods was measured as average annual metabolic equivalents of energy expenditure [MET]-hours per week. Our biomarker-specific analyses showed that lifetime recreational physical activity was negatively associated with the risks of ER-positive (ER+) and of HER2-negative (HER2−) subtypes (both Ptrend ≤ 0.04), but not with other subtypes (all Ptrend > 0.10). Analyses using combinations of biomarkers indicated that risk of invasive breast cancer varied only by HER2 status. Risk of HER2–breast cancer decreased with increasing number of MET-hours of recreational physical activity in each specific life period examined, although some trend tests were only marginally statistically significant (all Ptrend ≤ 0.06). The test for homogeneity of trends (HER2– vs. HER2+ ) reached statistical significance only when evaluating physical activity during the first 10 years after menarche (Phomogeneity = 0.03). Our data suggest that physical activity reduces risk of invasive breast cancers that lack HER2 overexpression, increasing our understanding of the biological mechanisms by which physical activity acts. PMID:25924995

  2. Reduced risk of breast cancer associated with recreational physical activity varies by HER2 status.

    PubMed

    Ma, Huiyan; Xu, Xinxin; Ursin, Giske; Simon, Michael S; Marchbanks, Polly A; Malone, Kathleen E; Lu, Yani; McDonald, Jill A; Folger, Suzanne G; Weiss, Linda K; Sullivan-Halley, Jane; Deapen, Dennis M; Press, Michael F; Bernstein, Leslie

    2015-07-01

    Convincing epidemiologic evidence indicates that physical activity is inversely associated with breast cancer risk. Whether this association varies by the tumor protein expression status of the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), or p53 is unclear. We evaluated the effects of recreational physical activity on risk of invasive breast cancer classified by the four biomarkers, fitting multivariable unconditional logistic regression models to data from 1195 case and 2012 control participants in the population-based Women's Contraceptive and Reproductive Experiences Study. Self-reported recreational physical activity at different life periods was measured as average annual metabolic equivalents of energy expenditure [MET]-hours per week. Our biomarker-specific analyses showed that lifetime recreational physical activity was negatively associated with the risks of ER-positive (ER+) and of HER2-negative (HER2-) subtypes (both Ptrend  ≤ 0.04), but not with other subtypes (all Ptrend  > 0.10). Analyses using combinations of biomarkers indicated that risk of invasive breast cancer varied only by HER2 status. Risk of HER2-breast cancer decreased with increasing number of MET-hours of recreational physical activity in each specific life period examined, although some trend tests were only marginally statistically significant (all Ptrend  ≤ 0.06). The test for homogeneity of trends (HER2- vs. HER2+ ) reached statistical significance only when evaluating physical activity during the first 10 years after menarche (Phomogeneity  = 0.03). Our data suggest that physical activity reduces risk of invasive breast cancers that lack HER2 overexpression, increasing our understanding of the biological mechanisms by which physical activity acts.

  3. AST: Activity-Security-Trust driven modeling of time varying networks

    PubMed Central

    Wang, Jian; Xu, Jiake; Liu, Yanheng; Deng, Weiwen

    2016-01-01

    Network modeling is a flexible mathematical structure that enables to identify statistical regularities and structural principles hidden in complex systems. The majority of recent driving forces in modeling complex networks are originated from activity, in which an activity potential of a time invariant function is introduced to identify agents’ interactions and to construct an activity-driven model. However, the new-emerging network evolutions are already deeply coupled with not only the explicit factors (e.g. activity) but also the implicit considerations (e.g. security and trust), so more intrinsic driving forces behind should be integrated into the modeling of time varying networks. The agents undoubtedly seek to build a time-dependent trade-off among activity, security, and trust in generating a new connection to another. Thus, we reasonably propose the Activity-Security-Trust (AST) driven model through synthetically considering the explicit and implicit driving forces (e.g. activity, security, and trust) underlying the decision process. AST-driven model facilitates to more accurately capture highly dynamical network behaviors and figure out the complex evolution process, allowing a profound understanding of the effects of security and trust in driving network evolution, and improving the biases induced by only involving activity representations in analyzing the dynamical processes. PMID:26888717

  4. AST: Activity-Security-Trust driven modeling of time varying networks.

    PubMed

    Wang, Jian; Xu, Jiake; Liu, Yanheng; Deng, Weiwen

    2016-02-18

    Network modeling is a flexible mathematical structure that enables to identify statistical regularities and structural principles hidden in complex systems. The majority of recent driving forces in modeling complex networks are originated from activity, in which an activity potential of a time invariant function is introduced to identify agents' interactions and to construct an activity-driven model. However, the new-emerging network evolutions are already deeply coupled with not only the explicit factors (e.g. activity) but also the implicit considerations (e.g. security and trust), so more intrinsic driving forces behind should be integrated into the modeling of time varying networks. The agents undoubtedly seek to build a time-dependent trade-off among activity, security, and trust in generating a new connection to another. Thus, we reasonably propose the Activity-Security-Trust (AST) driven model through synthetically considering the explicit and implicit driving forces (e.g. activity, security, and trust) underlying the decision process. AST-driven model facilitates to more accurately capture highly dynamical network behaviors and figure out the complex evolution process, allowing a profound understanding of the effects of security and trust in driving network evolution, and improving the biases induced by only involving activity representations in analyzing the dynamical processes.

  5. AST: Activity-Security-Trust driven modeling of time varying networks

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Xu, Jiake; Liu, Yanheng; Deng, Weiwen

    2016-02-01

    Network modeling is a flexible mathematical structure that enables to identify statistical regularities and structural principles hidden in complex systems. The majority of recent driving forces in modeling complex networks are originated from activity, in which an activity potential of a time invariant function is introduced to identify agents’ interactions and to construct an activity-driven model. However, the new-emerging network evolutions are already deeply coupled with not only the explicit factors (e.g. activity) but also the implicit considerations (e.g. security and trust), so more intrinsic driving forces behind should be integrated into the modeling of time varying networks. The agents undoubtedly seek to build a time-dependent trade-off among activity, security, and trust in generating a new connection to another. Thus, we reasonably propose the Activity-Security-Trust (AST) driven model through synthetically considering the explicit and implicit driving forces (e.g. activity, security, and trust) underlying the decision process. AST-driven model facilitates to more accurately capture highly dynamical network behaviors and figure out the complex evolution process, allowing a profound understanding of the effects of security and trust in driving network evolution, and improving the biases induced by only involving activity representations in analyzing the dynamical processes.

  6. Nonlinear parametrically excited vibration and active control of gear pair system with time-varying characteristic

    NASA Astrophysics Data System (ADS)

    Liu, Shuang; Wang, Jin-Jin; Liu, Jin-Jie; Li, Ya-Qian

    2015-10-01

    In the present work, we investigate the nonlinear parametrically excited vibration and active control of a gear pair system involving backlash, time-varying meshing stiffness and static transmission error. Firstly, a gear pair model is established in a strongly nonlinear form, and its nonlinear vibration characteristics are systematically investigated through different approaches. Several complicated phenomena such as period doubling bifurcation, anti period doubling bifurcation and chaos can be observed under the internal parametric excitation. Then, an active compensation controller is designed to suppress the vibration, including the chaos. Finally, the effectiveness of the proposed controller is verified numerically. Project supported by the National Natural Science Foundation of China (Grant No. 61104040), the Natural Science Foundation of Hebei Province, China (Grant No. E2012203090), and the University Innovation Team of Hebei Province Leading Talent Cultivation Project, China (Grant No. LJRC013).

  7. Effect of Varying Accelerometry Criteria on Physical Activity: The Look AHEAD Study

    PubMed Central

    Miller, G. D.; Jakicic, J. M.; Rejeski, W. J.; Whit-Glover, M.; Lang, W.; Walkup, M. P.; Hodges, M.

    2012-01-01

    The importance of physical activity in weight management is widely documented. Although accelerometers offer an objective measure of activity that provide a valuable tool for intervention research, considerations for processing these data need further development. This study tests the effects of using different criteria for accelerometry data reduction. Data were obtained from 2,240 overweight and obese individuals with type 2 diabetes mellitus (T2DM) from the Look AHEAD study, with 2,177 baseline accelerometer files used for analysis. Number, duration, and intensity of moderate (≥3 METS) and vigorous (≥6 METS) activity bouts were compared using various data reduction criteria. Daily wear time was identified as 1,440 minutes per day minus non-wear time. Comparisons of physical activity patterns for non-wear time (using either 20, 30 or 60 minutes of continuous zeros), minimal daily wear time (8, 10, and 12 hours), number of days with available data (4, 5, and 6 days), weekdays versus weekends, and one- or two-minute time interruptions in an activity bout were performed. In this mostly obese population with T2DM (BMI = 36.4 kg/m2; mean age = 59.0 y), there were minimal differences in physical activity patterns using the different methods of data reduction. Altering criteria led to differences in the number of available data (sample size) meeting specific criteria. Although our results are likely directly applicable only to obese individuals with T2DM, an understudied population with regards to physical activity, the systematic analysis for data reduction employed can be more generalizable and provide guidance in this area in the absence of standard procedures. PMID:23505166

  8. Flatness-based active disturbance rejection control for linear systems with unknown time-varying coefficients

    NASA Astrophysics Data System (ADS)

    Huang, Congzhi; Sira-Ramírez, Hebertt

    2015-12-01

    A flatness-based active disturbance rejection control approach is proposed to deal with the linear systems with unknown time-varying coefficients and external disturbances. By selecting appropriate nominal values for the parameters of the system, all the deviation between the nominal and actual dynamics of the controlled process, as well as all the external disturbances can be viewed as a total disturbance. Based on the accurately estimated total disturbance with the aid of the proposed extended state observer, a linear proportional derivative feedback control law taking into account the derivatives of the desired output is designed to eliminate the effect of the total disturbance on the system performance. Finally, the load frequency control problem of a single-area power system with non-reheated unit is employed as an illustrative example to demonstrate the effectiveness of the proposed approach.

  9. 15 CFR 922.163 - Prohibited activities-Sanctuary-wide.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., injury to, or possession of coral or live rock. (i) Moving, removing, taking, harvesting, damaging...) any living or dead coral, or coral formation, or attempting any of these activities, except as... in such a manner as to strike or otherwise injure coral, seagrass, or any other immobile...

  10. Controlling the antibacterial activity of CuSn thin films by varying the contents of Sn

    NASA Astrophysics Data System (ADS)

    Kang, Yujin; Park, Juyun; Kim, Dong-Woo; Kim, Hakjun; Kang, Yong-Cheol

    2016-12-01

    We investigated antibacterial activity of CuSn thin films against Gram positive Staphylococcus aureus (S. aureus). CuSn thin films with different Cu to Sn ratios were deposited on Si(100) by radio frequency (RF) magnetron sputtering method using Cu and Sn metal anodes. The film thickness was fixed at 200 nm by varying the sputtering time and RF power on the metal targets. The antibacterial test was conducted in various conditions such as different contact times and Cu to Sn ratios in the CuSn films. The antibacterial activities of CuSn thin films increased as the ratio of Cu and the contact time between the film and bacteria suspension increased execpt in the case of CuSn-83. The oxidation states of Cu and Sn and the chemical composition of CuSn thin films before and after the antibacterial test were investigated by X-ray photoelectron spectroscopy (XPS). When the contact time was fixed, the Cu species was further oxidized as the RF power on Cu target increased. The intensity of Sn 3d decreased with increasing Cu ratio. When the sample was fixed, the peak intensity of Sn 3d decreased as the contact time increased due to the permeation of Sn into the cell.

  11. Brain regional networks active during the mismatch negativity vary with paradigm.

    PubMed

    MacLean, Shannon E; Blundon, Elizabeth G; Ward, Lawrence M

    2015-08-01

    We used independent component analysis (ICA) of high-density EEG recordings coupled with single dipole fitting to identify the dominant brain regions active during the MMN in two different versions of a passive oddball paradigm: a simple, monotic, frequency-deviant paradigm and a more complex, dichotic, frequency-deviant paradigm with deviants occurring in either ear alone or in both ears at the same time. In both paradigms we found brain regional sources in the temporal and frontal cortices active during the MMN period, consistent with some previous studies. In the simpler paradigm, the scalp-potential variance during the earlier (70-120 ms) MMN was mostly accounted for by a wide array of temporal, frontal, and parietal sources. In the more complex paradigm, however, a generator in the prefrontal cortex accounted for a substantial amount of the variance of the scalp potential during the somewhat later MMN period (120-200 ms). These findings are consistent with a more nuanced view of the MMN and its generators than has been held in the past.

  12. DNA-directed alkylating agents. 3. Structure-activity relationships for acridine-linked aniline mustards: consequences of varying the length of the linker chain.

    PubMed

    Valu, K K; Gourdie, T A; Boritzki, T J; Gravatt, G L; Baguley, B C; Wilson, W R; Wakelin, L P; Woodgate, P D; Denny, W A

    1990-11-01

    Four series of acridine-linked aniline mustards have been prepared and evaluated for in vitro cytotoxicity, in vivo antitumor activity, and DNA cross-linking ability. The anilines were attached to the DNA-intercalating acridine chromophores by link groups (-O-, -CH2-, -S-, and -SO2-) of widely varying electronic properties, providing four series of widely differing mustard reactivity where the alkyl chain linking the acridine and mustard moieties was varied from two to five carbons. Relationships were sought between chain length and biological properties. Within each series, increasing the chain length did not alter the reactivity of the alkylating moiety but did appear to position it differently on the DNA, since cross-linking ability (measured by agarose gel assay) altered with chain length, being maximal with the C4 analogue. The in vivo antitumor activities of the compounds depended to some extent on the reactivity of the mustard, with the least reactive SO2 compounds being inactive. However, DNA-targeting did appear to allow the use of less reactive mustards, since the S-linked acridine mustards showed significant activity whereas the parent S-mustard did not. Within each active series, the most active compound was the C4 homologue, suggesting some relationship between activity and extent of DNA alkylation.

  13. The magnitudes of hyperpolarization-activated and low-voltage-activated potassium currents co-vary in neurons of the ventral cochlear nucleus.

    PubMed

    Cao, Xiao-Jie; Oertel, Donata

    2011-08-01

    In the ventral cochlear nucleus (VCN), neurons have hyperpolarization-activated conductances, which in some cells are enormous, that contribute to the ability of neurons to convey acoustic information in the timing of their firing by decreasing the input resistance and speeding-up voltage changes. Comparisons of the electrophysiological properties of neurons in the VCN of mutant mice that lack the hyperpolarization-activated cyclic nucleotide-gated channel α subunit 1 (HCN1(-/-)) (Nolan et al. 2003) with wild-type controls (HCN1(+/+)) and with outbred ICR mice reveal that octopus, T stellate, and bushy cells maintain their electrophysiological distinctions in all strains. Hyperpolarization-activated (I(h)) currents were smaller and slower, input resistances were higher, and membrane time constants were longer in HCN1(-/-) than in HCN1(+/+) in octopus, bushy, and T stellate cells. There were significant differences in the average magnitudes of I(h), input resistances, and time constants between HCN1(+/+) and ICR mice, but the resting potentials did not differ between strains. I(h) is opposed by a low-voltage-activated potassium (I(KL)) current in bushy and octopus cells, whose magnitudes varied widely between neuronal types and between strains. The magnitudes of I(h) and I(KL) were correlated across neuronal types and across mouse strains. Furthermore, these currents balanced one another at the resting potential in individual cells. The magnitude of I(h) and I(KL) is linked in bushy and octopus cells and varies not only between HCN1(-/-) and HCN1(+/+) but also between "wild-type" strains of mice, raising the question to what extent the wild-type strains reflect normal mice.

  14. The magnitudes of hyperpolarization-activated and low-voltage-activated potassium currents co-vary in neurons of the ventral cochlear nucleus

    PubMed Central

    Cao, Xiao-Jie

    2011-01-01

    In the ventral cochlear nucleus (VCN), neurons have hyperpolarization-activated conductances, which in some cells are enormous, that contribute to the ability of neurons to convey acoustic information in the timing of their firing by decreasing the input resistance and speeding-up voltage changes. Comparisons of the electrophysiological properties of neurons in the VCN of mutant mice that lack the hyperpolarization-activated cyclic nucleotide-gated channel α subunit 1 (HCN1−/−) (Nolan et al. 2003) with wild-type controls (HCN1+/+) and with outbred ICR mice reveal that octopus, T stellate, and bushy cells maintain their electrophysiological distinctions in all strains. Hyperpolarization-activated (Ih) currents were smaller and slower, input resistances were higher, and membrane time constants were longer in HCN1−/− than in HCN1+/+ in octopus, bushy, and T stellate cells. There were significant differences in the average magnitudes of Ih, input resistances, and time constants between HCN1+/+ and ICR mice, but the resting potentials did not differ between strains. Ih is opposed by a low-voltage-activated potassium (IKL) current in bushy and octopus cells, whose magnitudes varied widely between neuronal types and between strains. The magnitudes of Ih and IKL were correlated across neuronal types and across mouse strains. Furthermore, these currents balanced one another at the resting potential in individual cells. The magnitude of Ih and IKL is linked in bushy and octopus cells and varies not only between HCN1−/− and HCN1+/+ but also between “wild-type” strains of mice, raising the question to what extent the wild-type strains reflect normal mice. PMID:21562186

  15. EMG Activity of Selected Trunk and Hip Muscles During a Squat Lift: Effect of Varying the Lumbar Posture

    DTIC Science & Technology

    1990-01-01

    DIXC hLE O.. 1990 Thesis/i " EMG Activity of Selected Trunk and Hip Muscles During a Squat Lift: Effect of Varying the Lumbar Posture N Jim Vakos...1990 01-1’ ABSTRACT OF THESIS EMG ACTIVITY OF SELECTED TRUNK AND HIP MUSCLES DURING A SQUAT LIFT: EFFECT OF VARYING THE LUMBAR POSTURE - The...electromyographic ( EMG ) activity of selected hip and trunk muscles was recorded during a squat lift and the effects of two different lumbar spine postures were

  16. A new iterative linear integral isoconversional method for the determination of the activation energy varying with the conversion degree.

    PubMed

    Cai, Junmeng; Chen, Siyu

    2009-10-01

    The conventional linear integral isoconversional methods may lead to important errors in the determination of the activation energy when the significant variation of the activation energy with the conversion degree occurs. Vyazovkin proposed an advanced nonlinear isoconversional method, which allows the activation energy to be accurately determined [Vyazovkin, J Comput Chem 2001, 22, 178]. However, the use of the Vyazovkin method raises the problem of the time-consuming minimization without derivatives. A new iterative linear integral isoconversional method for the determination of the activation energy as a function of the conversion degree has been proposed, which is capable of providing valid values of the activation energy even if the latter strongly varies with the conversion degree. Also, the new method leads to the correct values of the activation energy in much less time than the Vyazovkin method. The application of the new method is illustrated by processing of theoretically simulated data of a strongly varying activation energy process.

  17. Brief wide-field photostimuli evoke and modulate oscillatory reverberating activity in cortical networks

    PubMed Central

    Pulizzi, Rocco; Musumeci, Gabriele; Van den Haute, Chris; Van De Vijver, Sebastiaan; Baekelandt, Veerle; Giugliano, Michele

    2016-01-01

    Cell assemblies manipulation by optogenetics is pivotal to advance neuroscience and neuroengineering. In in vivo applications, photostimulation often broadly addresses a population of cells simultaneously, leading to feed-forward and to reverberating responses in recurrent microcircuits. The former arise from direct activation of targets downstream, and are straightforward to interpret. The latter are consequence of feedback connectivity and may reflect a variety of time-scales and complex dynamical properties. We investigated wide-field photostimulation in cortical networks in vitro, employing substrate-integrated microelectrode arrays and long-term cultured neuronal networks. We characterized the effect of brief light pulses, while restricting the expression of channelrhodopsin to principal neurons. We evoked robust reverberating responses, oscillating in the physiological gamma frequency range, and found that such a frequency could be reliably manipulated varying the light pulse duration, not its intensity. By pharmacology, mathematical modelling, and intracellular recordings, we conclude that gamma oscillations likely emerge as in vivo from the excitatory-inhibitory interplay and that, unexpectedly, the light stimuli transiently facilitate excitatory synaptic transmission. Of relevance for in vitro models of (dys)functional cortical microcircuitry and in vivo manipulations of cell assemblies, we give for the first time evidence of network-level consequences of the alteration of synaptic physiology by optogenetics. PMID:27099182

  18. 77 FR 64382 - Agency Information Collection (Nation-Wide Customer Satisfaction Surveys) Activities Under OMB...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF VETERANS AFFAIRS Agency Information Collection (Nation-Wide Customer Satisfaction Surveys) Activities Under OMB....'' SUPPLEMENTARY INFORMATION: Title: Nation-wide Customer Satisfaction Surveys, VA Forms 10-1465- 2 through...

  19. 75 FR 25320 - Agency Information Collection (Nation-wide Customer Satisfaction Surveys) Activities Under OMB...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF VETERANS AFFAIRS Agency Information Collection (Nation-wide Customer Satisfaction Surveys) Activities Under OMB... INFORMATION: Title: Nation-wide Customer Satisfaction Surveys, VA Forms 1465-2 through 1465-4. OMB...

  20. 75 FR 9277 - Proposed Information Collection (Nation-Wide Customer Satisfaction Surveys) Activity: Comment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF VETERANS AFFAIRS Proposed Information Collection (Nation-Wide Customer Satisfaction Surveys) Activity: Comment.... Title: Nation-wide Customer Satisfaction Surveys, VA Forms 1465-2 through 1465-4. OMB Control...

  1. 77 FR 2349 - Proposed Information Collection (Nation-wide Customer Satisfaction Surveys) Activity: Comment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF VETERANS AFFAIRS Proposed Information Collection (Nation-wide Customer Satisfaction Surveys) Activity: Comment... forms of information technology. Title: Nation-wide Customer Satisfaction Surveys, VA Forms 10-1465-...

  2. Use of a lag differential reinforcement contingency to increase varied selections of classroom activities.

    PubMed

    Cammilleri, Anthony P; Hanley, Gregory P

    2005-01-01

    The present study evaluated the effects of a lag differential reinforcement contingency on 2 students' activity selections using reversal designs. Results showed that the lag contingency was responsible for promoting increased novel selections, engagement in diverse activities, and greater progress with respect to programmed academic activities.

  3. Use of a Lag Differential Reinforcement Contingency to Increase Varied Selections of Classroom Activities

    ERIC Educational Resources Information Center

    Cammilleri, Anthony P.; Hanley, Gregory P.

    2005-01-01

    The present study evaluated the effects of a lag differential reinforcement contingency on 2 students' activity selections using reversal designs. Results showed that the lag contingency was responsible for promoting increased novel selections, engagement in diverse activities, and greater progress with respect to programmed academic activities.

  4. A Comparison of Attitudes and Exercise Habits of Alumni from Colleges with Varying Degrees of Physical Education Activity Programs.

    ERIC Educational Resources Information Center

    Adams, Thomas M.; Brynteson, Paul

    1992-01-01

    Study compared the exercise attitudes and habits of alumni from four colleges with varying physical education activity (PEA) requirements. Survey results indicated the type of PEA programs offered influenced alumni attitudes toward fitness and exercise behaviors. Students from colleges with higher PEA requirements had more positive exercise…

  5. DNA-directed alkylating agents. 1. Structure-activity relationships for acridine-linked aniline mustards: consequences of varying the reactivity of the mustard.

    PubMed

    Gourdie, T A; Valu, K K; Gravatt, G L; Boritzki, T J; Baguley, B C; Wakelin, L P; Wilson, W R; Woodgate, P D; Denny, W A

    1990-04-01

    A series of DNA-targeted aniline mustards have been prepared, and their chemical reactivity and in vitro and in vivo cytotoxicity have been evaluated and compared with that of the corresponding simple aniline mustards. The alkylating groups were anchored to the DNA-intercalating 9-aminoacridine chromophore by an alkyl chain of fixed length attached at the mustard 4-position through a link group X, while the corresponding simple mustards possessed an electronically identical small group at this position. The link group was varied to provide a series of compounds of similar geometry but widely differing mustard reactivity. Variation in biological activity should then largely be a consequence of this varying reactivity. Rates of mustard hydrolysis in the two series related only to the electronic properties of the link group, with attachment of the intercalating chromophore having no effect. The cytotoxicities of the simple mustards correlated well with group electronic properties (with a 200-300-fold range in IC50S). The corresponding DNA-targeted mustards were much more potent (up to 100-fold), but their IC50 values varied much less with linker group electronic properties. Most of the DNA-targeted mustards showed in vivo antitumor activity, being both more active and more dose-potent than either the corresponding untargeted mustards and chlorambucil. These results show that targeting alkylating agents to DNA by attachment to DNA-affinic units may be a useful strategy.

  6. Biodegradation of an Organophosphate Chemical Warfare Agent Simulant by Activated Sludge with Varying Solid Retention Times

    DTIC Science & Technology

    2013-03-21

    coefficient close to that of VX, which may yield similar sorption kinetics between the two. Walters (2013) found that sorption of malathion to the activated...weapons in the activated sludge or under what conditions this removal is optimal. This study examined the fate of malathion , a surrogate compound for...activated sludge process in wastewater treatment facilities. Results show that a constant influent of malathion will be removed from the effluent

  7. Effectiveness of Albendazole for Hookworm Varies Widely by Community and Correlates with Nutritional Factors: A Cross-Sectional Study of School-Age Children in Ghana.

    PubMed

    Humphries, Debbie; Nguyen, Sara; Kumar, Sunny; Quagraine, Josephine E; Otchere, Joseph; Harrison, Lisa M; Wilson, Michael; Cappello, Michael

    2017-02-08

    Mass drug administration (MDA) targeting school-age children is recommended by the World Health Organization for the global control of soil-transmitted helminth (STH) infections. Although considered safe and cost-effective to deliver, benzimidazole anthelminthics are variably effective against the three most common STHs, and widespread use has raised concern about the potential for emerging resistance. To identify factors mediating response to albendazole, we conducted a cross-sectional study of hookworm infection in the Kintampo North Municipality of Ghana in 2011. Among 140 school-age children residing in five contiguous communities, the hookworm prevalence was 59% (82/140). The overall cure rate following administration of single-dose albendazole (400 mg) was 35% (27/76), with a community-wide fecal egg reduction rate (ERR) of 61% (95% confidence interval: 51.8-71.1). Significant disparities were observed in albendazole effectiveness by community, with a cure rate as low as 0% (N = 24) in Jato Akuraa and ERRs ranging from 53% to 95% across the five study sites. Individual host factors associated with response to deworming treatment included time since last meal, pretreatment blood hemoglobin level, and mid-upper arm circumference. These data demonstrate significant community-level variation in the effectiveness of albendazole, even among populations living in close proximity. Identification of host factors that influence response to albendazole, most notably the timing of drug administration and nutritional factors, creates an opportunity to enhance the effectiveness of deworming through targeted interventions. These findings also demonstrate the importance of measuring anthelminthic response as part of the monitoring and evaluation of community-based deworming programs.

  8. Enzymatic activity of a mine soil varies according to vegetation cover and level of compost applied.

    PubMed

    de Varennes, Amerilis; Abreu, Maria Manuela; Qu, Guiwei; Cunha-Queda, Cristina

    2010-01-01

    We applied three doses of compost from mixed municipal solid waste (0, 15, and 30 g kg(-1) of soil) to a soil developed on pyrite mine wastes. Part of the soil was planted with young Erica australis L. collected at the mine; part was fertilized with N-P-K-Mg and sown with Dactylis glomerata L .Bare soil without mineral fertilization was included in the experiment, as well. Compost application to bare soil increased pH, provided plant nutrients, and enhanced the activity of the six soil enzymes tested. Growth of D. glomerata, and E. australis was stimulated in compost-amended soil compared with unamended controls. The presence of D. glomerata led to the greatest activities of soil acid phosphatase, beta-glucosidase, and cellulase compared with bare soil or with soil with E. australis. The presence of E. australis increased the activities of protease and cellulase in amended soil, compared with control, but it impaired dehydrogenase, fl-glucosidase, and acid phosphatase activities. These negative impacts probably derived from phenolic compounds known to be released from roots of this species. The survival strategy of this species seems to include a small need for P in the shoots, and the release of exudates that impair microbial activity and P cycling.

  9. Effects of activated sludge on the degradation of chlorate in soils under varying environmental conditions.

    PubMed

    Jiang, Chunxiao; Li, Huashou; Lin, Chuxia

    2009-03-15

    Incubation experiments were conducted to examine the effects of activated sludge on degradation of chlorate in soils. The results show that application of activated sludge could significantly promote the decomposition of soil chlorate though the degradation rate of chlorate did not necessarily increase with increasing application rate of the sludge. The effectiveness of activated sludge on soil chlorate degradation was significantly affected by temperature, moisture content and pH. There is a tendency that the rate of chlorate decomposition increased with increasing temperature and moisture content until optimal values of temperature and moisture content were reached. This can be attributed to the enhanced activity of chlorate-reducing microorganisms in hot and more reducing soil conditions. Soil pH also had important controls on the decomposition of chlorate. The experimental results demonstrate that neutral pH more favoured the degradation of soil chlorate, compared to either acidic or alkaline pH. While soil organic matter content could affect chlorate decomposition, its impact on the effectiveness of activated sludge on chlorate degradation was minor. This study has implications for developing cost-effective techniques for remediating chlorate-contaminated soils, particularly in the longan-producing countries.

  10. Music Activity Reports by Music Teachers with Varying Training in Orff Schulwerk

    ERIC Educational Resources Information Center

    Sogin, David W.; Wang, Cecilia Chu

    2008-01-01

    The purpose of this study was to examine music activities occurring in the music classroom of teachers who received different levels of training in Orff Schulwerk. The subjects (N = 49) were teachers participating in three training levels at a summer Orff Schulwerk certification program in a university in the USA. Teachers were asked to report the…

  11. The Engagement in Musical Activities of Young Children with Varied Hearing Abilities

    ERIC Educational Resources Information Center

    Chen-Hafteck, Lily; Schraer-Joiner, Lyn

    2011-01-01

    This multiple case study examined the musical experiences of five hard-of-hearing/deaf children (hearing loss ranging from 35-95 dB) and four typical-hearing children, ages 3-4. Their responses to various musical activities were observed and analysed using flow indicators. It was found that both groups of children: (1) were capable of engaging in…

  12. Effects of Varying Team Sizes on Physical Activity Levels of College Students

    ERIC Educational Resources Information Center

    Gaudreault, Karen Lux; Cluphf, David; Russell, Jared; Lecheminant, James

    2014-01-01

    The purpose of this exploratory study was to examine physical activity levels among various team sizes for basketball and soccer in a C/UIPAP setting. Twenty-eight university physical education majors participated in the study. Participants engaged in three-on-three and five-on-five basketball and five-on-five and 11-on-11 soccer games. All games…

  13. Cutaneous immune activity varies with physiological state in female house sparrows (Passer domesticus).

    PubMed

    Martin, L B; Han, P; Kwong, J; Hau, M

    2006-01-01

    Many vertebrates show seasonality in immune defenses, perhaps because of trade-offs with other physiological processes. Trade-offs between reproduction and immune function have been well studied, but how other life cycle events such as molt affect immune function remains unclear. Here, we hypothesize that one possible explanation is that accumulative dissociated processes (e.g., resource deficits generated over the long term by physiological processes) can have delayed effects on immune activity. To test this hypothesis, we compared cutaneous immune responses in groups of captive female house sparrows (Passer domesticus) photoperiodically induced into six different life cycle stages. We predicted that if delayed trade-offs occur, immune activity would be reduced after a mature life state was reached (e.g., postmolt) and not just compromised when other tissues were actively growing (instantaneous trade-off). We found evidence for both types of trade-offs: immune responses were weakest in sparrows that had just completed postnuptial molt, but they were also weak in birds growing reproductive tissues or feathers. Birds in mature reproductive states or light molt had strong immune responses comparable with birds in a nonbreeding/nonmolting state. Altogether, our results indicate that immune activity in female house sparrows can be influenced by both instantaneous and delayed trade-offs.

  14. Varying responses of vegetation activity to climate changes on the Tibetan Plateau grassland.

    PubMed

    Cong, Nan; Shen, Miaogen; Yang, Wei; Yang, Zhiyong; Zhang, Gengxin; Piao, Shilong

    2017-02-28

    Vegetation activity on the Tibetan Plateau grassland has been substantially enhanced as a result of climate change, as revealed by satellite observations of vegetation greenness (i.e., the normalized difference vegetation index, NDVI). However, little is known about the temporal variations in the relationships between NDVI and temperature and precipitation, and understanding this is essential for predicting how future climate change would affect vegetation activity. Using NDVI data and meteorological records from 1982 to 2011, we found that the inter-annual partial correlation coefficient between growing season (May-September) NDVI and temperature (RNDVI-T) in a 15-year moving window for alpine meadow showed little change, likely caused by the increasing RNDVI-T in spring (May-June) and autumn (September) and decreasing RNDVI-T in summer (July-August). Growing season RNDVI-T for alpine steppe increased slightly, mainly due to increasing RNDVI-T in spring and autumn. The partial correlation coefficient between growing season NDVI and precipitation (RNDVI-P) for alpine meadow increased slightly, mainly in spring and summer, and RNDVI-P for alpine steppe increased, mainly in spring. Moreover, RNDVI-T for the growing season was significantly higher in those 15-year windows with more precipitation for alpine steppe. RNDVI-P for the growing season was significantly higher in those 15-year windows with higher temperature, and this tendency was stronger for alpine meadow than for alpine steppe. These results indicate that the impact of warming on vegetation activity of Tibetan Plateau grassland is more positive (or less negative) during periods with more precipitation and that the impact of increasing precipitation is more positive (or less negative) during periods with higher temperature. Such positive effects of the interactions between temperature and precipitation indicate that the projected warmer and wetter future climate will enhance vegetation activity of Tibetan

  15. Varying responses of vegetation activity to climate changes on the Tibetan Plateau grassland

    NASA Astrophysics Data System (ADS)

    Cong, Nan; Shen, Miaogen; Yang, Wei; Yang, Zhiyong; Zhang, Gengxin; Piao, Shilong

    2017-02-01

    Vegetation activity on the Tibetan Plateau grassland has been substantially enhanced as a result of climate change, as revealed by satellite observations of vegetation greenness (i.e., the normalized difference vegetation index, NDVI). However, little is known about the temporal variations in the relationships between NDVI and temperature and precipitation, and understanding this is essential for predicting how future climate change would affect vegetation activity. Using NDVI data and meteorological records from 1982 to 2011, we found that the inter-annual partial correlation coefficient between growing season (May-September) NDVI and temperature (RNDVI-T) in a 15-year moving window for alpine meadow showed little change, likely caused by the increasing RNDVI-T in spring (May-June) and autumn (September) and decreasing RNDVI-T in summer (July-August). Growing season RNDVI-T for alpine steppe increased slightly, mainly due to increasing RNDVI-T in spring and autumn. The partial correlation coefficient between growing season NDVI and precipitation (RNDVI-P) for alpine meadow increased slightly, mainly in spring and summer, and RNDVI-P for alpine steppe increased, mainly in spring. Moreover, RNDVI-T for the growing season was significantly higher in those 15-year windows with more precipitation for alpine steppe. RNDVI-P for the growing season was significantly higher in those 15-year windows with higher temperature, and this tendency was stronger for alpine meadow than for alpine steppe. These results indicate that the impact of warming on vegetation activity of Tibetan Plateau grassland is more positive (or less negative) during periods with more precipitation and that the impact of increasing precipitation is more positive (or less negative) during periods with higher temperature. Such positive effects of the interactions between temperature and precipitation indicate that the projected warmer and wetter future climate will enhance vegetation activity of Tibetan

  16. Alteration and modulation of protein activity by varying post-translational modification

    DOEpatents

    Thompson, David N; Reed, David W; Thompson, Vicki S; Lacey, Jeffrey A; Apel, William A

    2015-03-03

    Embodiments of the invention include methods of altering the enzymatic activity or solubility of an extremophilic enzyme or post-translationally modifying a protein of interest via using isolated or partially purified glycosyltransferases and/or post-translational modification proteins, extracts of cells comprising glycosyltransferases and/or post-translational modification proteins, and/or in cells comprising one or more glycosyltransferases and/or post-translational modification proteins.

  17. Alteration and modulation of protein activity by varying post-translational modification

    DOEpatents

    Thompson, David N.; Reed, David W.; Thompson, Vicki S.; Lacey, Jeffrey A.; Apel, William A.

    2016-07-12

    Embodiments of the invention include methods of altering the enzymatic activity or solubility of an extremophilic enzyme or post-translationally modifying a protein of interest via using isolated or partially purified glycosyltransferases and/or post-translational modification proteins, extracts of cells comprising glycosyltransferases and/or post-translational modification proteins, and/or in cells comprising one or more glycosyltransferases and/or post-translational modification proteins.

  18. PCB concentrations and activity of sea lamprey Petromyzon marinus vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Johnson, Nicholas S.; Binder, Thomas R.; Rediske, Richard R.; O'Keefe, James P.

    2013-01-01

    We determined the polychlorinated biphenyl (PCB) concentrations of 40 male and 40 female adult sea lampreys Petromyzon marinus captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, we performed a laboratory experiment using passive integrated transponder tags to determine whether male adult sea lampreys were more active than female adult sea lampreys. Sex had a significant effect on PCB concentration, and PCB concentration at a given level of sea lamprey condition was approximately 25 % greater in males than in females. Adjusting for the difference in condition between the sexes, males averaged a 17 % greater PCB concentration compared with females. Results from the laboratory experiment indicated that males were significantly more active than females. The observed sex difference in PCB concentrations was not due to female sea lampreys releasing eggs at spawning because the sea lamprey is semelparous, and we caught the sea lampreys before spawning. Rather, we attributed the sex difference in PCB concentrations to a greater rate of energy expenditure in males compared with females. We proposed that this greater rate of energy expenditure was likely due to greater activity. Our laboratory experiment results supported this hypothesis. A greater resting metabolic rate may also have contributed to a greater rate of energy expenditure. Our findings should eventually be applicable toward improving control of sea lamprey, a pest responsible for considerable damage to fisheries in lakes where it is not native.

  19. Sexual Harassment in the Active-Duty Navy: Findings from the 1991 Navy-Wide Survey

    DTIC Science & Technology

    1993-12-01

    NPRDC-TR-94-2) harassed. This direct query method has the advantage of recognizing the complexities involved in deciding whether sexually - oriented ...NPRDC-TR-94-2 December 13 Sexual Harassment in the Active-Duty Navy: Findings from the 1991 Navy-Wide Survey ɘ DTIC Authors ELECTE Amy L Culbertson...1991-1992 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Sexual Harassment in the Active-Duty Navy: N0002293WREE500 Findings from the 1991 Navy-Wide Survey 6

  20. Physical activity, subjective sleep quality and time in bed do not vary by moon phase in German adolescents.

    PubMed

    Smith, Maia P; Standl, Marie; Schulz, Holger; Heinrich, Joachim

    2016-12-08

    Lunar periodicity in human biology and behaviour, particularly sleep, has been reported. However, estimated relationships vary in direction (more or less sleep with full moon) if they exist at all, and studies tend to be so small that there is potential for confounding by weekly or monthly cycles. Lunar variation in physical activity has been posited as a driver of this relationship, but is likewise not well studied. We explore the association between lunar cycle, sleep and physical activity in a population-based sample of 1411 Germans age 14-17 years (46% male). Physical activity (daily minutes moderate-to-vigorous activity) was objectively assessed by accelerometry for a total of 8832 days between 2011 and 2014. At the same time, time in bed (h) and subjective sleep quality (1-6) were diaried each morning. In models corrected for confounding, we found that lunar phase was not significantly associated with physical activity, subjective sleep quality or time in bed in either sex, regardless of season. Observed relationships varied randomly in direction between models, suggesting artefact. Thus, this large, objectively-measured and well-controlled population of adolescents displayed no lunar periodicity in objective physical activity, subjective sleep quality or time in bed.

  1. Body stability and muscle and motor cortex activity during walking with wide stance

    PubMed Central

    Farrell, Brad J.; Bulgakova, Margarita A.; Beloozerova, Irina N.; Sirota, Mikhail G.

    2014-01-01

    Biomechanical and neural mechanisms of balance control during walking are still poorly understood. In this study, we examined the body dynamic stability, activity of limb muscles, and activity of motor cortex neurons [primarily pyramidal tract neurons (PTNs)] in the cat during unconstrained walking and walking with a wide base of support (wide-stance walking). By recording three-dimensional full-body kinematics we found for the first time that during unconstrained walking the cat is dynamically unstable in the forward direction during stride phases when only two diagonal limbs support the body. In contrast to standing, an increased lateral between-paw distance during walking dramatically decreased the cat's body dynamic stability in double-support phases and prompted the cat to spend more time in three-legged support phases. Muscles contributing to abduction-adduction actions had higher activity during stance, while flexor muscles had higher activity during swing of wide-stance walking. The overwhelming majority of neurons in layer V of the motor cortex, 82% and 83% in the forelimb and hindlimb representation areas, respectively, were active differently during wide-stance walking compared with unconstrained condition, most often by having a different depth of stride-related frequency modulation along with a different mean discharge rate and/or preferred activity phase. Upon transition from unconstrained to wide-stance walking, proximal limb-related neuronal groups subtly but statistically significantly shifted their activity toward the swing phase, the stride phase where most of body instability occurs during this task. The data suggest that the motor cortex participates in maintenance of body dynamic stability during locomotion. PMID:24790167

  2. Asymptotic theory of time-varying social networks with heterogeneous activity and tie allocation.

    PubMed

    Ubaldi, Enrico; Perra, Nicola; Karsai, Márton; Vezzani, Alessandro; Burioni, Raffaella; Vespignani, Alessandro

    2016-10-24

    The dynamic of social networks is driven by the interplay between diverse mechanisms that still challenge our theoretical and modelling efforts. Amongst them, two are known to play a central role in shaping the networks evolution, namely the heterogeneous propensity of individuals to i) be socially active and ii) establish a new social relationships with their alters. Here, we empirically characterise these two mechanisms in seven real networks describing temporal human interactions in three different settings: scientific collaborations, Twitter mentions, and mobile phone calls. We find that the individuals' social activity and their strategy in choosing ties where to allocate their social interactions can be quantitatively described and encoded in a simple stochastic network modelling framework. The Master Equation of the model can be solved in the asymptotic limit. The analytical solutions provide an explicit description of both the system dynamic and the dynamical scaling laws characterising crucial aspects about the evolution of the networks. The analytical predictions match with accuracy the empirical observations, thus validating the theoretical approach. Our results provide a rigorous dynamical system framework that can be extended to include other processes shaping social dynamics and to generate data driven predictions for the asymptotic behaviour of social networks.

  3. Asymptotic theory of time-varying social networks with heterogeneous activity and tie allocation

    NASA Astrophysics Data System (ADS)

    Ubaldi, Enrico; Perra, Nicola; Karsai, Márton; Vezzani, Alessandro; Burioni, Raffaella; Vespignani, Alessandro

    2016-10-01

    The dynamic of social networks is driven by the interplay between diverse mechanisms that still challenge our theoretical and modelling efforts. Amongst them, two are known to play a central role in shaping the networks evolution, namely the heterogeneous propensity of individuals to i) be socially active and ii) establish a new social relationships with their alters. Here, we empirically characterise these two mechanisms in seven real networks describing temporal human interactions in three different settings: scientific collaborations, Twitter mentions, and mobile phone calls. We find that the individuals’ social activity and their strategy in choosing ties where to allocate their social interactions can be quantitatively described and encoded in a simple stochastic network modelling framework. The Master Equation of the model can be solved in the asymptotic limit. The analytical solutions provide an explicit description of both the system dynamic and the dynamical scaling laws characterising crucial aspects about the evolution of the networks. The analytical predictions match with accuracy the empirical observations, thus validating the theoretical approach. Our results provide a rigorous dynamical system framework that can be extended to include other processes shaping social dynamics and to generate data driven predictions for the asymptotic behaviour of social networks.

  4. Asymptotic theory of time-varying social networks with heterogeneous activity and tie allocation

    PubMed Central

    Ubaldi, Enrico; Perra, Nicola; Karsai, Márton; Vezzani, Alessandro; Burioni, Raffaella; Vespignani, Alessandro

    2016-01-01

    The dynamic of social networks is driven by the interplay between diverse mechanisms that still challenge our theoretical and modelling efforts. Amongst them, two are known to play a central role in shaping the networks evolution, namely the heterogeneous propensity of individuals to i) be socially active and ii) establish a new social relationships with their alters. Here, we empirically characterise these two mechanisms in seven real networks describing temporal human interactions in three different settings: scientific collaborations, Twitter mentions, and mobile phone calls. We find that the individuals’ social activity and their strategy in choosing ties where to allocate their social interactions can be quantitatively described and encoded in a simple stochastic network modelling framework. The Master Equation of the model can be solved in the asymptotic limit. The analytical solutions provide an explicit description of both the system dynamic and the dynamical scaling laws characterising crucial aspects about the evolution of the networks. The analytical predictions match with accuracy the empirical observations, thus validating the theoretical approach. Our results provide a rigorous dynamical system framework that can be extended to include other processes shaping social dynamics and to generate data driven predictions for the asymptotic behaviour of social networks. PMID:27774998

  5. Cytoplasmic streaming in Drosophila oocytes varies with kinesin activity and correlates with the microtubule cytoskeleton architecture.

    PubMed

    Ganguly, Sujoy; Williams, Lucy S; Palacios, Isabel M; Goldstein, Raymond E

    2012-09-18

    Cells can localize molecules asymmetrically through the combined action of cytoplasmic streaming, which circulates their fluid contents, and specific anchoring mechanisms. Streaming also contributes to the distribution of nutrients and organelles such as chloroplasts in plants, the asymmetric position of the meiotic spindle in mammalian embryos, and the developmental potential of the zygote, yet little is known quantitatively about the relationship between streaming and the motor activity which drives it. Here we use Particle Image Velocimetry to quantify the statistical properties of Kinesin-dependent streaming during mid-oogenesis in Drosophila. We find that streaming can be used to detect subtle changes in Kinesin activity and that the flows reflect the architecture of the microtubule cytoskeleton. Furthermore, based on characterization of the rheology of the cytoplasm in vivo, we establish estimates of the number of Kinesins required to drive the observed streaming. Using this in vivo data as the basis of a model for transport, we suggest that the disordered character of transport at mid-oogenesis, as revealed by streaming, is an important component of the localization dynamics of the body plan determinant oskar mRNA.

  6. The varied functions of aluminium-activated malate transporters–much more than aluminium resistance

    PubMed Central

    Palmer, Antony J.; Baker, Alison; Muench, Stephen P.

    2016-01-01

    The ALMT (aluminium-activated malate transporter) family comprises a functionally diverse but structurally similar group of ion channels. They are found ubiquitously in plant species, expressed throughout different tissues, and located in either the plasma membrane or tonoplast. The first family member identified was TaALMT1, discovered in wheat root tips, which was found to be involved in aluminium resistance by means of malate exudation into the soil. However, since this discovery other family members have been shown to have many other functions such as roles in stomatal opening, general anionic homoeostasis, and in economically valuable traits such as fruit flavour. Recent evidence has also shown that ALMT proteins can act as key molecular actors in GABA (γ-aminobutyric acid) signalling, the first evidence that GABA can act as a signal transducer in plants. PMID:27284052

  7. Fate of malathion and a phosphonic acid in activated sludge with varying solids retention times.

    PubMed

    Janeczko, Allen K; Walters, Edward B; Schuldt, Steven J; Magnuson, Matthew L; Willison, Stuart A; Brown, Lisa M; Ruiz, Oscar N; Felker, Daniel L; Racz, LeeAnn

    2014-06-15

    This study examined the ability of activated sludge (AS) to sorb and biodegrade ethylmethylphosphonic acid (EMPA) and malathion, a degradation product and surrogate, respectively, for an organophosphate chemical warfare agent. Sorption equilibrium isotherm experiments indicate that sorption of EMPA and malathion to AS is negligible. EMPA at a concentration of 1 mg L(-1) degraded by approximately 30% with apparent first-order kinetics, possibly via co-metabolism from nitrification. Heterotrophic bacteria and abiotic mechanisms, however, are largely responsible for malathion degradation also with apparent first-order kinetics. EMPA did not inhibit chemical oxygen demand (COD) oxidation or nitrification activity, although malathion did appear to induce a stress response resulting in inhibition of COD oxidation. The study also included a 30-day experiment in which malathion, at a concentration of 5 mg L(-1), was repeatedly fed to AS in bench-scale sequencing batch reactors (SBRs) operating at different solids retention times (SRTs). Peak malathion concentrations occurred at day 4.5, with the longer SRTs yielding greater peak malathion concentrations. The AS reduced the malathion concentrations to nearly zero by day 10 for all SRTs, even when the malathion concentration in the influent increased to 20.8 mg L(-1). The data suggest a biodegradation pathway for malathion involving an oxygenase. Phylogenetic analyses revealed that all samples had an abundance of Zoogloea, though there was greater bacterial diversity in the SBR with the SRT of 50 days. The SBR with an SRT of 9.5 days had an apparent reduction in the diversity of the bacterial community.

  8. Local and Widely Distributed EEG Activity in Schizophrenia With Prevalence of Negative Symptoms.

    PubMed

    Grin-Yatsenko, Vera A; Ponomarev, Valery A; Pronina, Marina V; Poliakov, Yury I; Plotnikova, Irina V; Kropotov, Juri D

    2017-01-01

    We evaluated EEG frequency abnormalities in resting state (eyes closed and eyes open) EEG in a group of chronic schizophrenia patients as compared with healthy subjects. The study included 3 methods of analysis of deviation of EEG characteristics: genuine EEG, current source density (CSD), and group independent component (gIC). All 3 methods have shown that the EEG in schizophrenia patients is characterized by enhanced low-frequency (delta and theta) and high-frequency (beta) activity in comparison with the control group. However, the spatial pattern of differences was dependent on the type of method used. Comparative analysis has shown that increased EEG power in schizophrenia patients apparently concerns both widely spatially distributed components and local components of signal. Furthermore, the observed differences in the delta and theta range can be described mainly by the local components, and those in the beta range mostly by spatially widely distributed ones. The possible nature of the widely distributed activity is discussed.

  9. Gender Differences in Barriers to Physical Activity among College Students Reporting Varying Levels of Regular Physical Activity

    ERIC Educational Resources Information Center

    Munford, Shawn N.

    2011-01-01

    Researchers have studied the primary determinants of physical activity in an effort to enhance health promotion initiatives nationwide. These physical activity determinants have been observed to differ among various segments of the population, suggesting a further examination of physical activity barriers among differing populations. Little…

  10. Active dynamics of colloidal particles in time-varying laser speckle patterns

    PubMed Central

    Bianchi, Silvio; Pruner, Riccardo; Vizsnyiczai, Gaszton; Maggi, Claudio; Di Leonardo, Roberto

    2016-01-01

    Colloidal particles immersed in a dynamic speckle pattern experience an optical force that fluctuates both in space and time. The resulting dynamics presents many interesting analogies with a broad class of non-equilibrium systems like: active colloids, self propelled microorganisms, transport in dynamical intracellular environments. Here we show that the use of a spatial light modulator allows to generate light fields that fluctuate with controllable space and time correlations and a prescribed average intensity profile. In particular we generate ring-shaped random patterns that can confine a colloidal particle over a quasi one-dimensional random energy landscape. We find a mean square displacement that is diffusive at both short and long times, while a superdiffusive or subdiffusive behavior is observed at intermediate times depending on the value of the speckles correlation time. We propose two alternative models for the mean square displacement in the two limiting cases of a short or long speckles correlation time. A simple interpolation formula is shown to account for the full phenomenology observed in the mean square displacement across the entire range from fast to slow fluctuating speckles. PMID:27279540

  11. Multistability of neural networks with discontinuous non-monotonic piecewise linear activation functions and time-varying delays.

    PubMed

    Nie, Xiaobing; Zheng, Wei Xing

    2015-05-01

    This paper is concerned with the problem of coexistence and dynamical behaviors of multiple equilibrium points for neural networks with discontinuous non-monotonic piecewise linear activation functions and time-varying delays. The fixed point theorem and other analytical tools are used to develop certain sufficient conditions that ensure that the n-dimensional discontinuous neural networks with time-varying delays can have at least 5(n) equilibrium points, 3(n) of which are locally stable and the others are unstable. The importance of the derived results is that it reveals that the discontinuous neural networks can have greater storage capacity than the continuous ones. Moreover, different from the existing results on multistability of neural networks with discontinuous activation functions, the 3(n) locally stable equilibrium points obtained in this paper are located in not only saturated regions, but also unsaturated regions, due to the non-monotonic structure of discontinuous activation functions. A numerical simulation study is conducted to illustrate and support the derived theoretical results.

  12. The Regulation of Skeletal Muscle Active Hyperemia: The Differential Role of Adenosine in Muscles of Varied Fiber Types

    DTIC Science & Technology

    1986-04-21

    0.2 Hz and three mnscles ~;timulated to contract at 0.4 Hz during BADA infuston. These m~tabolites were also mea~•1red in two muscles contractin ~ at...APR 1986 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE The Regulation of Skeletal Muscle Active Hyperemia: The Differential...Role of Adenosine in Muscles of Varied Fiber Types 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  13. Quantitative intramuscular myoelectric activity of quadratus lumborum during a wide variety of tasks.

    PubMed

    McGill, S; Juker, D; Kropf, P

    1996-04-01

    Intramuscular fine-wire electrodes monitored the electromyographic activity of quadratus lumborum in four young adults. A wide variety of tasks were performed including flexion tasks, lateral bending, twisting, extension, and lifting tasks. Heavy lifts of barbell weights up to 70 kg activated the quadratus lumborum 74% of their maximum on average while surface recording of erector spinae (L(3)) were only 62% of their maximum activation. The quadratus lumborum was more active (54%) than other muscles during isometric side support postures where the body is held horizontally almost parallel to the floor as the subjects supported themselves on one elbow on the floor together with both feet. Furthermore, it increased activation in response to increasing compression in static upright standing postures. RELEVANCE:--Electromyographic evidence, together with architectural features make the quadratus lumborum a better stabilizer of the spine than psoas. Use of horizontal 'side support' exercise to train this muscle would appear to be a wise choice.

  14. Does the Effect of a Physical Activity Behavioral Intervention Vary by Characteristics of People with Multiple Sclerosis?

    PubMed Central

    Dlugonski, Deirdre; Pilutti, Lara A.; Klaren, Rachel E.

    2015-01-01

    Background: Behavioral interventions have significantly increased physical activity in people with multiple sclerosis (MS). Nevertheless, there has been interindividual variability in the pattern and magnitude of change. This study documented the efficacy and variability of a behavioral intervention for changing physical activity and examined the possibility that efficacy varied by the characteristics of individuals with MS. Methods: Eighty-two people with MS were randomly assigned to one of two conditions: behavioral intervention (n = 41) or waitlist control (n = 41). We collected information before the study on MS type, disability status, weight status based on body-mass index, and current medications. Furthermore, all participants completed the Godin Leisure Time Exercise Questionnaire and the abbreviated International Physical Activity Questionnaire and wore an accelerometer for 1 week to measure minutes of moderate-to-vigorous physical activity before and after the 6-month intervention period. Results: Analysis of covariance (ANCOVA) indicated that participants in the behavioral intervention had significantly higher levels of physical activity than control participants after the 6-month period (P < .001). There was substantial interindividual variability in the magnitude of change, and ANCOVA indicated that MS type (relapsing vs. progressive) (P < .01), disability status (mild vs. moderate) (P < .01), and weight status (normal weight vs. overweight/obese) (P < .05) moderated the efficacy of the behavioral intervention. Conclusions: The behavioral intervention was associated with improvements in physical activity, particularly for those with mild disability, relapsing-remitting MS, or normal weight status. PMID:25892976

  15. Wide-field optical mapping of neural activity and brain haemodynamics: considerations and novel approaches

    PubMed Central

    Ma, Ying; Shaik, Mohammed A.; Kozberg, Mariel G.; Thibodeaux, David N.; Zhao, Hanzhi T.; Yu, Hang

    2016-01-01

    Although modern techniques such as two-photon microscopy can now provide cellular-level three-dimensional imaging of the intact living brain, the speed and fields of view of these techniques remain limited. Conversely, two-dimensional wide-field optical mapping (WFOM), a simpler technique that uses a camera to observe large areas of the exposed cortex under visible light, can detect changes in both neural activity and haemodynamics at very high speeds. Although WFOM may not provide single-neuron or capillary-level resolution, it is an attractive and accessible approach to imaging large areas of the brain in awake, behaving mammals at speeds fast enough to observe widespread neural firing events, as well as their dynamic coupling to haemodynamics. Although such wide-field optical imaging techniques have a long history, the advent of genetically encoded fluorophores that can report neural activity with high sensitivity, as well as modern technologies such as light emitting diodes and sensitive and high-speed digital cameras have driven renewed interest in WFOM. To facilitate the wider adoption and standardization of WFOM approaches for neuroscience and neurovascular coupling research, we provide here an overview of the basic principles of WFOM, considerations for implementation of wide-field fluorescence imaging of neural activity, spectroscopic analysis and interpretation of results. This article is part of the themed issue ‘Interpreting BOLD: a dialogue between cognitive and cellular neuroscience’. PMID:27574312

  16. Genome-wide investigation of schizophrenia associated plasma Ndel1 enzyme activity.

    PubMed

    Gadelha, Ary; Coleman, Jonathan; Breen, Gerome; Mazzoti, Diego Robles; Yonamine, Camila M; Pellegrino, Renata; Ota, Vanessa Kiyomi; Belangero, Sintia Iole; Glessner, Joseph; Sleiman, Patrick; Hakonarson, Hakon; Hayashi, Mirian A F; Bressan, Rodrigo A

    2016-04-01

    Ndel1 is a DISC1-interacting oligopeptidase that cleaves in vitro neuropeptides as neurotensin and bradykinin, and which has been associated with both neuronal migration and neurite outgrowth. We previously reported that plasma Ndel1 enzyme activity is lower in patients with schizophrenia (SCZ) compared to healthy controls (HCs). To our knowledge, no previous study has investigated the genetic factors associated with the plasma Ndel1 enzyme activity. In the current analyses, samples from 83 SCZ patients and 92 control subjects that were assayed for plasma Ndel1 enzyme activity were genotyped on Illumina Omni Express arrays. A genetic relationship matrix using genome-wide information was then used for ancestry correction, and association statistics were calculated genome-wide. Ndel1 enzyme activity was significantly lower in patients with SCZ (t=4.9; p<0.001) and was found to be associated with CAMK1D, MAGI2, CCDC25, and GABGR3, at a level of suggestive significance (p<10(-6)), independent of the clinical status. Then, we performed a model to investigate the observed differences for case/control measures. 2 SNPs at region 1p22.2 reached the p<10(-7) level. ZFPM2 and MAD1L1 were the only two genes with more than one hit at 10(-6) order of p value. Therefore, Ndel1 enzyme activity is a complex trait influenced by many different genetic variants that may contribute to SCZ physiopathology.

  17. A wide range of activity duration cutoffs provided unbiased estimates of exposure to computer use.

    PubMed

    Chang, Che-Hsu; Johnson, Peter W; Dennerlein, Jack T

    2008-12-01

    Integrative computer usage monitors have become widely used in epidemiologic studies to investigate the exposure-response relationship of computer-related musculoskeletal disorders. These software programs typically estimate the exposure duration of computer use by summing precisely recorded durations of input device activities and durations of inactivity periods shorter than a predetermined activity duration cutoff value, usually 30 or 60 sec. The goal of this study was to systematically compare the validity of a wide range of cutoff values. Computer use activity of 20 office workers was observed for 4 consecutive hours using both a video camera and a usage monitor. Video recordings from the camera were analyzed using specific observational criteria to determine computer use duration. This observed duration then served as the reference and was compared with 238 estimates of computer use duration calculated from the usage monitor data using activity duration cutoffs ranging from 3 to 240 sec in 1-sec increments. Estimates calculated with cutoffs ranging from 28 to 60 sec were highly correlated with the observed duration (Spearman's correlation 0.87 to 0.92) and had nearly ideal linear relationships with the observed duration (slopes and r-squares close to one, and intercepts close to zero). For the same range of cutoff values, when the observed and estimated durations were compared for dichotomous exposure classification across participants, minimal exposure misclassification was observed. It is concluded that activity duration cutoffs ranging from 28 to 60 sec provided unbiased estimates of computer use duration.

  18. UWALK: the development of a multi-strategy, community-wide physical activity program.

    PubMed

    Jennings, Cally A; Berry, Tanya R; Carson, Valerie; Culos-Reed, S Nicole; Duncan, Mitch J; Loitz, Christina C; McCormack, Gavin R; McHugh, Tara-Leigh F; Spence, John C; Vallance, Jeff K; Mummery, W Kerry

    2016-06-09

    UWALK is a multi-strategy, multi-sector, theory-informed, community-wide approach using e and mHealth to promote physical activity in Alberta, Canada. The aim of UWALK is to promote physical activity, primarily via the accumulation of steps and flights of stairs, through a single over-arching brand. This paper describes the development of the UWALK program. A social ecological model and the social cognitive theory guided the development of key strategies, including the marketing and communication activities, establishing partnerships with key stakeholders, and e and mHealth programs. The program promotes the use of physical activity monitoring devices to self-monitor physical activity. This includes pedometers, electronic devices, and smartphone applications. In addition to entering physical activity data manually, the e and mHealth program provides the function for objective data to be automatically uploaded from select electronic devices (Fitbit®, Garmin and the smartphone application Moves) The RE-AIM framework is used to guide the evaluation of UWALK. Funding for the program commenced in February 2013. The UWALK brand was introduced on April 12, 2013 with the official launch, including the UWALK website on September 20, 2013. This paper describes the development and evaluation framework of a physical activity promotion program. This program has the potential for population level dissemination and uptake of an ecologically valid physical activity promotion program that is evidence-based and theoretically framed.

  19. Proteome-wide analysis of nonsynonymous single-nucleotide variations in active sites of human proteins.

    PubMed

    Dingerdissen, Hayley; Motwani, Mona; Karagiannis, Konstantinos; Simonyan, Vahan; Mazumder, Raja

    2013-03-01

    An enzyme's active site is essential to normal protein activity such that any disruptions at this site may lead to dysfunction and disease. Nonsynonymous single-nucleotide variations (nsSNVs), which alter the amino acid sequence, are one type of disruption that can alter the active site. When this occurs, it is assumed that enzyme activity will vary because of the criticality of the site to normal protein function. We integrate nsSNV data and active site annotations from curated resources to identify all active-site-impacting nsSNVs in the human genome and search for all pathways observed to be associated with this data set to assess the likely consequences. We find that there are 934 unique nsSNVs that occur at the active sites of 559 proteins. Analysis of the nsSNV data shows an over-representation of arginine and an under-representation of cysteine, phenylalanine and tyrosine when comparing the list of nsSNV-impacted active site residues with the list of all possible proteomic active site residues, implying a potential bias for or against variation of these residues at the active site. Clustering analysis shows an abundance of hydrolases and transferases. Pathway and functional analysis shows several pathways over- or under-represented in the data set, with the most significantly affected pathways involved in carbohydrate metabolism. We provide a table of 32 variation-substrate/product pairs that can be used in targeted metabolomics experiments to assay the effects of specific variations. In addition, we report the significant prevalence of aspartic acid to histidine variation in eight proteins associated with nine diseases including glycogen storage diseases, lacrimo-auriculo-dento-digital syndrome, Parkinson's disease and several cancers.

  20. Individual differences in oscillatory brain activity in response to varying attentional demands during a word recall and oculomotor dual task

    PubMed Central

    Kwon, Gusang; Lim, Sanghyun; Kim, Min-Young; Kwon, Hyukchan; Lee, Yong-Ho; Kim, Kiwoong; Lee, Eun-Ju; Suh, Minah

    2015-01-01

    Every day, we face situations that involve multi-tasking. How our brain utilizes cortical resources during multi-tasking is one of many interesting research topics. In this study, we tested whether a dual-task can be differentiated in the neural and behavioral responses of healthy subjects with varying degree of working memory capacity (WMC). We combined word recall and oculomotor tasks because they incorporate common neural networks including the fronto-parietal (FP) network. Three different types of oculomotor tasks (eye fixation, Fix-EM; predictive and random smooth pursuit eye movement, P-SPEM and R-SPEM) were combined with two memory load levels (low-load: five words, high-load: 10 words) for a word recall task. Each of those dual-task combinations was supposed to create varying cognitive loads on the FP network. We hypothesize that each dual-task requires different cognitive strategies for allocating the brain’s limited cortical resources and affects brain oscillation of the FP network. In addition, we hypothesized that groups with different WMC will show differential neural and behavioral responses. We measured oscillatory brain activity with simultaneous MEG and EEG recordings and behavioral performance by word recall. Prominent frontal midline (FM) theta (4–6 Hz) synchronization emerged in the EEG of the high-WMC group experiencing R-SPEM with high-load conditions during the early phase of the word maintenance period. Conversely, significant parietal upper alpha (10–12 Hz) desynchronization was observed in the EEG and MEG of the low-WMC group experiencing P-SPEM under high-load conditions during the same period. Different brain oscillatory patterns seem to depend on each individual’s WMC and varying attentional demands from different dual-task combinations. These findings suggest that specific brain oscillations may reflect different strategies for allocating cortical resources during combined word recall and oculomotor dual-tasks. PMID:26175681

  1. Kinome-wide activity modeling from diverse public high-quality data sets.

    PubMed

    Schürer, Stephan C; Muskal, Steven M

    2013-01-28

    Large corpora of kinase small molecule inhibitor data are accessible to public sector research from thousands of journal article and patent publications. These data have been generated employing a wide variety of assay methodologies and experimental procedures by numerous laboratories. Here we ask the question how applicable these heterogeneous data sets are to predict kinase activities and which characteristics of the data sets contribute to their utility. We accessed almost 500,000 molecules from the Kinase Knowledge Base (KKB) and after rigorous aggregation and standardization generated over 180 distinct data sets covering all major groups of the human kinome. To assess the value of the data sets, we generated hundreds of classification and regression models. Their rigorous cross-validation and characterization demonstrated highly predictive classification and quantitative models for the majority of kinase targets if a minimum required number of active compounds or structure-activity data points were available. We then applied the best classifiers to compounds most recently profiled in the NIH Library of Integrated Network-based Cellular Signatures (LINCS) program and found good agreement of profiling results with predicted activities. Our results indicate that, although heterogeneous in nature, the publically accessible data sets are exceedingly valuable and well suited to develop highly accurate predictors for practical Kinome-wide virtual screening applications and to complement experimental kinase profiling.

  2. Novel structurally varied N-alkyl 1,4-dihydropyridines as ABCB1 inhibitors: structure-activity relationships, biological activity and first bioanalytical evaluation.

    PubMed

    Hilgeroth, Andreas; Baumert, Christiane; Coburger, Claudius; Seifert, Marianne; Krawczyk, Sören; Hempel, Cornelius; Neubauer, Felix; Krug, Martin; Molnár, Josef; Lage, Hermann

    2013-06-01

    Series of structurally varied N-alkyl 1,4-dihydropyridines and novel benzo-annelated derivatives as 1,4- dihydroquinolines have been characterized as ABCB1 inhibitors. Structure-activity relationships (SARs) are discussed. Cytotoxic activities of selected compounds have been determined. A first bioanalysis of ABCB1 substrate properties has been carried out in a cell-based model. Compounds with highest ABCB1 inhibiting activities were no substrates of ABCB1 and not transported by the efflux pump, thus profiling the new ABCB1 inhibitors.

  3. The Chromospheric Activity-Age Relation for M Dwarf Stars in Wide Binary Systems

    NASA Astrophysics Data System (ADS)

    Silvestri, N. M.

    2002-12-01

    We present new chromospheric activity-age relations for M dwarf stars in wide binary systems with white dwarf companions. This study is unique in that we use the cooling age of the white dwarf to determine the age of the M dwarf star in the binary system. Assuming that the members of the gravitationally bound system are coeval, the age of the white dwarf is therefore the age of the M dwarf companion. The colors and magnitudes at which chromospheric activity becomes pervasive (at the ``Hα limit") in M stars have been shown to correlate linearly with log(age) in young (<= 4 Gyr) cluster M dwarfs. We find that M dwarfs in wide binaries older than 4 Gyr depart from this linear relation and are found to have activity at colors and magnitudes both bluer and brighter than predicted by M dwarf cluster relations. Also, activity is present in nearly all cluster M dwarfs above the ``Hα limit", whereas not all binary M dwarfs are found to be active above this limit. These relations differ considerably from the rotationally driven dynamo relation for F, G, and K stars that suggests a different magnetic heating mechanism for M dwarf stars. The new relations extend to ages beyond the oldest ages provided by cluster M dwarf activity-age estimates. However, more work is necessary to decrease the uncertainties in these new relations and extend them to later (>= M5.5) spectral types. This work was supported by the NASA Graduate Researchers Program Grant NGT 200415; A Grant-in-Aid of Research from the National Academy of Sciences administered by Sigma Xi, The Scientific Research Society; NASA Grant Y701296; and NSF Grant AST 0206115.

  4. A Highly Linear and Wide Input Range Four-Quadrant CMOS Analog Multiplier Using Active Feedback

    NASA Astrophysics Data System (ADS)

    Huang, Zhangcai; Jiang, Minglu; Inoue, Yasuaki

    Analog multipliers are one of the most important building blocks in analog signal processing circuits. The performance with high linearity and wide input range is usually required for analog four-quadrant multipliers in most applications. Therefore, a highly linear and wide input range four-quadrant CMOS analog multiplier using active feedback is proposed in this paper. Firstly, a novel configuration of four-quadrant multiplier cell is presented. Its input dynamic range and linearity are improved significantly by adding two resistors compared with the conventional structure. Then based on the proposed multiplier cell configuration, a four-quadrant CMOS analog multiplier with active feedback technique is implemented by two operational amplifiers. Because of both the proposed multiplier cell and active feedback technique, the proposed multiplier achieves a much wider input range with higher linearity than conventional structures. The proposed multiplier was fabricated by a 0.6µm CMOS process. Experimental results show that the input range of the proposed multiplier can be up to 5.6Vpp with 0.159% linearity error on VX and 4.8Vpp with 0.51% linearity error on VY for ±2.5V power supply voltages, respectively.

  5. Endophytic fungus strain 28 isolated from Houttuynia cordata possesses wide-spectrum antifungal activity.

    PubMed

    Pan, Feng; Liu, Zheng-Qiong; Chen, Que; Xu, Ying-Wen; Hou, Kai; Wu, Wei

    2016-01-01

    The aim of this paper is to identify and investigate an endophytic fungus (strain 28) that was isolated from Houttuynia cordata Thunb, a famous and widely-used Traditional Chinese Medicine. Based on morphological methods and a phylogenetic analysis of ITS sequences, this strain was identified as Chaetomium globosum. An antifungal activity bioassay demonstrated that the crude ethyl acetate (EtOAc) extracts of strain 28 had a wide antifungal spectrum and strong antimicrobial activity, particularly against Exserohilum turcicum (Pass.) Leonard et Suggs, Botrytis cinerea persoon and Botrytis cinerea Pers. ex Fr. Furthermore, the fermentation conditions, extraction method and the heat stability of antifungal substances from strain 28 were also studied. The results showed that optimal antifungal activity can be obtained with the following parameters: using potato dextrose broth (PDB) as the base culture medium, fermentation for 4-8d (initial pH: 7.5), followed by extraction with EtOAc. The extract was stable at temperatures up to 80°C. This is the first report on the isolation of endophytic C. globosum from H. cordata to identify potential alternative biocontrol agents that could provide new opportunities for practical applications involving H. cordata.

  6. High-throughput mapping of brain-wide activity in awake and drug-responsive vertebrates.

    PubMed

    Lin, Xudong; Wang, Shiqi; Yu, Xudong; Liu, Zhuguo; Wang, Fei; Li, Wai Tsun; Cheng, Shuk Han; Dai, Qiuyun; Shi, Peng

    2015-02-07

    The reconstruction of neural activity across complete neural circuits, or brain activity mapping, has great potential in both fundamental and translational neuroscience research. Larval zebrafish, a vertebrate model, has recently been demonstrated to be amenable to whole brain activity mapping in behaving animals. Here we demonstrate a microfluidic array system ("Fish-Trap") that enables high-throughput mapping of brain-wide activity in awake larval zebrafish. Unlike the commonly practiced larva-processing methods using a rigid gel or a capillary tube, which are laborious and time-consuming, the hydrodynamic design of our microfluidic chip allows automatic, gel-free, and anesthetic-free processing of tens of larvae for microscopic imaging with single-cell resolution. Notably, this system provides the capability to directly couple pharmaceutical stimuli with real-time recording of neural activity in a large number of animals, and the local and global effects of pharmacoactive drugs on the nervous system can be directly visualized and evaluated by analyzing drug-induced functional perturbation within or across different brain regions. Using this technology, we tested a set of neurotoxin peptides and obtained new insights into how to exploit neurotoxin derivatives as therapeutic agents. The novel and versatile "Fish-Trap" technology can be readily unitized to study other stimulus (optical, acoustic, or physical) associated functional brain circuits using similar experimental strategies.

  7. A novel design of semi-active hydraulic mount with wide-band tunable notch frequency

    NASA Astrophysics Data System (ADS)

    Wang, Min; Yao, Guo-feng; Zhao, Jing-zhou; Qin, Min

    2014-04-01

    Hydraulic engine mount is advanced vibration isolator with superior performance to reduce vibration transferred from engine to chassis. As the stiffness at notch frequency is small, some semi-active or active hydraulic mounts tune some parameters to let notch frequency coincide with exciting frequency for better vibration isolation performance. It is discovered the current semi-active mounts can tune the notch frequency in narrow frequency band when only one parameter is tuned. A novel semi-active hydraulic engine mount design which introduces screw thread is proposed and researched in the paper. This hydraulic mount can control both cross section area and the length of inertia track and the theoretical tunable notch frequency band is [0, ∞). Theoretical work is carried out to uncover the capability for the proposed design to tune notch frequency. Simulation work is performed to understand its high vibration isolation performance. For the purpose of energy conservation, the friction self-locking is introduced. This denotes once the mount is tuned at optimal condition, the energy can be cut off and the optimal condition will never change. We also determine the best time to tune the parameters of the proposed mount in order to decrease the acting force. The proposed semi-active mount has capability to obtain wide band tunable notch frequency and has merit of energy conservation.

  8. Active chromatin domains are defined by acetylation islands revealed by genome-wide mapping.

    PubMed

    Roh, Tae-Young; Cuddapah, Suresh; Zhao, Keji

    2005-03-01

    The identity and developmental potential of a human cell is specified by its epigenome that is largely defined by patterns of chromatin modifications including histone acetylation. Here we report high-resolution genome-wide mapping of diacetylation of histone H3 at Lys 9 and Lys 14 in resting and activated human T cells by genome-wide mapping technique (GMAT). Our data show that high levels of the H3 acetylation are detected in gene-rich regions. The chromatin accessibility and gene expression of a genetic domain is correlated with hyperacetylation of promoters and other regulatory elements but not with generally elevated acetylation of the entire domain. Islands of acetylation are identified in the intergenic and transcribed regions. The locations of the 46,813 acetylation islands identified in this study are significantly correlated with conserved noncoding sequences (CNSs) and many of them are colocalized with known regulatory elements in T cells. TCR signaling induces 4045 new acetylation loci that may mediate the global chromatin remodeling and gene activation. We propose that the acetylation islands are epigenetic marks that allow prediction of functional regulatory elements.

  9. Active chromatin domains are defined by acetylation islands revealed by genome-wide mapping

    PubMed Central

    Roh, Tae-Young; Cuddapah, Suresh; Zhao, Keji

    2005-01-01

    The identity and developmental potential of a human cell is specified by its epigenome that is largely defined by patterns of chromatin modifications including histone acetylation. Here we report high-resolution genome-wide mapping of diacetylation of histone H3 at Lys 9 and Lys 14 in resting and activated human T cells by genome-wide mapping technique (GMAT). Our data show that high levels of the H3 acetylation are detected in gene-rich regions. The chromatin accessibility and gene expression of a genetic domain is correlated with hyperacetylation of promoters and other regulatory elements but not with generally elevated acetylation of the entire domain. Islands of acetylation are identified in the intergenic and transcribed regions. The locations of the 46,813 acetylation islands identified in this study are significantly correlated with conserved noncoding sequences (CNSs) and many of them are colocalized with known regulatory elements in T cells. TCR signaling induces 4045 new acetylation loci that may mediate the global chromatin remodeling and gene activation. We propose that the acetylation islands are epigenetic marks that allow prediction of functional regulatory elements. PMID:15706033

  10. Breaking the Meyer-Overton rule: predicted effects of varying stiffness and interfacial activity on the intrinsic potency of anesthetics.

    PubMed Central

    Cantor, R S

    2001-01-01

    Exceptions to the Meyer-Overton rule are commonly cited as evidence against indirect, membrane-mediated mechanisms of general anesthesia. However, another interpretation is possible within the context of an indirect mechanism in which solubilization of an anesthetic in the membrane causes a redistribution of lateral pressures in the membrane, which in turn shifts the conformational equilibrium of membrane proteins such as ligand-gated ion channels. It is suggested that compounds of different stiffness and interfacial activity have different intrinsic potencies, i.e., they cause widely different redistributions of the pressure profile (and thus different effects on protein conformational equilibria) per unit concentration of the compound in the membrane. Calculations incorporating the greater stiffness of perfluoromethylenic chains and the large interfacial attraction of hydroxyl groups predict the higher intrinsic potency of short alkanols than alkanes, the cutoffs in potency of alkanes and alkanols and the much shorter cutoffs for their perfluorinated analogues. Both effects, increased stiffness and interfacial activity, are present in unsaturated hydrocarbon solutes, and the intrinsic potencies are predicted to depend on the magnitude of both effects and on the number and locations of multiple bonds within the molecule. Most importantly, the intrinsic potencies of polymeric alkanols with regularly spaced hydroxyl groups are predicted to rise with increasing chain length, without cutoff; such molecules should serve to distinguish unambiguously between indirect mechanisms and direct binding mechanisms of anesthesia. PMID:11325730

  11. A framework for activity detection in wide-area motion imagery

    SciTech Connect

    Porter, Reid B; Ruggiero, Christy E; Morrison, Jack D

    2009-01-01

    Wide-area persistent imaging systems are becoming increasingly cost effective and now large areas of the earth can be imaged at relatively high frame rates (1-2 fps). The efficient exploitation of the large geo-spatial-temporal datasets produced by these systems poses significant technical challenges for image and video analysis and data mining. In recent years there has been significant progress made on stabilization, moving object detection and tracking and automated systems now generate hundreds to thousands of vehicle tracks from raw data, with little human intervention. However, the tracking performance at this scale, is unreliable and average track length is much smaller than the average vehicle route. This is a limiting factor for applications which depend heavily on track identity, i.e. tracking vehicles from their points of origin to their final destination. In this paper we propose and investigate a framework for wide-area motion imagery (W AMI) exploitation that minimizes the dependence on track identity. In its current form this framework takes noisy, incomplete moving object detection tracks as input, and produces a small set of activities (e.g. multi-vehicle meetings) as output. The framework can be used to focus and direct human users and additional computation, and suggests a path towards high-level content extraction by learning from the human-in-the-loop.

  12. Using Wide-Field Meteor Cameras to Actively Engage Students in Science

    NASA Astrophysics Data System (ADS)

    Kuehn, D. M.; Scales, J. N.

    2012-08-01

    Astronomy has always afforded teachers an excellent topic to develop students' interest in science. New technology allows the opportunity to inexpensively outfit local school districts with sensitive, wide-field video cameras that can detect and track brighter meteors and other objects. While the data-collection and analysis process can be mostly automated by software, there is substantial human involvement that is necessary in the rejection of spurious detections, in performing dynamics and orbital calculations, and the rare recovery and analysis of fallen meteorites. The continuous monitoring allowed by dedicated wide-field surveillance cameras can provide students with a better understanding of the behavior of the night sky including meteors and meteor showers, stellar motion, the motion of the Sun, Moon, and planets, phases of the Moon, meteorological phenomena, etc. Additionally, some students intrigued by the possibility of UFOs and "alien visitors" may find that actual monitoring data can help them develop methods for identifying "unknown" objects. We currently have two ultra-low light-level surveillance cameras coupled to fish-eye lenses that are actively obtaining data. We have developed curricula suitable for middle or high school students in astronomy and earth science courses and are in the process of testing and revising our materials.

  13. Heritability and molecular genetic basis of electrodermal activity: A genome-wide ssociation study

    PubMed Central

    Vaidyanathan, Uma; Isen, Joshua D.; Malone, Stephen M.; Miller, Michael B.; McGue, Matthew; Iacono, William G.

    2014-01-01

    The molecular genetic basis of electrodermal activity (EDA) was analyzed using 527,829 single nucleotide polymorphisms (SNPs) in a large population-representative sample of twins and parents (N = 4,424) in relation to various EDA indices. Biometric analyses suggested that approximately 50% or more of variance in all EDA indices was heritable. The combined effect of all SNPs together accounted for a significant amount of variance in each index, affirming their polygenic basis and heritability. However, none of the SNPs were genome-wide significant for any EDA index. Previously reported SNP associations with disorders such as substance dependence or schizophrenia, which have been linked to EDA abnormalities, were not significant; nor were associations between EDA and genes in specific neurotransmitter systems. These results suggest that EDA is influenced by multiple genes rather than by polymorphisms with large effects. PMID:25387706

  14. Activation of Lumbar Spinal Wide-Dynamic Range Neurons by a Sanshool Derivative

    PubMed Central

    Sawyer, Carolyn M.; Carstens, Mirela Iodi; Simons, Christopher T.; Slack, Jay; McCluskey, T. Scott; Furrer, Stefan; Carstens, E.

    2009-01-01

    The enigmatic sensation of tingle involves the activation of primary sensory neurons by hydroxy-α-sanshool, a tingly agent in Szechuan peppers, by inhibiting two-pore potassium channels. Central mechanisms mediating tingle sensation are unknown. We investigated whether a stable derivative of sanshool—isobutylalkenyl amide (IBA)—excites wide-dynamic range (WDR) spinal neurons that participate in transmission of chemesthetic information from the skin. In anesthetized rats, the majority of WDR and low-threshold units responded to intradermal injection of IBA in a dose-related manner over a >5-min time course and exhibited tachyphylaxis at higher concentrations (1 and 10%). Almost all WDR and low-threshold units additionally responded to the pungent agents mustard oil (allyl isothiocyanate) and/or capsaicin, prompting reclassification of the low-threshold cells as WDR. The results are discussed in terms of the functional role of WDR neurons in mediating tingle sensation. PMID:19164099

  15. The wide-field imager for IXO: status and future activities

    NASA Astrophysics Data System (ADS)

    Strüder, Lothar; Aschauer, Florian; Bautz, Mark; Bombelli, Luca; Burrows, David; Fiorini, Carlo; Fraser, George; Herrmann, Sven; Kendziorra, Eckhard; Kuster, Markus; Lauf, Thomas; Lechner, Peter; Lutz, Gerhard; Majewski, Petra; Meuris, Aline; Porro, Matteo; Reiffers, Jonas; Richter, Rainer; Santangelo, Andrea; Soltau, Heike; Stefanescu, Alexander; Tenzer, Chris; Treis, Johannes; Tsunemi, Hiroshi; de Vita, Giulio; Wilms, Jörn

    2010-07-01

    The Wide Field Imager (WFI) of the International X-ray Observatory (IXO) is an X-ray imaging spectrometer based on a large monolithic DePFET (Depleted P-channel Field Effect Transistor) Active Pixel Sensor. Filling an area of 10 x 10 cm2 with a format of 1024 x 1024 pixels it will cover a field of view of 18 arcmin. The pixel size of 100 x 100 μm2 corresponds to a fivefold oversampling of the telescope's expected 5 arcsec point spread function. The WFI's basic DePFET structure combines the functionalities of sensor and integrated amplifier with nearly Fano-limited energy resolution and high efficiency from 100 eV to 15 keV. The development of dedicated control and amplifier ASICs allows for high frame rates up to 1 kHz and flexible readout modes. Results obtained with representative prototypes with a format of 256 x 256 pixels are presented.

  16. Activation of lumbar spinal wide-dynamic range neurons by a sanshool derivative.

    PubMed

    Sawyer, Carolyn M; Carstens, Mirela Iodi; Simons, Christopher T; Slack, Jay; McCluskey, T Scott; Furrer, Stefan; Carstens, E

    2009-04-01

    The enigmatic sensation of tingle involves the activation of primary sensory neurons by hydroxy-alpha-sanshool, a tingly agent in Szechuan peppers, by inhibiting two-pore potassium channels. Central mechanisms mediating tingle sensation are unknown. We investigated whether a stable derivative of sanshool-isobutylalkenyl amide (IBA)-excites wide-dynamic range (WDR) spinal neurons that participate in transmission of chemesthetic information from the skin. In anesthetized rats, the majority of WDR and low-threshold units responded to intradermal injection of IBA in a dose-related manner over a >5-min time course and exhibited tachyphylaxis at higher concentrations (1 and 10%). Almost all WDR and low-threshold units additionally responded to the pungent agents mustard oil (allyl isothiocyanate) and/or capsaicin, prompting reclassification of the low-threshold cells as WDR. The results are discussed in terms of the functional role of WDR neurons in mediating tingle sensation.

  17. Modeling and classifying human activities from trajectories using a class of space-varying parametric motion fields.

    PubMed

    Nascimento, Jacinto C; Marques, Jorge S; Lemos, João M

    2013-05-01

    Many approaches to trajectory analysis, such as clustering or classification, use probabilistic generative models, thus not requiring trajectory alignment/registration. Switched linear dynamical models (e.g., HMMs) have been used in this context, due to their ability to describe different motion regimes. However, these models are not suitable for handling space-dependent dynamics that are more naturally captured by nonlinear models. As is well known, these are more difficult to identify. In this paper, we propose a new way of modeling trajectories, based on a mixture of parametric motion vector fields that depend on a small number of parameters. Switching among these fields follows a probabilistic mechanism, characterized by a field of stochastic matrices. This approach allows representing a wide variety of trajectories and modeling space-dependent behaviors without using global nonlinear dynamical models. Experimental evaluation is conducted in both synthetic and real scenarios. The latter concerning with human trajectory modeling for activity classification, a central task in video surveillance.

  18. Biotite dissolution in brine at varied temperatures and CO2 pressures: its activation energy and potential CO2 intercalation.

    PubMed

    Hu, Yandi; Jun, Young-Shin

    2012-10-16

    For sustainable geologic CO(2) sequestration (GCS), it is important to understand the effects of temperature and CO(2) pressure on mica's dissolution and surface morphological changes under saline hydrothermal conditions. Batch experiments were conducted with biotite (Fe-end member mica) under conditions relevant to GCS sites (35-95 °C and 75-120 atm CO(2)), and 1 M NaCl solution was used to mimic the brine. With increasing temperature, a transition from incongruent to congruent dissolution of biotite was observed. The dissolution activation energy based on Si release was calculated to be 52 ± 5 kJ mol(-1). By comparison with N(2) experiments, we showed that CO(2) injection greatly enhanced biotite's dissolution and its surface morphology evolutions, such as crack formation and detachment of newly formed fibrous illite. For biotite's dissolution and morphological evolutions, the pH effects of CO(2) were differentiated from the effects of bicarbonate complexation and CO(2) intercalation. Bicarbonate complexation effects on ion release from biotite were found to be minor under our experimental conditions. On the other hand, the CO(2) molecules in brine could get into the biotite interlayer and cause enhanced swelling of the biotite interlayer and hence the observed promotion of biotite surface cracking. The cracking created more reactive surface area in contact with brine and thus enhanced the later ion release from biotite. These results provide new information for understanding CO(2)-brine-mica interactions in saline aquifers with varied temperatures and CO(2) pressures, which can be useful for GCS site selection and operations.

  19. Genome-wide analysis links emerin to neuromuscular junction activity in Caenorhabditis elegans

    PubMed Central

    2014-01-01

    Background Laminopathies are diseases characterized by defects in nuclear envelope structure. A well-known example is Emery-Dreifuss muscular dystrophy, which is caused by mutations in the human lamin A/C and emerin genes. While most nuclear envelope proteins are ubiquitously expressed, laminopathies often affect only a subset of tissues. The molecular mechanisms underlying these tissue-specific manifestations remain elusive. We hypothesize that different functional subclasses of genes might be differentially affected by defects in specific nuclear envelope components. Results Here we determine genome-wide DNA association profiles of two nuclear envelope components, lamin/LMN-1 and emerin/EMR-1 in adult Caenorhabditis elegans. Although both proteins bind to transcriptionally inactive regions of the genome, EMR-1 is enriched at genes involved in muscle and neuronal function. Deletion of either EMR-1 or LEM-2, another integral envelope protein, causes local changes in nuclear architecture as evidenced by altered association between DNA and LMN-1. Transcriptome analyses reveal that EMR-1 and LEM-2 are associated with gene repression, particularly of genes implicated in muscle and nervous system function. We demonstrate that emr-1, but not lem-2, mutants are sensitive to the cholinesterase inhibitor aldicarb, indicating altered activity at neuromuscular junctions. Conclusions We identify a class of elements that bind EMR-1 but do not associate with LMN-1, and these are enriched for muscle and neuronal genes. Our data support a redundant function of EMR-1 and LEM-2 in chromatin anchoring to the nuclear envelope and gene repression. We demonstrate a specific role of EMR-1 in neuromuscular junction activity that may contribute to Emery-Dreifuss muscular dystrophy in humans. PMID:24490688

  20. Genome-wide analysis of LXRα activation reveals new transcriptional networks in human atherosclerotic foam cells.

    PubMed

    Feldmann, Radmila; Fischer, Cornelius; Kodelja, Vitam; Behrens, Sarah; Haas, Stefan; Vingron, Martin; Timmermann, Bernd; Geikowski, Anne; Sauer, Sascha

    2013-04-01

    Increased physiological levels of oxysterols are major risk factors for developing atherosclerosis and cardiovascular disease. Lipid-loaded macrophages, termed foam cells, are important during the early development of atherosclerotic plaques. To pursue the hypothesis that ligand-based modulation of the nuclear receptor LXRα is crucial for cell homeostasis during atherosclerotic processes, we analysed genome-wide the action of LXRα in foam cells and macrophages. By integrating chromatin immunoprecipitation-sequencing (ChIP-seq) and gene expression profile analyses, we generated a highly stringent set of 186 LXRα target genes. Treatment with the nanomolar-binding ligand T0901317 and subsequent auto-regulatory LXRα activation resulted in sequence-dependent sharpening of the genome-binding patterns of LXRα. LXRα-binding loci that correlated with differential gene expression revealed 32 novel target genes with potential beneficial effects, which in part explained the implications of disease-associated genetic variation data. These observations identified highly integrated LXRα ligand-dependent transcriptional networks, including the APOE/C1/C4/C2-gene cluster, which contribute to the reversal of cholesterol efflux and the dampening of inflammation processes in foam cells to prevent atherogenesis.

  1. Wide-temperature range operation supercapacitors from nanostructured activated carbon fabric

    NASA Astrophysics Data System (ADS)

    Hung, Kaihsuan; Masarapu, Charan; Ko, Tsehao; Wei, Bingqing

    Electrochemical power sources that offer high energy and power densities and, can also withstand a harsh temperature range have become extremely desirable in applications ranging from civilian portable electronic devices to military weapons. In this report, we demonstrated a wide temperature withstanding supercapacitor which can be operated from 100 °C to -40 °C within a voltage window from -2 V to 2 V. The performance of the supercapacitor coin cells, assembled with nanostructured activated carbon fabric (ACF) as the electrode material and 1 M tetraethylammonium tetrafluoroborate (TEABF 4) in polypropylene carbonate (PC) solution as the electrolyte, was systematically studied within the set temperature window. The ACF supercapacitor yielded ideal rectangular shapes in cyclic voltammograms within 0-100 °C with an average mass capacitance of 90 F g -1 and, 60 F g -1 at -25 °C. The capacitance was still over 20 F g -1 at the extremely low temperature of -40 °C. Another exciting feature of the ACF supercapacitors was that they resumed their room temperature capacitance when cooled from 100 °C and defrosted from -40 °C, demonstrating an excellent repeatability and stability. The charge-discharge behavior of the ACF supercapacitors showed long-cycle stability at extreme temperatures. These high electrochemical performances make this type of supercapacitors very promising in many practical applications.

  2. Creative Activities in Music – A Genome-Wide Linkage Analysis

    PubMed Central

    Oikkonen, Jaana; Kuusi, Tuire; Peltonen, Petri; Raijas, Pirre; Ukkola-Vuoti, Liisa; Karma, Kai; Onkamo, Päivi; Järvelä, Irma

    2016-01-01

    Creative activities in music represent a complex cognitive function of the human brain, whose biological basis is largely unknown. In order to elucidate the biological background of creative activities in music we performed genome-wide linkage and linkage disequilibrium (LD) scans in musically experienced individuals characterised for self-reported composing, arranging and non-music related creativity. The participants consisted of 474 individuals from 79 families, and 103 sporadic individuals. We found promising evidence for linkage at 16p12.1-q12.1 for arranging (LOD 2.75, 120 cases), 4q22.1 for composing (LOD 2.15, 103 cases) and Xp11.23 for non-music related creativity (LOD 2.50, 259 cases). Surprisingly, statistically significant evidence for linkage was found for the opposite phenotype of creative activity in music (neither composing nor arranging; NCNA) at 18q21 (LOD 3.09, 149 cases), which contains cadherin genes like CDH7 and CDH19. The locus at 4q22.1 overlaps the previously identified region of musical aptitude, music perception and performance giving further support for this region as a candidate region for broad range of music-related traits. The other regions at 18q21 and 16p12.1-q12.1 are also adjacent to the previously identified loci with musical aptitude. Pathway analysis of the genes suggestively associated with composing suggested an overrepresentation of the cerebellar long-term depression pathway (LTD), which is a cellular model for synaptic plasticity. The LTD also includes cadherins and AMPA receptors, whose component GSG1L was linked to arranging. These results suggest that molecular pathways linked to memory and learning via LTD affect music-related creative behaviour. Musical creativity is a complex phenotype where a common background with musicality and intelligence has been proposed. Here, we implicate genetic regions affecting music-related creative behaviour, which also include genes with neuropsychiatric associations. We also propose

  3. Creative Activities in Music--A Genome-Wide Linkage Analysis.

    PubMed

    Oikkonen, Jaana; Kuusi, Tuire; Peltonen, Petri; Raijas, Pirre; Ukkola-Vuoti, Liisa; Karma, Kai; Onkamo, Päivi; Järvelä, Irma

    2016-01-01

    Creative activities in music represent a complex cognitive function of the human brain, whose biological basis is largely unknown. In order to elucidate the biological background of creative activities in music we performed genome-wide linkage and linkage disequilibrium (LD) scans in musically experienced individuals characterised for self-reported composing, arranging and non-music related creativity. The participants consisted of 474 individuals from 79 families, and 103 sporadic individuals. We found promising evidence for linkage at 16p12.1-q12.1 for arranging (LOD 2.75, 120 cases), 4q22.1 for composing (LOD 2.15, 103 cases) and Xp11.23 for non-music related creativity (LOD 2.50, 259 cases). Surprisingly, statistically significant evidence for linkage was found for the opposite phenotype of creative activity in music (neither composing nor arranging; NCNA) at 18q21 (LOD 3.09, 149 cases), which contains cadherin genes like CDH7 and CDH19. The locus at 4q22.1 overlaps the previously identified region of musical aptitude, music perception and performance giving further support for this region as a candidate region for broad range of music-related traits. The other regions at 18q21 and 16p12.1-q12.1 are also adjacent to the previously identified loci with musical aptitude. Pathway analysis of the genes suggestively associated with composing suggested an overrepresentation of the cerebellar long-term depression pathway (LTD), which is a cellular model for synaptic plasticity. The LTD also includes cadherins and AMPA receptors, whose component GSG1L was linked to arranging. These results suggest that molecular pathways linked to memory and learning via LTD affect music-related creative behaviour. Musical creativity is a complex phenotype where a common background with musicality and intelligence has been proposed. Here, we implicate genetic regions affecting music-related creative behaviour, which also include genes with neuropsychiatric associations. We also propose

  4. Linking brain-wide multivoxel activation patterns to behaviour: Examples from language and math.

    PubMed

    Raizada, Rajeev D S; Tsao, Feng-Ming; Liu, Huei-Mei; Holloway, Ian D; Ansari, Daniel; Kuhl, Patricia K

    2010-05-15

    A key goal of cognitive neuroscience is to find simple and direct connections between brain and behaviour. However, fMRI analysis typically involves choices between many possible options, with each choice potentially biasing any brain-behaviour correlations that emerge. Standard methods of fMRI analysis assess each voxel individually, but then face the problem of selection bias when combining those voxels into a region-of-interest, or ROI. Multivariate pattern-based fMRI analysis methods use classifiers to analyse multiple voxels together, but can also introduce selection bias via data-reduction steps as feature selection of voxels, pre-selecting activated regions, or principal components analysis. We show here that strong brain-behaviour links can be revealed without any voxel selection or data reduction, using just plain linear regression as a classifier applied to the whole brain at once, i.e. treating each entire brain volume as a single multi-voxel pattern. The brain-behaviour correlations emerged despite the fact that the classifier was not provided with any information at all about subjects' behaviour, but instead was given only the neural data and its condition-labels. Surprisingly, more powerful classifiers such as a linear SVM and regularised logistic regression produce very similar results. We discuss some possible reasons why the very simple brain-wide linear regression model is able to find correlations with behaviour that are as strong as those obtained on the one hand from a specific ROI and on the other hand from more complex classifiers. In a manner which is unencumbered by arbitrary choices, our approach offers a method for investigating connections between brain and behaviour which is simple, rigorous and direct.

  5. Activity Patterns of Eurasian Lynx Are Modulated by Light Regime and Individual Traits over a Wide Latitudinal Range

    PubMed Central

    Heurich, Marco; Hilger, Anton; Küchenhoff, Helmut; Andrén, Henrik; Bufka, Luděk; Krofel, Miha; Mattisson, Jenny; Odden, John; Persson, Jens; Rauset, Geir R.; Schmidt, Krzysztof; Linnell, John D. C.

    2014-01-01

    The activity patterns of most terrestrial animals are regarded as being primarily influenced by light, although other factors, such as sexual cycle and climatic conditions, can modify the underlying patterns. However, most activity studies have been limited to a single study area, which in turn limit the variability of light conditions and other factors. Here we considered a range of variables that might potentially influence the activity of a large carnivore, the Eurasian lynx, in a network of studies conducted with identical methodology in different areas spanning latitudes from 49°7′N in central Europe to 70°00′N in northern Scandinavia. The variables considered both light conditions, ranging from a day with a complete day–night cycle to polar night and polar day, as well as individual traits of the animals. We analysed activity data of 38 individual free-ranging lynx equipped with GPS-collars with acceleration sensors, covering more than 11,000 lynx days. Mixed linear additive models revealed that the lynx activity level was not influenced by the daily daylight duration and the activity pattern was bimodal, even during polar night and polar day. The duration of the active phase of the activity cycle varied with the widening and narrowing of the photoperiod. Activity varied significantly with moonlight. Among adults, males were more active than females, and subadult lynx were more active than adults. In polar regions, the amplitude of the lynx daily activity pattern was low, likely as a result of the polycyclic activity pattern of their main prey, reindeer. At lower latitudes, the basic lynx activity pattern peaked during twilight, corresponding to the crepuscular activity pattern of the main prey, roe deer. Our results indicated that the basic activity of lynx is independent of light conditions, but is modified by both individual traits and the activity pattern of the locally most important prey. PMID:25517902

  6. Activity patterns of Eurasian lynx are modulated by light regime and individual traits over a wide latitudinal range.

    PubMed

    Heurich, Marco; Hilger, Anton; Küchenhoff, Helmut; Andrén, Henrik; Bufka, Luděk; Krofel, Miha; Mattisson, Jenny; Odden, John; Persson, Jens; Rauset, Geir R; Schmidt, Krzysztof; Linnell, John D C

    2014-01-01

    The activity patterns of most terrestrial animals are regarded as being primarily influenced by light, although other factors, such as sexual cycle and climatic conditions, can modify the underlying patterns. However, most activity studies have been limited to a single study area, which in turn limit the variability of light conditions and other factors. Here we considered a range of variables that might potentially influence the activity of a large carnivore, the Eurasian lynx, in a network of studies conducted with identical methodology in different areas spanning latitudes from 49°7'N in central Europe to 70°00'N in northern Scandinavia. The variables considered both light conditions, ranging from a day with a complete day-night cycle to polar night and polar day, as well as individual traits of the animals. We analysed activity data of 38 individual free-ranging lynx equipped with GPS-collars with acceleration sensors, covering more than 11,000 lynx days. Mixed linear additive models revealed that the lynx activity level was not influenced by the daily daylight duration and the activity pattern was bimodal, even during polar night and polar day. The duration of the active phase of the activity cycle varied with the widening and narrowing of the photoperiod. Activity varied significantly with moonlight. Among adults, males were more active than females, and subadult lynx were more active than adults. In polar regions, the amplitude of the lynx daily activity pattern was low, likely as a result of the polycyclic activity pattern of their main prey, reindeer. At lower latitudes, the basic lynx activity pattern peaked during twilight, corresponding to the crepuscular activity pattern of the main prey, roe deer. Our results indicated that the basic activity of lynx is independent of light conditions, but is modified by both individual traits and the activity pattern of the locally most important prey.

  7. Varying behavior of different window sizes on the classification of static and dynamic physical activities from a single accelerometer.

    PubMed

    Fida, Benish; Bernabucci, Ivan; Bibbo, Daniele; Conforto, Silvia; Schmid, Maurizio

    2015-07-01

    Accuracy of systems able to recognize in real time daily living activities heavily depends on the processing step for signal segmentation. So far, windowing approaches are used to segment data and the window size is usually chosen based on previous studies. However, literature is vague on the investigation of its effect on the obtained activity recognition accuracy, if both short and long duration activities are considered. In this work, we present the impact of window size on the recognition of daily living activities, where transitions between different activities are also taken into account. The study was conducted on nine participants who wore a tri-axial accelerometer on their waist and performed some short (sitting, standing, and transitions between activities) and long (walking, stair descending and stair ascending) duration activities. Five different classifiers were tested, and among the different window sizes, it was found that 1.5 s window size represents the best trade-off in recognition among activities, with an obtained accuracy well above 90%. Differences in recognition accuracy for each activity highlight the utility of developing adaptive segmentation criteria, based on the duration of the activities.

  8. UTILITY OF A WIDE SPECTRUM LIGHT METER AS AN UNDERWATER SENSOR OF PHOTOSYNTHETICALLY ACTIVE RADIATION (PAR)

    EPA Science Inventory

    The strong attenuation of infra red wavelengths (>700 nm) in coastal waters is suggestive that some instruments with broad spectral responses might be useful, inexpensive substitutes for PAR sensors in studies of estuarine plant dynamics. Wide spectrum (350-1100 nm) light intensi...

  9. The antiviral and antimicrobial activities of licorice, a widely-used Chinese herb

    PubMed Central

    Wang, Liqiang; Yang, Rui; Yuan, Bochuan; Liu, Ying; Liu, Chunsheng

    2015-01-01

    Licorice is a common herb which has been used in traditional Chinese medicine for centuries. More than 20 triterpenoids and nearly 300 flavonoids have been isolated from licorice. Recent studies have shown that these metabolites possess many pharmacological activities, such as antiviral, antimicrobial, anti-inflammatory, antitumor and other activities. This paper provides a summary of the antiviral and antimicrobial activities of licorice. The active components and the possible mechanisms for these activities are summarized in detail. This review will be helpful for the further studies of licorice for its potential therapeutic effects as an antiviral or an antimicrobial agent. PMID:26579460

  10. Relative activity of cerebral subcortical gray matter in varying states of attention and awareness in normal subjects and patient studies

    SciTech Connect

    Cooper, M.; Chen, C.T.; Levy, J.; Wagner, N.; Spire, J.P.; Jacobsen, J.; Meltzer, H.; Metz, J.; Beck, R.N.

    1985-05-01

    An important aspect of the study of brain function involves measurement of the relationships; between activities in the subcortical gray matter of the caudate and of the thalamus; and between these structures and functional cortical areas. The authors have studied these relationships in 22 subjects under different conditions of activation, sleep and sensory deprivation using a PET VI system and F-18-2DG to determine regional cerebral metabolism. Subject activating conditions were maintained throughout the period of equilibration of F-18-2DG and E.E.G.'s were monitored. Multiple tomographic slices of 1-2 million counts were obtained simultaneously with slice separation of 14mm and each plane parallel to the cantho-meatal line. In activated and non-activated awake conditions for normal subjects, left and right thalmus-to-caudate ratios were similar and greater than unity. This relationship was maintained in non-REM sleep, but was reversed and divergent in REM sleep and sensory deprivation; this was also evident in 3/4 narcoleptics awake and asleep in non-REM and REM and 2/3 schizophrenics and affective disorder, subjects. This approach appears to have potential for characterizating normal and disordered regional cerebral function.

  11. Fire Activity and Severity in the Western US Vary along Proxy Gradients Representing Fuel Amount and Fuel Moisture

    PubMed Central

    Parks, Sean A.; Parisien, Marc-André; Miller, Carol; Dobrowski, Solomon Z.

    2014-01-01

    Numerous theoretical and empirical studies have shown that wildfire activity (e.g., area burned) at regional to global scales may be limited at the extremes of environmental gradients such as productivity or moisture. Fire activity, however, represents only one component of the fire regime, and no studies to date have characterized fire severity along such gradients. Given the importance of fire severity in dictating ecological response to fire, this is a considerable knowledge gap. For the western US, we quantify relationships between climate and the fire regime by empirically describing both fire activity and severity along two climatic water balance gradients, actual evapotranspiration (AET) and water deficit (WD), that can be considered proxies for fuel amount and fuel moisture, respectively. We also concurrently summarize fire activity and severity among ecoregions, providing an empirically based description of the geographic distribution of fire regimes. Our results show that fire activity in the western US increases with fuel amount (represented by AET) but has a unimodal (i.e., humped) relationship with fuel moisture (represented by WD); fire severity increases with fuel amount and fuel moisture. The explicit links between fire regime components and physical environmental gradients suggest that multivariable statistical models can be generated to produce an empirically based fire regime map for the western US. Such models will potentially enable researchers to anticipate climate-mediated changes in fire recurrence and its impacts based on gridded spatial data representing future climate scenarios. PMID:24941290

  12. Fire activity and severity in the western US vary along proxy gradients representing fuel amount and fuel moisture.

    PubMed

    Parks, Sean A; Parisien, Marc-André; Miller, Carol; Dobrowski, Solomon Z

    2014-01-01

    Numerous theoretical and empirical studies have shown that wildfire activity (e.g., area burned) at regional to global scales may be limited at the extremes of environmental gradients such as productivity or moisture. Fire activity, however, represents only one component of the fire regime, and no studies to date have characterized fire severity along such gradients. Given the importance of fire severity in dictating ecological response to fire, this is a considerable knowledge gap. For the western US, we quantify relationships between climate and the fire regime by empirically describing both fire activity and severity along two climatic water balance gradients, actual evapotranspiration (AET) and water deficit (WD), that can be considered proxies for fuel amount and fuel moisture, respectively. We also concurrently summarize fire activity and severity among ecoregions, providing an empirically based description of the geographic distribution of fire regimes. Our results show that fire activity in the western US increases with fuel amount (represented by AET) but has a unimodal (i.e., humped) relationship with fuel moisture (represented by WD); fire severity increases with fuel amount and fuel moisture. The explicit links between fire regime components and physical environmental gradients suggest that multivariable statistical models can be generated to produce an empirically based fire regime map for the western US. Such models will potentially enable researchers to anticipate climate-mediated changes in fire recurrence and its impacts based on gridded spatial data representing future climate scenarios.

  13. Measuring hospital-wide activity volume for patient safety and infection control: a multi-centre study in Japan

    PubMed Central

    Hayashida, Kenshi; Imanaka, Yuichi; Fukuda, Haruhisa

    2007-01-01

    Background In Japan, as in many other countries, several quality and safety assurance measures have been implemented since the 1990's. This has occurred in spite of cost containment efforts. Although government and hospital decision-makers demand comprehensive analysis of these activities at the hospital-wide level, there have been few studies that actually quantify them. Therefore, the aims of this study were to measure hospital-wide activities for patient safety and infection control through a systematic framework, and to identify the incremental volume of these activities implemented over the last five years. Methods Using the conceptual framework of incremental activity corresponding to incremental cost, we defined the scope of patient safety and infection control activities. We then drafted a questionnaire to analyze these realms. After implementing the questionnaire, we conducted several in-person interviews with managers and other staff in charge of patient safety and infection control in seven acute care teaching hospitals in Japan. Results At most hospitals, nurses and clerical employees acted as the main figures in patient safety practices. The annual amount of activity ranged from 14,557 to 72,996 person-hours (per 100 beds: 6,240; per 100 staff: 3,323) across participant hospitals. Pharmacists performed more incremental activities than their proportional share. With respect to infection control activities, the annual volume ranged from 3,015 to 12,196 person-hours (per 100 beds: 1,141; per 100 staff: 613). For infection control, medical doctors and nurses tended to perform somewhat more of the duties relative to their share. Conclusion We developed a systematic framework to quantify hospital-wide activities for patient safety and infection control. We also assessed the incremental volume of these activities in Japanese hospitals under the reimbursement containment policy. Government and hospital decision makers can benefit from this type of analytic

  14. Contextualized Approach to Language and Literacy (Project CALL): Capitalizing on Varied Activities and Contexts to Teach Early Literacy Skills

    ERIC Educational Resources Information Center

    Culatta, Barbara; Hall, Kendra; Kovarsky, Dana; Theadore, Geraldine

    2007-01-01

    In a federally funded early literacy project, various instructional activities were embedded into an array of classroom contexts to provide supplemental literacy instruction and to contrast children's engagement and participation in different contexts and participant structures. The study was conducted with English- and Spanish-speaking children…

  15. Leisure-Time Physical Activity, Sedentary Behavior, and Physical Fitness among Adolescents: Varying Definitions Yield Differing Results in Fitness Research

    ERIC Educational Resources Information Center

    Kerner, Matthew S.

    2005-01-01

    The aims of the study were (1) to assess the relationships among leisure-time physical activity, sedentary behaviors, and measures of health-related and performance-related physical fitness, and (2) to determine the primary predictors of performance-related physical fitness from the variables investigated. This study updates the literature with…

  16. Effect of using repurposed science-rich feature films with varying levels of student activity in middle grades science instruction

    NASA Astrophysics Data System (ADS)

    Cavanaugh, Terence William

    This study provided an initial investigation into the use of repurposed content-rich entertainment videos (versus traditional educational videos) presented in either an active or passive educational setting. Eight classes of seventh grade general science students (n = 361) were randomly assigned to one of four video treatment groups: (1) repurposed content-rich entertainment video in a passive setting, (2) repurposed content-rich entertainment video in an active setting, (3) traditional educational video in a passive setting, and (4) traditional educational video in an active setting. The subject matter of the videos focused on basic chemistry, scientific method, and the nature of life. The repurposed content-rich entertainment groups watched a StarTrek the Next Generation episode, and the traditional educational video groups watched videos from NASA and the Understanding Science Corporation. Students completed a knowledge-based pretest and an initial attitude survey prior to the treatment. During the treatment, all participants watched the videos, discussed the science content, and answered directed questions. Active setting groups discussed and answered questions during the video, while the passive setting groups discussed and answered questions after the video. The treatment period lasted approximately 135 minutes. Immediately following treatment, participants received a knowledge-based posttest and an attitude survey. Three weeks after treatment, retention tests and follow-up surveys were administered. Test and survey data were analyzed using single factor and repeated measures ANOVA followed by post hoc tests. Significant gains (p < 0.05) in test scores were found for repurposed content-rich entertainment video over traditional educational video groups. No significant differences were found in test scores between the active and passive setting groups. When the variables were combined, additional effects were noted. Specifically, significant differences were

  17. A Genome-Wide Association Study of Amygdala Activation in Youths with and without Bipolar Disorder

    ERIC Educational Resources Information Center

    Liu, Xinmin; Akula, Nirmala; Skup, Martha; Brotman, Melissa A.; Leibenluft, Ellen; McMahon, Francis J.

    2010-01-01

    Objective: Functional magnetic resonance imaging is commonly used to characterize brain activity underlying a variety of psychiatric disorders. A previous functional magnetic resonance imaging study found that amygdala activation during a face-processing task differed between pediatric patients with bipolar disorder (BD) and healthy controls. We…

  18. An Evaluation of a Wide Range of Job-Generating Activities for Rural Counties.

    ERIC Educational Resources Information Center

    Finsterbusch, Kurt; And Others

    1992-01-01

    Examines the job-generating activities in 15 rural counties in Maryland through 175 interviews and field work. Those ranking high included industrial park development, economic development activities, and tourism. Special financial arrangements for relocating and new businesses also received high marks. Includes 48 references. (JOW)

  19. Development of a precision, wide-dynamic-range actuator for use in active optical systems

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Aubrun, J-N.; Zacharie, D. F.; Perez, E. O.

    1989-01-01

    The design, operation, and performance of a wide-dynamic-range optical-quality actuator are discussed. The actuator uses a closed-loop control system to maintain accurate positioning and has an rms noise performance of 20 nm. A unique force offloading mechanism allows the actuator coil to dissipate less than 3 mW under quiescent conditions. The operation of an experimental segmented optical system that uses 18 of the actuators is examined to show how they are integrated into an actual system.

  20. Analysis of the locomotor activity of a nocturnal desert lizard (Reptilia: Gekkonidae: Teratoscincus scincus) under varying moonlight.

    PubMed

    Seligmann, Hervé; Anderson, Steven C; Autumn, Kellar; Bouskila, Amos; Saf, Rachel; Tuniyev, Boris S; Werner, Yehudah L

    2007-01-01

    1. This project seeks to identify determinants of the variation observed in the foraging behavior of predatory animals, especially in moonlight, using a lizard as a model. 2. Moonlight generally enhances the foraging efficiency of nocturnal visual predators and often depresses the locomotor activity of prey animals. Previous evidence has indicated for three different nocturnal species of smallish gecko lizards that they respond to moonlight by increasing their activity. 3. In this study some aspects of the foraging activity of the somewhat larger nocturnal psammophilous Teratoscincus scincus, observed near Repetek and Ashgabat, Turkmenistan, were significantly depressed by moonlight, while several confounding factors (sex, maturity, size, sand temperature, hour, prior handling and observer effect) were taken into account. 4. This behavioral difference may relate to the eye size of the various species. 5. Additionally, a novel method of analyzing foraging behavior shows that in this species the duration of moves increases the duration of subsequent stationary pauses. Measurement of locomotor speed, yielding an average speed of 220% of the maximum aerobic speed, indicates a need for these pauses. Secondarily, pause duration decreases the duration of subsequent moves, precluding escalation of move duration. 6. The results of this and related projects advocate the taking into account of physiological and environmental factors that may affect an animal's foraging behavior.

  1. Monolithically, widely tunable quantum cascade lasers based on a heterogeneous active region design

    PubMed Central

    Zhou, Wenjia; Bandyopadhyay, Neelanjan; Wu, Donghai; McClintock, Ryan; Razeghi, Manijeh

    2016-01-01

    Quantum cascade lasers (QCLs) have become important laser sources for accessing the mid-infrared (mid-IR) spectral range, achieving watt-level continuous wave operation in a compact package at room temperature. However, up to now, wavelength tuning, which is desirable for most applications, has relied on external cavity feedback or exhibited a limited monolithic tuning range. Here we demonstrate a widely tunable QCL source over the 6.2 to 9.1 μm wavelength range with a single emitting aperture by integrating an eight-laser sampled grating distributed feedback laser array with an on-chip beam combiner. The laser gain medium is based on a five-core heterogeneous QCL wafer. A compact tunable laser system was built to drive the individual lasers within the array and produce any desired wavelength within the available spectral range. A rapid, broadband spectral measurement (520 cm−1) of methane using the tunable laser source shows excellent agreement to a measurement made using a standard low-speed infrared spectrometer. This monolithic, widely tunable laser technology is compact, with no moving parts, and will open new opportunities for MIR spectroscopy and chemical sensing. PMID:27270634

  2. Learning and memory in the forced swimming test: effects of antidepressants having varying degrees of anticholinergic activity.

    PubMed

    Enginar, Nurhan; Yamantürk-Çelik, Pınar; Nurten, Asiye; Güney, Dilvin Berrak

    2016-07-01

    The antidepressant-induced reduction in immobility time in the forced swimming test may depend on memory impairment due to the drug's anticholinergic efficacy. Therefore, the present study evaluated learning and memory of the immobility response in rats after the pretest and test administrations of antidepressants having potent, comparatively lower, and no anticholinergic activities. Immobility was measured in the test session performed 24 h after the pretest session. Scopolamine and MK-801, which are agents that have memory impairing effects, were used as reference drugs for a better evaluation of the memory processes in the test. The pretest administrations of imipramine (15 and 30 mg/kg), amitriptyline (7.5 and 15 mg/kg), trazodone (10 mg/kg), fluoxetine (10 and 20 mg/kg), and moclobemide (10 and 20 mg/kg) were ineffective, whereas the pretest administrations of scopolamine (0.5 mg/kg) and MK-801 (0.1 mg/kg) decreased immobility time suggesting impaired "learning to be immobile" in the animals. The test administrations of imipramine (30 mg/kg), amitriptyline (15 mg/kg), moclobemide (10 mg/kg), scopolamine (0.5 and 1 mg/kg), and MK-801 (0.1 mg/kg) decreased immobility time, which suggested that the drugs exerted antidepressant activity or the animals did not recall that attempting to escape was futile. The test administrations of trazodone (10 mg/kg) and fluoxetine (10 and 20 mg/kg) produced no effect on immobility time. Even though the false-negative and positive responses made it somewhat difficult to interpret the findings, this study demonstrated that when given before the pretest antidepressants with or without anticholinergic activity seemed to be devoid of impairing the learning process in the test.

  3. Genome-Wide Association Study of Lp-PLA2 Activity and Mass in the Framingham Heart Study

    PubMed Central

    Suchindran, Sunil; Rivedal, David; Guyton, John R.; Milledge, Tom; Gao, Xiaoyi; Benjamin, Ashlee; Rowell, Jennifer; Ginsburg, Geoffrey S.; McCarthy, Jeanette J.

    2010-01-01

    Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an emerging risk factor and therapeutic target for cardiovascular disease. The activity and mass of this enzyme are heritable traits, but major genetic determinants have not been explored in a systematic, genome-wide fashion. We carried out a genome-wide association study of Lp-PLA2 activity and mass in 6,668 Caucasian subjects from the population-based Framingham Heart Study. Clinical data and genotypes from the Affymetrix 550K SNP array were obtained from the open-access Framingham SHARe project. Each polymorphism that passed quality control was tested for associations with Lp-PLA2 activity and mass using linear mixed models implemented in the R statistical package, accounting for familial correlations, and controlling for age, sex, smoking, lipid-lowering-medication use, and cohort. For Lp-PLA2 activity, polymorphisms at four independent loci reached genome-wide significance, including the APOE/APOC1 region on chromosome 19 (p = 6×10−24); CELSR2/PSRC1 on chromosome 1 (p = 3×10−15); SCARB1 on chromosome 12 (p = 1×10−8) and ZNF259/BUD13 in the APOA5/APOA1 gene region on chromosome 11 (p = 4×10−8). All of these remained significant after accounting for associations with LDL cholesterol, HDL cholesterol, or triglycerides. For Lp-PLA2 mass, 12 SNPs achieved genome-wide significance, all clustering in a region on chromosome 6p12.3 near the PLA2G7 gene. Our analyses demonstrate that genetic polymorphisms may contribute to inter-individual variation in Lp-PLA2 activity and mass. PMID:20442857

  4. Skin tumor-promoting activity of benzoyl peroxide, a widely used free radical-generating compound

    SciTech Connect

    Slaga, T.J.; Klein-Szanto, A.J.P.; Triplett, L.L.; Yotti, L.P.; Trosko, J.E.

    1981-08-28

    Benzoyl peroxide, a widely used free radical-generating compound, promoted both papillomas and carcinomas when it was topically applied to mice after 7, 12-dimethylbenz(a)anthracene initiation. Benzoyl peroxide was inactive on the skin as a complete carcinogen or as a tumor initiator. A single topical application of benzoyl peroxide produced a marked epidermal hyperplasia and induced a large number of dark basal keratinocytes, effects similar to those produced by the potent tumor promoter 12-O-tetradecanoyl phorbol-13-acetate. Benzoyl peroxide, like other known tumor promoters, also inhibited metabolic cooperation (intercellular communication) in Chinese hamster cells. In view of these results caution should be recommended in the use of this and other free radical-generating compounds.

  5. Regional and total body active heating and cooling of a resting diver in water of varied temperatures

    NASA Astrophysics Data System (ADS)

    Bardy, Erik; Mollendorf, Joseph; Pendergast, David

    2008-02-01

    Passive insulations alone are not sufficient for maintaining underwater divers in thermal balance or comfort. The purpose of this study was to experimentally determine the active heating and cooling requirements to keep a diver at rest in thermal balance and comfort in water temperatures between 10 and 40 °C. A diver wearing a prototype tubesuit and a wetsuit (3 or 6.5 mm foam neoprene) was fully submersed (0.6 m) in water at a specified temperature (10, 20, 30 and 40 °C). During immersion, the tubesuit was perfused with 30 °C water at a flow rate of 0.5 L min-1 to six individual body regions. An attempt was made to keep skin temperatures below 42 °C in hot water (>30 °C) and elevated but below 32 °C in cold water (<20 °C). A skin temperature of 32 °C is the threshold for maximal body thermal resistance due to vasoconstriction. Skin temperatures and core temperature were monitored during immersion to ensure they remained within set thermal limits. In addition skin heat flux, oxygen consumption and the thermal exchange of the tubesuit were measured. In both wetsuit thicknesses there was a linear correlation between the thermal exchange of the tubesuit and ambient water temperature. In the 6.5 mm wetsuit -214 W to 242 W of heating (-) and cooling (+) was necessary in 10 °C to 40 °C water, respectively. In the 3 mm wetsuit -462 to 342 W was necessary in 10 °C to 40 °C water, respectively. It was therefore concluded that a diver at rest can be kept in thermal balance in 10-40 °C water with active heating and cooling.

  6. Penicillium verruculosum SG: a source of polyketide and bioactive compounds with varying cytotoxic activities against normal and cancer lines.

    PubMed

    Shah, Salma Gul; Shier, W Thomas; Jamaluddin; Tahir, Nawaz; Hameed, Abdul; Ahmad, Safia; Ali, Naeem

    2014-04-01

    A newly isolated fungus Penicillium verruculosum SG was evaluated for the production and characterization of bioactive colored secondary metabolites using solid-state fermentation along with their cytotoxic activities against normal and cancer cell lines. Logical fragmentation pattern following column chromatography, thin layer chromatography and liquid chromatography and mass spectrometry of crude culture filtrate of fungus revealed the presence of different polyketide pigments and other bioactive compounds. Cytotoxicity of the selected colored fractions of fungal filtrate containing different compounds revealed IC50 (μg/ml) values ranging from 5 to 100. It was significantly higher in case of orevactaene (5 + 0.44) and monascorubrine followed by pyripyropene (8 + 0.63) against cancer cell line KA3IT. Overall, these compounds considerably showed less toxicity toward normal cell lines NIH3T3, HSCT6, HEK293 and MDCK. XRD of a yellow crystalline compound (224.21 m/z) confirmed its 3-dimensional structure as phenazine 1 carboxylic acid (C13H8N2O2) (broad spectrum antibiotic), and it is first time reported in fungi.

  7. Active fault detection and isolation of discrete-time linear time-varying systems: a set-membership approach

    NASA Astrophysics Data System (ADS)

    Mojtaba Tabatabaeipour, Seyed

    2015-08-01

    Active fault detection and isolation (AFDI) is used for detection and isolation of faults that are hidden in the normal operation because of a low excitation signal or due to the regulatory actions of the controller. In this paper, a new AFDI method based on set-membership approaches is proposed. In set-membership approaches, instead of a point-wise estimation of the states, a set-valued estimation of them is computed. If this set becomes empty the given model of the system is not consistent with the measurements. Therefore, the model is falsified. When more than one model of the system remains un-falsified, the AFDI method is used to generate an auxiliary signal that is injected into the system for detection and isolation of faults that remain otherwise hidden or non-isolated using passive FDI (PFDI) methods. Having the set-valued estimation of the states for each model, the proposed AFDI method finds an optimal input signal that guarantees FDI in a finite time horizon. The input signal is updated at each iteration in a decreasing receding horizon manner based on the set-valued estimation of the current states and un-falsified models at the current sample time. The problem is solved by a number of linear and quadratic programming problems, which result in a computationally efficient algorithm. The method is tested on a numerical example as well as on the pitch actuator of a benchmark wind turbine.

  8. The content of macro- and microelements and the phosphatase activity of soils under a varied plant cultivation technology

    NASA Astrophysics Data System (ADS)

    Bartkowiak, A.; Lemanowicz, J.; Kobierski, M.

    2015-12-01

    The paper presents the results of the analyses of selected physicochemical properties and the activity of alkaline and acid phosphatase in the soils which differed in terms of plant cultivation technology. Profile sI represented arable land in the crop rotation with cereals dominating (medium intensive technology), without irrigation, while profile sII—represented arable land with vegetable crops cultivation (intensive technology), intensively fertilized and irrigated. The content of available phosphorus in the two soil profiles investigated ranged from 6.6 to 69.1 mg/kg. The highest contents of phosphorus available to plants were reported in the plough horizon of both soils, while the abundance of potassium and magnesium was highest in the illuvial horizon of both soils. The soil profiles investigated showed a significant variation in terms of the cultivation technologies applied. The contents of plant-available Cu and Zn in soil were low and they resulted in the inhibition of neither alkaline nor acid phosphatase. The intensive vegetable crops cultivation technology decreased the content of organic matter and increased the content of the nutrients in soil. Using the Ward method, it was found that relatively similar physicochemical and chemical properties were reported for the genetic horizons of both soil profiles, especially Ap horizon of the soil representing arable land with intensive cultivation of vegetable crops.

  9. 15 CFR 922.72 - Prohibited or otherwise regulated activities-Sanctuary-wide.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) Discharging or depositing from beyond the boundary of the Sanctuary any material or other matter that... in or resulting from lawful fishing activity beyond the boundary of the Sanctuary, provided that such... otherwise altering the submerged lands of the Sanctuary; or constructing or placing any structure,...

  10. 15 CFR 922.72 - Prohibited or otherwise regulated activities-Sanctuary-wide.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... OCEAN AND COASTAL RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Channel Islands... discharge or deposit is during the conduct of lawful fishing activity there. (4) Drilling into, dredging, or... carriers and barges, any vessel engaged in the trade of servicing offshore installations, or any vessel...

  11. 15 CFR 922.72 - Prohibited or otherwise regulated activities-Sanctuary-wide.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... OCEAN AND COASTAL RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Channel Islands... discharge or deposit is during the conduct of lawful fishing activity there. (4) Drilling into, dredging, or... carriers and barges, any vessel engaged in the trade of servicing offshore installations, or any vessel...

  12. 15 CFR 922.72 - Prohibited or otherwise regulated activities-Sanctuary-wide.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OCEAN AND COASTAL RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Channel Islands... discharge or deposit is during the conduct of lawful fishing activity there. (4) Drilling into, dredging, or... carriers and barges, any vessel engaged in the trade of servicing offshore installations, or any vessel...

  13. Multistability of memristive Cohen-Grossberg neural networks with non-monotonic piecewise linear activation functions and time-varying delays.

    PubMed

    Nie, Xiaobing; Zheng, Wei Xing; Cao, Jinde

    2015-11-01

    The problem of coexistence and dynamical behaviors of multiple equilibrium points is addressed for a class of memristive Cohen-Grossberg neural networks with non-monotonic piecewise linear activation functions and time-varying delays. By virtue of the fixed point theorem, nonsmooth analysis theory and other analytical tools, some sufficient conditions are established to guarantee that such n-dimensional memristive Cohen-Grossberg neural networks can have 5(n) equilibrium points, among which 3(n) equilibrium points are locally exponentially stable. It is shown that greater storage capacity can be achieved by neural networks with the non-monotonic activation functions introduced herein than the ones with Mexican-hat-type activation function. In addition, unlike most existing multistability results of neural networks with monotonic activation functions, those obtained 3(n) locally stable equilibrium points are located both in saturated regions and unsaturated regions. The theoretical findings are verified by an illustrative example with computer simulations.

  14. High spatial and temporal resolution wide-field imaging of neuron activity using quantum NV-diamond.

    PubMed

    Hall, L T; Beart, G C G; Thomas, E A; Simpson, D A; McGuinness, L P; Cole, J H; Manton, J H; Scholten, R E; Jelezko, F; Wrachtrup, Jörg; Petrou, S; Hollenberg, L C L

    2012-01-01

    A quantitative understanding of the dynamics of biological neural networks is fundamental to gaining insight into information processing in the brain. While techniques exist to measure spatial or temporal properties of these networks, it remains a significant challenge to resolve the neural dynamics with subcellular spatial resolution. In this work we consider a fundamentally new form of wide-field imaging for neuronal networks based on the nanoscale magnetic field sensing properties of optically active spins in a diamond substrate. We analyse the sensitivity of the system to the magnetic field generated by an axon transmembrane potential and confirm these predictions experimentally using electronically-generated neuron signals. By numerical simulation of the time dependent transmembrane potential of a morphologically reconstructed hippocampal CA1 pyramidal neuron, we show that the imaging system is capable of imaging planar neuron activity non-invasively at millisecond temporal resolution and micron spatial resolution over wide-fields.

  15. Germ-Line Recombination Activity of the Widely Used hGFAP-Cre and Nestin-Cre Transgenes

    PubMed Central

    Zhang, Jiong; Dublin, Pavel; Griemsmann, Stephanie; Klein, Alexandra; Brehm, Ralph; Bedner, Peter; Fleischmann, Bernd K.; Steinhäuser, Christian; Theis, Martin

    2013-01-01

    Herein we demonstrate with PCR, immunodetection and reporter gene approaches that the widely used human Glial Fibrillary Acidic Protein (hGFAP)-Cre transgene exhibits spontaneous germ-line recombination activity in leading to deletion in brain, heart and tail tissue with high frequency. The ectopic activity of hGFAP-Cre requires a rigorous control. We likewise observed that a second widely used nestin-Cre transgene shows germ-line deletion. Here we describe procedures to identify mice with germ-line recombination mediated by the hGFAP-Cre and nestin-Cre transgenes. Such control is essential to avoid pleiotropic effects due to germ-line deletion of loxP-flanked target genes and to maintain the CNS-restricted deletion status in transgenic mouse colonies. PMID:24349371

  16. Piezo activated mode tracking system for widely tunable mode-hop-free external cavity mid-IR semiconductor lasers

    NASA Technical Reports Server (NTRS)

    Wysocki, Gerard (Inventor); Tittel, Frank K. (Inventor); Curl, Robert F. (Inventor)

    2010-01-01

    A widely tunable, mode-hop-free semiconductor laser operating in the mid-IR comprises a QCL laser chip having an effective QCL cavity length, a diffraction grating defining a grating angle and an external cavity length with respect to said chip, and means for controlling the QCL cavity length, the external cavity length, and the grating angle. The laser of claim 1 wherein said chip may be tuned over a range of frequencies even in the absence of an anti-reflective coating. The diffraction grating is controllably pivotable and translatable relative to said chip and the effective QCL cavity length can be adjusted by varying the injection current to the chip. The laser can be used for high resolution spectroscopic applications and multi species trace-gas detection. Mode-hopping is avoided by controlling the effective QCL cavity length, the external cavity length, and the grating angle so as to replicate a virtual pivot point.

  17. Systems-wide analysis of manganese deficiency-induced changes in gene activity of Arabidopsis roots

    PubMed Central

    Rodríguez-Celma, Jorge; Tsai, Yi-Hsiu; Wen, Tuan-Nan; Wu, Yu-Ching; Curie, Catherine; Schmidt, Wolfgang

    2016-01-01

    Manganese (Mn) is pivotal for plant growth and development, but little information is available regarding the strategies that evolved to improve Mn acquisition and cellular homeostasis of Mn. Using an integrated RNA-based transcriptomic and high-throughput shotgun proteomics approach, we generated a comprehensive inventory of transcripts and proteins that showed altered abundance in response to Mn deficiency in roots of the model plant Arabidopsis. A suite of 22,385 transcripts was consistently detected in three RNA-seq runs; LC-MS/MS-based iTRAQ proteomics allowed the unambiguous determination of 11,606 proteins. While high concordance between mRNA and protein expression (R = 0.87) was observed for transcript/protein pairs in which both gene products accumulated differentially upon Mn deficiency, only approximately 10% of the total alterations in the abundance of proteins could be attributed to transcription, indicating a large impact of protein-level regulation. Differentially expressed genes spanned a wide range of biological functions, including the maturation, translation, and transport of mRNAs, as well as primary and secondary metabolic processes. Metabolic analysis by UPLC-qTOF-MS revealed that the steady-state levels of several major glucosinolates were significantly altered upon Mn deficiency in both roots and leaves, possibly as a compensation for increased pathogen susceptibility under conditions of Mn deficiency. PMID:27804982

  18. Development of an advanced pitch active control system for a wide body jet aircraft

    NASA Technical Reports Server (NTRS)

    Guinn, Wiley A.; Rising, Jerry J.; Davis, Walt J.

    1984-01-01

    An advanced PACS control law was developed for a commercial wide-body transport (Lockheed L-1011) by using modern control theory. Validity of the control law was demonstrated by piloted flight simulation tests on the NASA Langley visual motion simulator. The PACS design objective was to develop a PACS that would provide good flying qualities to negative 10 percent static stability margins that were equivalent to those of the baseline aircraft at a 15 percent static stability margin which is normal for the L-1011. Also, the PACS was to compensate for high-Mach/high-g instabilities that degrade flying qualities during upset recoveries and maneuvers. The piloted flight simulation tests showed that the PACS met the design objectives. The simulation demonstrated good flying qualities to negative 20 percent static stability margins for hold, cruise and high-speed flight conditions. Analysis and wind tunnel tests performed on other Lockheed programs indicate that the PACS could be used on an advanced transport configuration to provide a 4 percent fuel savings which results from reduced trim drag by flying at negative static stability margins.

  19. Genome-wide association study implicates immune activation of multiple integrin genes in inflammatory bowel disease.

    PubMed

    de Lange, Katrina M; Moutsianas, Loukas; Lee, James C; Lamb, Christopher A; Luo, Yang; Kennedy, Nicholas A; Jostins, Luke; Rice, Daniel L; Gutierrez-Achury, Javier; Ji, Sun-Gou; Heap, Graham; Nimmo, Elaine R; Edwards, Cathryn; Henderson, Paul; Mowat, Craig; Sanderson, Jeremy; Satsangi, Jack; Simmons, Alison; Wilson, David C; Tremelling, Mark; Hart, Ailsa; Mathew, Christopher G; Newman, William G; Parkes, Miles; Lees, Charlie W; Uhlig, Holm; Hawkey, Chris; Prescott, Natalie J; Ahmad, Tariq; Mansfield, John C; Anderson, Carl A; Barrett, Jeffrey C

    2017-02-01

    Genetic association studies have identified 215 risk loci for inflammatory bowel disease, thereby uncovering fundamental aspects of its molecular biology. We performed a genome-wide association study of 25,305 individuals and conducted a meta-analysis with published summary statistics, yielding a total sample size of 59,957 subjects. We identified 25 new susceptibility loci, 3 of which contain integrin genes that encode proteins in pathways that have been identified as important therapeutic targets in inflammatory bowel disease. The associated variants are correlated with expression changes in response to immune stimulus at two of these genes (ITGA4 and ITGB8) and at previously implicated loci (ITGAL and ICAM1). In all four cases, the expression-increasing allele also increases disease risk. We also identified likely causal missense variants in a gene implicated in primary immune deficiency, PLCG2, and a negative regulator of inflammation, SLAMF8. Our results demonstrate that new associations at common variants continue to identify genes relevant to therapeutic target identification and prioritization.

  20. Prion-Seeding Activity Is widely Distributed in Tissues of Sporadic Creutzfeldt-Jakob Disease Patients.

    PubMed

    Takatsuki, Hanae; Fuse, Takayuki; Nakagaki, Takehiro; Mori, Tsuyoshi; Mihara, Ban; Takao, Masaki; Iwasaki, Yasushi; Yoshida, Mari; Murayama, Shigeo; Atarashi, Ryuichiro; Nishida, Noriyuki; Satoh, Katsuya

    2016-10-01

    Human prion diseases are neurodegenerative disorders caused by abnormally folded prion proteins in the central nervous system. These proteins can be detected using the quaking-induced conversion assay. Compared with other bioassays, this assay is extremely sensitive and was used in the present study to determine prion distribution in sporadic Creutzfeldt-Jakob disease patients at autopsy. Although infectivity of the sporadic form is thought to be restricted within the central nervous system, results showed that prion-seeding activities reach 10(6)/g from a 50% seeding dose in non-neuronal tissues, suggesting that prion-seeding activity exists in non-neural organs, and we suggested that non-neural tissues of 10(6)/g SD50 did not exist the infectivity.

  1. In vitro activities of a wide panel of antifungal drugs against various Scopulariopsis and Microascus species.

    PubMed

    Skóra, Magdalena; Bulanda, Małgorzata; Jagielski, Tomasz

    2015-09-01

    The in vitro activities of 11 antifungal drugs against 68 Scopulariopsis and Microascus strains were investigated. Amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, ketoconazole, miconazole, posaconazole, voriconazole, and ciclopirox showed no or poor antifungal effect. The best activities were exhibited by terbinafine and caspofungin, where the MIC and MEC (minimal effective concentration) ranges were 0.0313 to >16 μg/ml and 0.125 to 16 μg/ml, respectively. The MIC and MEC modes were both 1 µg/ml for terbinafine and caspofungin; the MIC50 and MEC50 were 1 µg/ml for both drugs, whereas the MIC90 and MEC90 were 4 µg/ml and 16 µg/ml, respectively.

  2. Genome-Wide Expression Profiling Identifies Type 1 Interferon Response Pathways in Active Tuberculosis

    PubMed Central

    Ottenhoff, Tom H. M.; Zhang, Mingzi M.; Wong, Hazel E. E.; Sahiratmadja, Edhyana; Khor, Chiea Chuen; Alisjahbana, Bachti; van Crevel, Reinout; Marzuki, Sangkot; Seielstad, Mark; van de Vosse, Esther; Hibberd, Martin L.

    2012-01-01

    Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb), remains the leading cause of mortality from a single infectious agent. Each year around 9 million individuals newly develop active TB disease, and over 2 billion individuals are latently infected with M.tb worldwide, thus being at risk of developing TB reactivation disease later in life. The underlying mechanisms and pathways of protection against TB in humans, as well as the dynamics of the host response to M.tb infection, are incompletely understood. We carried out whole-genome expression profiling on a cohort of TB patients longitudinally sampled along 3 time-points: during active infection, during treatment, and after completion of curative treatment. We identified molecular signatures involving the upregulation of type-1 interferon (α/β) mediated signaling and chronic inflammation during active TB disease in an Indonesian population, in line with results from two recent studies in ethnically and epidemiologically different populations in Europe and South Africa. Expression profiles were captured in neutrophil-depleted blood samples, indicating a major contribution of lymphocytes and myeloid cells. Expression of type-1 interferon (α/β) genes mediated was also upregulated in the lungs of M.tb infected mice and in infected human macrophages. In patients, the regulated gene expression-signature normalized during treatment, including the type-1 interferon mediated signaling and a concurrent opposite regulation of interferon-gamma. Further analysis revealed IL15RA, UBE2L6 and GBP4 as molecules involved in the type-I interferon response in all three experimental models. Our data is highly suggestive that the innate immune type-I interferon signaling cascade could be used as a quantitative tool for monitoring active TB disease, and provide evidence that components of the patient’s blood gene expression signature bear similarities to the pulmonary and macrophage response to mycobacterial infection

  3. Synthesis and photocatalytic activity of perovskite niobium oxynitrides with wide visible-light absorption bands.

    PubMed

    Siritanaratkul, Bhavin; Maeda, Kazuhiko; Hisatomi, Takashi; Domen, Kazunari

    2011-01-17

    Photocatalytic activities of perovskite-type niobium oxynitrides (CaNbO₂N, SrNbO₂N, BaNbO₂N, and LaNbON₂) were examined for hydrogen and oxygen evolution from water under visible-light irradiation. These niobium oxynitrides were prepared by heating the corresponding oxide precursors, which were synthesized using the polymerized complex method, for 15 h under a flow of ammonia. They possess visible-light absorption bands between 600-750 nm, depending on the A-site cations in the structures. The oxynitride CaNbO₂N, was found to be active for hydrogen and oxygen evolution from methanol and aqueous AgNO₃, respectively, even under irradiation by light at long wavelengths (λ<560 nm). The nitridation temperature dependence of CaNbO₂N was investigated and 1023 K was found to be the optimal temperature. At lower temperatures, the oxynitride phase is not adequately produced, whereas higher temperatures produce more reduced niobium species (e. g., Nb³(+) and Nb⁴(+)), which can act as electron-hole recombination centers, resulting in a decrease in activity.

  4. Potential of SENTINEL-1A for Nation-Wide Routine Updates of Active Landslide Maps

    NASA Astrophysics Data System (ADS)

    Lazecky, M.; Canaslan Comut, F.; Nikolaeva, E.; Bakon, M.; Papco, J.; Ruiz-Armenteros, A. M.; Qin, Y.; de Sousa, J. J. M.; Ondrejka, P.

    2016-06-01

    Slope deformation is one of the typical geohazards that causes an extensive economic damage in mountainous regions. As such, they are usually intensively monitored by means of modern expertise commonly by national geological or emergency services. Resulting landslide susceptibility maps, or landslide inventories, offer an overview of areas affected by previously activated landslides as well as slopes known to be unstable currently. Current slope instabilities easily transform into a landslide after various triggering factors, such as an intensive rainfall or a melting snow cover. In these inventories, the majority of the existing landslide-affected slopes are marked as either stable or active, after a continuous investigative work of the experts in geology. In this paper we demonstrate the applicability of Sentinel-1A satellite SAR interferometry (InSAR) to assist by identifying slope movement activity and use the information to update national landslide inventories. This can be done reliably in cases of semi-arid regions or low vegetated slopes. We perform several analyses based on multitemporal InSAR techniques of Sentinel-1A data over selected areas prone to landslides.

  5. Non-conductive and miniature fiber-optic imaging system for real-time detection of neuronal activity in time-varying electromagnetic fields.

    PubMed

    Saito, Atsushi; Takahashi, Masayuki; Jimbo, Yasuhiko; Nakasono, Satoshi

    2017-01-15

    Establishing an appropriate threshold value for neuronal modulation by time-varying electromagnetic field (EMF) exposure is important for developing international guidelines to protect against the potential health effects, and to design a variety of medical devices. However, it is technically difficult to achieve real-time detection of neuronal activity under repetitive and long-term exposure to EMF. For this purpose, we developed a non-conductive, miniature, and flexible fiber-optic imaging system that does not affect the electromagnetic noise, induction heating, or vibration in a high-intensity and repetitive time-varying EMF exposure. Using the proposed system, we succeeded at real-time detection of spontaneous Ca(2+) oscillations in single neuronal and glial cells, as well as synchronized bursting activities of multiple neuronal networks at a micrometer-scale and millisecond-order spatiotemporal resolution during long-term EMF exposure (sinusoidal wave, 20kHz, 8.6mT, >30min). The results indicated that short-term (<5min) exposure-related neuronal modulation was not detectable; however, long-term (15-30min) exposure was observed to depress neuronal activities. In addition, the simultaneous and real-time recording of neuronal activity and the environmental temperature revealed that the neuronal modulation was accompanied by a 0.5-1°C rise in the temperature of the culture medium induced by the heat generation of exposure coils. These findings suggest that our real-time imaging system can be used for precise evaluation of the threshold values and clarification of the mechanisms of neuronal modulation induced by time-varying EMF exposure.

  6. Integrating Field-Centered, Project Based Activities with Academic Year Coursework: A Curriculum Wide Approach

    NASA Astrophysics Data System (ADS)

    Kelso, P. R.; Brown, L. M.

    2015-12-01

    Based upon constructivist principles and the recognition that many students are motivated by hands-on activities and field experiences, we designed a new undergraduate curriculum at Lake Superior State University. One of our major goals was to develop stand-alone field projects in most of the academic year courses. Examples of courses impacted include structural geology, geophysics, and geotectonics, Students learn geophysical concepts in the context of near surface field-based geophysical studies while students in structural geology learn about structural processes through outcrop study of fractures, folds and faults. In geotectonics students learn about collisional and rifting processes through on-site field studies of specific geologic provinces. Another goal was to integrate data and samples collected by students in our sophomore level introductory field course along with stand-alone field projects in our clastic systems and sequence stratigraphy courses. Our emphasis on active learning helps students develop a meaningful geoscience knowledge base and complex reasoning skills in authentic contexts. We simulate the activities of practicing geoscientists by engaging students in all aspects of a project, for example: field-oriented project planning and design; acquiring, analyzing, and interpreting data; incorporating supplemental material and background data; and preparing oral and written project reports. We find through anecdotal evidence including student comments and personal observation that the projects stimulate interest, provide motivation for learning new concepts, integrate skill and concept acquisition vertically through the curriculum, apply concepts from multiple geoscience subdisiplines, and develop soft skills such as team work, problem solving, critical thinking and communication skills. Through this projected-centered Lake Superior State University geology curriculum students practice our motto of "learn geology by doing geology."

  7. Removing static aberrations from the active optics system of a wide-field telescope.

    PubMed

    Schipani, Pietro; Noethe, Lothar; Arcidiacono, Carmelo; Argomedo, Javier; Dall'Ora, Massimo; D'Orsi, Sergio; Farinato, Jacopo; Magrin, Demetrio; Marty, Laurent; Ragazzoni, Roberto; Umbriaco, Gabriele

    2012-07-01

    The wavefront sensor in active and adaptive telescopes is usually not in the optical path toward the scientific detector. It may generate additional wavefront aberrations, which have to be separated from the errors due to the telescope optics. The aberrations that are not rotationally symmetric can be disentangled from the telescope aberrations by a series of measurements taken in the center of the field, with the wavefront sensor at different orientation angles with respect to the focal plane. This method has been applied at the VLT Survey Telescope on the ESO Paranal observatory.

  8. Contextual Correlates of Physical Activity among Older Adults: A Neighborhood Environment-Wide Association Study (NE-WAS).

    PubMed

    Mooney, Stephen J; Joshi, Spruha; Cerdá, Magdalena; Kennedy, Gary J; Beard, John R; Rundle, Andrew G

    2017-04-01

    Background: Few older adults achieve recommended physical activity levels. We conducted a "neighborhood environment-wide association study (NE-WAS)" of neighborhood influences on physical activity among older adults, analogous, in a genetic context, to a genome-wide association study.Methods: Physical Activity Scale for the Elderly (PASE) and sociodemographic data were collected via telephone survey of 3,497 residents of New York City aged 65 to 75 years. Using Geographic Information Systems, we created 337 variables describing each participant's residential neighborhood's built, social, and economic context. We used survey-weighted regression models adjusting for individual-level covariates to test for associations between each neighborhood variable and (i) total PASE score, (ii) gardening activity, (iii) walking, and (iv) housework (as a negative control). We also applied two "Big Data" analytic techniques, LASSO regression, and Random Forests, to algorithmically select neighborhood variables predictive of these four physical activity measures.Results: Of all 337 measures, proportion of residents living in extreme poverty was most strongly associated with total physical activity [-0.85; (95% confidence interval, -1.14 to -0.56) PASE units per 1% increase in proportion of residents living with household incomes less than half the federal poverty line]. Only neighborhood socioeconomic status and disorder measures were associated with total activity and gardening, whereas a broader range of measures was associated with walking. As expected, no neighborhood meaZsures were associated with housework after accounting for multiple comparisons.Conclusions: This systematic approach revealed patterns in the domains of neighborhood measures associated with physical activity.Impact: The NE-WAS approach appears to be a promising exploratory technique. Cancer Epidemiol Biomarkers Prev; 26(4); 495-504. ©2017 AACRSee all the articles in this CEBP Focus section, "Geospatial

  9. Bid, a Widely Expressed Proapoptotic Protein of the Bcl-2 Family, Displays Lipid Transfer Activity

    PubMed Central

    Esposti, Mauro Degli; Erler, Janine T.; Hickman, John A.; Dive, Caroline

    2001-01-01

    Bid is an abundant proapoptotic protein of the Bcl-2 family that is crucial for the induction of death receptor-mediated apoptosis in primary tissues such as liver. Bid action has been proposed to involve the relocation of its truncated form, tBid, to mitochondria to facilitate the release of apoptogenic cytochrome c. The mechanism of Bid relocation to mitochondria was unclear. We report here novel biochemical evidence indicating that Bid has lipid transfer activity between mitochondria and other intracellular membranes, thereby explaining its dynamic relocation to mitochondria. First, physiological concentrations of phospholipids such as phosphatidic acid and phosphatidylgycerol induced an accumulation of full-length Bid in mitochondria when incubated with light membranes enriched in endoplasmic reticulum. Secondly, native and recombinant Bid, as well as tBid, displayed lipid transfer activity under the same conditions and at the same nanomolar concentrations leading to mitochondrial relocation and release of cytochrome c. Thus, Bid is likely to be involved in the transport and recycling of mitochondrial phospholipids. We discuss how this new role of Bid may relate to its proapoptotic action. PMID:11585909

  10. Genome-wide distribution of Auts2 binding localizes with active neurodevelopmental genes.

    PubMed

    Oksenberg, N; Haliburton, G D E; Eckalbar, W L; Oren, I; Nishizaki, S; Murphy, K; Pollard, K S; Birnbaum, R Y; Ahituv, N

    2014-09-02

    The autism susceptibility candidate 2 gene (AUTS2) has been associated with multiple neurological diseases including autism spectrum disorders (ASDs). Previous studies showed that AUTS2 has an important neurodevelopmental function and is a suspected master regulator of genes implicated in ASD-related pathways. However, the regulatory role and targets of Auts2 are not well known. Here, by using ChIP-seq (chromatin immunoprecipitation followed by deep sequencing) and RNA-seq on mouse embryonic day 16.5 forebrains, we elucidated the gene regulatory networks of Auts2. We find that the majority of promoters bound by Auts2 belong to genes highly expressed in the developing forebrain, suggesting that Auts2 is involved in transcriptional activation. Auts2 non-promoter-bound regions significantly overlap developing brain-associated enhancer marks and are located near genes involved in neurodevelopment. Auts2-marked sequences are enriched for binding site motifs of neurodevelopmental transcription factors, including Pitx3 and TCF3. In addition, we characterized two functional brain enhancers marked by Auts2 near NRXN1 and ATP2B2, both ASD-implicated genes. Our results implicate Auts2 as an active regulator of important neurodevelopmental genes and pathways and identify novel genomic regions that could be associated with ASD and other neurodevelopmental diseases.

  11. Genome-wide identification of neuronal activity-regulated genes in Drosophila

    PubMed Central

    Chen, Xiao; Rahman, Reazur; Guo, Fang; Rosbash, Michael

    2016-01-01

    Activity-regulated genes (ARGs) are important for neuronal functions like long-term memory and are well-characterized in mammals but poorly studied in other model organisms like Drosophila. Here we stimulated fly neurons with different paradigms and identified ARGs using high-throughput sequencing from brains as well as from sorted neurons: they included a narrow set of circadian neurons as well as dopaminergic neurons. Surprisingly, many ARGs are specific to the stimulation paradigm and very specific to neuron type. In addition and unlike mammalian immediate early genes (IEGs), fly ARGs do not have short gene lengths and are less enriched for transcription factor function. Chromatin assays using ATAC-sequencing show that the transcription start sites (TSS) of ARGs do not change with neural firing but are already accessible prior to stimulation. Lastly based on binding site enrichment in ARGs, we identified transcription factor mediators of firing and created neuronal activity reporters. DOI: http://dx.doi.org/10.7554/eLife.19942.001 PMID:27936378

  12. Chromolaena odorata: A neglected weed with a wide spectrum of pharmacological activities (Review).

    PubMed

    Vijayaraghavan, Kavitha; Rajkumar, Johanna; Bukhari, Syed Nasir Abbas; Al-Sayed, Badr; Seyed, Mohammed Ali

    2017-03-01

    The study of wound‑healing plants has acquired an interdisciplinary nature with a systematic investigational approach. Several biochemicals are involved in the healing process of the body, including antioxidants and cytokines. Although several pharmaceutical preparations and formulations are available for wound care and management, it remains necessary to search for efficacious treatments, as certain current formulations cause adverse effects or lack efficacy. Phytochemicals or biomarkers from numerous plants suggest they have positive effects on different stages of the wound healing process via various mechanisms. Several herbal medicines have displayed marked activity in the management of wounds and various natural compounds have verified in vivo wound healing potential, and can, therefore, be considered as potential drugs of natural origin. Chromolaena odorata (L.) R.M. King and H. Robinson is considered a tropical weed. However, it exhibits anti‑inflammatory, antipyretic, analgesic, antimicrobial, cytotoxic and numerous other relevant medicinal properties on an appreciable scale, and is known in some parts of the world as a traditional medicine used to treat various ailments. To understand its specific role as nature's gift for healing wounds and its contribution to affordable healthcare, this plant must be scientifically assessed based on the available literature. This review aims to summarize the role of C. odorata and its biomarkers in the wound healing activities of biological systems, which are crucial to its potential future drug design, development and application for the treatment of wounds.

  13. Coexistence and local μ-stability of multiple equilibrium points for memristive neural networks with nonmonotonic piecewise linear activation functions and unbounded time-varying delays.

    PubMed

    Nie, Xiaobing; Zheng, Wei Xing; Cao, Jinde

    2016-12-01

    In this paper, the coexistence and dynamical behaviors of multiple equilibrium points are discussed for a class of memristive neural networks (MNNs) with unbounded time-varying delays and nonmonotonic piecewise linear activation functions. By means of the fixed point theorem, nonsmooth analysis theory and rigorous mathematical analysis, it is proven that under some conditions, such n-neuron MNNs can have 5(n) equilibrium points located in ℜ(n), and 3(n) of them are locally μ-stable. As a direct application, some criteria are also obtained on the multiple exponential stability, multiple power stability, multiple log-stability and multiple log-log-stability. All these results reveal that the addressed neural networks with activation functions introduced in this paper can generate greater storage capacity than the ones with Mexican-hat-type activation function. Numerical simulations are presented to substantiate the theoretical results.

  14. A Wide-Band, Active Antenna System for Long Wavelength Radio Astronomy

    NASA Astrophysics Data System (ADS)

    Hicks, Brian C.; Paravastu-Dalal, Nagini; Stewart, Kenneth P.; Erickson, William C.; Ray, Paul S.; Kassim, Namir E.; Burns, Steve; Clarke, Tracy; Schmitt, Henrique; Craig, Joe; Hartman, Jake; Weiler, Kurt W.

    2012-10-01

    We describe an “active” antenna system for HF/VHF (long wavelength) radio astronomy that has been successfully deployed 256-fold as the first station (LWA1) of the planned Long Wavelength Array. The antenna system, consisting of crossed dipoles, an active balun/preamp, a support structure, and a ground screen has been shown to successfully operate over at least the band from 20 MHz (15 m wavelength) to 80 MHz (3.75 m wavelength) with a noise figure that is at least 6 dB better than the Galactic background emission-noise temperature over that band. Thus, we met the goal to design and construct a compact, inexpensive, rugged, and easily assembled antenna system that can be deployed many-fold to form numerous large individual “stations” for the purpose of building a large, long wavelength synthesis array telescope for radio astronomical and ionospheric observations.

  15. Adult activity and temperature preference drives region-wide damselfly (Zygoptera) distributions under a warming climate

    PubMed Central

    Corser, Jeffrey D.; White, Erin L.; Schlesinger, Matthew D.

    2015-01-01

    We analysed a recently completed statewide odonate Atlas using multivariate linear models. Within a phylogenetically explicit framework, we developed a suite of data-derived traits to assess the mechanistic distributional drivers of 59 species of damselflies in New York State (NYS). We found that length of the flight season (adult breeding activity period) mediated by thermal preference drives regional distributions at broad (105 km2) scales. Species that had longer adult flight periods, in conjunction with longer growing seasons, had significantly wider distributions. These intrinsic traits shape species' responses to changing climates and the mechanisms behind such range shifts are fitness-based metapopulation processes that adjust phenology to the prevailing habitat and climate regime through a photoperiod filter. PMID:25878048

  16. B7x: A widely expressed B7 family member that inhibits T cell activation

    PubMed Central

    Zang, Xingxing; Loke, P'ng; Kim, Jayon; Murphy, Kenneth; Waitz, Rebecca; Allison, James P.

    2003-01-01

    B7 family proteins provide costimulatory signals that regulate T cell responses. Here we report the third set of B7 family-related T cell inhibitory molecules with the identification of a homolog of the B7 family, B7x. It is expressed in immune cells, nonlymphoid tissues, and some tumor cell lines. B7x inhibits cell-cycle progression, proliferation, and cytokine production of both CD4+ and CD8+ T cells. B7x binds a receptor that is expressed on activated, but not resting T cells that is distinct from known CD28 family members. Its receptor may be a recently identified inhibitory molecule, B and T lymphocyte attenuator. These studies identify a costimulatory pathway that may have a unique function in downregulation of tissue-specific autoimmunity and antitumor responses. PMID:12920180

  17. Brain-wide mapping of neural activity controlling zebrafish exploratory locomotion

    PubMed Central

    Dunn, Timothy W; Mu, Yu; Narayan, Sujatha; Randlett, Owen; Naumann, Eva A; Yang, Chao-Tsung; Schier, Alexander F

    2016-01-01

    In the absence of salient sensory cues to guide behavior, animals must still execute sequences of motor actions in order to forage and explore. How such successive motor actions are coordinated to form global locomotion trajectories is unknown. We mapped the structure of larval zebrafish swim trajectories in homogeneous environments and found that trajectories were characterized by alternating sequences of repeated turns to the left and to the right. Using whole-brain light-sheet imaging, we identified activity relating to the behavior in specific neural populations that we termed the anterior rhombencephalic turning region (ARTR). ARTR perturbations biased swim direction and reduced the dependence of turn direction on turn history, indicating that the ARTR is part of a network generating the temporal correlations in turn direction. We also find suggestive evidence for ARTR mutual inhibition and ARTR projections to premotor neurons. Finally, simulations suggest the observed turn sequences may underlie efficient exploration of local environments. DOI: http://dx.doi.org/10.7554/eLife.12741.001 PMID:27003593

  18. The histone modification pattern of active genes revealed through genome-wide chromatin analysis of a higher eukaryote

    PubMed Central

    Schübeler, Dirk; MacAlpine, David M.; Scalzo, David; Wirbelauer, Christiane; Kooperberg, Charles; van Leeuwen, Fred; Gottschling, Daniel E.; O'Neill, Laura P.; Turner, Bryan M.; Delrow, Jeffrey; Bell, Stephen P.; Groudine, Mark

    2004-01-01

    The covalent modification of nucleosomal histones has emerged as a major determinant of chromatin structure and gene activity. To understand the interplay between various histone modifications, including acetylation and methylation, we performed a genome-wide chromatin structure analysis in a higher eukaryote. We found a binary pattern of histone modifications among euchromatic genes, with active genes being hyperacetylated for H3 and H4 and hypermethylated at Lys 4 and Lys 79 of H3, and inactive genes being hypomethylated and deacetylated at the same residues. Furthermore, the degree of modification correlates with the level of transcription, and modifications are largely restricted to transcribed regions, suggesting that their regulation is tightly linked to polymerase activity. PMID:15175259

  19. miRNA gene counts in chromosomes vary widely in a species and biogenesis of miRNA largely depends on transcription or post-transcriptional processing of coding genes

    PubMed Central

    Ghorai, Atanu; Ghosh, Utpal

    2014-01-01

    MicroRNAs target specific mRNA(s) to silence its expression and thereby regulate various cellular processes. We have investigated miRNA gene counts in chromosomes for 20 different species and observed wide variation. Certain chromosomes have extremely high number of miRNA gene compared with others in all the species. For example, high number of miRNA gene in X chromosome and the least or absence of miRNA gene in Y chromosome was observed in all species. To search the criteria governing such variation of miRNA gene counts in chromosomes, we have selected three parameters- length, number of non-coding and coding genes in a chromosome. We have calculated Pearson's correlation coefficient of miRNA gene counts with length, number of non-coding and coding genes in a chromosome for all 20 species. Major number of species showed that number of miRNA gene was not correlated with chromosome length. Eighty five percent of species under study showed strong positive correlation coefficient (r ≥ 0.5) between the numbers of miRNA gene vs. non-coding gene in chromosomes as expected because miRNA is a sub-set of non-coding genes. 55% species under study showed strong positive correlation coefficient (r ≥ 0.5) between numbers of miRNA gene vs. coding gene. We hypothesize biogenesis of miRNA largely depends on coding genes, an evolutionary conserved process. Chromosomes having higher number of miRNA genes will be most likely playing regulatory roles in several cellular processes including different disorders. In humans, cancer and cardiovascular disease associated miRNAs are mostly intergenic and located in Chromosome 19, X, 14, and 1. PMID:24808907

  20. Batch and column adsorption of herbicide fluroxypyr on different types of activated carbons from water with varied degrees of hardness and alkalinity.

    PubMed

    Pastrana-Martínez, L M; López-Ramón, M V; Fontecha-Cámara, M A; Moreno-Castilla, C

    2010-02-01

    There has been little research into the effects of the water hardness and alkalinity of surface waters on the adsorption of herbicides on activated carbons. The aim of this study was to determine the influence of these water characteristics on fluroxypyr adsorption on different activated carbons. At low fluroxypyr surface concentrations, the amount adsorbed from distilled water was related to the surface hydrophobicity. Surface area of carbons covered by fluroxypyr molecules ranged from 60 to 65%. Variations in fluroxypyr solubility with water hardness and alkalinity showed a salting-in effect. Calcium, magnesium and bicarbonate ions were adsorbed to a varied extent on the activated carbons. The presence of fluroxypyr in solution decreased their adsorption due to a competition effect. K(F) from the Freundlich equation linearly increased with water hardness due to salt-screened electrostatic repulsions between charged fluroxypyr molecules. The amount adsorbed from distilled water was largest at high fluroxypyr solution concentrations, because there was no competition between inorganic ions and fluroxypyr molecules. The column breakthrough volume and the amount adsorbed at breakthrough were smaller in tap versus distilled water. Carbon consumption was lower with activated carbon cloth than with the use of granular activated carbon.

  1. A genome-wide function of THSC/TREX-2 at active genes prevents transcription–replication collisions

    PubMed Central

    Santos-Pereira, José M.; García-Rubio, María L.; González-Aguilera, Cristina; Luna, Rosa; Aguilera, Andrés

    2014-01-01

    The THSC/TREX-2 complex of Saccharomyces cerevisiae mediates the anchoring of transcribed genes to the nuclear pore, linking transcription elongation with mRNA export and genome stability, as shown for specific reporters. However, it is still unknown whether the function of TREX-2 is global and the reason for its relevant role in genome integrity. Here, by studying two TREX-2 representative subunits, Thp1 and Sac3, we show that TREX-2 has a genome-wide role in gene expression. Both proteins show similar distributions along the genome, with a gradient disposition at active genes that increases towards the 3′ end. Thp1 and Sac3 have a relevant impact on the expression of long, G+C-rich and highly transcribed genes. Interestingly, replication impairment detected by the genome-wide accumulation of the replicative Rrm3 helicase is increased preferentially at highly expressed genes in the thp1Δ and sac3Δ mutants analyzed. Therefore, our work provides evidence of a function of TREX-2 at the genome-wide level and suggests a role for TREX-2 in preventing transcription–replication conflicts, as a source of genome instability derived from a defective messenger ribonucleoprotein particle (mRNP) biogenesis. PMID:25294824

  2. Viminaria juncea does not vary its shoot phosphorus concentration and only marginally decreases its mycorrhizal colonization and cluster-root dry weight under a wide range of phosphorus supplies

    PubMed Central

    de Campos, Mariana C. R.; Pearse, Stuart J.; Oliveira, Rafael S.; Lambers, Hans

    2013-01-01

    Background and Aims The Australian legume species Viminaria juncea forms both cluster roots and mycorrhizal associations. The aim of this study was to identify if these root specializations are expressed at differential supplies of phosphorus (P) and at different shoot P concentrations [P]. Methods Seedlings were planted in sand and provided with a mycorrhizal inoculum and basal nutrients plus one of 21 P treatments, ranging from 0 to 50 mg P kg−1 dry soil. Plants were harvested after 12 weeks, and roots, shoots and cluster roots were measured for length and fresh and dry weight. The number of cluster roots, the percentage of mycorrhizal colonization, and shoot [P] were determined. Key Results Shoot biomass accumulation increased with increasing P supply until a shoot dry weight of 3 g was reached at a P supply of approx. 27·5 mg P kg−1 dry soil. Neither cluster-root formation nor mycorrhizal colonization was fully suppressed at the highest P supply. Most intriguingly, shoot [P] did not differ across treatments, with an average of 1·4 mg P kg−1 shoot dry weight. Conclusions The almost constant shoot [P] in V. juncea over the very wide range of P supplies is, to our knowledge, unprecedented. To maintain these stable values, this species down-regulates its growth rate when no P is supplied; conversely, it down-regulates its P-uptake capacity very tightly at the highest P supplies, when its maximum growth rate has been reached. It is proposed that the persistence of cluster roots and mycorrhizal colonization up to the highest P treatments is a consequence of its tightly controlled shoot [P]. This unusual P physiology of V. juncea is surmised to be related to the habitat of this N2-fixing species. Water and nutrients are available at a low but steady supply for most of the year, negating the need for storage of P which would be metabolically costly and be at the expense of metabolic energy and P available for symbiotic N2 fixation. PMID:23456689

  3. Varying DNA base-pair size in subangstrom increments: evidence for a loose, not large, active site in low-fidelity Dpo4 polymerase.

    PubMed

    Mizukami, Shin; Kim, Tae Woo; Helquist, Sandra A; Kool, Eric T

    2006-03-07

    We describe the first systematic test of steric effects in the active site of a Y-family DNA polymerase, Dpo4. It has been hypothesized that low-fidelity repair polymerases in this family more readily accept damaged or mismatched base pairs because of a sterically more open active site, which might place lower geometric constraints on the incipient pair. We have tested the origin of low fidelity by use of five nonpolar thymidine analogues that vary in size by a total of 1.0 A over the series. The efficiency and fidelity of base-pair synthesis was measured by steady-state kinetics for single-nucleotide insertions. Analogues were examined both as incoming deoxynucleoside triphosphate (dNTP) derivatives and as template bases. The results showed that Dpo4 preferred to pair the thymidine shape mimics with adenine and, surprisingly, the preferred size was at the center of the range, the same optimum size as recently found for the high-fidelity Klenow fragment (Kf) of Escherichia coli DNA Pol I. However, the size preference with Dpo4 was quite small, varying by a factor of only 30-35 from most to least efficient thymidine analogue. This is in marked contrast to Kf, which showed a rigid size preference, varying by 1100-fold from best to worst. The fidelity for the non-hydrogen-bonding analogues in pairing with A over T, C, or G was much lower in Dpo4 than in the previous high-fidelity enzyme. The data establish that, unlike Kf, Dpo4 has very low steric selectivity and that steric effects alone cannot explain the fidelity (albeit low) that Dpo4 has for a correct base pair; the findings suggest that hydrogen bonds may be important in determining the fidelity of this enzyme. The results suggest that the low steric selectivity of this enzyme is the result of a conformationally flexible or loose active site that adapts with small energetic cost to different base-pair sizes (as measured by the glycosidic C1'-C1' distance), rather than a spatially large active site.

  4. Wide field-of-view, multi-region two-photon imaging of neuronal activity in the mammalian brain

    PubMed Central

    Stirman, Jeffrey N.; Smith, Ikuko T.; Kudenov, Michael W.; Smith, Spencer L.

    2016-01-01

    Two-photon calcium imaging provides an optical readout of neuronal activity in populations of neurons with subcellular resolution. However, conventional two-photon imaging systems are limited in their field of view to ~1 mm2, precluding the visualization of multiple cortical areas simultaneously. Here, we demonstrate a two-photon microscope with an expanded field of view (>9.5 mm2) for rapidly reconfigurable simultaneous scanning of widely separated populations of neurons. We custom designed and assembled an optimized scan engine, objective, and two independently positionable, temporally multiplexed excitation pathways. We used this new microscope to measure activity correlations between two cortical visual areas in mice during visual processing. PMID:27347754

  5. The Genome-Wide Influence on Human BMI Depends on Physical Activity, Life Course, and Historical Period.

    PubMed

    Guo, Guang; Liu, Hexuan; Wang, Ling; Shen, Haipeng; Hu, Wen

    2015-10-01

    In this analysis, guided by an evolutionary framework, we investigate how the human genome as a whole interacts with historical period, age, and physical activity to influence body mass index (BMI). The genomic influence is estimated by (1) heritability or the proportion of variance in BMI explained by genome-wide genotype data, and (2) the random effects or the best linear unbiased predictors (BLUPs) of genome-wide association studies (GWAS) data on BMI. Data were used from the Framingham Heart Study (FHS) in the United States. The study was initiated in 1948, and the obesity data were collected repeatedly over the subsequent decades. The analyses draw analysis samples from a pool of >8,000 individuals in the FHS. The hypothesis testing based on Pitman test, permutation Pitman test, F test, and permutation F test produces three sets of significant findings. First, the genomic influence on BMI is substantially larger after the mid-1980s than in the few decades before the mid-1980s within each age group of 21-40, 41-50, 51-60, and >60. Second, the genomic influence on BMI weakens as one ages across the life course, or the genomic influence on BMI tends to be more important during reproductive ages than after reproductive ages within each of the two historical periods. Third, within the age group of 21-50 and not in the age group of >50, the genomic influence on BMI among physically active individuals is substantially smaller than the influence on those who are not physically active. In summary, this study provides evidence that the influence of human genome as a whole on obesity depends on historical period, age, and level of physical activity.

  6. Binding of nickel and copper to fish gills predicts toxicity when water hardness varies, but free-ion activity does not

    SciTech Connect

    Meyer, J.S.; Bobbitt, J.P.; Debrey, L.D.; Boese, C.J.; Bergman, H.L.; Santore, R.C.; Paquin, P.R.; Ditoro, D.M.; Allen, H.E.

    1999-03-15

    Based on a biotic-ligand model (BLM), the authors hypothesized that the concentration of a transition metal bound to fish gills ([M{sub gill}]) will be a constant predictor of mortality, whereas a free-ion activity model is generally interpreted to imply that the chemical activity of the aquo (free) ion of the metal will be a constant predictor of mortality. In laboratory tests, measured [Ni{sub gill}] and calculated [Cu{sub gill}] were constant predictors of acute toxicity of Ni and Cu to fathead minnows (Pimephales promelas) when water hardness varied up to 10-fold, whereas total aqueous concentrations and free-ion activities of Ni and Cu were not. Thus, the BLM, which simultaneously accounts for (a) metal speciation in the exposure water and (b) competitive binding of transition-metal ions and other cations to biotic ligands predicts acute toxicity better than does free-ion activity of Ni or Cu. Adopting a biotic-ligand modeling approach could help establish a more defensible, mechanistic basis for regulating aqueous discharges of metals.

  7. Population Pharmacokinetic Model for Docetaxel in Patients with Varying Degrees of Liver Function: Incorporating Cytochrome P450 3A Activity Measurements

    PubMed Central

    Hooker, AC; ten Tije, AJ; Carducci, MA; Weber, J; Garrett-Mayer, E; Gelderblom, H; McGuire, WP; Verweij, J; Karlsson, MO; Baker, SD

    2011-01-01

    The relationship between cytochrome P4503A4 (CYP3A4) activity and docetaxel clearance in patients with varying degrees of liver function (LF) was evaluated. Docetaxel 40, 50, or 75 mg/m2 was administered to 85 patients with advanced cancer; 23 of 77 evaluable patients had abnormalities in liver function tests. Baseline CYP3A activity was assessed using the erythromycin breath test (ERMBT). Pharmacokinetic studies and toxicity assessments were performed during cycle 1 of therapy and population modeling was performed using NONMEM. Docetaxel unbound clearance was lower (317 vs. 470 L/h) and more variable in patients with liver function abnormalities compared to patients with normal LF. Covariates evaluated accounted for 83% of variability on clearance in patients with liver dysfunction, with CYP3A4 activity accounting for 47% of variation; covariates accounted for only 23% of variability in patients with normal LF. The clinical utility of the ERMBT may be in identifying safe docetaxel doses for patients with LF abnormalities. PMID:18183036

  8. Temporal relationships between ceramide production, caspase activation and mitochondrial dysfunction in cell lines with varying sensitivity to anti-Fas-induced apoptosis.

    PubMed Central

    Rodriguez-Lafrasse, C; Alphonse, G; Broquet, P; Aloy, M T; Louisot, P; Rousson, R

    2001-01-01

    To clarify the chronology of events leading to anti-Fas-induced apoptosis, and the mechanisms of resistance to this death effector, we compared the response kinetics of three tumour cell lines that display varying sensitivity to anti-Fas (based on levels of apoptosis), in terms of ceramide release, mitochondrial function and the caspase-activation pathway. In the highly sensitive Jurkat cell line, early caspase-8 activation, observed from 2 h after treatment, was chronologically associated with an acute depletion of glutathione and the cleavage of caspase-3 and poly-ADP ribosyl polymerase (PARP), followed by a progressive fall in the mitochondrial transmembrane potential (Delta(psi)m), between 4 and 48 h after treatment. Ceramide levels began to increase 2 h after the addition of anti-Fas (with no increase during the first hour), and increased continuously to 640% of control cells at 48 h. In the moderately sensitive SCC61 adherent cells, comparable results were observed, though with lower levels of ceramide and a delay in the response kinetics, with apoptotic cells becoming flotant. Finally, despite early cleavage of caspase-8 at 2 h, and a sustained level of activation until 48 h, no apoptotic response was observed in anti-Fas-resistant SQ20B cells. This was confirmed by a lack of ceramide generation and mitochondrial changes, and by the absence of any detectable cleavage of caspase-3 or PARP. Inhibition of caspase processing, and amplification of endogenous ceramide signalling by pharmacological agents, allowed us to establish the order of cellular events, locating ceramide release after caspase-8 activation and before caspase-3 activation, and demonstrating a direct involvement for ceramide release in mitochondrial dysfunction. Furthermore, these experiments provide strong arguments for the role of endogenous ceramide as a key executor of apoptosis, rather than as a consequence of membrane alterations. PMID:11439090

  9. Adsorption capacities of activated carbons for geosmin and 2-methylisoborneol vary with activated carbon particle size: Effects of adsorbent and adsorbate characteristics.

    PubMed

    Matsui, Yoshihiko; Nakao, Soichi; Sakamoto, Asuka; Taniguchi, Takuma; Pan, Long; Matsushita, Taku; Shirasaki, Nobutaka

    2015-11-15

    The adsorption capacities of nine activated carbons for geosmin and 2-methylisoborneol (MIB) were evaluated. For some carbons, adsorption capacity substantially increased when carbon particle diameter was decreased from a few tens of micrometers to a few micrometers, whereas for other carbons, the increase of adsorption capacity was small for MIB and moderate for geosmin. An increase of adsorption capacity was observed for other hydrophobic adsorbates besides geosmin and MIB, but not for hydrophilic adsorbates. The parameter values of a shell adsorption model describing the increase of adsorption capacity were negatively correlated with the oxygen content of the carbon among other characteristics. Low oxygen content indicated low hydrophilicity. The increase of adsorption capacity was related to the hydrophobic properties of both adsorbates and activated carbons. For adsorptive removal of hydrophobic micropollutants such as geosmin, it is therefore recommended that less-hydrophilic activated carbons, such as coconut-shell-based carbons, be microground to a particle diameter of a few micrometers to enhance their equilibrium adsorption capacity. In contrast, adsorption by hydrophilic carbons or adsorption of hydrophilic adsorbates occur in the inner pores, and therefore adsorption capacity is unchanged by particle size reduction.

  10. Peroxidase-like activity of gold nanoparticles stabilized by hyperbranched polyglycidol derivatives over a wide pH range

    NASA Astrophysics Data System (ADS)

    Drozd, Marcin; Pietrzak, Mariusz; Parzuchowski, Paweł; Mazurkiewicz-Pawlicka, Marta; Malinowska, Elżbieta

    2015-12-01

    The aim of this work was to carry out comparative studies on the peroxidase-like activity of gold nanoparticles (AuNPs) stabilized with low molecular weight hyperbranched polyglycidol (HBPG-OH) and its derivative modified with maleic acid residues (HBPG-COOH). The influence of the stabilizer to gold precursor ratio on the size and morphology of nanoparticles obtained was checked, and prepared nanoparticles were characterized by means of transmission electron microscopy and UV-Vis spectroscopy. The results indicated the divergent effect of increasing the concentration of stabilizers (HBPG-OH or HBPG-COOH) on the size of the nanostructures obtained. The gold nanoparticles obtained were characterized as having intrinsic peroxidase-like activity and the mechanism of catalysis in acidic and alkaline mediums was consistent with the standard Michaelis-Menten kinetics, revealing a strong affinity of AuNPs with 2, 2‧-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 3, 3‧, 5, 5‧-tetramethylbenzidine (TMB), and significantly lower affinity towards phenol. By comparing the kinetic parameters, a negligible effect of polymeric ligand charge on activity against various types of substrates (anionic or cationic) was indicated. The superiority of steric stabilization via the application of tested low-weight hyperbranched polymers over typical stabilizers in preventing salt-induced aggregation and maintaining high catalytic activity in time was proved. The applied hyperbranched stabilizers provide a good tool for manufacturing gold-based nanozymes, which are highly stable and active over a wide pH range.

  11. Thuringiensin: a thermostable secondary metabolite from Bacillus thuringiensis with insecticidal activity against a wide range of insects.

    PubMed

    Liu, Xiaoyan; Ruan, Lifang; Peng, Donghai; Li, Lin; Sun, Ming; Yu, Ziniu

    2014-07-25

    Thuringiensin (Thu), also known as β-exotoxin, is a thermostable secondary metabolite secreted by Bacillus thuringiensis. It has insecticidal activity against a wide range of insects, including species belonging to the orders Diptera, Coleoptera, Lepidoptera, Hymenoptera, Orthoptera, and Isoptera, and several nematode species. The chemical formula of Thu is C22H32O19N5P, and it is composed of adenosine, glucose, phosphoric acid, and gluconic diacid. In contrast to the more frequently studied insecticidal crystal protein, Thu is not a protein but a small molecule oligosaccharide. In this review, a detailed and updated description of the characteristics, structure, insecticidal mechanism, separation and purification technology, and genetic determinants of Thu is provided.

  12. Thuringiensin: A Thermostable Secondary Metabolite from Bacillus thuringiensis with Insecticidal Activity against a Wide Range of Insects

    PubMed Central

    Liu, Xiaoyan; Ruan, Lifang; Peng, Donghai; Li, Lin; Sun, Ming; Yu, Ziniu

    2014-01-01

    Thuringiensin (Thu), also known as β-exotoxin, is a thermostable secondary metabolite secreted by Bacillus thuringiensis. It has insecticidal activity against a wide range of insects, including species belonging to the orders Diptera, Coleoptera, Lepidoptera, Hymenoptera, Orthoptera, and Isoptera, and several nematode species. The chemical formula of Thu is C22H32O19N5P, and it is composed of adenosine, glucose, phosphoric acid, and gluconic diacid. In contrast to the more frequently studied insecticidal crystal protein, Thu is not a protein but a small molecule oligosaccharide. In this review, a detailed and updated description of the characteristics, structure, insecticidal mechanism, separation and purification technology, and genetic determinants of Thu is provided. PMID:25068925

  13. Transcriptional activities of methanogens and methanotrophs vary with methane emission flux in rice soils under chronic nutrient constraints of phosphorus and potassium

    NASA Astrophysics Data System (ADS)

    Sheng, Rong; Chen, Anlei; Zhang, Miaomiao; Whiteley, Andrew S.; Kumaresan, Deepak; Wei, Wenxue

    2016-12-01

    Nutrient status in soil is crucial for the growth and development of plants which indirectly or directly affect the ecophysiological functions of resident soil microorganisms. Soil methanogens and methanotrophs can be affected by soil nutrient availabilities and plant growth, which in turn modulate methane (CH4) emissions. Here, we assessed whether deficits in soil-available phosphorus (P) and potassium (K) modulated the activities of methanogens and methanotrophs in a long-term (20 year) experimental system involving limitation in either one or both nutrients. Results showed that a large amount of CH4 was emitted from paddy soil at rice tillering stage (flooding) while CH4 flux was minimum at ripening stage (drying). Compared to soils amended with NPK fertiliser treatment, the soils without P input significantly reduced methane flux rates, whereas those without K input did not. Under P limitation, methanotroph transcript copy number significantly increased in tandem with a decrease in methanogen transcript abundance, suggesting that P-deficiency-induced changes in soil physio-chemical properties, in tandem with rice plant growth, might constrain the activity of methanogens, whereas the methanotrophs might be adaptive to this soil environment. In contrast, lower transcript abundance of both methanogen and methanotrophs were observed in K-deficient soils. Assessments of community structures based upon transcripts indicated that soils deficient in P induced greater shifts in the active methanotrophic community than K-deficient soils, while similar community structures of active methanogens were observed in both treatments. These results suggested that the population dynamics of methanogens and methanotrophs could vary along with the changes in plant growth states and soil properties induced by nutrient deficiency.

  14. A Novel Time-Varying Spectral Filtering Algorithm for Reconstruction of Motion Artifact Corrupted Heart Rate Signals During Intense Physical Activities Using a Wearable Photoplethysmogram Sensor

    PubMed Central

    Salehizadeh, Seyed M. A.; Dao, Duy; Bolkhovsky, Jeffrey; Cho, Chae; Mendelson, Yitzhak; Chon, Ki H.

    2015-01-01

    Accurate estimation of heart rates from photoplethysmogram (PPG) signals during intense physical activity is a very challenging problem. This is because strenuous and high intensity exercise can result in severe motion artifacts in PPG signals, making accurate heart rate (HR) estimation difficult. In this study we investigated a novel technique to accurately reconstruct motion-corrupted PPG signals and HR based on time-varying spectral analysis. The algorithm is called Spectral filter algorithm for Motion Artifacts and heart rate reconstruction (SpaMA). The idea is to calculate the power spectral density of both PPG and accelerometer signals for each time shift of a windowed data segment. By comparing time-varying spectra of PPG and accelerometer data, those frequency peaks resulting from motion artifacts can be distinguished from the PPG spectrum. The SpaMA approach was applied to three different datasets and four types of activities: (1) training datasets from the 2015 IEEE Signal Process. Cup Database recorded from 12 subjects while performing treadmill exercise from 1 km/h to 15 km/h; (2) test datasets from the 2015 IEEE Signal Process. Cup Database recorded from 11 subjects while performing forearm and upper arm exercise. (3) Chon Lab dataset including 10 min recordings from 10 subjects during treadmill exercise. The ECG signals from all three datasets provided the reference HRs which were used to determine the accuracy of our SpaMA algorithm. The performance of the SpaMA approach was calculated by computing the mean absolute error between the estimated HR from the PPG and the reference HR from the ECG. The average estimation errors using our method on the first, second and third datasets are 0.89, 1.93 and 1.38 beats/min respectively, while the overall error on all 33 subjects is 1.86 beats/min and the performance on only treadmill experiment datasets (22 subjects) is 1.11 beats/min. Moreover, it was found that dynamics of heart rate variability can be

  15. A Novel Time-Varying Spectral Filtering Algorithm for Reconstruction of Motion Artifact Corrupted Heart Rate Signals During Intense Physical Activities Using a Wearable Photoplethysmogram Sensor.

    PubMed

    Salehizadeh, Seyed M A; Dao, Duy; Bolkhovsky, Jeffrey; Cho, Chae; Mendelson, Yitzhak; Chon, Ki H

    2015-12-23

    Accurate estimation of heart rates from photoplethysmogram (PPG) signals during intense physical activity is a very challenging problem. This is because strenuous and high intensity exercise can result in severe motion artifacts in PPG signals, making accurate heart rate (HR) estimation difficult. In this study we investigated a novel technique to accurately reconstruct motion-corrupted PPG signals and HR based on time-varying spectral analysis. The algorithm is called Spectral filter algorithm for Motion Artifacts and heart rate reconstruction (SpaMA). The idea is to calculate the power spectral density of both PPG and accelerometer signals for each time shift of a windowed data segment. By comparing time-varying spectra of PPG and accelerometer data, those frequency peaks resulting from motion artifacts can be distinguished from the PPG spectrum. The SpaMA approach was applied to three different datasets and four types of activities: (1) training datasets from the 2015 IEEE Signal Process. Cup Database recorded from 12 subjects while performing treadmill exercise from 1 km/h to 15 km/h; (2) test datasets from the 2015 IEEE Signal Process. Cup Database recorded from 11 subjects while performing forearm and upper arm exercise. (3) Chon Lab dataset including 10 min recordings from 10 subjects during treadmill exercise. The ECG signals from all three datasets provided the reference HRs which were used to determine the accuracy of our SpaMA algorithm. The performance of the SpaMA approach was calculated by computing the mean absolute error between the estimated HR from the PPG and the reference HR from the ECG. The average estimation errors using our method on the first, second and third datasets are 0.89, 1.93 and 1.38 beats/min respectively, while the overall error on all 33 subjects is 1.86 beats/min and the performance on only treadmill experiment datasets (22 subjects) is 1.11 beats/min. Moreover, it was found that dynamics of heart rate variability can be

  16. Activation of muscarinic receptors by ACh release in hippocampal CA1 depolarizes VIP but has varying effects on parvalbumin-expressing basket cells

    PubMed Central

    Bell, L Andrew; Bell, Karen A; McQuiston, A Rory

    2015-01-01

    We investigated the effect of acetylcholine release on mouse hippocampal CA1 perisomatically projecting interneurons. Acetylcholine was optogenetically released in hippocampal slices by expressing the excitatory optogenetic protein oChIEF-tdTomato in medial septum/diagonal band of Broca cholinergic neurons using Cre recombinase-dependent adeno-associated virally mediated transfection. The effect of optogenetically released acetylcholine was assessed on interneurons expressing Cre recombinase in vasoactive intestinal peptide (VIP) or parvalbumin (PV) interneurons using whole cell patch clamp methods. Acetylcholine released onto VIP interneurons that innervate pyramidal neuron perisomatic regions (basket cells, BCs) were depolarized by muscarinic receptors. Although PV BCs were also excited by muscarinic receptor activation, they more frequently responded with hyperpolarizing or biphasic responses. Muscarinic receptor activation resulting from ACh release increased the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) in downstream hippocampal CA1 pyramidal neurons with peak instantaneous frequencies occurring in both the gamma and theta bandwidths. Both PV and VIP BCs contributed to the increased sIPSC frequency in pyramidal neurons and optogenetic suppression of PV or VIP BCs inhibited sIPSCs occurring in the gamma range. Therefore, we propose acetylcholine release in CA1 has a complex effect on CA1 pyramidal neuron output through varying effects on perisomatically projecting interneurons. PMID:25556796

  17. Chicken embryo fibroblasts exposed to weak, time-varying magnetic fields share cell proliferation, adenosine deaminase activity, and membrane characteristics of transformed cells

    SciTech Connect

    Parola, A.H.; Porat, N.; Kiesow, L.A. )

    1993-01-01

    Chicken embryo fibroblasts (CEF) exposed to a sinusoidally varying magnetic field (SVMF) (100 Hz, 700 microT, for 24 h) showed a remarkable rise of segmental rotational relaxation rate of adenosine deaminase (ADA, EC 3.5.4.4) as determined by multifrequency phase fluorometry. Pyrene-labeled, small subunit ADA was applied to cultured (normal) CEF, which have available and abundant ADA complexing protein (ADCP) on their plasma membranes. Sine-wave-modulated fluorometry of the pyrene yielded a profile of phase angle vs. modulation frequency. In SVMF-treated cells and in Rous-sarcoma-virus (RSV) transformed cells the differential phase values at low modulation frequencies of the excitation are remarkably reduced. This effect is magnetic rather than thermal, because the temperature was carefully controlled and monitored; nevertheless to further check this matter we studied CEF, infected by the RSV-Ts68 temperature-sensitive mutant (36 degrees C transformed, 41 degrees C revertant). When grown at 36 degrees C in the SVMF, cells did not show the slightest trend towards reversion, as would be expected had there been local heating. Concomitant with the increased segmental rotational relaxation rate of ADA, there was a decrease in fluorescence lifetime and a slight, yet significant, increase in membrane lipid microfluidity. These biophysical observations prompted us to examine the effect of SVMF on cell proliferation and ADA activity (a malignancy marker): higher rates of cell proliferation and reduced specific activity of ADA were observed.

  18. The cross-sectional area of the gluteus maximus muscle varies according to habitual exercise loading: Implications for activity-related and evolutionary studies.

    PubMed

    Niinimäki, Sirpa; Härkönen, Laura; Nikander, Riku; Abe, Shinya; Knüsel, Christopher; Sievänen, Harri

    2016-04-01

    Greater size of the gluteus maximus muscle in humans compared to non-human primates has been considered an indication of its function in bipedal posture and gait, especially running capabilities. Our aim was to find out how the size of the gluteus maximus muscle varies according to sports while controlling for variation in muscle strength and body weight. Data on gluteus maximus muscle cross-sectional area (MCA) were acquired from magnetic resonance images of the hip region of female athletes (N=91), and physically active controls (N=20). Dynamic muscle force was measured as counter movement jump and isometric knee extension force as leg press. Five exercise loading groups were created: high impact (triple-jumpers and high-jumpers), odd impact (soccer and squash players), high magnitude (power-lifters), repetitive impact (endurance runners) and repetitive non-impact (swimmers) loadings. Individuals in high impact, odd impact or high-magnitude loading groups had greater MCA compared to those of controls, requiring powerful hip extension, trunk stabilization in rapid directional change and high explosive muscle force. Larger body size and greater muscle strength were associated with larger MCA. An increase in dynamic force was associated with larger MCA, but the strength of this relationship varied with body weight. Thus, gluteal adaptation in humans promotes powerful lower limb movements required in sprinting and rapid changes in direction, as well as maintenance and stabilization of an erect trunk which also provides a platform for powerful motions of the upper limbs. These movements have likely evolved to facilitate food acquisition, including hunting.

  19. NSC23766, a widely used inhibitor of Rac1 activation, additionally acts as a competitive antagonist at muscarinic acetylcholine receptors.

    PubMed

    Levay, Magdolna; Krobert, Kurt Allen; Wittig, Karola; Voigt, Niels; Bermudez, Marcel; Wolber, Gerhard; Dobrev, Dobromir; Levy, Finn Olav; Wieland, Thomas

    2013-10-01

    Small molecules interfering with Rac1 activation are considered as potential drugs and are already studied in animal models. A widely used inhibitor without reported attenuation of RhoA activity is NSC23766 [(N(6)-[2-[[4-(diethylamino)-1-methylbutyl]amino]-6-methyl-4-pyrimidinyl]-2-methyl-4,6-quinolinediamine trihydrochloride]. We found that NSC23766 inhibits the M2 muscarinic acetylcholine receptor (M2 mAChR)-induced Rac1 activation in neonatal rat cardiac myocytes. Surprisingly, NSC27366 concomitantly suppressed the carbachol-induced RhoA activation and a M2 mAChR-induced inotropic response in isolated neonatal rat hearts requiring the activation of Rho-dependent kinases. We therefore aimed to identify the mechanisms by which NSC23766 interferes with the differentially mediated, M2 mAChR-induced responses. Interestingly, NSC23766 caused a rightward shift of the carbachol concentration response curve for the positive inotropic response without modifying carbachol efficacy. To analyze the specificity of NSC23766, we compared the carbachol and the similarly Giβγ-mediated, adenosine-induced activation of Gi protein-regulated potassium channel (GIRK) channels in human atrial myocytes. Application of NSC23766 blocked the carbachol-induced K(+) current but had no effect on the adenosine-induced GIRK current. Similarly, an adenosine A1 receptor-induced positive inotropic response in neonatal rat hearts was not attenuated by NSC23766. To investigate its specificity toward the different mAChR types, we studied the carbachol-induced elevation of intracellular Ca(2+) concentrations in human embryonic kidney 293 (HEK-293) cells expressing M1, M2, or M3 mAChRs. NSC23766 caused a concentration-dependent rightward shift of the carbachol concentration response curves at all mAChRs. Thus, NSC23766 is not only an inhibitor of Rac1 activation, but it is within the same concentration range a competitive antagonist at mAChRs. Molecular docking analysis at M2 and M3 mAChR crystal

  20. Acute response of hypophysiotropic thyrotropin releasing hormone neurons and thyrotropin release to behavioral paradigms producing varying intensities of stress and physical activity.

    PubMed

    Gutiérrez-Mariscal, Mariana; Sánchez, Edith; García-Vázquez, Arlene; Rebolledo-Solleiro, Daniela; Charli, Jean-Louis; Joseph-Bravo, Patricia

    2012-11-10

    The activity of the hypothalamus-pituitary-thyroid (HPT) axis is essential for energy homeostasis and is differentially modulated by physical and by psychological stress. Contradictory effects of stressful behavioral paradigms on TSH or thyroid hormone release are due to type, length and controllability of the stressor. We hypothesized that an additional determinant of the activity of the HPT axis is the energy demand due to physical activity. We thus evaluated the response of thyrotropin releasing hormone (TRH) neurons of the hypothalamic paraventricular nucleus (PVN) in Wistar male rats submitted to the elevated plus maze (EPM), the open field test (OFT), or restraint, and sacrificed within 1h after test completion; the response to OFT was compared during light (L) or dark (D) phases. Locomotion and anxiety behaviors were similar if animals were tested in L or D phases but their relation to the biochemical parameters differed. All paradigms increased serum corticosterone concentration; the levels of corticotropin releasing hormone receptor 1 and of glucocorticoid receptor (GR) mRNAs in the PVN were enhanced after restraint or OFT-L. Levels of proTRH mRNA increased in the PVN after exposure to EPM-L or OFT-D; serum levels of thyrotropin (TSH) and T(4) only after OFT-D. In contrast, restraint decreased TRH mRNA and serum TSH levels, while it increased TRH content in the mediobasal hypothalamus, implying reduced release. Expression of proTRH in the PVN varied proportionally to the degree of locomotion in OFT-D, while inversely to anxiety in the EPM-L, and to corticosterone in EPM-L and OFT-D. TRH mRNA levels were analyzed by in situ hybridization in the rostral, middle and caudal zones of the PVN in response to OFT-D; they increased in the middle PVN, where most TRH hypophysiotropic neurons reside; levels correlated positively with the velocity attained in the periphery of the OF and negatively, with anxiety. Variations of serum TSH levels correlated positively with

  1. Handling qualities of a wide-body transport airplane utilizing Pitch Active Control Systems (PACS) for relaxed static stability application

    NASA Technical Reports Server (NTRS)

    Grantham, William D.; Person, Lee H., Jr.; Brown, Philip W.; Becker, Lawrence E.; Hunt, George E.; Rising, J. J.; Davis, W. J.; Willey, C. S.; Weaver, W. A.; Cokeley, R.

    1985-01-01

    Piloted simulation studies have been conducted to evaluate the effectiveness of two pitch active control systems (PACS) on the flying qualities of a wide-body transport airplane when operating at negative static margins. These two pitch active control systems consisted of a simple 'near-term' PACS and a more complex 'advanced' PACS. Eight different flight conditions, representing the entire flight envelope, were evaluated with emphasis on the cruise flight conditions. These studies were made utilizing the Langley Visual/Motion Simulator (VMS) which has six degrees of freedom. The simulation tests indicated that (1) the flying qualities of the baseline aircraft (PACS off) for the cruise and other high-speed flight conditions were unacceptable at center-of-gravity positions aft of the neutral static stability point; (2) within the linear static stability flight envelope, the near-term PACS provided acceptable flying qualities for static stabilty margins to -3 percent; and (3) with the advanced PACS operative, the flying qualities were demonstrated to be good (satisfactory to very acceptable) for static stabilty margins to -20 percent.

  2. Reconstructing genome-wide regulatory network of E. coli using transcriptome data and predicted transcription factor activities

    PubMed Central

    2011-01-01

    Background Gene regulatory networks play essential roles in living organisms to control growth, keep internal metabolism running and respond to external environmental changes. Understanding the connections and the activity levels of regulators is important for the research of gene regulatory networks. While relevance score based algorithms that reconstruct gene regulatory networks from transcriptome data can infer genome-wide gene regulatory networks, they are unfortunately prone to false positive results. Transcription factor activities (TFAs) quantitatively reflect the ability of the transcription factor to regulate target genes. However, classic relevance score based gene regulatory network reconstruction algorithms use models do not include the TFA layer, thus missing a key regulatory element. Results This work integrates TFA prediction algorithms with relevance score based network reconstruction algorithms to reconstruct gene regulatory networks with improved accuracy over classic relevance score based algorithms. This method is called Gene expression and Transcription factor activity based Relevance Network (GTRNetwork). Different combinations of TFA prediction algorithms and relevance score functions have been applied to find the most efficient combination. When the integrated GTRNetwork method was applied to E. coli data, the reconstructed genome-wide gene regulatory network predicted 381 new regulatory links. This reconstructed gene regulatory network including the predicted new regulatory links show promising biological significances. Many of the new links are verified by known TF binding site information, and many other links can be verified from the literature and databases such as EcoCyc. The reconstructed gene regulatory network is applied to a recent transcriptome analysis of E. coli during isobutanol stress. In addition to the 16 significantly changed TFAs detected in the original paper, another 7 significantly changed TFAs have been detected by

  3. Surface modification of CoCr alloy using varying concentrations of phosphoric and phosphonoacetic acids: albumin and fibrinogen adsorption, platelet adhesion, activation, and aggregation studies.

    PubMed

    Thiruppathi, Eagappanath; Larson, Mark K; Mani, Gopinath

    2015-01-01

    CoCr alloy is commonly used in various cardiovascular medical devices for its excellent physical and mechanical properties. However, the formation of blood clots on the alloy surfaces is a serious concern. This research is focused on the surface modification of CoCr alloy using varying concentrations (1, 25, 50, 75, and 100 mM) of phosphoric acid (PA) and phosphonoacetic acid (PAA) to generate various surfaces with different wettability, chemistry, and roughness. Then, the adsorption of blood plasma proteins such as albumin and fibrinogen and the adhesion, activation, and aggregation of platelets with the various surfaces generated were investigated. Contact angle analysis showed PA and PAA coatings on CoCr provided a gradient of hydrophilic surfaces. FTIR showed PA and PAA were covalently bound to CoCr surface and formed different bonding configurations depending on the concentrations of coating solutions used. AFM showed the formation of homogeneous PA and PAA coatings on CoCr. The single and dual protein adsorption studies showed that the amount of albumin and fibrinogen adsorbed on the alloy surfaces strongly depend on the type of PA and PAA coatings prepared by different concentrations of coating solutions. All PA coated CoCr showed reduced platelet adhesion and activation when compared to control CoCr. Also, 75 and 100 mM PA-CoCr showed reduced platelet aggregation. For PAA coated CoCr, no significant difference in platelet adhesion and activation was observed between PAA coated CoCr and control CoCr. Thus, this study demonstrated that CoCr can be surface modified using PA for potentially reducing the formation of blood clots and improving the blood compatibility of the alloy.

  4. The effect of varying dietary starch and fat content on serum creatine kinase activity and substrate availability in equine polysaccharide storage myopathy.

    PubMed

    Ribeiro, W P; Valberg, S J; Pagan, J D; Gustavsson, B Essen

    2004-01-01

    The effect of dietary starch and fat content on serum creatine kinase (CK) activity and substrate availability was evaluated in 4 mares of Quarter Horse-related breeds with polysaccharide storage myopathy (PSSM). Four isocaloric diets ranging in digestible energy (DE) from 21.2% (diet A), 14.8% (B), 8.4% (C), to 3.9% (D) for starch, and 7.2% DE (diet A), 9.9% (B), to 12.7% DE (diet C and D) for fat were fed for 6-week periods (4 weeks with exercise) using a 4 X 4 Latin square design. Postprandial glucose and insulin responses were measured, and 4 hours postexercise, serum CK activity, glucose, insulin, free fatty acids (FFA), and beta-hydroxybutyrate (beta-HBA) were analyzed. Glycogen, glucose-6-phosphate, citrate synthase, 3-hydroxy-acyl-CoA dehydrogenase, lactate dehydrogenase as well as abnormal polysaccharide and lipid content were measured in middle gluteal muscle samples. Postprandial insulin and glucose response was higher for diet A versus D. Log CK activity was higher with diets A, B, and C versus D. Daily insulin was higher and FFA lower on diet A versus B, C, and D, whereas glucose varied only slightly with diet. Muscle oxidative capacity and lipid stores were low in PSSM horses and muscle glycogen and abnormal polysaccharide content high on both diets A and D. Individual variation occurred in the response of PSSM horses to diets differing in starch and fat content. However, for those horses with clinical manifestations of PSSM, a diet with <5% DE starch and >12% DE fat can reduce exertional rhabdomyolysis, potentially by increasing availability of FFA for muscle metabolism.

  5. Biochemical changes in the liver and gill of Cathorops spixii collected seasonally in two Brazilian estuaries under varying influences of anthropogenic activities.

    PubMed

    Azevedo, J S; Braga, E S; Silva de Assis, H C; Oliveira Ribeiro, C A

    2013-10-01

    In order to understand environmental health by the use of a bioindicator species in estuaries, biochemical responses observed in the catfish Cathorops spixii such as catalase (CAT), glutathione-S-transferase (GST), lipid peroxidation (LPO) and acetylcholinesterase (AChE) were evaluated in liver and muscle. Furthermore, histological changes were also verified in liver and gills preparations. Fish were collected in three sites of the Santos-São Vicente estuary located at São Paulo (Brazil), subjected to varying levels of inputs of pollutants. For a reference site, specimens were sampled at Cananéia estuary at southern coast of São Paulo, a region with low anthropogenic influence. In general, no significant seasonal differences in antioxidant enzymes and lipid peroxidation responses were found in the organisms from the Cananéia estuary. However, in the polluted estuary (Santos-São Vicente), biochemical responses were observed by increases in GST hydroperoxides and decreases in AChE activities in the summer. Inhibition of AChE expression in fish from different areas of the Santos-São Vicente estuary in the summer was also found and can indicate neurotoxic effects in these organisms. Histopathological observation of gill and liver showed severe lesions, such as lamellar fusion and necrosis.

  6. Rat long-chain acyl-CoA synthetase mRNA, protein, and activity vary in tissue distribution and in response to diet.

    PubMed

    Mashek, Douglas G; Li, Lei O; Coleman, Rosalind A

    2006-09-01

    Distinct isoforms of long-chain acyl-CoA synthetases (ACSLs) may partition fatty acids toward specific metabolic cellular pathways. For each of the five members of the rat ACSL family, we analyzed tissue mRNA distributions, and we correlated the mRNA, protein, and activity of ACSL1 and ACSL4 after fasting and refeeding a 69% sucrose diet. Not only did quantitative real-time PCR analyses reveal unique tissue expression patterns for each ACSL isoform, but expression varied markedly in different adipose depots. Fasting increased ACSL4 mRNA abundance in liver, muscle, and gonadal and inguinal adipose tissues, and refeeding decreased ACSL4 mRNA. A similar pattern was observed for ACSL1, but both fasting and refeeding decreased ACSL1 mRNA in gonadal adipose. Fasting also decreased ACSL3 and ACSL5 mRNAs in liver and ACSL6 mRNA in muscle. Surprisingly, in nearly every tissue measured, the effects of fasting and refeeding on the mRNA abundance of ACSL1 and ACSL4 were discordant with changes in protein abundance. These data suggest that the individual ACSL isoforms are distinctly regulated across tissues and show that mRNA expression may not provide useful information about isoform function. They further suggest that translational or posttranslational modifications are likely to contribute to the regulation of ACSL isoforms.

  7. Active optics and modified-Rumsey wide-field telescopes: MINITRUST demonstrators with vase- and tulip-form mirrors

    NASA Astrophysics Data System (ADS)

    Lemaître, Gérard R.; Montiel, Pierre; Joulié, Patrice; Dohlen, Kjetil; Lanzoni, Patrick

    2005-12-01

    Wide-field astronomy requires the development of larger aperture telescopes. The optical properties of a three-mirror modified-Rumsey design provide significant advantages when compared to other telescope designs: (i) at any wavelength, the design has a flat field and is anastigmatic; (ii) the system is extremely compact, i.e., it is almost four times shorter than a Schmidt. Compared to the equally compact flat-field Ritchey-Chrétien with a doublet-lens corrector, as developed for the Sloan digital sky survey - and which requires the polishing of six optical surfaces - the proposed modified-Rumsey design requires only a two-surface polishing and provides a better imaging quality. All the mirrors are spheroids of the hyperboloid type. Starting from the classical Rumsey design, it is shown that the use of all eight available free parameters allows the simultaneous aspherization of the primary and tertiary mirrors by active optics methods from a single deformable substrate. The continuity conditions between the primary and the tertiary hyperbolizations are achieved by an intermediate narrow ring of constant thickness that is not optically used. After the polishing of a double vase form in a spherical shape, the primary-tertiary hyperbolizations are achieved by in situ stressing. The tulip-form secondary is hyperbolized by stress polishing. Other active optics alternatives are possible for a space telescope. The modified-Rumsey design is of interest for developing large space- and ground-based survey telescopes in UV, visible, or IR ranges, such as currently demonstrated with the construction of identical telescopes MINITRUST-1 and -2, f/5 - 2° field of view. Double-pass optical tests show diffraction-limited images.

  8. Alzheimer's Disease Variants with the Genome-Wide Significance are Significantly Enriched in Immune Pathways and Active in Immune Cells.

    PubMed

    Jiang, Qinghua; Jin, Shuilin; Jiang, Yongshuai; Liao, Mingzhi; Feng, Rennan; Zhang, Liangcai; Liu, Guiyou; Hao, Junwei

    2017-01-01

    The existing large-scale genome-wide association studies (GWAS) datasets provide strong support for investigating the mechanisms of Alzheimer's disease (AD) by applying multiple methods of pathway analysis. Previous studies using selected single nucleotide polymorphisms (SNPs) with several thresholds of nominal significance for pathway analysis determined that the threshold chosen for SNPs can reflect the disease model. Presumably, then, pathway analysis with a stringent threshold to define "associated" SNPs would test the hypothesis that highly associated SNPs are enriched in one or more particular pathways. Here, we selected 599 AD variants (P < 5.00E-08) to investigate the pathways in which these variants are enriched and the cell types in which these variants are active. Our results showed that AD variants are significantly enriched in pathways of the immune system. Further analysis indicated that AD variants are significantly enriched for enhancers in a number of cell types, in particular the B-lymphocyte, which is the most substantially enriched cell type. This cell type maintains its dominance among the strongest enhancers. AD SNPs also display significant enrichment for DNase in 12 cell types, among which the top 6 significant signals are from immune cell types, including 4 B cells (top 4 significant signals) and CD14+ and CD34+ cells. In summary, our results show that these AD variants with P < 5.00E-08 are significantly enriched in pathways of the immune system and active in immune cells. To a certain degree, the genetic predisposition for development of AD is rooted in the immune system, rather than in neuronal cells.

  9. Active optics and modified-Rumsey wide-field telescopes: MINITRUST demonstrators with vase- and tulip-form mirrors.

    PubMed

    Lemaître, Gérard R; Montiel, Pierre; Joulié, Patrice; Dohlen, Kjetil; Lanzoni, Patrick

    2005-12-01

    Wide-field astronomy requires the development of larger aperture telescopes. The optical properties of a three-mirror modified-Rumsey design provide significant advantages when compared to other telescope designs: (i) at any wavelength, the design has a flat field and is anastigmatic; (ii) the system is extremely compact, i.e., it is almost four times shorter than a Schmidt. Compared to the equally compact flat-field Ritchey-Chrétien with a doublet-lens corrector, as developed for the Sloan digital sky survey-and which requires the polishing of six optical surfaces-the proposed modified-Rumsey design requires only a two-surface polishing and provides a better imaging quality. All the mirrors are spheroids of the hyperboloid type. Starting from the classical Rumsey design, it is shown that the use of all eight available free parameters allows the simultaneous aspherization of the primary and tertiary mirrors by active optics methods from a single deformable substrate. The continuity conditions between the primary and the tertiary hyperbolizations are achieved by an intermediate narrow ring of constant thickness that is not optically used. After the polishing of a double vase form in a spherical shape, the primary-tertiary hyperbolizations are achieved by in situ stressing. The tulip-form secondary is hyperbolized by stress polishing. Other active optics alternatives are possible for a space telescope. The modified-Rumsey design is of interest for developing large space- and ground-based survey telescopes in UV, visible, or IR ranges, such as currently demonstrated with the construction of identical telescopes MINITRUST-1 and -2, f/5-2 degrees field of view. Double-pass optical tests show diffraction-limited images.

  10. 2MASS 0213+3648 C: A wide T3 benchmark companion to an an active, old M dwarf binary

    NASA Astrophysics Data System (ADS)

    Deacon, N. R.; Magnier, E. A.; Liu, Michael C.; Schlieder, Joshua E.; Aller, Kimberly M.; Best, William M. J.; Bowler, Brendan P.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Metcalfe, N.; Sweeney, W. E.; Wainscoat, R. J.; Waters, C.

    2017-01-01

    We present the discovery of a 360 AU separation T3 companion to the tight (3.1 AU) M4.5+M6.5 binary 2MASS J02132062+3648506. This companion was identified using Pan-STARRS 1 data and, despite its relative proximity to the Sun (22.2_{-4.0}^{+6.4} pc; Pan-STARRS 1 parallax) and brightness (J=15.3), appears to have been missed by previous studies due to its position near a diffraction spike in 2MASS. The close M dwarf binary has active X-ray and Hα emission and shows evidence for UV flares. The binary's weak GALEX UV emission and strong Na I 8200 Å Na absorption leads us to an age range of ˜1-10 Gyr. Applying this age range to evolutionary models implies the wide companion has a mass of 0.063±0.009 M⊙. 2MASS J0213+3648 C provides a relatively old benchmark close to the L/T transition and acts as a key, older comparison to the much younger early-T companions HN Peg B and GU Psc b.

  11. Acidobacteria dominate the active bacterial communities of Arctic tundra with widely divergent winter-time snow accumulation and soil temperatures.

    PubMed

    Männistö, Minna K; Kurhela, Emilia; Tiirola, Marja; Häggblom, Max M

    2013-04-01

    The timing and extent of snow cover is a major controller of soil temperature and hence winter-time microbial activity and plant diversity in Arctic tundra ecosystems. To understand how snow dynamics shape the bacterial communities, we analyzed the bacterial community composition of windswept and snow-accumulating shrub-dominated tundra heaths of northern Finland using DNA- and RNA-based 16S rRNA gene community fingerprinting (terminal restriction fragment polymorphism) and clone library analysis. Members of the Acidobacteria and Proteobacteria dominated the bacterial communities of both windswept and snow-accumulating habitats with the most abundant phylotypes corresponding to subdivision (SD) 1 and 2 Acidobacteria in both the DNA- and RNA-derived community profiles. However, different phylotypes within Acidobacteria were found to dominate at different sampling dates and in the DNA- vs. RNA-based community profiles. The results suggest that different species within SD1 and SD2 Acidobacteria respond to environmental conditions differently and highlight the wide functional diversity of these organisms even within the SD level. The acidic tundra soils dominated by ericoid shrubs appear to select for diverse stress-tolerant Acidobacteria that are able to compete in the nutrient poor, phenolic-rich soils. Overall, these communities seem stable and relatively insensitive to the predicted changes in the winter-time snow cover.

  12. Changes in the flavonoid and phenolic acid contents and antioxidant activity of red leaf lettuce (Lollo Rosso) due to cultivation under plastic films varying in ultraviolet transparency.

    PubMed

    García-Macías, Paulina; Ordidge, Matthew; Vysini, Eleni; Waroonphan, Saran; Battey, Nicholas H; Gordon, Michael H; Hadley, Paul; John, Philip; Lovegrove, Julie A; Wagstaffe, Alexandra

    2007-12-12

    Red leaf lettuce (Lollo Rosso) was grown under three types of plastic films that varied in transparency to UV radiation (designated as UV block, UV low, and UV window). Flavonoid composition was determined by high-performance liquid chromatography (HPLC), total phenolics by the Folin-Ciocalteu assay, and antioxidant capacity by the oxygen radical absorbance capacity (ORAC) assay. Exposure to increased levels of UV radiation during cultivation caused the leaves to redden and increased concentrations of total phenols and the main flavonoids, quercetin and cyanidin glycosides, as well as luteolin conjugates and phenolic acids. The total phenol content increased from 1.6 mg of gallic acid equivalents (GAE)/g of fresh weight (FW) for lettuce grown under UV block film to 2.9 and 3.5 mg of GAE/g of FW for lettuce grown under the UV low and UV window films. The antioxidant activity was also higher in lettuce exposed to higher levels of UV radiation with ORAC values of 25.4 and 55.1 micromol of Trolox equivalents/g of FW for lettuce grown under the UV block and UV window films, respectively. The content of phenolic acids, quantified as caffeic acid, was also different, ranging from 6.2 to 11.1 micromol/g of FW for lettuce cultivated under the lowest and highest UV exposure plastic films, respectively. Higher concentrations of the flavonoid glycosides were observed with increased exposure to UV radiation, as demonstrated by the concentrations of aglycones after hydrolysis, which were cyanidin (ranging from 165 to 793 microg/g), quercetin (ranging from 196 to 880 microg/g), and luteolin (ranging from 19 to 152 microg/g). The results demonstrate the potential of the use of UV-transparent plastic as a means of increasing beneficial flavonoid content of red leaf lettuce when the crop is grown in polytunnels.

  13. A low-temperature-active alkaline pectate lyase from Xanthomonas campestris ACCC 10048 with high activity over a wide pH range.

    PubMed

    Yuan, Peng; Meng, Kun; Wang, Yaru; Luo, Huiying; Shi, Pengjun; Huang, Huoqing; Tu, Tao; Yang, Peilong; Yao, Bin

    2012-11-01

    Alkaline pectate lyases are favorable for the textile industry. Here, we report the gene cloning and expression of a low-temperature-active alkaline pectate lyase (PL D) from Xanthomonas campestris ACCC 10048. Deduced PL D consists of a putative 27-residue signal peptide and a catalytic domain of 320 residues belonging to family PF09492. Recombinant PL D (r-PL D) produced in Escherichia coli was purified to electrophoretic homogeneity with a single step of Ni(2+)-NTA affinity chromatography and showed an apparent molecular weight of ~38 kDa. The pH and temperature optima of r-PL D were found to be 9.0 °C and 30 °C, respectively. Compared with its microbial counterparts, r-PL D had higher activity over a wide pH range (>45 % of the maximum activity at pH 3.0-12.0) and at lower temperatures (>35 % of activity even at 0 °C). The K(m) and V(max) values of r-PL D for polygalacturonic acid were 4.9 gl(-1) and 30.1 μmolmin(-1) mg(-1), respectively. Compared with the commercial compound pectinase from Novozymes, r-PL D showed similar efficacy in reducing the intrinsic viscosity of polygalacturonic acid (35.1 % vs. 36.5 %) and in bioscouring of jute (10.25 % vs. 10.82 %). Thus, r-PL D is a valuable additive candidate for the textile industry.

  14. Genome-wide identification and transcriptional expression analysis of mitogen-activated protein kinase and mitogen-activated protein kinase kinase genes in Capsicum annuum

    PubMed Central

    Liu, Zhiqin; Shi, Lanping; Liu, Yanyan; Tang, Qian; Shen, Lei; Yang, Sheng; Cai, Jinsen; Yu, Huanxin; Wang, Rongzhang; Wen, Jiayu; Lin, Youquan; Hu, Jiong; Liu, Cailing; Zhang, Yangwen; Mou, Shaoliang; He, Shuilin

    2015-01-01

    The tripartite mitogen-activated protein kinase (MAPK) signaling cascades have been implicated in plant growth, development, and environment adaptation, but a comprehensive understanding of MAPK signaling at genome-wide level is limited in Capsicum annuum. Herein, genome-wide identification and transcriptional expression analysis of MAPK and MAPK kinase (MAPKK) were performed in pepper. A total of 19 pepper MAPK (CaMAPKs) genes and five MAPKK (CaMAPKKs) genes were identified. Phylogenetic analysis indicated that CaMAPKs and CaMAPKKs could be classified into four groups and each group contains similar exon-intron structures. However, significant divergences were also found. Notably, five members of the pepper MAPKK family were much less conserved than those found in Arabidopsis, and 9 Arabidopsis MAPKs did not have orthologs in pepper. Additionally, 7 MAPKs in Arabidopsis had either two or three orthologs in the pepper genome, and six pepper MAPKs and one MAPKK differing in sequence were found in three pepper varieties. Quantitative real-time RT-PCR analysis showed that the majority of MAPK and MAPKK genes were ubiquitously expressed and transcriptionally modified in pepper leaves after treatments with heat, salt, and Ralstonia solanacearum inoculation as well as exogenously applied salicylic acid, methyl jasmonate, ethephon, and abscisic acid. The MAPKK-MAPK interactome was tested by yeast two-hybrid assay, the results showed that one MAPKK might interact with multiple MAPKs, one MAPK might also interact with more than one MAPKKs, constituting MAPK signaling networks which may collaborate in transmitting upstream signals into appropriate downstream cellular responses and processes. These results will facilitate future functional characterization of MAPK cascades in pepper. PMID:26442088

  15. Enhancing Student Performance in First-Semester General Chemistry Using Active Feedback through the World Wide Web

    ERIC Educational Resources Information Center

    Chambers, Kent A.; Blake, Bob

    2007-01-01

    The World Wide Web recently launched a new interactive feedback system for the instructors, so that can better understanding about their students and their problems. The feedback, in combination with tailored lectures is expected to enhance student performance in the first semester of general chemistry.

  16. What Would You Like? Identifying the Required Characteristics of an Industry-Wide Incident Reporting and Learning System for the Led Outdoor Activity Sector

    ERIC Educational Resources Information Center

    Goode, Natassia; Finch, Caroline F.; Cassell, Erin; Lenne, Michael G.; Salmon, Paul M.

    2014-01-01

    The aim of this study was to identify the characteristics that led outdoor activity providers agree are necessary for the development of a new industry-wide incident reporting and learning system (UPLOADS). The study involved: 1) a literature review to identify a set of characteristics that are considered to be hallmarks of successful reporting…

  17. Alterations in activities of acid phosphatase, alkaline phosphatase, ATPase and ATP content in response to seasonally varying Pi status in okra (Abelmoschus esculentus).

    PubMed

    Sen, Supatra; Mukherji, S

    2004-04-01

    Phosphorus (P) is the second most important macronutrient for plant growth. Plants exhibit numerous physiological and metabolic adaptations in response to seasonal variations in phosphorus content. Activities of acid and alkaline phosphatases, ATPase and ATP content were studied in summer, rainy and winter seasons at two different developmental stages (28 and 58 days after sowing) in Okra. Activities of both acid and alkaline phosphatases increased manifold in winter to cope up with low phosphorus content. ATP content and ATPase activity were high in summer signifying an active metabolic period. Phosphorus deficiency is characterized by low ATP content and ATPase activity (which are in turn partly responsible for a drastic reduction in growth and yield) and enhanced activities of acid and alkaline phosphatases which increase the availability of P in P-deficient seasons.

  18. Fluorosis varied treatment options

    PubMed Central

    Sherwood, I Anand

    2010-01-01

    Fluorosis has been reported way back in 1901. The treatment options for fluorosis are varied depending upon individual cases. This article comes from Madurai in India where its surrounding towns are fluorosis-prone zones. The purpose of this article is to report various treatment options available for dental fluorosis; this is the first time that complete full mouth rehabilitation for dental fluorosis is being reported. This article also dwells on the need for the dentists to be aware of their local indigenous pathologies to treat it in a better manner. PMID:20582220

  19. Antioxidant Activity and Phenolic Content of Defatted Buckwheat (Fagopyrum esculentum Moench) Flour in Water or Ethanol Heated using Microwave Irradiation at Varying Temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Buckwheat (Fagopyrum esculentum) has potential to be a nutritionally beneficial crop due to its high phenolic content and antioxidant activity. We explored new technologies to enhance buckwheat phenolic content and antioxidant activity. Buckwheat achenes were ground and flour was extracted for 15 ...

  20. Single-trial estimation of stimulus and spike-history effects on time-varying ensemble spiking activity of multiple neurons: a simulation study

    NASA Astrophysics Data System (ADS)

    Shimazaki, Hideaki

    2013-12-01

    Neurons in cortical circuits exhibit coordinated spiking activity, and can produce correlated synchronous spikes during behavior and cognition. We recently developed a method for estimating the dynamics of correlated ensemble activity by combining a model of simultaneous neuronal interactions (e.g., a spin-glass model) with a state-space method (Shimazaki et al. 2012 PLoS Comput Biol 8 e1002385). This method allows us to estimate stimulus-evoked dynamics of neuronal interactions which is reproducible in repeated trials under identical experimental conditions. However, the method may not be suitable for detecting stimulus responses if the neuronal dynamics exhibits significant variability across trials. In addition, the previous model does not include effects of past spiking activity of the neurons on the current state of ensemble activity. In this study, we develop a parametric method for simultaneously estimating the stimulus and spike-history effects on the ensemble activity from single-trial data even if the neurons exhibit dynamics that is largely unrelated to these effects. For this goal, we model ensemble neuronal activity as a latent process and include the stimulus and spike-history effects as exogenous inputs to the latent process. We develop an expectation-maximization algorithm that simultaneously achieves estimation of the latent process, stimulus responses, and spike-history effects. The proposed method is useful to analyze an interaction of internal cortical states and sensory evoked activity.

  1. Time Varying Feature Data

    NASA Astrophysics Data System (ADS)

    Echterhoff, J.; Simonis, I.; Atkinson, R.

    2012-04-01

    The infrastructure to gather, store and access information about our environment is improving and growing rapidly. The increasing amount of information allows us to get a better understanding of the current state of our environment, historical processes and to simulate and predict the future state of the environment. Finer grained spatial and temporal data and more reliable communications make it easier to model dynamic states and ephemeral features. The exchange of information within and across geospatial domains is facilitated through the use of harmonized information models. The Observations & Measurements (O&M) developed through OGC and standardised by ISO is an example of such a cross-domain information model. It is used in many domains, including meteorology, hydrology as well as the emergency management. O&M enables harmonized representation of common metadata that belong to the act of determining the state of a feature property, whether by sensors, simulations or humans. In addition to the resulting feature property value, information such as the result quality but especially the time that the result applies to the feature property can be represented. Temporal metadata is critical to modelling past and future states of a feature. The features, and the semantics of each property, are defined in domain specific Application Schema using the General Feature Model (GFM) from ISO 19109 and usually encoded following ISO 19136. However, at the moment these standards provide only limited support for the representation and handling of time varying feature data. Features like rivers, wildfires or gas plumes have a defined state - for example geographic extent - at any given point in time. To keep track of changes, a more complex model for example using time-series coverages is required. Furthermore, the representation and management of feature property value changes via the service interfaces defined by OGC and ISO - namely: WFS and WCS - would be rather complex

  2. Brain activations evoked by tactile stimulation varies with the intensity and not with number of receptive fields stimulated: An fMRI study

    NASA Astrophysics Data System (ADS)

    Ramirez Garzón, Y. T.; Pasaye, E. H.; Barrios, F. A.

    2014-11-01

    Using functional Magnetic Resonance Imaging (fMRI) it is possible to study the functional anatomy of primary cortices. Cortical representations in the primary somatosensory cortex have shown discrepancies between activations related to the same body region in some studies; these differences have been more pronounced for lower limb representations. The aim of this study was to observe the influence of the tactile stimulus intensity in somatosensory cortical responses using fMRI. Based in the sensitivity and pain threshold of each subject, we used Von Frey filaments for stimulate 12 control subject in three receptive fields on the right thigh. One filament near to sensitivity threshold (VFS), other close to pain threshold (VFP) and one intermediate filament between the two previous thresholds (VFI). The tactile stimulation with VFS produced no activation on SI, while that the contralateral SI was activated by stimulation with VFI in 5 subjects and with the stimulation of VFP in all subjects. Second level statistical analysis showed significant differences between SI activations related to the stimulation with VFP and VFI (VFP > VFI), in the comparison between the applied different intensities, a small cluster of activation was observed on SI for the unique possible contrast (VFP > VFI). The time course per trial for each subject was extracted and averaged to extract the activation in the contralateral SI and compared across the stimulus modalities, between the sites of field receptive stimulated and the intensities used. The time course of tactile stimulus responses revealed a consistent single peak of activity per cycle (30 s), approximately 12 s after the onset of the stimulus, with exception of the VFI stimulation,_which showed the peak at 10 s. Thus, our results indicate that the cortical representation of a tactile stimulus with fMRI is modulated for the intensity of the stimulus applied.

  3. Altered erythrocyte C3b receptor expression, immune complexes, and complement activation in homosexual men in varying risk groups for acquired immune deficiency syndrome.

    PubMed Central

    Tausk, F A; McCutchan, A; Spechko, P; Schreiber, R D; Gigli, I

    1986-01-01

    We studied levels of erythrocyte C3b receptors (E-CR1) and correlated them to the level of circulating immune complexes (CIC) and complement activation in patients with or at risk for acquired immunodeficiency syndrome (AIDS). A significant reduction was found in patients with AIDS (185 +/- 93 CR1/cell), AIDS-related complex, and generalized lymphadenopathy, whereas healthy male homosexuals or normal controls had 434 +/- 193 and 509 +/- 140 CR1/cell, respectively (P less than 0.001). Family studies indicate that this defect is acquired. Reduction in E-CR1 was associated with increased levels of CIC when assayed by binding to Raji cells, but not when tested by C1q binding. Complement activation was assessed by levels of C3bi/C3d-g in plasma, measured with a monoclonal antibody specific for a neoantigen in C3d. AIDS patients had increased C3 activation (2.68 +/- 1.67%) when compared with normal controls (0.9 +/- 0.22%) (P less than 0.01). The decreased E-CR1, the presence of CIC, and C3 activation suggest that complement activation by immune complexes may play a role in the clinical expression of the disease. PMID:2944915

  4. Genome-Wide Single-Cell Analysis of Recombination Activity and de novo Mutation Rates in Human Sperm

    PubMed Central

    Wang, Jianbin; Fan, H. Christina; Behr, Barry; Quake, Stephen R.

    2012-01-01

    SUMMARY Meiotic recombination and de novo mutation are the two main contributions towards gamete genome diversity, and many questions remain about how an individual human’s genome is edited by these two processes. Here, we describe a high-throughput method for single-cell whole-genome analysis which was used to measure the genomic diversity in one individual’s gamete genomes. A microfluidic system was used for highly parallel sample processing and to minimize non-specific amplification. High-density genotyping results from 91 single cells were used to create a personal recombination map, which was consistent with population-wide data at low resolution but revealed significant differences from pedigree data at higher resolution. We used the data to test for meiotic drive and found evidence for gene conversion. High throughput sequencing on 31 single cells was used to measure the frequency of large-scale genome instability, and deeper sequencing of eight single cells revealed de novo mutation rates with distinct characteristics. PMID:22817899

  5. Geothrix fermentans Secretes Two Different Redox-Active Compounds To Utilize Electron Acceptors across a Wide Range of Redox Potentials

    PubMed Central

    Mehta-Kolte, Misha G.

    2012-01-01

    The current understanding of dissimilatory metal reduction is based primarily on isolates from the proteobacterial genera Geobacter and Shewanella. However, environments undergoing active Fe(III) reduction often harbor less-well-studied phyla that are equally abundant. In this work, electrochemical techniques were used to analyze respiratory electron transfer by the only known Fe(III)-reducing representative of the Acidobacteria, Geothrix fermentans. In contrast to previously characterized metal-reducing bacteria, which typically reach maximal rates of respiration at electron acceptor potentials of 0 V versus standard hydrogen electrode (SHE), G. fermentans required potentials as high as 0.55 V to respire at its maximum rate. In addition, G. fermentans secreted two different soluble redox-active electron shuttles with separate redox potentials (−0.2 V and 0.3 V). The compound with the lower midpoint potential, responsible for 20 to 30% of electron transfer activity, was riboflavin. The behavior of the higher-potential compound was consistent with hydrophilic UV-fluorescent molecules previously found in G. fermentans supernatants. Both electron shuttles were also produced when cultures were grown with Fe(III), but not when fumarate was the electron acceptor. This study reveals that Geothrix is able to take advantage of higher-redox-potential environments, demonstrates that secretion of flavin-based shuttles is not confined to Shewanella, and points to the existence of high-potential-redox-active compounds involved in extracellular electron transfer. Based on differences between the respiratory strategies of Geothrix and Geobacter, these two groups of bacteria could exist in distinctive environmental niches defined by redox potential. PMID:22843516

  6. Transcriptomic-Wide Discovery of Direct and Indirect HuR RNA Targets in Activated CD4+ T Cells

    PubMed Central

    Techasintana, Patsharaporn; Davis, J. Wade; Gubin, Matthew M.; Magee, Joseph D.; Atasoy, Ulus

    2015-01-01

    Due to poor correlation between steady state mRNA levels and protein product, purely transcriptomic profiling methods may miss genes posttranscriptionally regulated by RNA binding proteins (RBPs) and microRNAs (miRNAs). RNA immunoprecipitation (RIP) methods developed to identify in vivo targets of RBPs have greatly elucidated those mRNAs which may be regulated via transcript stability and translation. The RBP HuR (ELAVL1) and family members are major stabilizers of mRNA. Many labs have identified HuR mRNA targets; however, many of these analyses have been performed in cell lines and oftentimes are not independent biological replicates. Little is known about how HuR target mRNAs behave in conditional knock-out models. In the present work, we performed HuR RIP-Seq and RNA-Seq to investigate HuR direct and indirect targets using a novel conditional knock-out model of HuR genetic ablation during CD4+ T activation and Th2 differentiation. Using independent biological replicates, we generated a high coverage RIP-Seq data set (>160 million reads) that was analyzed using bioinformatics methods specifically designed to find direct mRNA targets in RIP-Seq data. Simultaneously, another set of independent biological replicates were sequenced by RNA-Seq (>425 million reads) to identify indirect HuR targets. These direct and indirect targets were combined to determine canonical pathways in CD4+ T cell activation and differentiation for which HuR plays an important role. We show that HuR may regulate genes in multiple canonical pathways involved in T cell activation especially the CD28 family signaling pathway. These data provide insights into potential HuR-regulated genes during T cell activation and immune mechanisms. PMID:26162078

  7. Potential of peroxisome proliferator-activated receptor gamma antagonist compounds as therapeutic agents for a wide range of cancer types.

    PubMed

    Burton, Jack D; Goldenberg, David M; Blumenthal, Rosalyn D

    2008-01-01

    PPARgamma is a therapeutic target that has been exploited for treatment of type II diabetes mellitus (T2DM) with agonist drugs. Since PPARgamma is expressed by many hematopoietic, mesodermal and epithelial cancers, agonist drugs were tested and shown to have both preclinical and clinical anticancer activities. While preclinical activity has been observed in many cancer types, clinical activity has been observed only in pilot and phase II trials in liposarcoma and prostate cancer. Most studies address agonist compounds, with substantially fewer reports on anticancer effects of PPARgamma antagonists. In cancer model systems, some effects of PPARgamma agonists were not inhibited by PPARgamma antagonists, suggesting noncanonical or PPARgamma-independent mechanisms. In addition, PPARgamma antagonists, such as T0070907 and GW9662, have exhibited antiproliferative effects on a broad range of hematopoietic and epithelial cell lines, usually with greater potency than agonists. Also, additive antiproliferative effects of combinations of agonist plus antagonist drugs were observed. Finally, there are preclinical in vivo data showing that antagonist compounds can be administered safely, with favorable metabolic effects as well as antitumor effects. Since PPARgamma antagonists represent a new drug class that holds promise as a broadly applicable therapeutic approach for cancer treatment, it is the subject of this review.

  8. Potential of Peroxisome Proliferator-Activated Receptor Gamma Antagonist Compounds as Therapeutic Agents for a Wide Range of Cancer Types

    PubMed Central

    Burton, Jack D.; Goldenberg, David M.; Blumenthal, Rosalyn D.

    2008-01-01

    PPARγ is a therapeutic target that has been exploited for treatment of type II diabetes mellitus (T2DM) with agonist drugs. Since PPARγ is expressed by many hematopoietic, mesodermal and epithelial cancers, agonist drugs were tested and shown to have both preclinical and clinical anticancer activities. While preclinical activity has been observed in many cancer types, clinical activity has been observed only in pilot and phase II trials in liposarcoma and prostate cancer. Most studies address agonist compounds, with substantially fewer reports on anticancer effects of PPARγ antagonists. In cancer model systems, some effects of PPARγ agonists were not inhibited by PPARγ antagonists, suggesting noncanonical or PPARγ-independent mechanisms. In addition, PPARγ antagonists, such as T0070907 and GW9662, have exhibited antiproliferative effects on a broad range of hematopoietic and epithelial cell lines, usually with greater potency than agonists. Also, additive antiproliferative effects of combinations of agonist plus antagonist drugs were observed. Finally, there are preclinical in vivo data showing that antagonist compounds can be administered safely, with favorable metabolic effects as well as antitumor effects. Since PPARγ antagonists represent a new drug class that holds promise as a broadly applicable therapeutic approach for cancer treatment, it is the subject of this review. PMID:18779871

  9. Electropositive charge in alpha-defensin bactericidal activity: functional effects of Lys-for-Arg substitutions vary with the peptide primary structure.

    PubMed

    Llenado, R Alan; Weeks, Colby S; Cocco, Melanie J; Ouellette, André J

    2009-11-01

    Cationic amino acids contribute to alpha-defensin bactericidal activity. Curiously, although Arg and Lys have equivalent electropositive charges at neutral pH, alpha-defensins contain an average of nine Arg residues per Lys residue. To investigate the role of high alpha-defensin Arg content, all Arg residues in mouse Paneth cell alpha-defensin cryptdin 4 (Crp4) and rhesus myeloid alpha-defensin 4 (RMAD-4) were replaced with Lys to prepare (R/K)-Crp4 and (R/K)-RMAD-4, respectively. Lys-for-Arg replacements in Crp4 attenuated bactericidal activity and slowed the kinetics of Escherichia coli ML35 cell permeabilization, and (R/K)-Crp4 required longer exposure times to reduce E. coli cell survival. In marked contrast, Lys substitutions in RMAD-4 improved microbicidal activity against certain bacteria and permeabilized E. coli more effectively. Therefore, Arg-->Lys substitutions attenuated activity in Crp4 but not in RMAD-4, and the functional consequences of Arg-->Lys replacements in alpha-defensins are dependent on the peptide primary structure. In addition, the bactericidal effects of (R/K)-Crp4 and (R/K)-RMAD-4 were more sensitive to inhibition by NaCl than those of the native peptides, suggesting that the high Arg content of alpha-defensins may be under selection to confer superior microbicidal function under physiologic conditions.

  10. PHENOLIC CONTENT AND ANTIOXIDANT ACTIVITY OF SUPERCRITICAL CARBON DIOXIDE TREATED AND AIR-CLASSIFIED OAT BRAN CONCENTRATE MICROWAVE-IRRADIATED IN SOLVENTS AT VARYING TEMPERATURES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to health-beneficial beta-glucans, oats contain phenolic compounds (PC) and other antioxidant activity (AA). We investigated processing technologies to produce oat ingredients with concentrated levels of PC and AA. Oat bran concentrate (OBC) had lipids removed by supercritical carbon d...

  11. Genome-wide identification of genes involved in growth and fermentation activity at low temperature in Saccharomyces cerevisiae.

    PubMed

    Salvadó, Zoel; Ramos-Alonso, Lucía; Tronchoni, Jordi; Penacho, Vanessa; García-Ríos, Estéfani; Morales, Pilar; Gonzalez, Ramon; Guillamón, José Manuel

    2016-11-07

    Fermentation at low temperatures is one of the most popular current winemaking practices because of its reported positive impact on the aromatic profile of wines. However, low temperature is an additional hurdle to develop Saccharomyces cerevisiae wine yeasts, which are already stressed by high osmotic pressure, low pH and poor availability of nitrogen sources in grape must. Understanding the mechanisms of adaptation of S. cerevisiae to fermentation at low temperature would help to design strategies for process management, and to select and improve wine yeast strains specifically adapted to this winemaking practice. The problem has been addressed by several approaches in recent years, including transcriptomic and other high-throughput strategies. In this work we used a genome-wide screening of S. cerevisiae diploid mutant strain collections to identify genes that potentially contribute to adaptation to low temperature fermentation conditions. Candidate genes, impaired for growth at low temperatures (12°C and 18°C), but not at a permissive temperature (28°C), were deleted in an industrial homozygous genetic background, wine yeast strain FX10, in both heterozygosis and homozygosis. Some candidate genes were required for growth at low temperatures only in the laboratory yeast genetic background, but not in FX10 (namely the genes involved in aromatic amino acid biosynthesis). Other genes related to ribosome biosynthesis (SNU66 and PAP2) were required for low-temperature fermentation of synthetic must (SM) in the industrial genetic background. This result coincides with our previous findings about translation efficiency with the fitness of different wine yeast strains at low temperature.

  12. Local treatment of vaginal infections of varying etiology with dequalinium chloride or povidone iodine. A randomised, double-blind, active-controlled, multicentric clinical study.

    PubMed

    Petersen, Eiko E; Weissenbacher, Ernst R; Hengst, Peter; Spitzbart, Heinz; Weise, Wolfgang; Wolff, Friedrich; Dreher, Ekkehard; Ernst, Uwe; Della Casa, Vera; Pohlig, Gabriele; Graf, Federico; Kaiser, R Renato

    2002-01-01

    This randomised, double-blind, multicentric clinical study compared the efficacy and tolerability of the two vaginal antiseptics, 10 mg dequalinium chloride (CAS 522-51-0, Fluomycin N) and 200 mg povidone iodine (CAS 25655-41-8), in a parallel-group design. A total of 180 patients with vaginal infections of varying etiology participated in this study (bacterial vaginosis, fluor vaginalis, vulvo-vaginal candidiasis, trichomoniasis). Patients were randomly allocated to one of the two treatment groups and were treated once per day for 6 days. Control examinations took place 5 to 7 days after the end of treatment, and 3 to 4 weeks after the first control examination. The total symptoms score, a summary score for the clinical symptoms, discharge, burning, pruritus, redness of vulva/vagina, was defined as primary efficacy parameter. The treatments at the first control examination were compared in the full analysis set using the Wilcoxon-Mann-Whitney U-test, 2-sided, thereby proving equivalence of both treatments at the 5% level. Both treatments strongly improved the symptoms of vaginal infections both on short-term and long-term follow-up. Descriptive analysis of the secondary parameters, vaginal pH, degree of purity of the vaginal flora, and number of lactobacilli in the wet mounts, supported the comparable efficacy of both therapies to restore the vaginal milieu. Analysis of the diagnostic subgroups indicated that irrespective of the diagnosis, both treatments improved the efficacy criteria as observed for the entire population. The global assessment of the therapeutic efficacy by investigators and patients supported the results of the efficacy analysis with good to very good ratings in 70-90% of the cases. A good tolerability of both preparations was observed in this study with a low number of adverse events in the test group (5.8%).

  13. Deciphering the mechanism behind the varied binding activities of COXIBs through Molecular Dynamic Simulations, MM-PBSA binding energy calculations and per-residue energy decomposition studies.

    PubMed

    Chaudhary, Neha; Aparoy, Polamarasetty

    2017-03-01

    COX-2 is a well-known drug target in inflammatory disorders. COX-1/COX-2 selectivity of NSAIDs is crucial in assessing the gastrointestinal side effects associated with COX-1 inhibition. Celecoxib, rofecoxib, and valdecoxib are well-known specific COX-2 inhibiting drugs. Recently, polmacoxib, a COX-2/CA-II dual inhibitor has been approved by the Korean FDA. These COXIBs have similar structure with diverse activity range. Present study focuses on unraveling the mechanism behind the 10-fold difference in the activities of these sulfonamide-containing COXIBs. In order to obtain insights into their binding with COX-2 at molecular level, molecular dynamics simulations studies, and MM-PBSA approaches were employed. Further, per-residue decomposition of these energies led to the identification of crucial amino acids and interactions contributing to the differential binding of COXIBs. The results clearly indicated that Leu338, Ser339, Arg499, Ile503, Phe504, Val509, and Ser516 (Leu352, Ser353, Arg513, Ile517, Phe518, Val523, and Ser530 in PGHS-1 numbering) were imperative in determining the activity of these COXIBs. The binding energies and energy contribution of various residues were similar in all the three simulations. The results suggest that hydrogen bond interaction between the hydroxyl group of Ser516 and five-membered ring of diarylheterocycles augments the affinity in COXIBs. The SAR of the inhibitors studied and the per-residue energy decomposition values suggested the importance of Ser516. Additionally, the positive binding energy obtained with Arg106 explains the binding of COXIBs in hydrophobic channel deep in the COX-2 active site. The findings of the present work would aid in the development of potent COX-2 inhibitors.

  14. Chip, a widely expressed chromosomal protein required for segmentation and activity of a remote wing margin enhancer in Drosophila

    PubMed Central

    Morcillo, Patrick; Rosen, Christina; Baylies, Mary K.; Dorsett, Dale

    1997-01-01

    The mechanisms allowing remote enhancers to regulate promoters several kilobase pairs away are unknown but are blocked by the Drosophila suppressor of Hairy-wing protein (Suhw) that binds to gypsy retrovirus insertions between enhancers and promoters. Suhw bound to a gypsy insertion in the cut gene also appears to act interchromosomally to antagonize enhancer–promoter interactions on the homologous chromosome when activity of the Chip gene is reduced. This implicates Chip in enhancer–promoter communication. We cloned Chip and find that it encodes a homolog of the recently discovered mouse Nli/Ldb1/Clim-2 and Xenopus Xldb1 proteins that bind nuclear LIM domain proteins. Chip protein interacts with the LIM domains in the Apterous homeodomain protein, and Chip interacts genetically with apterous, showing that these interactions are important for Apterous function in vivo. Importantly, Chip also appears to have broad functions beyond interactions with LIM domain proteins. Chip is present in all nuclei examined and at numerous sites along the salivary gland polytene chromosomes. Embryos without Chip activity lack segments and show abnormal gap and pair–rule gene expression, although no LIM domain proteins are known to regulate segmentation. We conclude that Chip is a ubiquitous chromosomal factor required for normal expression of diverse genes at many stages of development. We suggest that Chip cooperates with different LIM domain proteins and other factors to structurally support remote enhancer–promoter interactions. PMID:9334334

  15. Vip3A, a novel Bacillus thuringiensis vegetative insecticidal protein with a wide spectrum of activities against lepidopteran insects.

    PubMed

    Estruch, J J; Warren, G W; Mullins, M A; Nye, G J; Craig, J A; Koziel, M G

    1996-05-28

    A novel vegetative insecticidal gene, vip3A(a), whose gene product shows activity against lepidopteran insect larvae including black cutworm (Agrotis ipsilon), fall armyworm (Spodoptera frugiperda), beet armyworm (Spodoptera exigua), tobacco budworm (Heliothis virescens), and corn earworm (Helicoverpa zea) has been isolated from Bacillus thuringiensis strain AB88. VIP3-insecticidal gene homologues have been detected in approximately 15% of Bacillus strains analyzed. The sequence of the vip3A(b) gene, a homologue of vip3A(a) isolated from B. thuringiensis strain AB424 is also reported. Vip3A(a) and (b) proteins confer upon Escherichia coli insecticidal activity against the lepidopteran insect larvae mentioned above. The sequence of the gene predicts a 791-amino acid (88.5 kDa) protein that contains no homology with known proteins. Vip3A insecticidal proteins are secreted without N-terminal processing. Unlike the B. thuringiensis 5-endotoxins, whose expression is restricted to sporulation, Vip3A insecticidal proteins are expressed in the vegetative stage of growth starting at mid-log phase as well as during sporulation. Vip3A represents a novel class of proteins insecticidal to lepidopteran insect larvae.

  16. Genome-wide co-localization of active EGFR and downstream ERK pathway kinases mirrors mitogen-inducible RNA polymerase 2 genomic occupancy

    PubMed Central

    Mikula, M.; Skrzypczak, M.; Goryca, K.; Paczkowska, K.; Ledwon, J.K.; Statkiewicz, M.; Kulecka, M.; Grzelak, M.; Dabrowska, M.; Kuklinska, U.; Karczmarski, J.; Rumienczyk, I.; Jastrzebski, K.; Miaczynska, M.; Ginalski, K.; Bomsztyk, K.; Ostrowski, J.

    2016-01-01

    Genome-wide mechanisms that coordinate expression of subsets of functionally related genes are largely unknown. Recent studies show that receptor tyrosine kinases and components of signal transduction cascades including the extracellular signal-regulated protein kinase (ERK), once thought to act predominantly in the vicinity of plasma membrane and in the cytoplasm, can be recruited to chromatin encompassing transcribed genes. Genome-wide distribution of these transducers and their relationship to transcribing RNA polymerase II (Pol2) could provide new insights about co-regulation of functionally related gene subsets. Chromatin immunoprecipitations (ChIP) followed by deep sequencing, ChIP-Seq, revealed that genome-wide binding of epidermal growth factor receptor, EGFR and ERK pathway components at EGF-responsive genes was highly correlated with characteristic mitogen-induced Pol2-profile. Endosomes play a role in intracellular trafficking of proteins including their nuclear import. Immunofluorescence revealed that EGF-activated EGFR, MEK1/2 and ERK1/2 co-localize on endosomes. Perturbation of endosome internalization process, through the depletion of AP2M1 protein, resulted in decreased number of the EGFR containing endosomes and inhibition of Pol2, EGFR/ERK recruitment to EGR1 gene. Thus, mitogen-induced co-recruitment of EGFR/ERK components to subsets of genes, a kinase module possibly pre-assembled on endosome to synchronize their nuclear import, could coordinate genome-wide transcriptional events to ensure effective cell proliferation. PMID:27587583

  17. Antifungal activity of wide band gap Thioglycolic acid capped ZnS:Mn semiconductor nanoparticles against some pathogenic fungi.

    PubMed

    Ibrahim, Isam M; Ali, Iftikhar M; Dheeb, Batol Imran; Abas, Qayes A; Asmeit Ramizy; Eisa, M H; Aljameel, A I

    2017-04-01

    The manganese doped zinc sulfide nanoparticles were synthesized by simple aqueous chemical reaction of manganese chloride, zinc acetate and thioacitamide in aqueous solution. Thioglycolic acid is used as capping agent for controlling the nanoparticle size. The main advantage of the ZnS:Mn nanoparticles of diameter ~2.73nm is that the sample is prepared by using non-toxic precursors in a cost effective and eco-friendly way. The structural, morphological and chemical composition of the nanoparticles have been investigated by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) with energy dispersion spectroscopy (EDS) and Fourier transform infrared (FTIR) spectroscopy. The nanosize of the prepared nanoparticles was elucidated by Scanning Electron Microscopy (SEM). FTIR result ensures that Thioglycolic acid is well bonded on the surface of ZnS:Mn NPs. The antifungal effects of Thioglycolic acid capped ZnS:Mn nanoparticles exhibited a potent antifungal activity against tested fungal strains, so deserving further investigation for clinical applications. The antifungal property of manganese doped zinc sulphide nanoparticles is attributed to the generation of reactive oxygen species due to the interaction of nanoparticles with water. Additionally, the presence of Zn and S in the zone of inhibition area leads to perturbation of fungi cell membranes resulting in growth inhibition.

  18. Genome-Wide Identification and Expression Analysis of the Mitogen-Activated Protein Kinase Gene Family in Cassava

    PubMed Central

    Yan, Yan; Wang, Lianzhe; Ding, Zehong; Tie, Weiwei; Ding, Xupo; Zeng, Changying; Wei, Yunxie; Zhao, Hongliang; Peng, Ming; Hu, Wei

    2016-01-01

    Mitogen-activated protein kinases (MAPKs) play central roles in plant developmental processes, hormone signaling transduction, and responses to abiotic stress. However, no data are currently available about the MAPK family in cassava, an important tropical crop. Herein, 21 MeMAPK genes were identified from cassava. Phylogenetic analysis indicated that MeMAPKs could be classified into four subfamilies. Gene structure analysis demonstrated that the number of introns in MeMAPK genes ranged from 1 to 10, suggesting large variation among cassava MAPK genes. Conserved motif analysis indicated that all MeMAPKs had typical protein kinase domains. Transcriptomic analysis suggested that MeMAPK genes showed differential expression patterns in distinct tissues and in response to drought stress between wild subspecies and cultivated varieties. Interaction networks and co-expression analyses revealed that crucial pathways controlled by MeMAPK networks may be involved in the differential response to drought stress in different accessions of cassava. Expression of nine selected MAPK genes showed that these genes could comprehensively respond to osmotic, salt, cold, oxidative stressors, and abscisic acid (ABA) signaling. These findings yield new insights into the transcriptional control of MAPK gene expression, provide an improved understanding of abiotic stress responses and signaling transduction in cassava, and lead to potential applications in the genetic improvement of cassava cultivars. PMID:27625666

  19. Requirements for intercistronic distance and level of eukaryotic initiation factor 2 activity in reinitiation on GCN4 mRNA vary with the downstream cistron.

    PubMed Central

    Grant, C M; Miller, P F; Hinnebusch, A G

    1994-01-01

    Translational control of the GCN4 gene in response to amino acid availability is mediated by four short open reading frames in the GCN4 mRNA leader (uORFs) and by phosphorylation of eukaryotic initiation factor 2 (eIF-2). We have proposed that reducing eIF-2 activity by phosphorylation of its alpha subunit or by a mutation in the eIF-2 recycling factor eIF-2B allows ribosomes which have translated the 5'-proximal uORF1 to bypass uORF2 to uORF4 and reinitiate at GCN4 instead. In this report, we present two lines of evidence that all ribosomes which synthesize GCN4 have previously translated uORF1, resumed scanning, and reinitiated at the GCN4 start site. First, GCN4 expression was abolished when uORF1 was elongated to make it overlap the beginning of the GCN4 coding region. Second, GCN4 expression was reduced as uORF1 was moved progressively closer to GCN4, decreasing to only 5% of the level seen in the absence of all uORFs when only 32 nucleotides separated uORF1 from GCN4. We additionally found that inserting small synthetic uORFs between uORF4 and GCN4 inhibited GCN4 expression under derepressing conditions, confirming the idea that reinitiation at GCN4 under conditions of diminished eIF-2 activity is proportional to the distance of the reinitiation site downstream from uORF1. While uORF4 and GCN4 appear to be equally effective at capturing ribosomes scanning downstream from the 5' cap of mRNA, these two ORFs differ greatly in their ability to capture reinitiating ribosomes scanning from uORF1. When the active form of eIF-2 is present at high levels, reinitiation appears to be much more efficient at uORF4 than at GCN4 when each is located very close to uORF1. Under conditions of reduced recycling of eIF-2, reinitiation at uORF4 is substantially suppressed, which allows ribosomes to reach the GCN4 start site; in contrast, reinitiation at GCN4 in constructs lacking uORF4 is unaffected by decreasing the level of eIF-2 activity. This last finding raises the

  20. Ovarian cycle activity varies with respect to age and social status in free-ranging elephants in Addo Elephant National Park, South Africa.

    PubMed

    Freeman, Elizabeth W; Meyer, Jordana M; Putman, Sarah B; Schulte, Bruce A; Brown, Janine L

    2013-01-01

    Free-ranging African elephants live in a fission-fusion society, at the centre of which is the matriarch. Matriarchs are generally older females that guide their families to resources and co-ordinate group defense. While much is known about elephant society, knowledge is generally lacking about how age affects the physiology of wild elephants. Investigation of the ovarian activity of free-ranging elephants could provide insight into the reproductive ageing process, with implications for population management. Faecal samples were collected from 46 individuals ranging in age from 14 to 60 years for a 2-year period, and progestagen metabolite analyses were used to examine relationships between social status, age, season, and ovarian activity in female elephants in Addo Elephant National Park, South Africa. Social status was the strongest predictor of faecal progestagen metabolite concentrations in non-pregnant elephants, with grand matriarchs (n = 6) having the lowest values compared with matriarchs (n = 21) and non-matriarch females (n = 19). Likewise, social status and age were the strongest predictors of faecal progestagen metabolite concentrations in pregnant elephants (n = 27). The number of years since a non-pregnant female gave birth to her last calf (post-partum duration) was longer for older females with a higher social status, as well as during the dry season. Our results indicate that social standing and age of elephants are related to reproductive function, and that older females exhibit reductions in ovarian capacity. These results expand our understanding of reproduction and fertility throughout an elephant's lifespan, and the factors that impact gonadal function in free-ranging females. Given that possible over-abundance of elephants in areas such as Addo Elephant National Park is fuelling the debate over how best to manage these populations, knowledge about the reproductive potential of high-ranking females can provide managers with

  1. Fathoms Below: Propagation of Deep Water-driven Fractures and Implications for Surface Expression and Temporally-varying Activity at Europa

    NASA Astrophysics Data System (ADS)

    Walker, C. C.; Craft, K.; Schmidt, B. E.

    2015-12-01

    The fracture and failure of Europa's icy shell are not only observable scars of variable stress and activity throughout its evolution, they also serve key as mechanisms in the interaction of surface and subsurface material, and thus crucial aspects of the study of crustal overturn and ice shell habitability. Galileo images, our best and only reasonable-resolution views of Europa until the Europa Multiple Flyby Mission arrives in the coming decades, illustrates a single snapshot in time in Europa's history from which we deduce many temporally-based hypotheses. One of those hypotheses, which we investigate here, is that sub-surface water-both in the form of Great Lake-sized perched water pockets in the near-surface and the larger global ocean below-drives the deformation, fracture, and failure of the surface. Using Galileo's snapshot in time, we use a 2D/3D hydraulic fracturing model to investigate the propagation of vertical fractures upward into the ice shell, motion of water within and between fractures, and the subsequent break-up of ice over shallow water, forming the chaos regions and other smaller surface features. We will present results from a cohesive fragmentation model to determine the time over which chaos formation occurs, and use a fracking model to determine the time interval required to allow water to escape from basal fractures in the ice shell. In determining the style, energy, and timescale of these processes, we constrain temporal variability in observable activity and topography at the surface. Finally, we compare these results to similar settings on Earth-Antarctica-where we have much higher resolution imagery and observations to better understand how sub-surface water can affect ice surface morphology, which most certainly have implications for future flyby and surface lander exploration.

  2. Antimicrobial activity of oregano oil against antibiotic-resistant Salmonella enterica on organic leafy greens at varying exposure times and storage temperatures.

    PubMed

    Moore-Neibel, Katherine; Gerber, Colin; Patel, Jitendra; Friedman, Mendel; Jaroni, Divya; Ravishankar, Sadhana

    2013-05-01

    The objective of this study was to evaluate the effectiveness of oregano oil on four organic leafy greens (Iceberg and Romaine lettuces and mature and baby spinaches) inoculated with Salmonella Newport as a function of treatment exposure times as well as storage temperatures. Leaf samples were washed, dip inoculated with S. Newport (6-log CFU/ml) and dried. Oregano oil was prepared at 0.1, 0.3, and 0.5% concentrations in sterile phosphate buffered saline (PBS). Inoculated leaves were immersed in the treatment solution for 1 or 2 min, and individually incubated at 4 or 8 °C. Samples were taken at day 0, 1, and 3 for enumeration of survivors. The results showed that oregano oil was effective against S. Newport at all concentrations. S. Newport showed reductions from the PBS control of 0.7-4.8 log CFU/g (Romaine lettuce), 0.8-4.8 log CFU/g (Iceberg lettuce), 0.8-4.9 log CFU/g (mature spinach), and 0.5-4.7 log CFU/g (baby spinach), respectively. The antibacterial activity also increased with exposure time. Leaf samples treated for 2 min generally showed greater reductions (by 1.4-3.2 log CFU/g), than those samples treated for 1 min; however, there was minimal difference in antimicrobial activity among samples stored under refrigeration and abuse temperatures. This study demonstrates the potential of oregano oil to inactivate S. Newport on organic leafy greens.

  3. Cosmology with varying constants.

    PubMed

    Martins, Carlos J A P

    2002-12-15

    The idea of possible time or space variations of the 'fundamental' constants of nature, although not new, is only now beginning to be actively considered by large numbers of researchers in the particle physics, cosmology and astrophysics communities. This revival is mostly due to the claims of possible detection of such variations, in various different contexts and by several groups. I present the current theoretical motivations and expectations for such variations, review the current observational status and discuss the impact of a possible confirmation of these results in our views of cosmology and physics as a whole.

  4. Analysis and Design of Time-Varying Filter Banks

    NASA Astrophysics Data System (ADS)

    Sodagar, Iraj

    Analysis-synthesis filter banks have been studied extensively and a wide range of theoretical problems have been subsequently addressed. However, almost all the research activity has been concentrated on time-invariant filter banks whose components are fixed and do not change in time. The objective of this thesis is to develop analysis and design techniques for time-varying FIR analysis-synthesis filter banks that are perfect reconstructing (PR). In such systems, the analysis and/or synthesis filters, the down-up sampling rates, or even the number of bands can change in time. The underlying idea is that by adapting the basis functions of the filter bank transform to the signal properties, one can represent the relevant information of the signal more efficiently. For analysis purposes, we derive the time-varying impulse response of the filter bank in terms of the analysis and synthesis filter coefficients. We are able to represent this impulse response in terms of the product of the analysis and synthesis matrix transforms. Our approach to the PR time-varying filter bank design is to change the analysis -synthesis filter bank among a set of time-invariant filter banks. The analysis filter banks are switched instantaneously. To eliminate the distortion during switching, a new time-varying synthesis section is designed for each transition. Three design techniques are developed for the time-varying filter bank design. The first technique uses the least squares synthesis filters. This method improves the reconstruction quality significantly, but does not usually achieve the perfect reconstruction. Using the second technique, one can design PR time-varying systems by redesigning the analysis filters. The drawback is that this method requires numerical optimizations. The third technique introduces a new structure for exactly reconstructing time-varying filter banks. This structure consists of the conventional filter bank followed by a time-varying post filter. The post

  5. Double-stranded RNA-activated protein kinase PKR of fishes and amphibians: Varying the number of double-stranded RNA binding domains and lineage-specific duplications

    PubMed Central

    Rothenburg, Stefan; Deigendesch, Nikolaus; Dey, Madhusudan; Dever, Thomas E; Tazi, Loubna

    2008-01-01

    Background Double-stranded (ds) RNA, generated during viral infection, binds and activates the mammalian anti-viral protein kinase PKR, which phosphorylates the translation initiation factor eIF2α leading to the general inhibition of protein synthesis. Although PKR-like activity has been described in fish cells, the responsible enzymes eluded molecular characterization until the recent discovery of goldfish and zebrafish PKZ, which contain Z-DNA-binding domains instead of dsRNA-binding domains (dsRBDs). Fish and amphibian PKR genes have not been described so far. Results Here we report the cloning and identification of 13 PKR genes from 8 teleost fish and amphibian species, including zebrafish, demonstrating the coexistence of PKR and PKZ in this latter species. Analyses of their genomic organization revealed up to three tandemly arrayed PKR genes, which are arranged in head-to-tail orientation. At least five duplications occurred independently in fish and amphibian lineages. Phylogenetic analyses reveal that the kinase domains of fish PKR genes are more closely related to those of fish PKZ than to the PKR kinase domains of other vertebrate species. The duplication leading to fish PKR and PKZ genes occurred early during teleost fish evolution after the divergence of the tetrapod lineage. While two dsRBDs are found in mammalian and amphibian PKR, one, two or three dsRBDs are present in fish PKR. In zebrafish, both PKR and PKZ were strongly upregulated after immunostimulation with some tissue-specific expression differences. Using genetic and biochemical assays we demonstrate that both zebrafish PKR and PKZ can phosphorylate eIF2α in yeast. Conclusion Considering the important role for PKR in host defense against viruses, the independent duplication and fixation of PKR genes in different lineages probably provided selective advantages by leading to the recognition of an extended spectrum of viral nucleic acid structures, including both dsRNA and Z-DNA/RNA, and

  6. Agreement Between pQCT- and DXA-Derived Indices of Bone Geometry, Density, and Theoretical Strength in Females of Varying Age, Maturity, and Physical Activity

    PubMed Central

    Dowthwaite, Jodi Noelle; Flowers, Portia PE; Scerpella, Tamara Ann

    2011-01-01

    Measurement of bone mass, geometry, density, and strength are critical in bone research and clinical studies. For peripheral quantitative computed tomography (pQCT), single and repeated measurements are particularly adversely affected by movement and positional variation. Dual-energy X-ray absorptiometry (DXA)–derived indices may alleviate these problems and provide useful alternative assessments. To evaluate this hypothesis, distal radius DXA and pQCT indices were compared in 101 healthy females aged 8.0 to 22.8 years (prepuberty to adulthood), reflecting a broad range of body sizes, physical maturity, and activity exposures. At the diaphysis, correlations were ρ =+0.74 to +0.98, with strong intermethod agreement for most indices. At the metaphysis, correlations were ρ =+0.64 to +0.97; intermethod agreement improved with modifications to the simplified geometric formulas more closely reflecting metaphyseal bone geometry. Further improvements may be possible because skeletal size and maturity-related biases in agreement were detected. Overall, DXA-derived indices may provide a useful assessment of bone geometry, density, and theoretical strength contingent on appropriate consideration of their limitations. PMID:21611973

  7. Exposure to Solute Stress Affects Genome-Wide Expression but Not the Polycyclic Aromatic Hydrocarbon-Degrading Activity of Sphingomonas sp. Strain LH128 in Biofilms

    PubMed Central

    Fida, Tekle Tafese; Breugelmans, Philip; Lavigne, Rob; Coronado, Edith; Johnson, David R.; van der Meer, Jan Roelof; Mayer, Antonia P.; Heipieper, Hermann J.; Hofkens, Johan

    2012-01-01

    Members of the genus Sphingomonas are important catalysts for removal of polycyclic aromatic hydrocarbons (PAHs) in soil, but their activity can be affected by various stress factors. This study examines the physiological and genome-wide transcription response of the phenanthrene-degrading Sphingomonas sp. strain LH128 in biofilms to solute stress (invoked by 450 mM NaCl solution), either as an acute (4-h) or a chronic (3-day) exposure. The degree of membrane fatty acid saturation was increased as a response to chronic stress. Oxygen consumption in the biofilms and phenanthrene mineralization activities of biofilm cells were, however, not significantly affected after imposing either acute or chronic stress. This finding was in agreement with the transcriptomic data, since genes involved in PAH degradation were not differentially expressed in stressed conditions compared to nonstressed conditions. The transcriptomic data suggest that LH128 adapts to NaCl stress by (i) increasing the expression of genes coping with osmolytic and ionic stress such as biosynthesis of compatible solutes and regulation of ion homeostasis, (ii) increasing the expression of genes involved in general stress response, (iii) changing the expression of general and specific regulatory functions, and (iv) decreasing the expression of protein synthesis such as proteins involved in motility. Differences in gene expression between cells under acute and chronic stress suggest that LH128 goes through changes in genome-wide expression to fully adapt to NaCl stress, without significantly changing phenanthrene degrading activity. PMID:23001650

  8. EVIDENCE OF A WARM ABSORBER THAT VARIES WITH QUASI-PERIODIC OSCILLATION PHASE IN THE ACTIVE GALACTIC NUCLEUS RE J1034+396

    SciTech Connect

    Maitra, Dipankar; Miller, Jon M. E-mail: jonmm@umich.ed

    2010-07-20

    A recent observation of the nearby (z = 0.042) narrow-line Seyfert 1 galaxy RE J1034+396 on 2007 May 31 showed strong quasi-periodic oscillations (QPOs) in the 0.3-10 keV X-ray flux. We present phase-resolved spectroscopy of this observation, using data obtained by the EPIC PN detector on board XMM-Newton. The 'low' phase spectrum, associated with the troughs in the light curve, shows (at >4{sigma} confidence level) an absorption edge at 0.86 {+-} 0.05 keV with an absorption depth of 0.3 {+-} 0.1. Ionized oxygen edges are hallmarks of X-ray warm absorbers in Seyfert active galactic nuclei; the observed edge is consistent with H-like O VIII and implies a column density of N{sub OVIII} {approx} 3 x 10{sup 18} cm{sup -2}. The edge is not seen in the 'high' phase spectrum associated with the crests in the light curve, suggesting the presence of a warm absorber in the immediate vicinity of the supermassive black hole that periodically obscures the continuum emission. If the QPO arises due to Keplerian orbital motion around the central black hole, the periodic appearance of the O VIII edge would imply a radius of {approx}9.4(M/[4x10{sup 6}M{sub sun}]){sup -2/3}(P/[1 hr]){sup 2/3} r{sub g} for the size of the warm absorber.

  9. A Genome-wide CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) Screen Identifies NEK7 as an Essential Component of NLRP3 Inflammasome Activation.

    PubMed

    Schmid-Burgk, Jonathan L; Chauhan, Dhruv; Schmidt, Tobias; Ebert, Thomas S; Reinhardt, Julia; Endl, Elmar; Hornung, Veit

    2016-01-01

    Inflammasomes are high molecular weight protein complexes that assemble in the cytosol upon pathogen encounter. This results in caspase-1-dependent pro-inflammatory cytokine maturation, as well as a special type of cell death, known as pyroptosis. The Nlrp3 inflammasome plays a pivotal role in pathogen defense, but at the same time, its activity has also been implicated in many common sterile inflammatory conditions. To this effect, several studies have identified Nlrp3 inflammasome engagement in a number of common human diseases such as atherosclerosis, type 2 diabetes, Alzheimer disease, or gout. Although it has been shown that known Nlrp3 stimuli converge on potassium ion efflux upstream of Nlrp3 activation, the exact molecular mechanism of Nlrp3 activation remains elusive. Here, we describe a genome-wide CRISPR/Cas9 screen in immortalized mouse macrophages aiming at the unbiased identification of gene products involved in Nlrp3 inflammasome activation. We employed a FACS-based screen for Nlrp3-dependent cell death, using the ionophoric compound nigericin as a potassium efflux-inducing stimulus. Using a genome-wide guide RNA (gRNA) library, we found that targeting Nek7 rescued macrophages from nigericin-induced lethality. Subsequent studies revealed that murine macrophages deficient in Nek7 displayed a largely blunted Nlrp3 inflammasome response, whereas Aim2-mediated inflammasome activation proved to be fully intact. Although the mechanism of Nek7 functioning upstream of Nlrp3 yet remains elusive, these studies provide a first genetic handle of a component that specifically functions upstream of Nlrp3.

  10. Genome-Wide Identification of Mitogen-Activated Protein Kinase Gene Family across Fungal Lineage Shows Presence of Novel and Diverse Activation Loop Motifs

    PubMed Central

    Mohanta, Tapan Kumar; Mohanta, Nibedita; Parida, Pratap; Panda, Sujogya Kumar; Ponpandian, Lakshmi Narayanan; Bae, Hanhong

    2016-01-01

    The mitogen-activated protein kinase (MAPK) is characterized by the presence of the T-E-Y, T-D-Y, and T-G-Y motifs in its activation loop region and plays a significant role in regulating diverse cellular responses in eukaryotic organisms. Availability of large-scale genome data in the fungal kingdom encouraged us to identify and analyse the fungal MAPK gene family consisting of 173 fungal species. The analysis of the MAPK gene family resulted in the discovery of several novel activation loop motifs (T-T-Y, T-I-Y, T-N-Y, T-H-Y, T-S-Y, K-G-Y, T-Q-Y, S-E-Y and S-D-Y) in fungal MAPKs. The phylogenetic analysis suggests that fungal MAPKs are non-polymorphic, had evolved from their common ancestors around 1500 million years ago, and are distantly related to plant MAPKs. We are the first to report the presence of nine novel activation loop motifs in fungal MAPKs. The specificity of the activation loop motif plays a significant role in controlling different growth and stress related pathways in fungi. Hence, the presences of these nine novel activation loop motifs in fungi are of special interest. PMID:26918378

  11. Genome-wide analysis of DNA methylation and gene expression patterns in purified, uncultured human liver cells and activated hepatic stellate cells

    PubMed Central

    Reiner, Andrew H.; Coll, Mar; Verhulst, Stefaan; Mannaerts, Inge; Øie, Cristina I.; Smedsrød, Bård; Najimi, Mustapha; Sokal, Etienne; Luttun, Aernout; Sancho-Bru, Pau; Collas, Philippe; van Grunsven, Leo A.

    2015-01-01

    Background & Aims Liver fibrogenesis – scarring of the liver that can lead to cirrhosis and liver cancer – is characterized by hepatocyte impairment, capillarization of liver sinusoidal endothelial cells (LSECs) and hepatic stellate cell (HSC) activation. To date, the molecular determinants of a healthy human liver cell phenotype remain largely uncharacterized. Here, we assess the transcriptome and the genome-wide promoter methylome specific for purified, non-cultured human hepatocytes, LSECs and HSCs, and investigate the nature of epigenetic changes accompanying transcriptional changes associated with activation of HSCs. Material and methods Gene expression profile and promoter methylome of purified, uncultured human liver cells and culture-activated HSCs were respectively determined using Affymetrix HG-U219 genechips and by methylated DNA immunoprecipitation coupled to promoter array hybridization. Histone modification patterns were assessed at the single-gene level by chromatin immunoprecipitation and quantitative PCR. Results We unveil a DNA-methylation-based epigenetic relationship between hepatocytes, LSECs and HSCs despite their distinct ontogeny. We show that liver cell type-specific DNA methylation targets early developmental and differentiation-associated functions. Integrative analysis of promoter methylome and transcriptome reveals partial concordance between DNA methylation and transcriptional changes associated with human HSC activation. Further, we identify concordant histone methylation and acetylation changes in the promoter and putative novel enhancer elements of genes involved in liver fibrosis. Conclusions Our study provides the first epigenetic blueprint of three distinct freshly isolated, human hepatic cell types and of epigenetic changes elicited upon HSC activation. PMID:26353929

  12. Active optics and the axisymmetric case: MINITRUST wide-field three-reflection telescopes with mirrors aspherized from tulip and vase forms

    NASA Astrophysics Data System (ADS)

    Lemaitre, Gerard R.; Montiel, Pierre; Joulie, Patrice; Dohlen, Kjetil; Lanzoni, Patrick

    2004-09-01

    Wide-field astronomy requires larger size telescopes. Compared to the catadioptric Schmidt, the optical properties of a three mirror telescope provides significant advantages. (1) The flat field design is anastigmatic at any wavelength, (2) the system is extremely compact -- four times shorter than a Schmidt -- and, (3) compared to a Schmidt with refractive corrector -- requiring the polishing of three optical surfaces --, the presently proposed Modified-Rumsey design uses all of eight available free parameters of a flat fielded anastigmatic three mirror telescope for mirrors generated by active optics methods. Compared to a Rumsey design, these parameters include the additional slope continuity condition at the primary-tertiary link for in-situ stressing and aspherization from a common sphere. Then, active optics allows the polishing of only two spherical surfaces: the combined primary-tertiary mirror and the secondary mirror. All mirrors are spheroids of the hyperboloid type. This compact system is of interest for space and ground-based astronomy and allows to built larger wide-field telescopes such as demonstrated by the design and construction of identical telescopes MINITRUST-1 and -2, f/5 - 2° FOV, consisting of an in-situ stressed double vase form primary-tertiary and of a stress polished tulip form secondary. Optical tests of these telescopes, showing diffraction limited images, are presented.

  13. Genome-wide specificity of DNA binding, gene regulation, and chromatin remodeling by TALE- and CRISPR/Cas9-based transcriptional activators.

    PubMed

    Polstein, Lauren R; Perez-Pinera, Pablo; Kocak, D Dewran; Vockley, Christopher M; Bledsoe, Peggy; Song, Lingyun; Safi, Alexias; Crawford, Gregory E; Reddy, Timothy E; Gersbach, Charles A

    2015-08-01

    Genome engineering technologies based on the CRISPR/Cas9 and TALE systems are enabling new approaches in science and biotechnology. However, the specificity of these tools in complex genomes and the role of chromatin structure in determining DNA binding are not well understood. We analyzed the genome-wide effects of TALE- and CRISPR-based transcriptional activators in human cells using ChIP-seq to assess DNA-binding specificity and RNA-seq to measure the specificity of perturbing the transcriptome. Additionally, DNase-seq was used to assess genome-wide chromatin remodeling that occurs as a result of their action. Our results show that these transcription factors are highly specific in both DNA binding and gene regulation and are able to open targeted regions of closed chromatin independent of gene activation. Collectively, these results underscore the potential for these technologies to make precise changes to gene expression for gene and cell therapies or fundamental studies of gene function.

  14. Genome-wide analysis of MEF2 transcriptional program reveals synaptic target genes and neuronal activity-dependent polyadenylation site selection

    PubMed Central

    Flavell, Steven W.; Kim, Tae-Kyung; Gray, Jesse M.; Harmin, David A.; Hemberg, Martin; Hong, Elizabeth J.; Markenscoff-Papadimitriou, Eirene; Bear, Daniel M.; Greenberg, Michael E.

    2009-01-01

    SUMMARY Although many transcription factors are known to control important aspects of neural development, the genome-wide programs that are directly regulated by these factors are not known. We have characterized the genetic program that is activated by MEF2, a key regulator of activity-dependent synapse development. These MEF2 target genes have diverse functions at synapses, revealing a broad role for MEF2 in synapse development. Several of the MEF2 targets are mutated in human neurological disorders including epilepsy and autism-spectrum disorders, suggesting that these disorders may be caused by disruption of an activity-dependent gene program that controls synapse development. Our analyses also reveal that neuronal activity promotes alternative polyadenylation site usage at many of the MEF2 target genes, leading to the production of truncated mRNAs that may have different functions than their full-length counterparts. Taken together, these analyses suggest that the ubiquitously expressed transcription factor MEF2 regulates an intricate transcriptional program in neurons that controls synapse development. PMID:19109909

  15. Genome-wide binding analysis of the transcription activator ideal plant architecture1 reveals a complex network regulating rice plant architecture.

    PubMed

    Lu, Zefu; Yu, Hong; Xiong, Guosheng; Wang, Jing; Jiao, Yongqing; Liu, Guifu; Jing, Yanhui; Meng, Xiangbing; Hu, Xingming; Qian, Qian; Fu, Xiangdong; Wang, Yonghong; Li, Jiayang

    2013-10-01

    Ideal plant architecture1 (IPA1) is critical in regulating rice (Oryza sativa) plant architecture and substantially enhances grain yield. To elucidate its molecular basis, we first confirmed IPA1 as a functional transcription activator and then identified 1067 and 2185 genes associated with IPA1 binding sites in shoot apices and young panicles, respectively, through chromatin immunoprecipitation sequencing assays. The Squamosa promoter binding protein-box direct binding core motif GTAC was highly enriched in IPA1 binding peaks; interestingly, a previously uncharacterized indirect binding motif TGGGCC/T was found to be significantly enriched through the interaction of IPA1 with proliferating cell nuclear antigen promoter binding factor1 or promoter binding factor2. Genome-wide expression profiling by RNA sequencing revealed IPA1 roles in diverse pathways. Moreover, our results demonstrated that IPA1 could directly bind to the promoter of rice teosinte branched1, a negative regulator of tiller bud outgrowth, to suppress rice tillering, and directly and positively regulate dense and erect panicle1, an important gene regulating panicle architecture, to influence plant height and panicle length. The elucidation of target genes of IPA1 genome-wide will contribute to understanding the molecular mechanisms underlying plant architecture and to facilitating the breeding of elite varieties with ideal plant architecture.

  16. Visible light photocatalytic H2-production activity of wide band gap ZnS nanoparticles based on the photosensitization of grapheme.

    PubMed

    Wang, Faze; Zheng, Maojun; Zhu, Changqing; Zhang, Bin; Chen, Wen; Ma, Li; Shen, Wenzhong

    2015-08-28

    Visible light photocatalytic H(2) production from water splitting is considered an attractive way to solve the increasing global energy crisis in modern life. In this study, a series of zinc sulfide nanoparticles and graphene (GR) sheet composites were synthesized by a two-step hydrothermal method, which used zinc chloride, sodium sulfide, and graphite oxide (GO) as the starting materials. The as-prepared ZnS-GR showed highly efficient visible light photocatalytic activity in hydrogen generation. The morphology and structure of the composites obtained by transmission electron microscope and x-ray diffraction exhibited a small crystallite size and a good interfacial contact between the ZnS nanoparticles and the two-dimensional (2D) GR sheet,which were beneficial for the photocatalysis. When the content of the GR in the catalyst was 0.1%, the ZG0.1 sample exhibited the highest H(2)-production rate of 7.42 μmol h(−1) g(−1), eight times more than the pure ZnS sample. This high visible-light photocatalytic H(2) production activity is attributed to the photosensitization of GR. Irradiated by visible light, the electrons photogenerated from GR transfer to the conduction band of ZnS to participate in the photocatalytic process. This study presents the visible-light photocatalytic activity of wide bandgap ZnS and its application in H(2) evolution.

  17. Genome-wide localization of Rrm3 and Pif1 DNA helicases at stalled active and inactive DNA replication forks of Saccharomyces cerevisiae

    PubMed Central

    Rossi, Silvia Emma; Carotenuto, Walter; Giannattasio, Michele

    2015-01-01

    The genome of the budding yeast Saccharomyces cerevisiae is sequenced and the location and dynamic of activation of DNA replication origins are known. G1 synchronized yeast cells can be released into S-phase in the presence of hydroxyurea (HU) (1), which slows down DNA replication and retains replication forks in proximity of DNA replication origins. In this condition, the Chromatin Immuno-Precipitation on chip (ChIP on chip) (2–4) of replisome components allows the precise localization of all active DNA replication forks. This analysis can be coupled with the ssDNA-BromodeoxyUridine (ssDNA-BrdU) Immuno-Precipitation on chip (ssDNA-BrdU IP on chip) technique (5–7), which detects the location of newly synthesized DNA. Comparison of binding and BrdU incorporation profiles allows to locate a factor of interest at DNA replication forks genome wide. We present datasets deposited in the gene expression omnibus (GEO) database under accession number GSE68214, which show how the DNA helicases Rrm3 and Pif1 (8) associate to active and inactive DNA replication forks. PMID:26981397

  18. ISEE 3 observations during the CDAW 8 intervals - Case studies of the distant geomagnetic tail covering a wide range of geomagnetic activity

    NASA Technical Reports Server (NTRS)

    Richardson, I. G.; Slavin, J. A.; Owen, C. J.; Cowley, S. W. H.; Galvin, A. B.; Sanderson, T. R.; Scholer, M.

    1989-01-01

    Observations made by the ISEE 3 spacecraft in the distant geomagnetic tail during the eight CDAW 8 intervals are discussed, along with their relation to concurrent geomagnetic activity. This extensive multiinstrument case study of distant tail data covers a wide range of geomagnetic conditions from extended intervals of magnetic quiet with isolated substorms to prolonged periods of intense disturbance. Plasmoids are observed in the distant tail following disturbance enhancements, the time of their appearance being generally consistent with disconnection from the near-earth region at the time of the enhancement. Their structure is entirely consistent with the neutral line model. However, not all enhancements in geomagnetic activity result in the observation of plasmoids. In particular, the CDAW 8 data suggest that, during extended intervals of strong activity, a continuous neutral line may reside in the near-earth tail and some disturbance enhancements may then relate to an increase in the reconnection rate at a preexisting neutral line, rather than to new neutral line and plasmoid formation.

  19. A successful virtual screening application: prediction of anticonvulsant activity in MES test of widely used pharmaceutical and food preservatives methylparaben and propylparaben

    NASA Astrophysics Data System (ADS)

    Talevi, Alan; Bellera, Carolina L.; Castro, Eduardo A.; Bruno-Blanch, Luis E.

    2007-09-01

    A discriminant function based on topological descriptors was derived from a training set composed by anticonvulsants of clinical use or in clinical phase of development and compounds with other therapeutic uses. This model was internally and externally validated and applied in the virtual screening of chemical compounds from the Merck Index 13th. Methylparaben (Nipagin), a preservative widely used in food, cosmetics and pharmaceutics, was signaled as active by the discriminant function and tested in mice in the Maximal Electroshock (MES) test (i.p. administration), according to the NIH Program for Anticonvulsant Drug Development. Based on the results of Methylparaben, Propylparaben (Nipasol), another preservative usually used in association with the former, was also tested. Both methyl and propylparaben were found active in mice at doses of 30, 100, and 300 mg/kg. The discovery of the anticonvulsant activities in the MES test of methylparaben and propylparaben might be useful for the development of new anticonvulsant medications, specially considering the well-known toxicological profile of these drugs.

  20. Visible light photocatalytic H2-production activity of wide band gap ZnS nanoparticles based on the photosensitization of graphene

    NASA Astrophysics Data System (ADS)

    Wang, Faze; Zheng, Maojun; Zhu, Changqing; Zhang, Bin; Chen, Wen; Ma, Li; Shen, Wenzhong

    2015-08-01

    Visible light photocatalytic H2 production from water splitting is considered an attractive way to solve the increasing global energy crisis in modern life. In this study, a series of zinc sulfide nanoparticles and graphene (GR) sheet composites were synthesized by a two-step hydrothermal method, which used zinc chloride, sodium sulfide, and graphite oxide (GO) as the starting materials. The as-prepared ZnS-GR showed highly efficient visible light photocatalytic activity in hydrogen generation. The morphology and structure of the composites obtained by transmission electron microscope and x-ray diffraction exhibited a small crystallite size and a good interfacial contact between the ZnS nanoparticles and the two-dimensional (2D) GR sheet, which were beneficial for the photocatalysis. When the content of the GR in the catalyst was 0.1%, the ZG0.1 sample exhibited the highest H2-production rate of 7.42 μmol h-1 g-1, eight times more than the pure ZnS sample. This high visible-light photocatalytic H2 production activity is attributed to the photosensitization of GR. Irradiated by visible light, the electrons photogenerated from GR transfer to the conduction band of ZnS to participate in the photocatalytic process. This study presents the visible-light photocatalytic activity of wide bandgap ZnS and its application in H2 evolution.

  1. A community-wide campaign to promote physical activity in middle-aged and elderly people: a cluster randomized controlled trial

    PubMed Central

    2013-01-01

    Background We aimed to evaluate the effectiveness of a community-wide campaign (CWC) for promoting physical activity in middle-aged and elderly people. Methods A cluster randomized controlled trial (RCT) with a community as the unit of randomization was performed using a population-based random-sampled evaluation by self-administered questionnaires in the city of Unnan, Shimane Prefecture, Japan. The evaluation sample included 6000 residents aged 40 to 79 years. We randomly allocated nine communities to the intervention group and three to the control group. The intervention was a CWC from 2009 to 2010 to promote physical activity, and it comprised information, education, and support delivery. The primary outcome was a change in engaging in regular aerobic, flexibility, and/or muscle-strengthening activities evaluated at the individual level. Results In total, 4414 residents aged 40–79 years responded to a self-administered questionnaire (73.6% response rate). Awareness of the CWC was 79% in the intervention group. Awareness and knowledge were significantly different between the intervention and control groups, although there were no significant differences in belief and intention. The 1-year CWC did not significantly promote the recommended level of physical activity (adjusted odds ratio: 0.97; 95% confidence interval: 0.84–1.14). Conclusions This cluster RCT showed that the CWC did not promote physical activity in 1 year. Significant differences were observed in awareness and knowledge between intervention and control groups as short-term impacts of the campaign. Trial registration UMIN-CTR UMIN000002683 PMID:23570536

  2. Optical electrocorticogram (OECoG) using wide-field calcium imaging reveals the divergence of neuronal and glial activity during acute rodent seizures.

    PubMed

    Daniel, Andy G S; Laffont, Philippe; Zhao, Mingrui; Ma, Hongtao; Schwartz, Theodore H

    2015-08-01

    The role of glia in epilepsy has been widely debated. Using in vivo bulk loading of calcium dyes, we imaged neuronal and glial activity in an acute pharmacologic rodent model of neocortical seizures. Optical calcium-based ECoG maps revealed that neuronal waves propagated rapidly and remained mostly confined to the seizure focus. Glial waves were triggered by ictal onset but propagated slowly in a stereotypical fashion far beyond the seizure focus. Although related at their onset, the divergence of these two phenomena during seizure evolution calls into question their interdependence and the criticality of the role of glia in seizure onset and neurovascular coupling. This article is part of a Special Issue entitled "Status Epilepticus".

  3. Identification of striated muscle activator of Rho signaling (STARS) as a novel calmodulin target by a newly developed genome-wide screen.

    PubMed

    Furuya, Yusui; Denda, Miwako; Sakane, Kyohei; Ogusu, Tomoko; Takahashi, Sumio; Magari, Masaki; Kanayama, Naoki; Morishita, Ryo; Tokumitsu, Hiroshi

    2016-07-01

    To search for novel target(s) of the Ca(2+)-signaling transducer, calmodulin (CaM), we performed a newly developed genome-wide CaM interaction screening of 19,676 GST-fused proteins expressed in human. We identified striated muscle activator of Rho signaling (STARS) as a novel CaM target and characterized its CaM binding ability and found that the Ca(2+)/CaM complex interacted stoichiometrically with the N-terminal region (Ala13-Gln35) of STARS in vitro as well as in living cells. Mutagenesis studies identified Ile20 and Trp33 as the essential hydrophobic residues in CaM anchoring. Furthermore, the CaM binding deficient mutant (Ile20Ala, Trp33Ala) of STARS further enhanced its stimulatory effect on SRF-dependent transcriptional activation. These results suggest a connection between Ca(2+)-signaling via excitation-contraction coupling and the regulation of STARS-mediated gene expression in muscles.

  4. Genome-wide identification of hypoxia-inducible factor-1 and -2 binding sites in hypoxic human macrophages alternatively activated by IL-10.

    PubMed

    Tausendschön, Michaela; Rehli, Michael; Dehne, Nathalie; Schmidl, Christian; Döring, Claudia; Hansmann, Martin-Leo; Brüne, Bernhard

    2015-01-01

    Macrophages (MΦ) often accumulate in hypoxic areas, where they significantly influence disease progression. Anti-inflammatory cytokines, such as IL-10, generate alternatively activated macrophages that support tumor growth. To understand how alternative activation affects the transcriptional profile of hypoxic macrophages, we globally mapped binding sites of hypoxia-inducible factor (HIF)-1α and HIF-2α in primary human monocyte-derived macrophages prestimulated with IL-10. 713 HIF-1 and 795 HIF-2 binding sites were identified under hypoxia. Pretreatment with IL-10 altered the binding pattern, with 120 new HIF-1 and 188 new HIF-2 binding sites emerging. HIF-1 binding was most prominent in promoters, while HIF-2 binding was more abundant in enhancer regions. Comparison of ChIP-seq data obtained in other cells revealed a highly cell type specific binding of HIF. In MΦ HIF binding occurred preferentially in already active enhancers or promoters. To assess the roles of HIF on gene expression, primary human macrophages were treated with siRNA against HIF-1α or HIF-2α, followed by genome-wide gene expression analysis. Comparing mRNA expression to the HIF binding profile revealed a significant enrichment of hypoxia-inducible genes previously identified by ChIP-seq. Analysis of gene expression under hypoxia alone and hypoxia/IL-10 showed the enhanced induction of a set of genes including PLOD2 and SLC2A3, while another group including KDM3A and ADM remained unaffected or was reduced by IL-10. Taken together IL-10 influences the DNA binding pattern of HIF and the level of gene induction.

  5. Genome Wide Mapping of NR4A Binding Reveals Cooperativity with ETS Factors to Promote Epigenetic Activation of Distal Enhancers in Acute Myeloid Leukemia Cells

    PubMed Central

    Duren, Ryan P.; Boudreaux, Seth P.; Conneely, Orla M.

    2016-01-01

    Members of the NR4A subfamily of orphan nuclear receptors regulate cell fate decisions via both genomic and non-genomic mechanisms in a cell and tissue selective manner. NR4As play a key role in maintenance of hematopoietic stem cell homeostasis and are critical tumor suppressors of acute myeloid leukemia (AML). Expression of NR4As is broadly silenced in leukemia initiating cell enriched populations from human patients relative to normal hematopoietic stem/progenitor cells. Rescue of NR4A expression in human AML cells inhibits proliferation and reprograms AML gene signatures via transcriptional mechanisms that remain to be elucidated. By intersecting an acutely regulated NR4A1 dependent transcriptional profile with genome wide NR4A binding distribution, we now identify an NR4A targetome of 685 genes that are directly regulated by NR4A1. We show that NR4As regulate gene transcription primarily through interaction with distal enhancers that are co-enriched for NR4A1 and ETS transcription factor motifs. Using a subset of NR4A activated genes, we demonstrate that the ETS factors ERG and FLI-1 are required for activation of NR4A bound enhancers and NR4A target gene induction. NR4A1 dependent recruitment of ERG and FLI-1 promotes binding of p300 histone acetyltransferase to epigenetically activate NR4A bound enhancers via acetylation at histone H3K27. These findings disclose novel epigenetic mechanisms by which NR4As and ETS factors cooperate to drive NR4A dependent gene transcription in human AML cells. PMID:26938745

  6. Safety assessment of widely used fermented virgin coconut oil (Cocos nucifera) in Malaysia: Chronic toxicity studies and SAR analysis of the active components.

    PubMed

    Ibrahim, Ahmad H; Khan, Md Shamsuddin Sultan; Al-Rawi, Sawsan S; Ahamed, Mohamed B Khadeer; Majid, Aman Shah Bin Abdul; Al-Suede, Fouad Saleih R; Ji, Dan; Majid, Amin Malik Shah Abdul

    2016-11-01

    Fermented Virgin Coconut Oil (FVCO) is widely used in the Southeast Asia as food and traditional medicine. The objective of the present study is the evaluation of chronic safety of the commercialized FVCO of Malaysia and other Southeast Asian countries. A single dose of 5000 mg/kg of FVCO was administered orally in rats (each group, n = 5) for the acute toxicity study and 175, 550 and 2000 mg/kg for sub-chronic and chronic studies (each group, n = 10), respectively. The behavior, mortality, and body weight of the rats were assessed to determine the toxic effects of FVCO. The haematology, biochemistry and histopathology of the treated rats were evaluated. The treated rats were safe with the dose of 5000 mg/kg in acute, sub-chronic and chronic indication. Abnormal clinical signs and morphology (gross necroscopy), changes of organ weight, anomalous haematology and biochemistry indexes were not found in comparison with the control (p > 0.05). In general, food and water intake were higher in the treated rats related to control. It was concluded that the presence of the antioxidant active compounds of FVCO might be the reason of safety. The structure activity relationship (SAR) provides a comprehensive mechanism to determine the safety that is the presence of the electron donating phenolic groups, carbonyl groups, and carboxylic acid in the ortho and meta position of the aromatic rings. The SAR showed the antioxidant properties of myristic acid and lauric acid determined by GC-MS analysis. This result suggests the safety of FVCO for chronic use, nutritional activity that FVCO formulation complies the requirements of regulatory agencies.

  7. Effects of combined electrical stimulation of the dorsal column and dorsal roots on wide-dynamic range neuronal activity in nerve-injured rats

    PubMed Central

    Yang, Fei; Zhang, Tong; Tiwari, Vinod; Shu, Bin; Zhang, Chen; Wang, Yun; Vera-Portocarrero, Louis P.; Raja, Srinivasa N.; Guan, Yun

    2015-01-01

    Objectives Electrical stimulation at the dorsal column (DC) and dorsal root (DR) may inhibit spinal wide-dynamic-range (WDR) neuronal activity in nerve-injured rats. The objective of this study was to determine if applying electrical conditioning stimulation (CS) at both sites provides additive or synergistic benefits. Materials and Methods By conducting in vivo extracellular recordings of WDR neurons in rats that had undergone L5 spinal nerve ligation, we tested whether combining 50 Hz CS at the two sites in either a concurrent (2.5 minutes) or alternate (5 minutes) pattern inhibits WDR neuronal activity better than CS at DC alone (5 minutes). The intensities of CS were determined by recording antidromic compound action potentials to graded stimulation at the DC and DR. We measured the current thresholds that resulted in the first detectable Aα/β waveform (Ab0) and the peak Aα/β waveform (Ab1) to select CS intensity at each site. The same number of electrical pulses and amount of current were delivered in different patterns to allow comparison. Results At a moderate intensity of 50%(Ab0+Ab1), different patterns of CS all attenuated the C-component of WDR neurons in response to graded intracutaneous electrical stimuli (0.1-10 mA, 2 ms), and inhibited windup in response to repetitive noxious stimuli (0.5 Hz). However, the inhibitory effects did not differ significantly between different patterns. At the lower intensity (Ab0), no CS inhibited WDR neurons. Conclusions These findings suggest that combined stimulation of DC and DR may not be superior to DC stimulation alone for inhibition of WDR neurons. PMID:26307526

  8. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide

    PubMed Central

    Zhang, Si-Ming; Buddenborg, Sarah K.; Adema, Coen M.; Sullivan, John T.; Loker, Eric S.

    2015-01-01

    In view of the call by the World Health Organization (WHO) for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy–based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biology and may offer valuable insights into the development of better chemical control methods for snails. We used a recently developed Biomphalaria glabrata oligonucleotide microarray (31K features) to investigate the effect of sublethal exposure to niclosamide on the transcriptional responses of the snail B. glabrata relative to untreated snails. Most of the genes highly upregulated following exposure of snails to niclosamide are involved in biotransformation of xenobiotics, including genes encoding cytochrome P450s (CYP), glutathione S-transferases (GST), and drug transporters, notably multi-drug resistance protein (efflux transporter) and solute linked carrier (influx transporter). Niclosamide also induced stress responses. Specifically, six heat shock protein (HSP) genes from three super-families (HSP20, HSP40 and HSP70) were upregulated. Genes encoding ADP-ribosylation factor (ARF), cAMP response element-binding protein (CREB) and coatomer, all of which are involved in vesicle trafficking in the Golgi of mammalian cells, were also upregulated. Lastly, a hemoglobin gene was downregulated, suggesting niclosamide may affect oxygen transport. Our results show that snails mount substantial responses to sublethal concentrations of niclosamide, at least some of which appear to be protective. The topic of how niclosamide’s lethality at higher concentrations is determined requires further study. Given that niclosamide has also been used as an anthelmintic drug for decades and has

  9. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide.

    PubMed

    Zhang, Si-Ming; Buddenborg, Sarah K; Adema, Coen M; Sullivan, John T; Loker, Eric S

    2015-01-01

    In view of the call by the World Health Organization (WHO) for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy-based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biology and may offer valuable insights into the development of better chemical control methods for snails. We used a recently developed Biomphalaria glabrata oligonucleotide microarray (31K features) to investigate the effect of sublethal exposure to niclosamide on the transcriptional responses of the snail B. glabrata relative to untreated snails. Most of the genes highly upregulated following exposure of snails to niclosamide are involved in biotransformation of xenobiotics, including genes encoding cytochrome P450s (CYP), glutathione S-transferases (GST), and drug transporters, notably multi-drug resistance protein (efflux transporter) and solute linked carrier (influx transporter). Niclosamide also induced stress responses. Specifically, six heat shock protein (HSP) genes from three super-families (HSP20, HSP40 and HSP70) were upregulated. Genes encoding ADP-ribosylation factor (ARF), cAMP response element-binding protein (CREB) and coatomer, all of which are involved in vesicle trafficking in the Golgi of mammalian cells, were also upregulated. Lastly, a hemoglobin gene was downregulated, suggesting niclosamide may affect oxygen transport. Our results show that snails mount substantial responses to sublethal concentrations of niclosamide, at least some of which appear to be protective. The topic of how niclosamide's lethality at higher concentrations is determined requires further study. Given that niclosamide has also been used as an anthelmintic drug for decades and has been

  10. Development of an advanced pitch active control system and a reduced area horizontal tail for a wide-body jet aircraft

    NASA Technical Reports Server (NTRS)

    Guinn, Wiley A.

    1984-01-01

    The development of an advanced pitch active control system (PACS) and a reduced area horizontal tail for a wide-body jet transport (L-1011) with a flying horizontal stabilizer is discussed. The advanced PACS control law design objectives were to provide satisfactory handling qualities for aft c.g. flight conditions to negative static stability margins of 10 percent and to provide good maneuver control column force gradients for nonlinear stability flight conditions. Validity of the control laws were demonstrated by piloted flight simulation tests on the NASA Langley Visual Motion Simulator. Satisfactory handling qualities were actually demonstrated to a negative 20 percent static stability margin. The PACS control laws were mechanized to provide the system architecture that would be suitable for an L-1011 flight test program to a negative stability margin of 3 percent which represents the aft c.g. limits of the aircraft. Reduced area horizontal tail designs of 30 and 38 percent with respect to the L-1011 standard tail were designed, fabricated and wind tunnel tested. Drag reductions and weight savings of the 30 percent smaller tail would provide an L/D benefit of about 2% and the 38% small tail L/D benefit would be about 3 percent. However, forward c.g. limitations would have to be imposed on the aircraft because the maximum horizontal tail lift goal was not achieved and sufficient aircraft nose-up control authority was not available. This limitation would not be required for a properly designed new aircraft.

  11. On R-W1 as A Diagnostic to Discover Obscured Active Galactic Nuclei in Wide-area X-Ray Surveys

    NASA Astrophysics Data System (ADS)

    LaMassa, Stephanie M.; Civano, Francesca; Brusa, Marcella; Stern, Daniel; Glikman, Eilat; Gallagher, Sarah; Urry, C. Meg; Cales, Sabrina; Cappelluti, Nico; Cardamone, Carolin; Comastri, Andrea; Farrah, Duncan; Greene, Jenny E.; Komossa, S.; Merloni, Andrea; Mroczkowski, Tony; Natarajan, Priyamvada; Richards, Gordon; Salvato, Mara; Schawinski, Kevin; Treister, Ezequiel

    2016-02-01

    Capitalizing on the all-sky coverage of WISE and the 35% and 50% sky coverage from Sloan Digital Sky Survey and Pan-STARRS, respectively, we explore the efficacy of mR (optical) - {m}3.4μ {{m}} (mid-infrared), hereafter R-W1, as a color diagnostic to identify obscured supermassive black hole accretion in wide-area X-ray surveys. We use the ˜16.5 deg2 Stripe 82 X-ray survey data as a test bed to compare R-W1 with R - K, an oft-used obscured active galactic nucleus (AGN) selection criterion, and examine where different classes of objects lie in this parameter space. Most stars follow a well-defined path in R - K versus R-W1 space. We demonstrate that optically normal galaxies hosting X-ray AGNs at redshifts 0.5\\lt z\\lt 1 can be recovered with an R-W1\\gt 4 color cut, while they typically are not selected as AGNs based on their W1-W2 colors. Additionally, different observed X-ray luminosity bins favor different regions in R-W1 parameter space: moderate-luminosity AGNs (1043 erg {{{s}}}-1\\lt {L}0.5-10{keV}\\lt {10}44 erg s-1) tend to have red colors, while the highest-luminosity AGNs ({L}0.5-10{keV}\\gt {10}45 erg s-1) have bluer colors; higher spectroscopic completeness of the Stripe 82X sample is needed to determine whether this is a selection effect or an intrinsic property. Finally, we parameterize X-ray obscuration of Stripe 82X AGNs by calculating their hardness ratios (HRs) and find no clear trends between HR and optical reddening. Our results will help inform best-effort practices in following up obscured AGN candidates in current and future wide-area, shallow X-ray surveys, including the all-sky eROSITA mission.

  12. Genome-wide DNA methylation identifies trophoblast invasion-related genes: Claudin-4 and Fucosyltransferase IV control mobility via altering matrix metalloproteinase activity.

    PubMed

    Hu, Yuxiang; Blair, John D; Yuen, Ryan K C; Robinson, Wendy P; von Dadelszen, Peter

    2015-05-01

    Previously we showed that extravillous cytotrophoblast (EVT) outgrowth and migration on a collagen gel explant model were affected by exposure to decidual natural killer cells (dNK). This study investigates the molecular causes behind this phenomenon. Genome wide DNA methylation of exposed and unexposed EVT was assessed using the Illumina Infinium HumanMethylation450 BeadChip array (450 K array). We identified 444 differentially methylated CpG loci in dNK-treated EVT compared with medium control (P < 0.05). The genes associated with these loci had critical biological roles in cellular development, cellular growth and proliferation, cell signaling, cellular assembly and organization by Ingenuity Pathway Analysis (IPA). Furthermore, 23 mobility-related genes were identified by IPA from dNK-treated EVT. Among these genes, CLDN4 (encoding claudin-4) and FUT4 (encoding fucosyltransferase IV) were chosen for follow-up studies because of their biological relevance from research on tumor cells. The results showed that the mRNA and protein expressions of both CLDN4 and FUT4 in dNK-treated EVT were significantly reduced compared with control (P < 0.01 for both CLDN4 and FUT4 mRNA expression; P < 0.001 for CLDN4 and P < 0.01 for FUT4 protein expression), and were inversely correlated with DNA methylation. Knocking down CLDN4 and FUT4 by small interfering RNA reduced trophoblast invasion, possibly through the altered matrix metalloproteinase (MMP)-2 and/or MMP-9 expression and activity. Taken together, dNK alter EVT mobility at least partially in association with an alteration of DNA methylation profile. Hypermethylation of CLDN4 and FUT4 reduces protein expression. CLDN4 and FUT4 are representative genes that participate in modulating trophoblast mobility.

  13. Genome-wide cooperation by HAT Gcn5, remodeler SWI/SNF, and chaperone Ydj1 in promoter nucleosome eviction and transcriptional activation

    PubMed Central

    Qiu, Hongfang; Chereji, Răzvan V.; Hu, Cuihua; Cole, Hope A.; Rawal, Yashpal; Clark, David J.; Hinnebusch, Alan G.

    2016-01-01

    Chaperones, nucleosome remodeling complexes, and histone acetyltransferases have been implicated in nucleosome disassembly at promoters of particular yeast genes, but whether these cofactors function ubiquitously, as well as the impact of nucleosome eviction on transcription genome-wide, is poorly understood. We used chromatin immunoprecipitation of histone H3 and RNA polymerase II (Pol II) in mutants lacking single or multiple cofactors to address these issues for about 200 genes belonging to the Gcn4 transcriptome, of which about 70 exhibit marked reductions in H3 promoter occupancy on induction by amino acid starvation. Examining four target genes in a panel of mutants indicated that SWI/SNF, Gcn5, the Hsp70 cochaperone Ydj1, and chromatin-associated factor Yta7 are required downstream from Gcn4 binding, whereas Asf1/Rtt109, Nap1, RSC, and H2AZ are dispensable for robust H3 eviction in otherwise wild-type cells. Using ChIP-seq to interrogate all 70 exemplar genes in single, double, and triple mutants implicated Gcn5, Snf2, and Ydj1 in H3 eviction at most, but not all, Gcn4 target promoters, with Gcn5 generally playing the greatest role and Ydj1 the least. Remarkably, these three cofactors cooperate similarly in H3 eviction at virtually all yeast promoters. Defective H3 eviction in cofactor mutants was coupled with reduced Pol II occupancies for the Gcn4 transcriptome and the most highly expressed uninduced genes, but the relative Pol II levels at most genes were unaffected or even elevated. These findings indicate that nucleosome eviction is crucial for robust transcription of highly expressed genes but that other steps in gene activation are more rate-limiting for most other yeast genes. PMID:26602697

  14. A Genome-Wide Identified Risk Variant for PTSD is a Methylation Quantitative Trait Locus and Confers Decreased Cortical Activation to Fearful Faces

    DTIC Science & Technology

    2015-05-18

    post - traumatic stress disorder (PTSD). In a discovery sample, we conducted a ge- nome-wide...development of post - traumatic stress disorder (PTSD). In a discovery sample, we conducted a genome-wide association study (GWAS) for PTSD using a small...development; PTSD, post - traumatic stress disorder . aETISR total [Bremner et al., 2000]. bCAPS [Blake et al., 1995]. cPCL-M [Weathers et al., 2013]. dBDI

  15. On Varying-coefficient Independence Screening for High-dimensional Varying-coefficient Models.

    PubMed

    Song, Rui; Yi, Feng; Zou, Hui

    2014-01-01

    Varying coefficient models have been widely used in longitudinal data analysis, nonlinear time series, survival analysis, and so on. They are natural non-parametric extensions of the classical linear models in many contexts, keeping good interpretability and allowing us to explore the dynamic nature of the model. Recently, penalized estimators have been used for fitting varying-coefficient models for high-dimensional data. In this paper, we propose a new computationally attractive algorithm called IVIS for fitting varying-coefficient models in ultra-high dimensions. The algorithm first fits a gSCAD penalized varying-coefficient model using a subset of covariates selected by a new varying-coefficient independence screening (VIS) technique. The sure screening property is established for VIS. The proposed algorithm then iterates between a greedy conditional VIS step and a gSCAD penalized fitting step. Simulation and a real data analysis demonstrate that IVIS has very competitive performance for moderate sample size and high dimension.

  16. On Varying-coefficient Independence Screening for High-dimensional Varying-coefficient Models

    PubMed Central

    Song, Rui; Yi, Feng; Zou, Hui

    2014-01-01

    Varying coefficient models have been widely used in longitudinal data analysis, nonlinear time series, survival analysis, and so on. They are natural non-parametric extensions of the classical linear models in many contexts, keeping good interpretability and allowing us to explore the dynamic nature of the model. Recently, penalized estimators have been used for fitting varying-coefficient models for high-dimensional data. In this paper, we propose a new computationally attractive algorithm called IVIS for fitting varying-coefficient models in ultra-high dimensions. The algorithm first fits a gSCAD penalized varying-coefficient model using a subset of covariates selected by a new varying-coefficient independence screening (VIS) technique. The sure screening property is established for VIS. The proposed algorithm then iterates between a greedy conditional VIS step and a gSCAD penalized fitting step. Simulation and a real data analysis demonstrate that IVIS has very competitive performance for moderate sample size and high dimension. PMID:25484548

  17. Fluorine doping: a feasible solution to enhancing the conductivity of high-resistance wide bandgap Mg0.51Zn0.49O active components

    PubMed Central

    Liu, Lishu; Mei, Zengxia; Hou, Yaonan; Liang, Huili; Azarov, Alexander; Venkatachalapathy, Vishnukanthan; Kuznetsov, Andrej; Du, Xiaolong

    2015-01-01

    N-type doping of high-resistance wide bandgap semiconductors, wurtzite high-Mg-content MgxZn1–xO for instance, has always been a fundamental application-motivated research issue. Herein, we report a solution to enhancing the conductivity of high-resistance Mg0.51Zn0.49O active components, which has been reliably achieved by fluorine doping via radio-frequency plasma assisted molecular beam epitaxial growth. Fluorine dopants were demonstrated to be effective donors in Mg0.51Zn0.49O single crystal film having a solar-blind 4.43 eV bandgap, with an average concentration of 1.0 × 1019 F/cm3.The dramatically increased carrier concentration (2.85 × 1017 cm−3 vs ~1014 cm−3) and decreased resistivity (129 Ω · cm vs ~106 Ω cm) indicate that the electrical properties of semi-insulating Mg0.51Zn0.49O film can be delicately regulated by F doping. Interestingly, two donor levels (17 meV and 74 meV) associated with F were revealed by temperature-dependent Hall measurements. A Schottky type metal-semiconductor-metal ultraviolet photodetector manifests a remarkably enhanced photocurrent, two orders of magnitude higher than that of the undoped counterpart. The responsivity is greatly enhanced from 0.34 mA/W to 52 mA/W under 10 V bias. The detectivity increases from 1.89 × 109 cm Hz1/2/W to 3.58 × 1010 cm Hz1/2/W under 10 V bias at room temperature.These results exhibit F doping serves as a promising pathway for improving the performance of high-Mg-content MgxZn1-xO-based devices. PMID:26489958

  18. Genome-Wide Association Study for Circulating Tissue Plasminogen Activator (tPA) Levels and Functional Follow-up Implicates Endothelial STXBP5 and STX2

    PubMed Central

    Huang, Jie; Huffman, Jennifer E.; Yamkauchi, Munekazu; Trompet, Stella; Asselbergs, Folkert W.; Sabater-Lleal, Maria; Trégouët, David-Alexandre; Chen, Wei-Min; Smith, Nicholas L.; Kleber, Marcus E.; Shin, So-Youn; Becker, Diane M.; Tang, Weihong; Dehghan, Abbas; Johnson, Andrew D.; Truong, Vinh; Folkersen, Lasse; Yang, Qiong; Oudot-Mellakh, Tiphaine; Buckley, Brendan M.; Moore, Jason H.; Williams, Frances M.K.; Campbell, Harry; Silbernagel, Günther; Vitart, Veronique; Rudan, Igor; Tofler, Geoffrey H.; Navis, Gerjan J.; DeStefano, Anita; Wright, Alan F.; Chen, Ming-Huei; de Craen, Anton J.M.; Worrall, Bradford B.; Rudnicka, Alicja R.; Rumley, Ann; Bookman, Ebony B.; Psaty, Bruce M.; Chen, Fang; Keene, Keith L.; Franco, Oscar H.; Böhm, Bernhard O.; Uitterlinden, Andre G.; Carter, Angela M.; Jukema, J. Wouter; Sattar, Naveed; Bis, Joshua C.; Ikram, Mohammad A.; Sale, Michèle M.; McKnight, Barbara; Fornage, Myriam; Ford, Ian; Taylor, Kent; Slagboom, P. Eline; McArdle, Wendy L.; Hsu, Fang-Chi; Franco-Cereceda, Anders; Goodall, Alison H.; Yanek, Lisa R.; Furie, Karen L.; Cushman, Mary; Hofman, Albert; Witteman, Jacqueline CM.; Folsom, Aaron R.; Basu, Saonli; Matijevic, Nena; van Gilst, Wiek H.; Wilson, James F.; Westendorp, Rudi G.J.; Kathiresan, Sekar; Reilly, Muredach P.; Tracy, Russell P.; Polasek, Ozren; Winkelmann, Bernhard R.; Grant, Peter J.; Hillege, Hans L.; Cambien, Francois; Stott, David J.; Lowe, Gordon D.; Spector, Timothy D.; Meigs, James B.; Marz, Winfried; Eriksson, Per; Becker, Lewis C.; Morange, Pierre-Emmanuel; Soranzo, Nicole; Williams, Scott M.; Hayward, Caroline; van der Harst, Pim; Hamsten, Anders; Lowenstein, Charles J.; Strachan, David P.; O'Donnell, Christopher J.

    2014-01-01

    Objective Tissue plasminogen activator (tPA), a serine protease, catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for endogenous fibrinolysis. In some populations, elevated plasma levels of tPA have been associated with myocardial infarction and other cardiovascular diseases (CVD). We conducted a meta-analysis of genome-wide association studies (GWAS) to identify novel correlates of circulating levels of tPA. Approach and Results Fourteen cohort studies with tPA measures (N=26,929) contributed to the meta-analysis. Three loci were significantly associated with circulating tPA levels (P <5.0×10−8). The first locus is on 6q24.3, with the lead SNP (rs9399599, P=2.9×10−14) within STXBP5. The second locus is on 8p11.21. The lead SNP (rs3136739, P=1.3×10−9) is intronic to POLB and less than 200kb away from the tPA encoding gene PLAT. We identified a non-synonymous SNP (rs2020921) in modest LD with rs3136739 (r2 = 0.50) within exon 5 of PLAT (P=2.0×10−8). The third locus is on 12q24.33, with the lead SNP (rs7301826, P=1.0×10−9) within intron 7 of STX2. We further found evidence for association of lead SNPs in STXBP5 and STX2 with expression levels of the respective transcripts. In in vitro cell studies, silencing STXBP5 decreased release of tPA from vascular endothelial cells, while silencing of STX2 increased tPA release. Through an in-silico lookup, we found no associations of the three lead SNPs with coronary artery disease or stroke. Conclusions We identified three loci associated with circulating tPA levels, the PLAT region, STXBP5 and STX2. Our functional studies implicate a novel role for STXBP5 and STX2 in regulating tPA release. PMID:24578379

  19. Resistance to glufosinate is proportional to phosphinothricin acetyltransferase expression and activity in LibertyLink® and WideStrike® Cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    LibertyLink® cotton cultivars are engineered for glufosinate resistance by overexpressing the bar gene that encodes phosphinothricin acetyltransferase (PAT), whereas the insect-resistant WideStrike® cultivars were obtained by using the similar pat gene as a selectable marker. The latter cultivars ca...

  20. Varying Constants, Gravitation and Cosmology.

    PubMed

    Uzan, Jean-Philippe

    2011-01-01

    Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. Thus, it is of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, solar system observations, meteorite dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.

  1. Wide-range CCD spectrometer

    NASA Astrophysics Data System (ADS)

    Sokolova, Elena A.; Reyes Cortes, Santiago D.

    1996-08-01

    The utilization of wide range spectrometers is a very important feature for the design of optical diagnostics. This paper describes an innovative approach, based on charged coupled device, which allows to analyze different spectral intervals with the same diffraction grating. The spectral interval is varied by changing the position of the entrance slit when the grating is stationary. The optical system can also include a spherical mirror. In this case the geometric position of the mirror is calculated aiming at compensating the first order astigmatism and the meridional coma of the grating. This device is planned to be used in Thomson scattering diagnostic of the TOKAMAK of Instituto Superior Tecnico, Lisbon (ISTTOK).

  2. Wide band data collection system

    NASA Technical Reports Server (NTRS)

    Turkiewicz, J. M.

    1988-01-01

    The Incorporated Research Institutes for Seismology (IRIS) approached NASA Headquarters in 1986 about the need to collect data daily from seismic stations around the world as part of the Earth Observing System (EOS) mission. A typical IRIS Seismic Station generates 16 Megabytes of data per day when there is seismic activity. The Preliminary Design Parameters of the Wide Band Data Collection System are summarized.

  3. Partnership in Sector Wide Approaches

    ERIC Educational Resources Information Center

    Tolley, Hilary

    2011-01-01

    Within the context of bilateral support to the education sector in Tonga and the Solomon Islands, this paper will explore how the discourse of "partnership" has been interpreted and activated within the Sector wide approach (SWAp). In concentrating particularly on the relationship between the respective Ministries of Education and New…

  4. Dynamic Factor Analysis Models with Time-Varying Parameters

    ERIC Educational Resources Information Center

    Chow, Sy-Miin; Zu, Jiyun; Shifren, Kim; Zhang, Guangjian

    2011-01-01

    Dynamic factor analysis models with time-varying parameters offer a valuable tool for evaluating multivariate time series data with time-varying dynamics and/or measurement properties. We use the Dynamic Model of Activation proposed by Zautra and colleagues (Zautra, Potter, & Reich, 1997) as a motivating example to construct a dynamic factor…

  5. Wide variability in physical activity environments and weather-related outdoor play policies in child-care centers within a single county of Ohio

    PubMed Central

    Copeland, Kristen A; Sherman, Susan N; Khoury, Jane C; Foster, Karla E; Saelens, Brian E; Kalkwarf, Heidi J

    2011-01-01

    Objectives To examine the variability of physical activity environments and outdoor play-policies in child-care centers, and to determine if they are associated with center demographic characteristics Design Telephone survey—the Early Learning Environments Physical Activity and Nutrition Telephone Survey (ELEPhANTS) Setting Child-care centers in Hamilton County (Cincinnati area), Ohio, 2008–9. Participants Directors of all 185 licensed full-time child-care centers in Hamilton County. Outcome Measures Descriptive measures of center playground and indoor physical activity environments, and weather-related outdoor-play policies. Results 162 (88%) centers responded. Most (93%) centers reported an on-site playground, but only half reported their playgrounds as large, at least 1/3rd covered in shade, or having a variety of portable play equipment. Only half reported having a dedicated indoor gross-motor room where children could be active during inclement weather. Only 20% of centers allowed children to go outside in temperatures below 32°F, and 43% of centers reported allowing children outdoors during light rain. A higher percent of children receiving tuition-assistance was associated with lower quality physical activity facilities and stricter weather-related practices. National accreditation was associated with more physical-activity promoting practices. Conclusion We found considerable variability in the indoor and outdoor playground offerings among child-care centers, even within a single county of Ohio. Per center policy and limited inside options, children’s active opportunities are curtailed due to sub-freezing temperatures or light rain. Policy change and parent/teacher education may be needed to ensure children achieve ample opportunity for daily physical activity. PMID:21199969

  6. Retention: Rates and Practices Vary from Campus to Campus.

    ERIC Educational Resources Information Center

    Boulard, Garry

    1994-01-01

    Although college student retention rates vary widely by institution, educators feel dropout prevention is improving and results from a variety of strategies. Teacher awareness training, better student monitoring, and enhanced support networks and services are credited for the improvement. Some policies concerning academic probation, suspension,…

  7. Ozone inhalation effects in females varying widely in lung size: Comparison with males

    SciTech Connect

    Messineo, T.D.; Adams, W.C. )

    1990-07-01

    It has been suggested that lung size accounts for observed gender differences in responsiveness to the same total inhaled dose of O3. To test the hypothesis that lung size is a determinant of magnitude of response within a gender, two groups of 14 healthy young adult females differing significantly in forced vital capacity (FVC; i.e., small-lung group mean = 3.74 liters (range 3.2-4.0) and large-lung group mean = 5.11 liters (range 4.5-6.2)) were exposed for 1 h to filtered air (FA) and to 0.18 and 0.30 ppm O3. On each occasion, subjects exercised continuously on a cycle ergometer at a work rate that elicited a mean minute ventilation of approximately 47 l/min. For the small-lung group (mean total lung capacity (TLC) = 4.52 liters) exercise O2 uptake was 67% of maximal O2 uptake (VO2max), and that for the large-lung group (TLC 6.37 liters) was 61% of VO2max. Statistical analysis revealed significant decrements for both groups in FVC, forced expiratory volume in 1 s (FEV1.0), and forced expiratory flow rate in the middle half of FVC on exposure to 0.18 and 0.30 ppm O3. Exercise respiratory frequency increased, and tidal volume decreased significantly in both groups in response to 0.18 and 0.30 ppm O3 exposure. On exposure to 0.30 ppm O3, the number of individual subjective symptoms reported and their severity were significantly greater for both groups than those reported for the FA and 0.18 ppm O3 exposures. Both groups evidenced similar percent changes in pulmonary function and exercise ventilation response, and in subjective symptom response.

  8. Going Wide, Not Wild: Varying Conceptualizations of Internationalization at a University of Technology in South Africa

    ERIC Educational Resources Information Center

    Meda, Lawrence; Monnapula-Mapesela, Mabokang

    2016-01-01

    Internationalization has become a buzzword in universities today. As a result of the breadth of the term the concept lends itself to many interpretations. There is a view that South African higher education does not have a customized national framework of internationalization, which raises questions about whether the intended outcomes are…

  9. Shock hugoniot behavior of mixed phases with widely varying shock imepdances

    SciTech Connect

    Reaugh, J.E.; Lee, E.L.

    1997-07-01

    The shock velocity dependence on shock pressure in composite explosive materials containing polymeric binders is known to exhibit marked non-linear behavior in the U{sub s} - u{sub p} plane at low pressures. This is in addition to the non-linear behavior noted in pure polymeric materials. The precise description of this behavior is important in analyzing the response of energetic materials to impact shocks. We will show that the mismatch of the shock impedances in materials such as rocket propellants composed of polymer binder, aluminum, and ammonium Perchlorate can be expected to exhibit a very large initial slope of the shock velocity, U{sub s}, dependence on the particle velocity, u{sub p}. This slope is simply a result of the equilibration of Hugoniot pressure amongst the phases. With accurate descriptions for the equations of state of the individual components, we successfully predict the extreme slope at low compression. The effect is primarily due to the very large change in compressibility of the polymeric phase at relatively low volumetric compression of the whole mixture. Examples are shown and compared with available experimental results.

  10. Many Options in New Orleans Choice System: School Characteristics Vary Widely

    ERIC Educational Resources Information Center

    Arce-­Trigatti, Paula; Harris, Douglas N.; Jabbar, Huriya; Lincove, Jane Arnold

    2015-01-01

    Previous studies have focused on the differences between charter schools and district schools, treating all charters within a community as essentially alike. In effect, these studies take a "top­-down" approach, assuming that the governance of the school (charter versus district) determines the nature of the school. This approach may be…

  11. MID-INFRARED SELECTION OF ACTIVE GALACTIC NUCLEI WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER. II. PROPERTIES OF WISE-SELECTED ACTIVE GALACTIC NUCLEI IN THE NDWFS BOOeTES FIELD

    SciTech Connect

    Assef, R. J.; Stern, D.; Eisenhardt, P. R. M.; Tsai, C.-W.; Kochanek, C. S.; Blain, A. W.; Brodwin, M.; Brown, M. J. I.; Donoso, E.; Jarrett, T. H.; Yan, L.; Jannuzi, B. T.; Stanford, S. A.; Wu, J.

    2013-07-20

    Stern et al. presented a study of Wide-field Infrared Survey Explorer (WISE) selection of active galactic nuclei (AGNs) in the 2 deg{sup 2} COSMOS field, finding that a simple criterion W1-W2 {>=} 0.8 provides a highly reliable and complete AGN sample for W2 < 15.05, where the W1 and W2 passbands are centered at 3.4 {mu}m and 4.6 {mu}m, respectively. Here we extend this study using the larger 9 deg{sup 2} NOAO Deep Wide-Field Survey Booetes field which also has considerably deeper WISE observations than the COSMOS field, and find that this simple color cut significantly loses reliability at fainter fluxes. We define a modified selection criterion combining the W1-W2 color and the W2 magnitude to provide highly reliable or highly complete AGN samples for fainter WISE sources. In particular, we define a color-magnitude cut that finds 130 {+-} 4 deg{sup -2} AGN candidates for W2 < 17.11 with 90% reliability. Using the extensive UV through mid-IR broadband photometry available in this field, we study the spectral energy distributions of WISE AGN candidates. We find that, as expected, the WISE AGN selection can identify highly obscured AGNs, but that it is biased toward objects where the AGN dominates the bolometric luminosity output. We study the distribution of reddening in the AGN sample and discuss a formalism to account for sample incompleteness based on the step-wise maximum-likelihood method of Efstathiou et al. The resulting dust obscuration distributions depend strongly on AGN luminosity, consistent with the trend expected for a receding torus. At L{sub AGN} {approx} 3 Multiplication-Sign 10{sup 44} erg s{sup -1}, 29% {+-} 7% of AGNs are observed as Type 1, while at {approx}4 Multiplication-Sign 10{sup 45} erg s{sup -1} the fraction is 64% {+-} 13%. The distribution of obscuration values suggests that dust in the torus is present as both a diffuse medium and in optically thick clouds.

  12. Genome-wide analysis reveals PADI4 cooperates with Elk-1 to activate c-Fos expression in breast cancer cells.

    PubMed

    Zhang, Xuesen; Gamble, Matthew J; Stadler, Sonja; Cherrington, Brian D; Causey, Corey P; Thompson, Paul R; Roberson, Mark S; Kraus, W Lee; Coonrod, Scott A

    2011-06-01

    Peptidylarginine deiminase IV (PADI4) catalyzes the conversion of positively charged arginine and methylarginine residues to neutrally charged citrulline, and this activity has been linked to the repression of a limited number of target genes. To broaden our knowledge of the regulatory potential of PADI4, we utilized chromatin immunoprecipitation coupled with promoter tiling array (ChIP-chip) analysis to more comprehensively investigate the range of PADI4 target genes across the genome in MCF-7 breast cancer cells. Results showed that PADI4 is enriched in gene promoter regions near transcription start sites (TSSs); and, surprisingly, this pattern of binding is primarily associated with actively transcribed genes. Computational analysis found potential binding sites for Elk-1, a member of the ETS oncogene family, to be highly enriched around PADI4 binding sites; and coimmunoprecipitation analysis then confirmed that Elk-1 physically associates with PADI4. To better understand how PADI4 may facilitate gene transactivation, we then show that PADI4 interacts with Elk-1 at the c-Fos promoter and that, following Epidermal Growth Factor (EGF) stimulation, PADI4 catalytic activity facilitates Elk-1 phosphorylation, histone H4 acetylation, and c-Fos transcriptional activation. These results define a novel role for PADI4 as a transcription factor co-activator.

  13. Emerging issues in improving food and physical activity environments: strategies for addressing land use, transportation, and safety in 3 California-wide initiatives.

    PubMed

    Aboelata, Manal J; Navarro, Amanda M

    2010-11-01

    Mounting research has suggested linkages between neighborhood safety, community design, and transportation patterns and eating and activity behaviors and health outcomes. On the basis of a review of evaluation findings from 3 multisite healthy eating and activity initiatives in California, we provide an overview of 3 community process strategies-engaging local advocates, linking safety to health, and collaborating with local government officials-that may be associated with the successful development and implementation of long-term community-improvement efforts and should be explored further.

  14. Assessing the Feasibility of a Multi-Program School-Based Intervention to Promote Physical Activity and Healthful Eating in Middle Schools Prior to Wide-Scale Implementation

    ERIC Educational Resources Information Center

    Greaney, Mary; Hardwick, Cary K.; Mezgebu, Solomon; Lindsay, Ana C.; Roover, Michelle L.; Peterson, Karen E.

    2007-01-01

    Background: University-community partnerships can support schools in implementing evidence-based responses to youth obesity trends. An inter-organizational partnership was established to implement and evaluate the Healthy Choices Collaborative Intervention (HCCI). HCCI combines an interdisciplinary curriculum, before/after school activities, and…

  15. Armadillidin H, a Glycine-Rich Peptide from the Terrestrial Crustacean Armadillidium vulgare, Displays an Unexpected Wide Antimicrobial Spectrum with Membranolytic Activity

    PubMed Central

    Verdon, Julien; Coutos-Thevenot, Pierre; Rodier, Marie-Helene; Landon, Celine; Depayras, Segolene; Noel, Cyril; La Camera, Sylvain; Moumen, Bouziane; Greve, Pierre; Bouchon, Didier; Berjeaud, Jean-Marc; Braquart-Varnier, Christine

    2016-01-01

    Antimicrobial peptides (AMPs) are key components of innate immunity and are widespread in nature, from bacteria to vertebrate animals. In crustaceans, there are currently 15 distinct AMP families published so far in the literature, mainly isolated from members of the Decapoda order. Up to now, armadillidin is the sole non-decapod AMP isolated from the haemocytes of Armadillidium vulgare, a crustacean isopod. Its first description demonstrated that armadillidin is a linear glycine-rich (47%) cationic peptide with an antimicrobial activity directed toward Bacillus megaterium. In the present work, we report identification of armadillidin Q, a variant of armadillidin H (earlier known as armadillidin), from crude haemocyte extracts of A. vulgare using LC-MS approach. We demonstrated that both armadillidins displayed broad spectrum antimicrobial activity against several Gram-positive and Gram-negative bacteria, fungi, but were totally inactive against yeasts. Membrane permeabilization assays, only performed with armadillidin H, showed that the peptide is membrane active against bacterial and fungal strains leading to deep changes in cell morphology. This damaging activity visualized by electronic microscopy correlates with a rapid decrease of cell viability leading to highly blebbed cells. In contrast, armadillidin H does not reveal cytotoxicity toward human erythrocytes. Furthermore, no secondary structure could be defined in this study [by circular dichroism (CD) and nuclear magnetic resonance (NMR)] even in a membrane mimicking environment. Therefore, armadillidins represent interesting candidates to gain insight into the biology of glycine-rich AMPs. PMID:27713732

  16. Armadillidin H, a Glycine-Rich Peptide from the Terrestrial Crustacean Armadillidium vulgare, Displays an Unexpected Wide Antimicrobial Spectrum with Membranolytic Activity.

    PubMed

    Verdon, Julien; Coutos-Thevenot, Pierre; Rodier, Marie-Helene; Landon, Celine; Depayras, Segolene; Noel, Cyril; La Camera, Sylvain; Moumen, Bouziane; Greve, Pierre; Bouchon, Didier; Berjeaud, Jean-Marc; Braquart-Varnier, Christine

    2016-01-01

    Antimicrobial peptides (AMPs) are key components of innate immunity and are widespread in nature, from bacteria to vertebrate animals. In crustaceans, there are currently 15 distinct AMP families published so far in the literature, mainly isolated from members of the Decapoda order. Up to now, armadillidin is the sole non-decapod AMP isolated from the haemocytes of Armadillidium vulgare, a crustacean isopod. Its first description demonstrated that armadillidin is a linear glycine-rich (47%) cationic peptide with an antimicrobial activity directed toward Bacillus megaterium. In the present work, we report identification of armadillidin Q, a variant of armadillidin H (earlier known as armadillidin), from crude haemocyte extracts of A. vulgare using LC-MS approach. We demonstrated that both armadillidins displayed broad spectrum antimicrobial activity against several Gram-positive and Gram-negative bacteria, fungi, but were totally inactive against yeasts. Membrane permeabilization assays, only performed with armadillidin H, showed that the peptide is membrane active against bacterial and fungal strains leading to deep changes in cell morphology. This damaging activity visualized by electronic microscopy correlates with a rapid decrease of cell viability leading to highly blebbed cells. In contrast, armadillidin H does not reveal cytotoxicity toward human erythrocytes. Furthermore, no secondary structure could be defined in this study [by circular dichroism (CD) and nuclear magnetic resonance (NMR)] even in a membrane mimicking environment. Therefore, armadillidins represent interesting candidates to gain insight into the biology of glycine-rich AMPs.

  17. Cut-Offs and Response Criteria for the Hospital Universitario La Princesa Index (HUPI) and Their Comparison to Widely-Used Indices of Disease Activity in Rheumatoid Arthritis

    PubMed Central

    Castrejón, Isabel; Ortiz, Ana M.; Toledano, Esther; Castañeda, Santos; García-Vadillo, Alberto; Carmona, Loreto

    2016-01-01

    Objective To estimate cut-off points and to establish response criteria for the Hospital Universitario La Princesa Index (HUPI) in patients with chronic polyarthritis. Methods Two cohorts, one of early arthritis (Princesa Early Arthritis Register Longitudinal [PEARL] study) and other of long-term rheumatoid arthritis (Estudio de la Morbilidad y Expresión Clínica de la Artritis Reumatoide [EMECAR]) including altogether 1200 patients were used to determine cut-off values for remission, and for low, moderate and high activity through receiver operating curve (ROC) analysis. The areas under ROC (AUC) were compared to those of validated indexes (SDAI, CDAI, DAS28). ROC analysis was also applied to establish minimal and relevant clinical improvement for HUPI. Results The best cut-off points for HUPI are 2, 5 and 9, classifying RA activity as remission if ≤2, low disease activity if >2 and ≤5), moderate if >5 and <9 and high if ≥9. HUPI’s AUC to discriminate between low-moderate activity was 0.909 and between moderate-high activity 0.887. DAS28’s AUCs were 0.887 and 0.846, respectively; both indices had higher accuracy than SDAI (AUCs: 0.832 and 0.756) and CDAI (AUCs: 0.789 and 0.728). HUPI discriminates remission better than DAS28-ESR in early arthritis, but similarly to SDAI. The HUPI cut-off for minimal clinical improvement was established at 2 and for relevant clinical improvement at 4. Response criteria were established based on these cut-off values. Conclusions The cut-offs proposed for HUPI perform adequately in patients with either early or long term arthritis. PMID:27603313

  18. Tu Salud, ¡Si Cuenta!: Exposure to a community-wide campaign and its associations with physical activity and fruit and vegetable consumption among individuals of Mexican descent

    PubMed Central

    Reininger, Belinda M.; Mitchell-Bennett, Lisa; Lee, MinJae; Gowen, Rose Z.; Barroso, Cristina S.; Gay, Jennifer L.; Saldana, Mayra Vanessa

    2015-01-01

    Mexican Americans along the US-Mexico border have been found to be disproportionately affected by chronic diseases particularly related to lack of physical activity and healthful food choices. A community-wide campaign (CWC) is an evidence-based strategy to address these behaviors but with few examples of implementation in Mexican descent populations facing profound health disparities. We examined exposure to a CWC, titled Tu Salud ¡Sí Cuenta!, and its association with meeting the recommended minutes of moderate and vigorous physical activity weekly and consuming more portions of fruits and vegetables daily. A cross-sectional sample of 1438 Mexican descent participants was drawn from a city-wide, randomly-selected cohort interviewed between the years 2008 and 2012. Multivariable comparisons of participants exposed and not exposed to the CWC and meeting physical activity guidelines or their fruit and vegetable consumptions using mixed effects models were conducted. The community-wide campaign components included different forms of mass media and individually-focused components such as community health worker (CHW) home visits. After adjusting for gender, age, marital status, educational attainment, language preference, health insurance, and diabetes diagnosis, the strongest association was found between meeting physical activity guidelines and exposure to both CHW discussions and radio messages (adjusted OR=3.83; 95% CI= [1.28, 6.21]; p=0.0099). Participants who reported exposure to both radio and TV messages consumed more portions of fruits and vegetables than those who reported no exposure (adjusted RR=1.30; 95% CI= [1.02, 1.66]; p= 0.0338). This study provides insights into the implementation and behavioral outcomes associated with exposure to a community-wide campaign, a potential model for addressing lifestyle modifications in populations affected by health disparities. PMID:26347959

  19. Tu Salud, ¡Si Cuenta!: Exposure to a community-wide campaign and its associations with physical activity and fruit and vegetable consumption among individuals of Mexican descent.

    PubMed

    Reininger, Belinda M; Mitchell-Bennett, Lisa; Lee, MinJae; Gowen, Rose Z; Barroso, Cristina S; Gay, Jennifer L; Saldana, Mayra Vanessa

    2015-10-01

    Mexican Americans along the US-Mexico border have been found to be disproportionately affected by chronic diseases particularly related to lack of physical activity and healthful food choices. A community-wide campaign (CWC) is an evidence-based strategy to address these behaviors but with few examples of implementation in Mexican descent populations facing profound health disparities. We examined exposure to a CWC, titled Tu Salud ¡Sí Cuenta!, and its association with meeting the recommended minutes of moderate and vigorous physical activity weekly and consuming more portions of fruits and vegetables daily. A cross-sectional sample of 1438 Mexican descent participants was drawn from a city-wide, randomly-selected cohort interviewed between the years 2008 and 2012. Multivariable comparisons of participants exposed and not exposed to the CWC and meeting physical activity guidelines or their fruit and vegetable consumptions using mixed effects models were conducted. The community-wide campaign components included different forms of mass media and individually-focused components such as community health worker (CHW) home visits. After adjusting for gender, age, marital status, educational attainment, language preference, health insurance, and diabetes diagnosis, the strongest association was found between meeting physical activity guidelines and exposure to both CHW discussions and radio messages (adjusted OR = 3.83; 95% CI = [1.28, 6.21]; p = 0.0099). Participants who reported exposure to both radio and TV messages consumed more portions of fruits and vegetables than those who reported no exposure (adjusted RR = 1.30; 95% CI = [1.02, 1.66]; p = 0.0338). This study provides insights into the implementation and behavioral outcomes associated with exposure to a community-wide campaign, a potential model for addressing lifestyle modifications in populations affected by health disparities.

  20. Association of Protein Phosphatase PPM1G With Alcohol Use Disorder and Brain Activity During Behavioral Control in a Genome-Wide Methylation Analysis

    PubMed Central

    Ruggeri, Barbara; Nymberg, Charlotte; Vuoksimaa, Eero; Lourdusamy, Anbarasu; Wong, Cybele P.; Carvalho, Fabiana M.; Jia, Tianye; Cattrell, Anna; Macare, Christine; Banaschewski, Tobias; Barker, Gareth J.; Bokde, Arun L.W.; Bromberg, Uli; Büchel, Christian; Conrod, Patricia J.; Fauth-Bühler, Mira; Flor, Herta; Frouin, Vincent; Gallinat, Jürgen; Garavan, Hugh; Gowland, Penny; Heinz, Andreas; Ittermann, Bernd; Martinot, Jean-Luc; Nees, Frauke; Pausova, Zdenka; Paus, Tomáš; Rietschel, Marcella; Robbins, Trevor; Smolka, Michael N.; Spanagel, Rainer; Bakalkin, Georgy; Mill, Jonathan; Sommer, Wolfgang H.; Rose, Richard J.; Yan, Jia; Aliev, Fazil; Dick, Danielle; Kaprio, Jaakko; Desrivières, Sylvane; Schumann, Gunter

    2016-01-01

    Objective The genetic component of alcohol use disorder is substantial, but monozygotic twin discordance indicates a role for nonheritable differences that could be mediated by epigenetics. Despite growing evidence associating epigenetics and psychiatric disorders, it is unclear how epigenetics, particularly DNA methylation, relate to brain function and behavior, including drinking behavior. Method The authors carried out a genome-wide analysis of DNA methylation of 18 monozygotic twin pairs discordant for alcohol use disorder and validated differentially methylated regions. After validation, the authors characterized these differentially methylated regions using personality trait assessment and functional MRI in a sample of 499 adolescents. Results Hypermethylation in the 3′-protein-phosphatase-1G (PPM1G) gene locus was associated with alcohol use disorder. The authors found association of PPM1G hypermethylation with early escalation of alcohol use and increased impulsiveness. They also observed association of PPM1G hypermethylation with increased blood-oxygen-level-dependent response in the right subthalamic nucleus during an impulsiveness task. Conclusions Overall, the authors provide first evidence for an epigenetic marker associated with alcohol consumption and its underlying neurobehavioral phenotype. PMID:25982659

  1. Electrostatic Assemblies of Well-Dispersed AgNPs on the Surface of Electrospun Nanofibers as Highly Active SERS Substrates for Wide-Range pH Sensing.

    PubMed

    Yang, Tong; Ma, Jun; Zhen, Shu Jun; Huang, Cheng Zhi

    2016-06-15

    Surface-enhanced Raman scattering (SERS) has shown high promise in analysis and bioanalysis, wherein noble metal nanoparticles (NMNPs) such as silver nanoparticles were employed as substrates because of their strong localized surface plasmon resonance (LSPR) properties. However, SERS-based pH sensing was restricted because of the aggregation of NMNPs in acidic medium or biosamples with high ionic strength. Herein, by using the electrostatic interaction as a driving force, AgNPs are assembled on the surface of ethylene imine polymer (PEI)/poly(vinyl alcohol) (PVA) electrospun nanofibers, which are then applied as highly sensitive and reproducible SERS substrate with an enhancement factor (EF) of 10(7)-10(8). When p-aminothiophenol (p-ATP) is used as an indicator with its b2 mode, a good and wide linear response to pH ranging from 2.56 to 11.20 could be available, and the as-prepared nanocomposite fibers then could be fabricated as excellent pH sensors in complicated biological samples such as urine, considering that the pH of urine could reflect the acid-base status of a person. This work not only emerges a cost-effective, direct, and convenient approach to homogeneously decorate AgNPs on the surface of polymer nanofibers but also supplies a route for preparing other noble metal nanofibrous sensing membranes.

  2. High and varying prices for privately insured patients underscore hospital market power.

    PubMed

    White, Chapin; Bond, Amelia M; Reschovsky, James D

    2013-09-01

    Across 13 selected U.S. metropolitan areas, hospital prices for privately insured patients are much higher than Medicare payment rates and vary widely across and within markets, according to a study by the Center for Studying Health System Change (HSC) based on claims data for about 590,000 active and retired nonelderly autoworkers and their dependents. Across the 13 communities, aver­age hospital prices for privately insured patients are about one-and-a-half times Medicare rates for inpatient care and two times what Medicare pays for outpa­tient care. Within individual communities, prices vary widely, with the highest-priced hospital typically paid 60 percent more for inpatient services than the lowest-priced hospital. The price gap within markets is even greater for hospital outpatient care, with the highest-priced hospital typically paid nearly double the lowest-priced hospital. In contrast to the wide variation in hospital prices for pri­vately insured patients across and within markets, prices for primary care physi­cian services generally are close to Medicare rates and vary little within markets. Prices for specialist physician services, however, are higher relative to Medicare and vary more across and within markets. Of the 13 markets, five are in Michigan, which has an unusually concentrated private insurance market, with one insurer commanding a 70-percent market share. Despite the presence of a dominant insurer, almost all Michigan hospi­tals command prices that are higher than Medicare, and some hospitals com­mand prices that are twice what Medicare pays. In the eight markets outside of Michigan, private insurers generally pay even higher hospital prices, with even wider gaps between high- and low-priced hospitals. The variation in hospital and specialist physician prices within communities underscores that some hospitals and physicians have significant market power to command high prices, even in markets with a dominant insurer.

  3. Comparison of glomerular activity patterns by fMRI and wide-field calcium imaging: Implications for principles underlying odor mapping.

    PubMed

    Sanganahalli, Basavaraju G; Rebello, Michelle R; Herman, Peter; Papademetris, Xenophon; Shepherd, Gordon M; Verhagen, Justus V; Hyder, Fahmeed

    2016-02-01

    Functional imaging signals arise from distinct metabolic and hemodynamic events at the neuropil, but how these processes are influenced by pre- and post-synaptic activities need to be understood for quantitative interpretation of stimulus-evoked mapping data. The olfactory bulb (OB) glomeruli, spherical neuropil regions with well-defined neuronal circuitry, can provide insights into this issue. Optical calcium-sensitive fluorescent dye imaging (OICa(2+)) reflects dynamics of pre-synaptic input to glomeruli, whereas high-resolution functional magnetic resonance imaging (fMRI) using deoxyhemoglobin contrast reveals neuropil function within the glomerular layer where both pre- and post-synaptic activities contribute. We imaged odor-specific activity patterns of the dorsal OB in the same anesthetized rats with fMRI and OICa(2+) and then co-registered the respective maps to compare patterns in the same space. Maps by each modality were very reproducible as trial-to-trial patterns for a given odor, overlapping by ~80%. Maps evoked by ethyl butyrate and methyl valerate for a given modality overlapped by ~80%, suggesting activation of similar dorsal glomerular networks by these odors. Comparison of maps generated by both methods for a given odor showed ~70% overlap, indicating similar odor-specific maps by each method. These results suggest that odor-specific glomerular patterns by high-resolution fMRI primarily tracks pre-synaptic input to the OB. Thus combining OICa(2+) and fMRI lays the framework for studies of OB processing over a range of spatiotemporal scales, where OICa(2+) can feature the fast dynamics of dorsal glomerular clusters and fMRI can map the entire glomerular sheet in the OB.

  4. Just how wide should 'wide reading' be?

    PubMed

    Lipscomb, Martin

    2015-10-01

    Educationalists introduce students to literature search strategies that, with rare exceptions, focus chiefly on the location of primary research reports and systematic reviews of those reports. These sources are, however, unlikely to adequately address the normative and/or metaphysical questions that nurses frequently and legitimately interest themselves in. To meet these interests, non-research texts exploring normative and/or metaphysical topics might and perhaps should, in some situations, be deemed suitable search targets. This seems plausible and, moreover, students are encouraged to 'read widely'. Yet accepting this proposition creates significant difficulties. Specifically, if non-research scholarly sources and artistic or literary (humanities) products dealing with normative/metaphysical issues were included in what are, at present, scientifically orientated searches, it is difficult to draw boundaries around what--if anything--is to be excluded. Engaging with this issue highlights problems with qualitative scholarship's designation as 'evidence'. Thus, absurdly, if qualitative scholarship's findings are labelled evidence because they generate practice-relevant understanding/insight, then any literary or artistic artefact (e.g. a throwaway lifestyle magazine) that generates kindred understandings/insights is presumably also evidence? This conclusion is rejected and it is instead proposed that while artistic, literary, and qualitative inquiries can provide practitioners with powerful and stimulating non-evidential understanding, these sources are not evidence as commonly conceived.

  5. Calcium-activated potassium channel SK1 is widely expressed in the peripheral nervous system and sensory organs of adult zebrafish.

    PubMed

    Cabo, R; Zichichi, R; Viña, E; Guerrera, M C; Vázquez, G; García-Suárez, O; Vega, J A; Germanà, A

    2013-10-25

    Sensory cells contain ion channels involved in the organ-specific transduction mechanisms that convert different types of stimuli into electric energy. Here we focus on small-conductance calcium-activated potassium channel 1 (SK1) which plays an important role in all excitable cells acting as feedback regulators in after-hyperpolarization. This study was undertaken to analyze the pattern of expression of SK1 in the zebrafish peripheral nervous system and sensory organs using RT-PRC, Westernblot and immunohistochemistry. Expression of SK1 mRNA was observed at all developmental stages analyzed (from 10 to 100 days post fertilization, dpf), and the antibody used identified a protein with a molecular weight of 70kDa, at 100dpf (regarded to be adult). Cell expressing SK1 in adult animals were neurons of dorsal root and cranial nerve sensory ganglia, sympathetic neurons, sensory cells in neuromasts of the lateral line system and taste buds, crypt olfactory neurons and photoreceptors. Present results report for the first time the expression and the distribution of SK1 in the peripheral nervous system and sensory organs of adult zebrafish, and may contribute to set zebrafish as an interesting experimental model for calcium-activated potassium channels research. Moreover these findings are of potential interest because the potential role of SK as targets for the treatment of neurological diseases and sensory disorders.

  6. Genome-wide analysis of EgEVE_1, a transcriptionally active endogenous viral element associated to small RNAs in Eucalyptus genomes.

    PubMed

    Marcon, Helena Sanches; Costa-Silva, Juliana; Lorenzetti, Alan Péricles Rodrigues; Marino, Celso Luis; Domingues, Douglas Silva

    2017-02-23

    Endogenous viral elements (EVEs) are the result of heritable horizontal gene transfer from viruses to hosts. In the last years, several EVE integration events were reported in plants by the exponential availability of sequenced genomes. Eucalyptus grandis is a forest tree species with a sequenced genome that is poorly studied in terms of evolution and mobile genetic elements composition. Here we report the characterization of E. grandis endogenous viral element 1 (EgEVE_1), a transcriptionally active EVE with a size of 5,664 bp. Phylogenetic analysis and genomic distribution demonstrated that EgEVE_1 is a newly described member of the Caulimoviridae family, distinct from the recently characterized plant Florendoviruses. Genomic distribution of EgEVE_1 and Florendovirus is also distinct. EgEVE_1 qPCR quantification in Eucalyptus urophylla suggests that this genome has more EgEVE_1 copies than E. grandis. EgEVE_1 transcriptional activity was demonstrated by RT-qPCR in five Eucalyptus species and one intrageneric hybrid. We also identified that Eucalyptus EVEs can generate small RNAs (sRNAs),that might be involved in de novo DNA methylation and virus resistance. Our data suggest that EVE families in Eucalyptus have distinct properties, and we provide the first comparative analysis of EVEs in Eucalyptus genomes.

  7. Development of a modified independent parallel reactions kinetic model and comparison with the distributed activation energy model for the pyrolysis of a wide variety of biomass fuels.

    PubMed

    Sfakiotakis, Stelios; Vamvuka, Despina

    2015-12-01

    The pyrolysis of six waste biomass samples was studied and the fuels were kinetically evaluated. A modified independent parallel reactions scheme (IPR) and a distributed activation energy model (DAEM) were developed and their validity was assessed and compared by checking their accuracy of fitting the experimental results, as well as their prediction capability in different experimental conditions. The pyrolysis experiments were carried out in a thermogravimetric analyzer and a fitting procedure, based on least squares minimization, was performed simultaneously at different experimental conditions. A modification of the IPR model, considering dependence of the pre-exponential factor on heating rate, was proved to give better fit results for the same number of tuned kinetic parameters, comparing to the known IPR model and very good prediction results for stepwise experiments. Fit of calculated data to the experimental ones using the developed DAEM model was also proved to be very good.

  8. Dermatophyte susceptibility varies towards antimicrobial textiles.

    PubMed

    Hammer, Timo R; Mucha, Helmut; Hoefer, Dirk

    2012-07-01

    Dermatophytoses are a widespread problem worldwide. Textiles in contact with infected skin can serve as a carrier for fungus propagation. Hitherto, it is unknown, whether antifungal textiles could contribute in controlling dermatophytes e.g. by disrupting the chain of infection. Testing of antimicrobial fabrics for their antifungal activities therefore is a fundamental prerequisite to assess the putative clinical relevance of textiles for dermatophyte prevention. Fabrics finished with either didecyldimethylammonium chloride (DDAC), poly-hexamethylenbiguanide, copper and two silver chloride concentrations were tested for their antifungal activity against Trichophyton rubrum, Trichophyton mentagrophytes and Candida albicans. To prove dermatophyte susceptibility towards the textiles, swatches were subjected to DIN EN 14199 (Trichophyton sp.) or DIN EN ISO 20743 (C. albicans) respectively. In addition, samples were embedded, and semi-thin sections were analysed microscopically. While all samples showed a clear inhibition of C. albicans, activity against Trichophyton sp. varied significantly: For example, DDAC completely inhibited T. rubrum growth, whereas T. mentagrophytes growth remained unaffected even in direct contact to the fibres. The results favour to add T. mentagrophytes as a test organism in textile dermatophyte efficacy tests. Microscopic analysis of swatches allowed detailed evaluation of additional parameters like mycelium thickness, density and hyphae penetration depth into the fabric.

  9. Genome-wide analysis of short interspersed nuclear elements SINES revealed high sequence conservation, gene association and retrotranspositional activity in wheat

    PubMed Central

    Ben-David, Smadar; Yaakov, Beery; Kashkush, Khalil

    2013-01-01

    Short interspersed nuclear elements (SINEs) are non-autonomous non-LTR retroelements that are present in most eukaryotic species. While SINEs have been intensively investigated in humans and other animal systems, they are poorly studied in plants, especially in wheat (Triticum aestivum). We used quantitative PCR of various wheat species to determine the copy number of a wheat SINE family, termed Au SINE, combined with computer-assisted analyses of the publicly available 454 pyrosequencing database of T. aestivum. In addition, we utilized site-specific PCR on 57 Au SINE insertions, transposon methylation display and transposon display on newly formed wheat polyploids to assess retrotranspositional activity, epigenetic status and genetic rearrangements in Au SINE, respectively. We retrieved 3706 different insertions of Au SINE from the 454 pyrosequencing database of T. aestivum, and found that most of the elements are inserted in A/T-rich regions, while approximately 38% of the insertions are associated with transcribed regions, including known wheat genes. We observed typical retrotransposition of Au SINE in the second generation of a newly formed wheat allohexaploid, and massive hypermethylation in CCGG sites surrounding Au SINE in the third generation. Finally, we observed huge differences in the copy numbers in diploid Triticum and Aegilops species, and a significant increase in the copy numbers in natural wheat polyploids, but no significant increase in the copy number of Au SINE in the first four generations for two of three newly formed allopolyploid species used in this study. Our data indicate that SINEs may play a prominent role in the genomic evolution of wheat through stress-induced activation. PMID:23855320

  10. Genome-Wide Identification, 3D Modeling, Expression and Enzymatic Activity Analysis of Cell Wall Invertase Gene Family from Cassava (Manihot esculenta Crantz)

    PubMed Central

    Yao, Yuan; Geng, Meng-Ting; Wu, Xiao-Hui; Liu, Jiao; Li, Rui-Mei; Hu, Xin-Wen; Guo, Jian-Chun

    2014-01-01

    The cell wall invertases play a crucial role on the sucrose metabolism in plant source and sink organs. In this research, six cell wall invertase genes (MeCWINV1-6) were cloned from cassava. All the MeCWINVs contain a putative signal peptide with a predicted extracellular location. The overall predicted structures of the MeCWINV1-6 are similar to AtcwINV1. Their N-terminus domain forms a β-propeller module and three conserved sequence domains (NDPNG, RDP and WECP(V)D), in which the catalytic residues are situated in these domains; while the C-terminus domain consists of a β-sandwich module. The predicted structure of Pro residue from the WECPD (MeCWINV1, 2, 5, and 6), and Val residue from the WECVD (MeCWINV3 and 4) are different. The activity of MeCWINV1 and 3 were higher than other MeCWINVs in leaves and tubers, which suggested that sucrose was mainly catalyzed by the MeCWINV1 and 3 in the apoplastic space of cassava source and sink organs. The transcriptional levels of all the MeCWINVs and their enzymatic activity were lower in tubers than in leaves at all the stages during the cassava tuber development. It suggested that the major role of the MeCWINVs was on the regulation of carbon exportation from source leaves, and the ratio of sucrose to hexose in the apoplasts; the role of these enzymes on the sucrose unloading to tuber was weaker. PMID:24786092

  11. Genome-wide identification, 3D modeling, expression and enzymatic activity analysis of cell wall invertase gene family from cassava (Manihot esculenta Crantz).

    PubMed

    Yao, Yuan; Geng, Meng-Ting; Wu, Xiao-Hui; Liu, Jiao; Li, Rui-Mei; Hu, Xin-Wen; Guo, Jian-Chun

    2014-04-28

    The cell wall invertases play a crucial role on the sucrose metabolism in plant source and sink organs. In this research, six cell wall invertase genes (MeCWINV1-6) were cloned from cassava. All the MeCWINVs contain a putative signal peptide with a predicted extracellular location. The overall predicted structures of the MeCWINV1-6 are similar to AtcwINV1. Their N-terminus domain forms a β-propeller module and three conserved sequence domains (NDPNG, RDP and WECP(V)D), in which the catalytic residues are situated in these domains; while the C-terminus domain consists of a β-sandwich module. The predicted structure of Pro residue from the WECPD (MeCWINV1, 2, 5, and 6), and Val residue from the WECVD (MeCWINV3 and 4) are different. The activity of MeCWINV1 and 3 were higher than other MeCWINVs in leaves and tubers, which suggested that sucrose was mainly catalyzed by the MeCWINV1 and 3 in the apoplastic space of cassava source and sink organs. The transcriptional levels of all the MeCWINVs and their enzymatic activity were lower in tubers than in leaves at all the stages during the cassava tuber development. It suggested that the major role of the MeCWINVs was on the regulation of carbon exportation from source leaves, and the ratio of sucrose to hexose in the apoplasts; the role of these enzymes on the sucrose unloading to tuber was weaker.

  12. Four different types of protease-activated receptors are widely expressed in the brain and are up-regulated in hippocampus by severe ischemia.

    PubMed

    Striggow, F; Riek-Burchardt, M; Kiesel, A; Schmidt, W; Henrich-Noack, P; Breder, J; Krug, M; Reymann, K G; Reiser, G

    2001-08-01

    A variety of extracellular serine proteases are expressed in the central nervous system or might permeate the blood-brain barrier under pathological conditions. However, their intracerebral targets and physiological functions are largely unknown. Here, we show that four distinct subtypes of protease-activated receptors (PARs) are abundantly expressed in the adult rat brain and in organotypic hippocampal slice cultures. PAR-1 expression was significant in the hippocampus, cortex and amygdala. Highest densities of PAR-2 and PAR-3 were observed in hippocampus, cortex, amygdala, thalamus, hypothalamus and striatum. Apart from the striatum, a similar localization was found for PAR-4. Within the hippocampal formation, each PAR subtype was predominantly localized in the pyramidal cell layers. Additionally, we identified PAR-2 in mossy fibers between dentate gyrus and CA3, PAR-3 in the subiculum and PAR-4 in CA3 and in mossy fibres as well as in the stratum lacunosum moleculare. After exposing hippocampal slice cultures to a severe experimental ischemia (oxygen-glucose deprivation), the expression of PARs 1-3 was up-regulated with subtype-specific kinetics. The localization of PARs in brain regions particularly vulnerable to ischemic insults as well as distinct alterations in the expression pattern after experimental ischemia support the notion of an important role of extracellular serine proteases and PARs in cerebral ischemia.

  13. Genome-Wide Survey and Expression Profile Analysis of the Mitogen-Activated Protein Kinase (MAPK) Gene Family in Brassica rapa.

    PubMed

    Lu, Kun; Guo, Wenjin; Lu, Junxing; Yu, Hao; Qu, Cunmin; Tang, Zhanglin; Li, Jiana; Chai, Yourong; Liang, Ying

    2015-01-01

    Mitogen-activated protein kinase (MAPK) cascades are fundamental signal transduction modules in plants, controlling cell division, development, hormone signaling, and biotic and abiotic stress responses. Although MAPKs have been investigated in several plant species, a comprehensive analysis of the MAPK gene family has hitherto not been performed in Brassica rapa. In this study, we identified 32 MAPKs in the B. rapa genome by conducting BLASTP and syntenic block analyses, and screening for the essential signature motif (TDY or TEY) of plant MAPK proteins. Of the 32 BraMAPK genes retrieved from the Brassica Database, 13 exhibited exon splicing errors, excessive splicing of the 5' sequence, excessive retention of the 5' sequence, and sequencing errors of the 3' end. Phylogenetic trees of the 32 corrected MAPKs from B. rapa and of MAPKs from other plants generated by the neighbor-joining and maximum likelihood methods suggested that BraMAPKs could be divided into four groups (groups A, B, C, and D). Gene number expansion was observed for BraMAPK genes in groups A and D, which may have been caused by the tandem duplication and genome triplication of the ancestral genome of the Brassica progenitor. Except for five members of the BraMAPK10 subfamily, the identified BraMAPKs were expressed in most of the tissues examined, including callus, root, stem, leaf, flower, and silique. Quantitative real-time PCR demonstrated that at least six and five BraMAPKs were induced or repressed by various abiotic stresses and hormone treatments, respectively, suggesting their potential roles in the abiotic stress response and various hormone signal transduction pathways in B. rapa. This study provides valuable insight into the putative physiological and biochemical functions of MAPK genes in B. rapa.

  14. Genome-Wide Identification, Evolution, and Co-expression Network Analysis of Mitogen-Activated Protein Kinase Kinase Kinases in Brachypodium distachyon

    PubMed Central

    Feng, Kewei; Liu, Fuyan; Zou, Jinwei; Xing, Guangwei; Deng, Pingchuan; Song, Weining; Tong, Wei; Nie, Xiaojun

    2016-01-01

    Mitogen-activated protein kinase (MAPK) cascades are the conserved and universal signal transduction modules in all eukaryotes, which play the vital roles in plant growth, development, and in response to multiple stresses. In this study, we used bioinformatics methods to identify 86 MAPKKK protein encoded by 73 MAPKKK genes in Brachypodium. Phylogenetic analysis of MAPKKK family from Arabidopsis, rice, and Brachypodium has classified them into three subfamilies, of which 28 belonged to MEKK, 52 to Raf, and 6 to ZIK subfamily, respectively. Conserved protein motif, exon-intron organization, and splicing intron phase in kinase domains supported the evolutionary relationships inferred from the phylogenetic analysis. And gene duplication analysis suggested the chromosomal segment duplication happened before the divergence of the rice and Brachypodium, while all of three tandem duplicated gene pairs happened after their divergence. We further demonstrated that the MAPKKKs have evolved under strong purifying selection, implying the conservation of them. The splicing transcripts expression analysis showed that the splicesome translating longest protein tended to be adopted. Furthermore, the expression analysis of BdMAPKKKs in different organs and development stages as well as heat, virus and drought stresses revealed that the MAPKKK genes were involved in various signaling pathways. And the circadian analysis suggested there were 41 MAPKKK genes in Brachypodium showing cycled expression in at least one condition, of which seven MAPKKK genes expressed in all conditions and the promoter analysis indicated these genes possessed many cis-acting regulatory elements involved in circadian and light response. Finally, the co-expression network of MAPK, MAPKK, and MAPKKK in Brachypodium was constructed using 144 microarray and RNA-seq datasets, and ten potential MAPK cascades pathway were predicted. To conclude, our study provided the important information for evolutionary and

  15. Genome-Wide Survey and Expression Profile Analysis of the Mitogen-Activated Protein Kinase (MAPK) Gene Family in Brassica rapa

    PubMed Central

    Yu, Hao; Qu, Cunmin; Tang, Zhanglin; Li, Jiana; Chai, Yourong; Liang, Ying

    2015-01-01

    Mitogen-activated protein kinase (MAPK) cascades are fundamental signal transduction modules in plants, controlling cell division, development, hormone signaling, and biotic and abiotic stress responses. Although MAPKs have been investigated in several plant species, a comprehensive analysis of the MAPK gene family has hitherto not been performed in Brassica rapa. In this study, we identified 32 MAPKs in the B. rapa genome by conducting BLASTP and syntenic block analyses, and screening for the essential signature motif (TDY or TEY) of plant MAPK proteins. Of the 32 BraMAPK genes retrieved from the Brassica Database, 13 exhibited exon splicing errors, excessive splicing of the 5' sequence, excessive retention of the 5' sequence, and sequencing errors of the 3' end. Phylogenetic trees of the 32 corrected MAPKs from B. rapa and of MAPKs from other plants generated by the neighbor-joining and maximum likelihood methods suggested that BraMAPKs could be divided into four groups (groups A, B, C, and D). Gene number expansion was observed for BraMAPK genes in groups A and D, which may have been caused by the tandem duplication and genome triplication of the ancestral genome of the Brassica progenitor. Except for five members of the BraMAPK10 subfamily, the identified BraMAPKs were expressed in most of the tissues examined, including callus, root, stem, leaf, flower, and silique. Quantitative real-time PCR demonstrated that at least six and five BraMAPKs were induced or repressed by various abiotic stresses and hormone treatments, respectively, suggesting their potential roles in the abiotic stress response and various hormone signal transduction pathways in B. rapa. This study provides valuable insight into the putative physiological and biochemical functions of MAPK genes in B. rapa. PMID:26173020

  16. Evidence for wide-spread active galactic nucleus-driven outflows in the most massive z ∼ 1-2 star-forming galaxies

    SciTech Connect

    Genzel, R.; Förster Schreiber, N. M.; Rosario, D.; Lang, P.; Lutz, D.; Wisnioski, E.; Wuyts, E.; Wuyts, S.; Bandara, K.; Bender, R.; Berta, S.; Kurk, J.; Mendel, J. T.; Tacconi, L. J.; Wilman, D.; Beifiori, A.; Burkert, A.; Buschkamp, P.; Chan, J.; Brammer, G. E-mail: genzel@mpe.mpg.de; and others

    2014-11-20

    In this paper, we follow up on our previous detection of nuclear ionized outflows in the most massive (log(M {sub *}/M {sub ☉}) ≥ 10.9) z ∼ 1-3 star-forming galaxies by increasing the sample size by a factor of six (to 44 galaxies above log(M {sub *}/M {sub ☉}) ≥ 10.9) from a combination of the SINS/zC-SINF, LUCI, GNIRS, and KMOS{sup 3D}spectroscopic surveys. We find a fairly sharp onset of the incidence of broad nuclear emission (FWHM in the Hα, [N II], and [S II] lines ∼450-5300 km s{sup –1}), with large [N II]/Hα ratios, above log(M {sub *}/M {sub ☉}) ∼ 10.9, with about two-thirds of the galaxies in this mass range exhibiting this component. Broad nuclear components near and above the Schechter mass are similarly prevalent above and below the main sequence of star-forming galaxies, and at z ∼ 1 and ∼2. The line ratios of the nuclear component are fit by excitation from active galactic nuclei (AGNs), or by a combination of shocks and photoionization. The incidence of the most massive galaxies with broad nuclear components is at least as large as that of AGNs identified by X-ray, optical, infrared, or radio indicators. The mass loading of the nuclear outflows is near unity. Our findings provide compelling evidence for powerful, high-duty cycle, AGN-driven outflows near the Schechter mass, and acting across the peak of cosmic galaxy formation.

  17. Summary of nuclear fuel reprocessing activities around the world

    SciTech Connect

    Mellinger, P.J.; Harmon, K.M.; Lakey, L.T.

    1984-11-01

    This review of international practices for nuclear fuel reprocessing was prepared to provide a nontechnical summary of the current status of nuclear fuel reprocessing activities around the world. The sources of information are widely varied.

  18. Does the Newtonian Gravity "Constant" G Vary?

    NASA Astrophysics Data System (ADS)

    Noerdlinger, Peter D.

    2015-08-01

    A series of measurements of Newton's gravity constant, G, dating back as far as 1893, yielded widely varying values, the variation greatly exceeding the stated error estimates (Gillies, 1997; Quinn, 2000, Mohr et al 2008). The value of G is usually said to be unrelated to other physics, but we point out that the 8B Solar Neutrino Rate ought to be very sensitive. Improved pulsar timing could also help settle the issue as to whether G really varies. We claim that the variation in measured values over time (1893-2014 C.E.) is a more serious problem than the failure of the error bars to overlap; it appears that challenging or adjusting the error bars hardly masks the underlying disagreement in central values. We have assessed whether variations in the gravitational potential due to (for example) local dark matter (DM) could explain the variations. We find that the required potential fluctuations could transiently accelerate the Solar System and nearby stars to speeds in excess of the Galactic escape speed. Previous theories for the variation in G generally deal with supposed secular variation on a cosmological timescale, or very rapid oscillations whose envelope changes on that scale (Steinhardt and Will 1995). Therefore, these analyses fail to support variations on the timescale of years or spatial scales of order parsecs, which would be required by the data for G. We note that true variations in G would be associated with variations in clock rates (Derevianko and Pospelov 2014; Loeb and Maoz 2015), which could mask changes in orbital dynamics. Geringer-Sameth et al (2014) studied γ-ray emission from the nearby Reticulum dwarf galaxy, which is expected to be free of "ordinary" (stellar, black hole) γ-ray sources and found evidence for DM decay. Bernabei et al (2003) also found evidence for DM penetrating deep underground at Gran Sasso. If, indeed, variations in G can be tied to variations in gravitational potential, we have a new tool to assess the DM density.

  19. Model predictive control for tracking randomly varying references

    NASA Astrophysics Data System (ADS)

    Falugi, Paola

    2015-04-01

    This paper proposes a model predictive control scheme for tracking a-priori unknown references varying in a wide range and analyses its performance. It is usual to assume that the reference eventually converges to a constant in which case convergence to zero of the tracking error can be established. In this note we remove this simplifying assumption and characterise the set to which the tracking error converges and the associated region of convergence.

  20. Genome Wide Association Studies

    NASA Astrophysics Data System (ADS)

    Sebastiani, Paola; Solovieff, Nadia

    The availability of high throughput technology for parallel genotyping has opened the field of genetics to genome-wide association studies (GWAS). These studies generate massive amount of genetic data that challenge investigators with issues related to data management, statistical analysis of large data sets, visualization, and annotation of results. We will review the common approach to analysis of GWAS data and then discuss options to learn more from these data.

  1. The wide-range ejector flowmeter: calibrated gas evacuation comprising both high and low gas flows.

    PubMed

    Waaben, J; Brinkløv, M M; Jørgensen, S

    1984-11-01

    The wide-range ejector flowmeter is an active scavenging system applying calibrated gas removal directly to the anaesthetic circuit. The evacuation rate can be adjusted on the flowmeter under visual control using the calibration scale ranging from 200 ml X min-1 to 151 X min-1. The accuracy of the calibration was tested on three ejector flowmeters at 12 different presettings. The percentage deviation from presetting varied from + 18 to - 19.4 per cent. The ejector flowmeter enables the provision of consistent and accurately calibrated extraction of waste gases and is applicable within a wide range of fresh gas flows.

  2. Innovation in Science Education - World-Wide.

    ERIC Educational Resources Information Center

    Baez, Albert V.

    The purpose of this book is to promote improvements in science education, world-wide, but particularly in developing countries. It is addressed to those in positions to make effective contributions to the improvement of science education. The world-wide role of science education, the goals of innovative activities, past experience in efforts to…

  3. A genome-wide siRNA screen for regulators of tumor suppressor p53 activity in human non-small lung cancer cells identifies components of the RNA splicing machinery as targets for anticancer treatment.

    PubMed

    Siebring-van Olst, Ellen; Blijlevens, Maxime; de Menezes, Renee X; van der Meulen-Muileman, Ida H; Smit, Egbert F; van Beusechem, Victor W

    2017-03-13

    Reinstating wild-type tumor suppressor p53 activity could be a valuable option for the treatment of cancer. To contribute to development of new treatment options for non-small cell lung cancer (NSCLC), we performed genome-wide siRNA screens for determinants of p53 activity in NSCLC cells. We identified many genes not previously known to be involved in regulating p53 activity. Silencing p53 pathway inhibitor genes was associated with loss of cell viability. The largest functional gene cluster influencing p53 activity was mRNA splicing. Prominent p53 activation was observed upon silencing of specific spliceosome components, rather than by general inhibition of the spliceosome. Ten genes were validated as inhibitors of p53 activity in multiple NSCLC cell lines: genes encoding the Ras-pathway activator SOS1, the zinc finger protein TSHZ3, the mitochondrial membrane protein COX16 and the spliceosome components SNRPD3, SF3A3, SF3B1, SF3B6, XAB2, CWC22 and HNRNPL. Silencing these genes generally increased p53 levels, with distinct effects on CDKN1A expression, induction of cell cycle arrest and cell death. Silencing spliceosome components was associated with alternative splicing of MDM4 mRNA, which could contribute to activation of p53. In addition, silencing splice factors was particularly effective in killing NSCLC cells, albeit in a p53-independent manner. Interestingly, silencing SNRPD3 and SF3A3 exerted much stronger cytotoxicity to NSCLC cells than to lung fibroblasts, suggesting that these genes could represent useful therapeutic targets. This article is protected by copyright. All rights reserved.

  4. Varying electric charge in multiscale spacetimes

    NASA Astrophysics Data System (ADS)

    Calcagni, Gianluca; Magueijo, João; Fernández, David Rodríguez

    2014-01-01

    We derive the covariant equations of motion for Maxwell field theory and electrodynamics in multiscale spacetimes with weighted Laplacian. An effective spacetime-dependent electric charge of geometric origin naturally emerges from the theory, thus giving rise to a varying fine-structure constant. The theory is compared with other varying-coupling models, such as those with a varying electric charge or varying speed of light. The theory is also confronted with cosmological observations, which can place constraints on the characteristic scales in the multifractional measure. We note that the model considered here is fundamentally different from those previously proposed in the literature, either of the varying-e or varying-c persuasion.

  5. The time-course of hindbrain neuronal activity varies according to location during either intraperitoneal or subcutaneous tumor growth in rats: single Fos and dual Fos/dopamine β-hydroxylase immunohistochemistry.

    PubMed

    Lackovicova, Lubica; Gaykema, Ronald P; Banovska, Lucia; Kiss, Alexander; Goehler, Lisa E; Mravec, Boris

    2013-07-15

    Neuronal activity in the nucleus of the solitary tract, ventrolateral medulla, area postrema, and parabrachial nucleus was studied in rats with intraperitoneal or subcutaneous tumors on the 7th, 14th, 21st, and 28th day after injection of fibrosarcoma tumor cells. We found that the number of Fos and dopamine β-hydroxylase immunopositive neurons differs between animals with intraperitoneal and subcutaneous tumors and also between tumor-bearing rats at different times following injection. Our data indicate that responses of the brainstem structures to peripheral tumor growth depend on the localization as well as the stage of the tumor growth.

  6. Wide Angle Movie

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This brief movie illustrates the passage of the Moon through the Saturn-bound Cassini spacecraft's wide-angle camera field of view as the spacecraft passed by the Moon on the way to its closest approach with Earth on August 17, 1999. From beginning to end of the sequence, 25 wide-angle images (with a spatial image scale of about 14 miles per pixel (about 23 kilometers)were taken over the course of 7 and 1/2 minutes through a series of narrow and broadband spectral filters and polarizers, ranging from the violet to the near-infrared regions of the spectrum, to calibrate the spectral response of the wide-angle camera. The exposure times range from 5 milliseconds to 1.5 seconds. Two of the exposures were smeared and have been discarded and replaced with nearby images to make a smooth movie sequence. All images were scaled so that the brightness of Crisium basin, the dark circular region in the upper right, is approximately the same in every image. The imaging data were processed and released by the Cassini Imaging Central Laboratory for Operations (CICLOPS)at the University of Arizona's Lunar and Planetary Laboratory, Tucson, AZ.

    Photo Credit: NASA/JPL/Cassini Imaging Team/University of Arizona

    Cassini, launched in 1997, is a joint mission of NASA, the European Space Agency and Italian Space Agency. The mission is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  7. Single-index varying coefficient model for functional responses.

    PubMed

    Luo, Xinchao; Zhu, Lixing; Zhu, Hongtu

    2016-12-01

    Recently, massive functional data have been widely collected over space across a set of grid points in various imaging studies. It is interesting to correlate functional data with various clinical variables, such as age and gender, in order to address scientific questions of interest. The aim of this article is to develop a single-index varying coefficient (SIVC) model for establishing a varying association between functional responses (e.g., image) and a set of covariates. It enjoys several unique features of both varying-coefficient and single-index models. An estimation procedure is developed to estimate varying coefficient functions, the index function, and the covariance function of individual functions. The optimal integration of information across different grid points is systematically delineated and the asymptotic properties (e.g., consistency and convergence rate) of all estimators are examined. Simulation studies are conducted to assess the finite-sample performance of the proposed estimation procedure. Furthermore, our real data analysis of a white matter tract dataset obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study confirms the advantage and accuracy of SIVC model over the popular varying coefficient model.

  8. Nonlinear Varying Coefficient Models with Applications to Studying Photosynthesis

    PubMed Central

    Kürüm, Esra; Li, Runze; Wang, Yang; ŞEntürk, Damla

    2014-01-01

    Motivated by a study on factors affecting the level of photosynthetic activity in a natural ecosystem, we propose nonlinear varying coefficient models, in which the relationship between the predictors and the response variable is allowed to be nonlinear. One-step local linear estimators are developed for the nonlinear varying coefficient models and their asymptotic normality is established leading to point-wise asymptotic confidence bands for the coefficient functions. Two-step local linear estimators are also proposed for cases where the varying coefficient functions admit different degrees of smoothness; bootstrap confidence intervals are utilized for inference based on the two-step estimators. We further propose a generalized F test to study whether the coefficient functions vary over a covariate. We illustrate the proposed methodology via an application to an ecology data set and study the finite sample performance by Monte Carlo simulation studies. PMID:24976756

  9. Nonlinear Varying Coefficient Models with Applications to Studying Photosynthesis.

    PubMed

    Kürüm, Esra; Li, Runze; Wang, Yang; SEntürk, Damla

    2014-03-01

    Motivated by a study on factors affecting the level of photosynthetic activity in a natural ecosystem, we propose nonlinear varying coefficient models, in which the relationship between the predictors and the response variable is allowed to be nonlinear. One-step local linear estimators are developed for the nonlinear varying coefficient models and their asymptotic normality is established leading to point-wise asymptotic confidence bands for the coefficient functions. Two-step local linear estimators are also proposed for cases where the varying coefficient functions admit different degrees of smoothness; bootstrap confidence intervals are utilized for inference based on the two-step estimators. We further propose a generalized F test to study whether the coefficient functions vary over a covariate. We illustrate the proposed methodology via an application to an ecology data set and study the finite sample performance by Monte Carlo simulation studies.

  10. Fractal analysis of time varying data

    DOEpatents

    Vo-Dinh, Tuan; Sadana, Ajit

    2002-01-01

    Characteristics of time varying data, such as an electrical signal, are analyzed by converting the data from a temporal domain into a spatial domain pattern. Fractal analysis is performed on the spatial domain pattern, thereby producing a fractal dimension D.sub.F. The fractal dimension indicates the regularity of the time varying data.

  11. Novel shock absorber features varying yield strengths

    NASA Technical Reports Server (NTRS)

    Geier, D. J.

    1964-01-01

    A shock absorbent webbing of partially drawn synthetic strands is arranged in sections of varying density related to the varying mass of the human body. This is contoured to protect the body at points of contact, when subjected to large acceleration or deceleration forces.

  12. Wide Band Artificial Pulsar

    NASA Astrophysics Data System (ADS)

    Parsons, Zackary

    2017-01-01

    The Wide Band Artificial Pulsar (WBAP) is an instrument verification device designed and built by the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virgina. The site currently operates the Green Bank Ultimate Pulsar Processing Instrument (GUPPI) and the Versatile Green Bank Astronomical Spectrometer (VEGAS) digital backends for their radio telescopes. The commissioning and continued support for these sophisticated backends has demonstrated a need for a device capable of producing an accurate artificial pulsar signal. The WBAP is designed to provide a very close approximation to an actual pulsar signal. This presentation is intended to provide an overview of the current hardware and software implementations and to also share the current results from testing using the WBAP.

  13. Wide spectral band beam analysis

    NASA Astrophysics Data System (ADS)

    Aharon, Oren

    2015-03-01

    The reality in laser beam profiling is that measurements are performed over a wide spectrum of wavelengths and power ranges. Many applications use multiple laser wavelengths with very different power levels, a fact which dictates a need for a better measuring tool. Rapid progress in the fiber laser area has increased the demand for lasers in the wavelength range of 900 - 1030 nm, while the telecommunication market has increased the demand for wavelength range of 1300nm - 1600 nm, on the other hand the silicone chip manufacturing and mass production requirements tend to lower the laser wavelength towards the 190nm region. In many cases there is a need to combine several lasers together in order to perform a specific task. A typical application is to combine one visible laser for pointing, with a different laser for material processing with a very different wavelength and power level. The visible laser enables accurate pointing before the second laser is operated. The beam profile of the intensity distribution is an important parameter that indicates how a laser beam will behave in an application. Currently a lab, where many different lasers are used, will find itself using various laser beam profilers from several vendors with different specifications and accuracies. It is the propose of this article to present a technological breakthrough in the area of detectors, electronics and optics allowing intricate measurements of lasers with different wavelength and with power levels that vary many orders of magnitude by a single beam profiler.

  14. Organic particulate matter formation at varying relative humidity using surrogate secondary and primary organic compounds with activity corrections in the condensed phase obtained using a method based on the Wilson equation

    NASA Astrophysics Data System (ADS)

    Chang, E. I.; Pankow, J. F.

    2010-06-01

    Secondary organic aerosol (SOA) formation in the atmosphere is currently often modeled using a multiple lumped "two-product" (N·2p) approach. The N·2p approach neglects: 1) variation of activity coefficient (ζi) values and mean molecular weight MW in the particulate matter (PM) phase; 2) water uptake into the PM; and 3) the possibility of phase separation in the PM. This study considers these effects by adopting an (N·2p)ζpMW,ζ approach (θ is a phase index). Specific chemical structures are assigned to 25 lumped SOA compounds and to 15 representative primary organic aerosol (POA) compounds to allow calculation of ζi and MW values. The SOA structure assignments are based on chamber-derived 2p gas/particle partition coefficient values coupled with known effects of structure on vapor pressure pL,io (atm). To facilitate adoption of the (N·2p)ζpMW,θ approach in large-scale models, this study also develops CP-Wilson.1 (Chang-Pankow-Wilson.1), a group-contribution ζi-prediction method that is more computationally economical than the UNIFAC model of Fredenslund et al. (1975). Group parameter values required by CP-Wilson.1 are obtained by fitting ζi values to predictions from UNIFAC. The (N·2p)ζpMW,θ approach is applied (using CP-Wilson.1) to several real α-pinene/O3 chamber cases for high reacted hydrocarbon levels (ΔHC≈400 to 1000 μg m-3) when relative humidity (RH) ≍50%. Good agreement between the chamber and predicted results is obtained using both the (N·2p)ζpMW,θ and N·2p approaches, indicating relatively small water effects under these conditions. However, for a hypothetical α-pinene/O3 case at ΔHC=30 μg m-3 and

  15. Dynamic Factor Analysis Models With Time-Varying Parameters.

    PubMed

    Chow, Sy-Miin; Zu, Jiyun; Shifren, Kim; Zhang, Guangjian

    2011-04-11

    Dynamic factor analysis models with time-varying parameters offer a valuable tool for evaluating multivariate time series data with time-varying dynamics and/or measurement properties. We use the Dynamic Model of Activation proposed by Zautra and colleagues (Zautra, Potter, & Reich, 1997) as a motivating example to construct a dynamic factor model with vector autoregressive relations and time-varying cross-regression parameters at the factor level. Using techniques drawn from the state-space literature, the model was fitted to a set of daily affect data (over 71 days) from 10 participants who had been diagnosed with Parkinson's disease. Our empirical results lend partial support and some potential refinement to the Dynamic Model of Activation with regard to how the time dependencies between positive and negative affects change over time. A simulation study is conducted to examine the performance of the proposed techniques when (a) changes in the time-varying parameters are represented using the true model of change, (b) supposedly time-invariant parameters are represented as time-varying, and

  16. Hemolymph drop impact outcomes on surfaces with varying wettability

    NASA Astrophysics Data System (ADS)

    Milionis, Athanasios; Ghokulla Krishnan, K.; Loth, Eric

    2015-08-01

    Insect fouling from coagulated hemolymph and exoskeleton parts is a major challenge in the aerospace industry for the next generation of aerodynamic surfaces, which will employ laminar flow that requires extremely smooth surfaces. However, the wetting physics and dynamics of hemolymph (insect blood) on surfaces are not well understood. The present study seeks to gain a fundamental insight on the effect of surface wetting characteristics and dynamics resulting from a hemolymph drop impact, the first such study. In particular, hemolymph drops extracted from Acheta domesticus were dispensed from a range of heights to vary the kinetic impact on surfaces, which had widely varying water wetting behavior (from superhydrophilic to superhydrophobic). The impact dynamics were investigated with high-speed imaging while the dried residues were studied with optical microscopy. It was found that a superhydrophobic surface (based on thermoplastic with silica nano-particles) was able to significantly reduce hemolymph drop spreading, and even provide complete rebound when impacting on inclined surfaces.

  17. Using Mixture Regression to Identify Varying Effects: A Demonstration with Paternal Incarceration

    ERIC Educational Resources Information Center

    Dyer, W. Justin; Pleck, Joseph; McBride, Brent

    2012-01-01

    The most widely used techniques for identifying the varying effects of stressors involve testing moderator effects via interaction terms in regression or multiple-group analysis in structural equation modeling. The authors present mixture regression as an alternative approach. In contrast to more widely used approaches, mixture regression…

  18. Active Control of Liner Impedance by Varying Perforate Orifice Geometry

    NASA Technical Reports Server (NTRS)

    Ahuji, K. K.; Gaeta, R. J., Jr.

    2000-01-01

    The present work explored the feasibility of controlling the acoustic impedance of a resonant type acoustic liner. This was accomplished by translating one perforate over another of the same porosity creating a totally new perforate that had an intermediate porosity. This type of adjustable perforate created a variable orifice perforate whose orifices were non-circular. The key objective of the present study was to quantify, the degree of attenuation control that can be achieved by applying such a concept to the buried septum in a two-degree-of-freedom (2DOF) acoustic liner. An additional objective was to examine the adequacy of the existing impedance models to explain the behavior of the unique orifice shapes that result from the proposed silding perforate concept. Different orifice shapes with equivalent area were also examined to determine if highly non-circular orifices had a significant impact on the impedance.

  19. Time varying networks and the weakness of strong ties

    NASA Astrophysics Data System (ADS)

    Karsai, Márton; Perra, Nicola; Vespignani, Alessandro

    2014-02-01

    In most social and information systems the activity of agents generates rapidly evolving time-varying networks. The temporal variation in networks' connectivity patterns and the ongoing dynamic processes are usually coupled in ways that still challenge our mathematical or computational modelling. Here we analyse a mobile call dataset and find a simple statistical law that characterize the temporal evolution of users' egocentric networks. We encode this observation in a reinforcement process defining a time-varying network model that exhibits the emergence of strong and weak ties. We study the effect of time-varying and heterogeneous interactions on the classic rumour spreading model in both synthetic, and real-world networks. We observe that strong ties severely inhibit information diffusion by confining the spreading process among agents with recurrent communication patterns. This provides the counterintuitive evidence that strong ties may have a negative role in the spreading of information across networks.

  20. Wide-Bandgap Semiconductors

    SciTech Connect

    Chinthavali, M.S.

    2005-11-22

    With the increase in demand for more efficient, higher-power, and higher-temperature operation of power converters, design engineers face the challenge of increasing the efficiency and power density of converters [1, 2]. Development in power semiconductors is vital for achieving the design goals set by the industry. Silicon (Si) power devices have reached their theoretical limits in terms of higher-temperature and higher-power operation by virtue of the physical properties of the material. To overcome these limitations, research has focused on wide-bandgap materials such as silicon carbide (SiC), gallium nitride (GaN), and diamond because of their superior material advantages such as large bandgap, high thermal conductivity, and high critical breakdown field strength. Diamond is the ultimate material for power devices because of its greater than tenfold improvement in electrical properties compared with silicon; however, it is more suited for higher-voltage (grid level) higher-power applications based on the intrinsic properties of the material [3]. GaN and SiC power devices have similar performance improvements over Si power devices. GaN performs only slightly better than SiC. Both SiC and GaN have processing issues that need to be resolved before they can seriously challenge Si power devices; however, SiC is at a more technically advanced stage than GaN. SiC is considered to be the best transition material for future power devices before high-power diamond device technology matures. Since SiC power devices have lower losses than Si devices, SiC-based power converters are more efficient. With the high-temperature operation capability of SiC, thermal management requirements are reduced; therefore, a smaller heat sink would be sufficient. In addition, since SiC power devices can be switched at higher frequencies, smaller passive components are required in power converters. Smaller heat sinks and passive components result in higher-power-density power converters

  1. Detection of Epigenetic Changes Using ANOVA with Spatially Varying Coefficients

    PubMed Central

    Xiao, Guanghua; Wang, Xinlei; LaPlant, Quincey; Nestler, Eric; Xie, Yang

    2016-01-01

    Identification of genome-wide epigenetic changes, the stable changes in gene function without a change in DNA sequence, under various conditions plays an important role in biomedical research. High-throughput epigenetic experiments are useful tools to measure genome-wide epigenetic changes, but the measured intensity levels from these high-resolution genome-wide epigenetic profiling data are often spatially correlated with high noise levels. In addition, no formal statistical method was developed to compare genome-wide epigenetic changes across multiple conditions. In this study, we consider ANOVA models with spatially varying coefficients, combined with a hierarchical Bayes approach, to explicitly model spatial correlation caused by location-dependent biological effects (i.e., epigenetic changes) and borrow strength among neighboring probes to compare epigenetic changes across multiple conditions. Through simulation studies and applications in drug addiction and depression models, we find that our approach compares favorably with competing methods; it is more efficient in estimation and more effective in detecting epigenetic changes. In addition, it can provide biologically meaningful results. PMID:23502341

  2. Detection of epigenetic changes using ANOVA with spatially varying coefficients.

    PubMed

    Guanghua, Xiao; Xinlei, Wang; Quincey, LaPlant; Nestler, Eric J; Xie, Yang

    2013-03-13

    Identification of genome-wide epigenetic changes, the stable changes in gene function without a change in DNA sequence, under various conditions plays an important role in biomedical research. High-throughput epigenetic experiments are useful tools to measure genome-wide epigenetic changes, but the measured intensity levels from these high-resolution genome-wide epigenetic profiling data are often spatially correlated with high noise levels. In addition, it is challenging to detect genome-wide epigenetic changes across multiple conditions, so efficient statistical methodology development is needed for this purpose. In this study, we consider ANOVA models with spatially varying coefficients, combined with a hierarchical Bayesian approach, to explicitly model spatial correlation caused by location-dependent biological effects (i.e., epigenetic changes) and borrow strength among neighboring probes to compare epigenetic changes across multiple conditions. Through simulation studies and applications in drug addiction and depression datasets, we find that our approach compares favorably with competing methods; it is more efficient in estimation and more effective in detecting epigenetic changes. In addition, it can provide biologically meaningful results.

  3. Varying G. [in Einstein gravitation theory

    NASA Technical Reports Server (NTRS)

    Canuto, V.; Hsieh, S.-H.; Owen, J. R.

    1979-01-01

    The problem of the variation of the gravitational constant with cosmological time is critically analyzed. Since Einstein's equation does not allow G to vary on any time scale, no observational data can be analyzed within the context of the standard theory. The recently proposed scale covariant theory, which allows (but does not demand) G to vary, and which has been shown to have passed several standard cosmological tests, is employed to discuss some recent nonnull observational results which indicate a time variation of G.

  4. Relaxation Assessment with Varied Structured Milieu (RELAX).

    ERIC Educational Resources Information Center

    Cassel, Russell N.; Cassel, Susie L.

    1983-01-01

    Describes Relaxation Assessment with Varied Structured Milieu (RELAX), a clinical program designed to assess the degree to which an individual is able to demonstrate self-control for overall general relaxation. The program is designed for use with the Cassel Biosensors biofeedback equipment. (JAC)

  5. Regularizing cosmological singularities by varying physical constants

    SciTech Connect

    Dąbrowski, Mariusz P.; Marosek, Konrad E-mail: k.marosek@wmf.univ.szczecin.pl

    2013-02-01

    Varying physical constant cosmologies were claimed to solve standard cosmological problems such as the horizon, the flatness and the Λ-problem. In this paper, we suggest yet another possible application of these theories: solving the singularity problem. By specifying some examples we show that various cosmological singularities may be regularized provided the physical constants evolve in time in an appropriate way.

  6. The Varied Uses of Readability Measurement.

    ERIC Educational Resources Information Center

    Fry, Edward

    Readability formulas have varied uses. In education they are used to match children's reading ability to the difficulty level of material, select stories and books for classroom use and for individual students' particular needs, select textbooks and other reading materials, aid educational research, and check reading materials of newly literate…

  7. Radon diffusion coefficients in soils of varying moisture content

    NASA Astrophysics Data System (ADS)

    Papachristodoulou, C.; Ioannides, K.; Pavlides, S.

    2009-04-01

    Radon is a naturally occurring radioactive gas that is generated in the Earth's crust and is free to migrate through soil and be released to the atmosphere. Due to its unique properties, soil gas radon has been established as a powerful tracer used for a variety of purposes, such as exploring uranium ores, locating geothermal resources and hydrocarbon deposits, mapping geological faults, predicting seismic activity or volcanic eruptions and testing atmospheric transport models. Much attention has also been given to the radiological health hazard posed by increased radon concentrations in the living and working environment. In order to exploit radon profiles for geophysical purposes and also to predict its entry indoors, it is necessary to study its transport through soils. Among other factors, the importance of soil moisture in such studies has been largely highlighted and it is widely accepted that any measurement of radon transport parameters should be accompanied by a measurement of the soil moisture content. In principle, validation of transport models in the field is encountered by a large number of uncontrollable and varying parameters; laboratory methods are therefore preferred, allowing for experiments to be conducted under well-specified and uniform conditions. In this work, a laboratory technique has been applied for studying the effect of soil moisture content on radon diffusion. A vertical diffusion chamber was employed, in which radon was produced from a 226Ra source, was allowed to diffuse through a soil column and was finally monitored using a silicon surface barrier detector. By solving the steady-state radon diffusion equation, diffusion coefficients (D) were determined for soil samples of varying moisture content (m), from null (m=0) to saturation (m=1). For dry soil, a D value of 4.1×10-7 m2s-1 was determined, which increased moderately by a factor of ~3 for soil with low moisture content, i.e. up to m ~0.2. At higher water fractions, a decrease

  8. Varying potential silicon carbide gas sensor

    NASA Technical Reports Server (NTRS)

    Shields, Virgil B. (Inventor); Ryan, Margaret A. (Inventor); Williams, Roger M. (Inventor)

    1997-01-01

    A hydrocarbon gas detection device operates by dissociating or electro-chemically oxidizing hydrocarbons adsorbed to a silicon carbide detection layer. Dissociation or oxidation are driven by a varying potential applied to the detection layer. Different hydrocarbon species undergo reaction at different applied potentials so that the device is able to discriminate among various hydrocarbon species. The device can operate at temperatures between 100.degree. C. and at least 650.degree. C., allowing hydrocarbon detection in hot exhaust gases. The dissociation reaction is detected either as a change in a capacitor or, preferably, as a change of current flow through an FET which incorporates the silicon carbide detection layers. The silicon carbide detection layer can be augmented with a pad of catalytic material which provides a signal without an applied potential. Comparisons between the catalytically produced signal and the varying potential produced signal may further help identify the hydrocarbon present.

  9. Continuously Varying Critical Exponents Beyond Weak Universality

    PubMed Central

    Khan, N.; Sarkar, P.; Midya, A.; Mandal, P.; Mohanty, P. K.

    2017-01-01

    Renormalization group theory does not restrict the form of continuous variation of critical exponents which occurs in presence of a marginal operator. However, the continuous variation of critical exponents, observed in different contexts, usually follows a weak universality scenario where some of the exponents (e.g., β, γ, ν) vary keeping others (e.g., δ, η) fixed. Here we report ferromagnetic phase transition in (Sm1−yNdy)0.52Sr0.48MnO3 (0.5 ≤ y ≤ 1) single crystals where all three exponents β, γ, δ vary with Nd concentration y. Such a variation clearly violates both universality and weak universality hypothesis. We propose a new scaling theory that explains the present experimental results, reduces to the weak universality as a special case, and provides a generic route leading to continuous variation of critical exponents and multi-criticality. PMID:28327622

  10. The Thermal Collector With Varied Glass Covers

    NASA Astrophysics Data System (ADS)

    Luminosu, I.; Pop, N.

    2010-08-01

    The thermal collector with varied glass covers represents an innovation realized in order to build a collector able to reach the desired temperature by collecting the solar radiation from the smallest surface, with the highest efficiency. In the case of the thermal collector with variable cover glasses, the number of the glass plates covering the absorber increases together with the length of the circulation pipe for the working fluid. The thermal collector with varied glass covers compared to the conventional collector better meet user requirements because: for the same temperature increase, has the collecting area smaller; for the same collection area, realizes the highest temperature increase and has the highest efficiency. This works is addressed to researchers in the solar energy and to engineers responsible with air-conditioning systems design or industrial and agricultural products drying.

  11. Continuously Varying Critical Exponents Beyond Weak Universality

    NASA Astrophysics Data System (ADS)

    Khan, N.; Sarkar, P.; Midya, A.; Mandal, P.; Mohanty, P. K.

    2017-03-01

    Renormalization group theory does not restrict the form of continuous variation of critical exponents which occurs in presence of a marginal operator. However, the continuous variation of critical exponents, observed in different contexts, usually follows a weak universality scenario where some of the exponents (e.g., β, γ, ν) vary keeping others (e.g., δ, η) fixed. Here we report ferromagnetic phase transition in (Sm1‑yNdy)0.52Sr0.48MnO3 (0.5 ≤ y ≤ 1) single crystals where all three exponents β, γ, δ vary with Nd concentration y. Such a variation clearly violates both universality and weak universality hypothesis. We propose a new scaling theory that explains the present experimental results, reduces to the weak universality as a special case, and provides a generic route leading to continuous variation of critical exponents and multi-criticality.

  12. Learning Time-Varying Coverage Functions

    PubMed Central

    Du, Nan; Liang, Yingyu; Balcan, Maria-Florina; Song, Le

    2015-01-01

    Coverage functions are an important class of discrete functions that capture the law of diminishing returns arising naturally from applications in social network analysis, machine learning, and algorithmic game theory. In this paper, we propose a new problem of learning time-varying coverage functions, and develop a novel parametrization of these functions using random features. Based on the connection between time-varying coverage functions and counting processes, we also propose an efficient parameter learning algorithm based on likelihood maximization, and provide a sample complexity analysis. We applied our algorithm to the influence function estimation problem in information diffusion in social networks, and show that with few assumptions about the diffusion processes, our algorithm is able to estimate influence significantly more accurately than existing approaches on both synthetic and real world data. PMID:25960624

  13. Varied line-space gratings and applications

    SciTech Connect

    McKinney, W.R.

    1991-07-15

    This paper presents a straightforward analytical and numerical method for the design of a specific type of varied line-space grating system. The mathematical development will assume plane or nearly-plane spherical gratings which are illuminated by convergent light, which covers many interesting cases for synchrotron radiation. The gratings discussed will have straight grooves whose spacing varies across the principal plane of the grating. Focal relationships and formulae for the optical grating-pole-to-exist-slit distance and grating radius previously presented by other authors will be derived with a symbolic algebra system. It is intended to provide the optical designer with the tools necessary to design such a system properly. Finally, some possible advantages and disadvantages for application to synchrotron to synchrotron radiation beamlines will be discussed.

  14. Synchronization in time-varying networks

    NASA Astrophysics Data System (ADS)

    Kohar, Vivek; Ji, Peng; Choudhary, Anshul; Sinha, Sudeshna; Kurths, Jüergen

    2014-08-01

    We study the stability of the synchronized state in time-varying complex networks using the concept of basin stability, which is a nonlocal and nonlinear measure of stability that can be easily applied to high-dimensional systems [P. J. Menck, J. Heitzig, N. Marwan, and J. Kurths, Nature Phys. 9, 89 (2013), 10.1038/nphys2516]. The time-varying character is included by stochastically rewiring each link with the average frequency f. We find that the time taken to reach synchronization is lowered and the stability range of the synchronized state increases considerably in dynamic networks. Further we uncover that small-world networks are much more sensitive to link changes than random ones, with the time-varying character of the network having a significant effect at much lower rewiring frequencies. At very high rewiring frequencies, random networks perform better than small-world networks and the synchronized state is stable over a much wider window of coupling strengths. Lastly we show that the stability range of the synchronized state may be quite different for small and large perturbations, and so the linear stability analysis and the basin stability criterion provide complementary indicators of stability.

  15. Synchronization in time-varying networks.

    PubMed

    Kohar, Vivek; Ji, Peng; Choudhary, Anshul; Sinha, Sudeshna; Kurths, Jüergen

    2014-08-01

    We study the stability of the synchronized state in time-varying complex networks using the concept of basin stability, which is a nonlocal and nonlinear measure of stability that can be easily applied to high-dimensional systems [P. J. Menck, J. Heitzig, N. Marwan, and J. Kurths, Nature Phys. 9, 89 (2013)]. The time-varying character is included by stochastically rewiring each link with the average frequency f. We find that the time taken to reach synchronization is lowered and the stability range of the synchronized state increases considerably in dynamic networks. Further we uncover that small-world networks are much more sensitive to link changes than random ones, with the time-varying character of the network having a significant effect at much lower rewiring frequencies. At very high rewiring frequencies, random networks perform better than small-world networks and the synchronized state is stable over a much wider window of coupling strengths. Lastly we show that the stability range of the synchronized state may be quite different for small and large perturbations, and so the linear stability analysis and the basin stability criterion provide complementary indicators of stability.

  16. Does thermal time for germination vary among populations of a tree legume (Peltophorum dubium)?

    PubMed

    Andrade, L F D; Cardoso, V J M

    2016-04-19

    Few works report the use of degree-days (DD) - used in crops to predict events and schedule management activities - to describe the germination of tropical trees. The cardinal temperatures (base, optimum and ceiling temperature) for germination of the species may vary depending on the seed provenance. Peltophorum dubium (Spreng.) Taub. is an early successional leguminous tree widely distributed in South America, often occurring as cultivated or naturalized trees, thus considered to be a good example for testing DD model in tree species. The main objective of this study was to describe the seed germination response of different populations of P. dubium as function of DD accumulation during germination assays in semi-controlled (fluctuating temperatures) conditions. Germination assays with manually scarified seeds sown in aluminum sheet trays filled with a composed substrate were performed under greenhouse conditions at different times. Three methods were employed in order to describe the accumulation of thermal time throughout the assays and, considering the seed lot and sowing time, a trapezoid area method was relatively more effective in describing the germination. The germination curves of P. dubium seeds from different populations, expressed in degree-days estimated directly from temperature records schedules, tend to be more clustered suggesting little variation among thermal time requirements in different seed provenances. Otherwise, the thermal time requirement can vary depending on the time of sowing, and any increase in DD requirement when the assays were performed under higher mean temperatures can be related to a thermal effect on the germination of scarified seeds.

  17. The World Wide Web: Alice Meets Cyberspace.

    ERIC Educational Resources Information Center

    Koos, Marybeth; Smith-Shank, Deborah L.

    1996-01-01

    Uses excerpts from "Alice In Wonderland" as introductions to a tour of the uses of the World Wide Web in art education. Discusses such issues as access, copyrights, costs, and benefits. Includes an index of terms, list of related Websites, and suggested teaching activities. (MJP)

  18. Rivers at Risk: An Activity Based Study Guide for the Colorado River Basin.

    ERIC Educational Resources Information Center

    Samples, Bob, Ed.

    This activity guide is intended to increase student awareness and understanding about the Colorado River Basin. Each activity includes objectives, procedures, materials list, related activities, questions for students, and related information. The activities are varied to appeal to a wide range of learning styles and modalities and are…

  19. Cannabinoid CB2 receptor activation inhibits mechanically evoked responses of wide dynamic range dorsal horn neurons in naïve rats and in rat models of inflammatory and neuropathic pain.

    PubMed

    Elmes, Steven J R; Jhaveri, Maulik D; Smart, Darren; Kendall, David A; Chapman, Victoria

    2004-11-01

    Peripheral cannabinoid 2 receptors (CB2 receptors) modulate immune responses and attenuate nociceptive behaviour in models of acute and persistent pain. The aim of the present study was to investigate whether peripheral CB2 receptors modulate spinal processing of innocuous and noxious responses and to determine whether there are altered roles of CB2 receptors in models of persistent pain. Effects of local administration of the CB2 receptor agonist JWH-133 (5 and 15 microg/50 microL) on mechanically evoked responses of spinal wide dynamic range (WDR) neurons in noninflamed rats, rats with carrageenan-induced hindpaw inflammation, sham operated rats and spinal nerve-ligated (SNL) rats were determined in anaesthetized rats in vivo. Mechanical stimulation (von Frey filaments, 6-80 g) of the peripheral receptive field evoked firing of WDR neurons. Mechanically evoked responses of WDR neurons were similar in noninflamed, carrageenan-inflamed, sham-operated and SNL rats. Intraplantar injection of JWH-133 (15 microg), but not vehicle, significantly (P < 0.05) inhibited innocuous and noxious mechanically evoked responses of WDR neurons in all four groups of rats. In many cases the selective CB2 receptor antagonist, SR144528 (10 microg/50 microL), attenuated the inhibitory effects of JWH-133 (15 microg) on mechanically evoked WDR neuronal responses. The CB1 receptor antagonist, SR141716A, did not attenuate the inhibitory effects of JWH-133 on these responses. Intraplantar preadministration of JWH-133 also inhibited (P < 0.05) carrageenan-induced expansion of peripheral receptive fields of WDR dorsal horn neurons. This study demonstrates that activation of peripheral CB2 receptors attenuates both innocuous- and noxious-evoked responses of WDR neurons in models of acute, inflammatory and neuropathic pain.

  20. A varying polytropic gas universe and phase space analysis

    NASA Astrophysics Data System (ADS)

    Khurshudyan, M.

    2016-05-01

    In this paper, we will consider a phenomenological model of a dark fluid that is able to explain an accelerated expansion of our low redshift universe and the phase transition to this accelerated expanding universe. Recent developments in modern cosmology towards understanding of the accelerated expansion of the large scale universe involve various scenarios and approaches. Among these approaches, one of well-known and accepted practice is modeling of the content of our universe via dark fluid. There are various models of dark energy fluid actively studied in recent literature and polytropic gas is among them. In this work, we will consider a varying polytropic gas which is a phenomenological modification of polytropic gas. Our model of varying polytropic dark fluid has been constructed to analogue to a varying Chaplygin gas actively discussed in the literature. We will consider interacting models, where dark matter is a pressureless fluid, to have a comprehensive picture. Phase space analysis is an elegant mathematical tool to earn general understanding of large scale universe and easily see an existence of a solution to cosmological coincidence problem. Imposing some constraints on parameters of the models, we found late time attractors for each case analytically. Cosmological consequences for the obtained late time attractors are discussed.

  1. Linear Parameter Varying Control for Actuator Failure

    NASA Technical Reports Server (NTRS)

    Shin, Jong-Yeob; Wu, N. Eva; Belcastro, Christine; Bushnell, Dennis M. (Technical Monitor)

    2002-01-01

    A robust linear parameter varying (LPV) control synthesis is carried out for an HiMAT vehicle subject to loss of control effectiveness. The scheduling parameter is selected to be a function of the estimates of the control effectiveness factors. The estimates are provided on-line by a two-stage Kalman estimator. The inherent conservatism of the LPV design is reducing through the use of a scaling factor on the uncertainty block that represents the estimation errors of the effectiveness factors. Simulations of the controlled system with the on-line estimator show that a superior fault-tolerance can be achieved.

  2. 3D-printing spatially varying BRDFs.

    PubMed

    Rouiller, Olivier; Bickel, Bernd; Kautz, Jan; Matusik, Wojciech; Alexa, Marc

    2013-01-01

    A new method fabricates custom surface reflectance and spatially varying bidirectional reflectance distribution functions (svBRDFs). Researchers optimize a microgeometry for a range of normal distribution functions and simulate the resulting surface's effective reflectance. Using the simulation's results, they reproduce an input svBRDF's appearance by distributing the microgeometry on the printed material's surface. This method lets people print svBRDFs on planar samples with current 3D printing technology, even with a limited set of printing materials. It extends naturally to printing svBRDFs on arbitrary shapes.

  3. A time-varying magnetic flux concentrator

    NASA Astrophysics Data System (ADS)

    Kibret, B.; Premaratne, M.; Lewis, P. M.; Thomson, R.; Fitzgerald, P. B.

    2016-08-01

    It is known that diverse technological applications require the use of focused magnetic fields. This has driven the quest for controlling the magnetic field. Recently, the principles in transformation optics and metamaterials have allowed the realization of practical static magnetic flux concentrators. Extending such progress, here, we propose a time-varying magnetic flux concentrator cylindrical shell that uses electric conductors and ferromagnetic materials to guide magnetic flux to its center. Its performance is discussed based on finite-element simulation results. Our proposed design has potential applications in magnetic sensors, medical devices, wireless power transfer, and near-field wireless communications.

  4. Genome-wide discovery of loci influencing chemotherapy cytotoxicity.

    PubMed

    Watters, James W; Kraja, Aldi; Meucci, Melissa A; Province, Michael A; McLeod, Howard L

    2004-08-10

    Little is known about the heritability of chemotherapy activity or the identity of genes that may enable the individualization of cancer chemotherapy. Although numerous genes are likely to influence chemotherapy response, current candidate gene-based pharmacogenetics approaches require a priori knowledge and the selection of a small number of candidate genes for hypothesis testing. In this study, an ex vivo familial genetics strategy using lymphoblastoid cells derived from Centre d'Etude du Polymorphisme Humain reference pedigrees was used to discover genetic determinants of chemotherapy cytotoxicity. Cytotoxicity to the mechanistically distinct chemotherapy agents 5-fluorouracil and docetaxel were shown to be heritable traits, with heritability values ranging from 0.26 to 0.65 for 5-fluorouracil and 0.21 to 0.70 for docetaxel, varying with dose. Genome-wide linkage analysis was also used to map a quantitative trait locus influencing the cellular effects of 5-fluorouracil to chromosome 9q13-q22 [logarithm of odds (LOD) = 3.44], and two quantitative trait loci influencing the cellular effects of docetaxel to chromosomes 5q11-21 (LOD = 2.21) and 9q13-q22 (LOD = 2.73). Finally, 5-fluorouracil and docetaxel were shown to cause apoptotic cell death involving caspase-3 cleavage in Centre d'Etude du Polymorphisme Humain lymphoblastoid cells. This study identifies genomic regions likely to harbor genes important for chemotherapy cytotoxicity using genome-wide linkage analysis in human pedigrees and provides a widely applicable strategy for pharmacogenomic discovery without the requirement for a priori candidate gene selection.

  5. Energy-based stochastic control of neural mass models suggests time-varying effective connectivity in the resting state.

    PubMed

    Sotero, Roberto C; Shmuel, Amir

    2012-06-01

    Several studies posit energy as a constraint on the coding and processing of information in the brain due to the high cost of resting and evoked cortical activity. This suggestion has been addressed theoretically with models of a single neuron and two coupled neurons. Neural mass models (NMMs) address mean-field based modeling of the activity and interactions between populations of neurons rather than a few neurons. NMMs have been widely employed for studying the generation of EEG rhythms, and more recently as frameworks for integrated models of neurophysiology and functional MRI (fMRI) responses. To date, the consequences of energy constraints on the activity and interactions of ensembles of neurons have not been addressed. Here we aim to study the impact of constraining energy consumption during the resting-state on NMM parameters. To this end, we first linearized the model, then used stochastic control theory by introducing a quadratic cost function, which transforms the NMM into a stochastic linear quadratic regulator (LQR). Solving the LQR problem introduces a regime in which the NMM parameters, specifically the effective connectivities between neuronal populations, must vary with time. This is in contrast to current NMMs, which assume a constant parameter set for a given condition or task. We further simulated energy-constrained stochastic control of a specific NMM, the Wilson and Cowan model of two coupled neuronal populations, one of which is excitatory and the other inhibitory. These simulations demonstrate that with varying weights of the energy-cost function, the NMM parameters show different time-varying behavior. We conclude that constraining NMMs according to energy consumption may create more realistic models. We further propose to employ linear NMMs with time-varying parameters as an alternative to traditional nonlinear NMMs with constant parameters.

  6. Cell response to silica gels with varying mechanical properties

    NASA Astrophysics Data System (ADS)

    Lefebvre, Molly Ann

    Sol-gel encapsulation has a variety of applications in biotechnology and medicine: creating biosensors, biocatalysts, and bioartificial organs. However, encapsulated cell viability is a major challenge. Consequently, interactions between cells and their 3D microenvironment were studied through rheological, metabolic activity, and extraction studies to aid in the development of new gel protocols. The cells were encapsulated in variations of three silica sol-gels with varying stiffness. It was hypothesized that the cell viability and the amount of extracted cells would depend on gel stiffness. For two gels, there was no apparent correlation between the gel stiffness and the cell viability and extracted cell quantity. These gels did strongly depend on the varying gel ingredient, polyethylene glycol. The third gel appeared to follow the hypothesized correlation, but it was not statistically significant. Finally, one gel had a significantly longer period of cell viability and higher quantity of extracted cells than the other gels.

  7. Transient, spatially varied groundwater recharge modeling

    NASA Astrophysics Data System (ADS)

    Assefa, Kibreab Amare; Woodbury, Allan D.

    2013-08-01

    The objective of this work is to integrate field data and modeling tools in producing temporally and spatially varying groundwater recharge in a pilot watershed in North Okanagan, Canada. The recharge modeling is undertaken by using the Richards equation based finite element code (HYDRUS-1D), ArcGIS™, ROSETTA, in situ observations of soil temperature and soil moisture, and a long-term gridded climate data. The public version of HYDUS-1D and another version with detailed freezing and thawing module are first used to simulate soil temperature, snow pack, and soil moisture over a one year experimental period. Statistical analysis of the results show both versions of HYDRUS-1D reproduce observed variables to the same degree. After evaluating model performance using field data and ROSETTA derived soil hydraulic parameters, the HYDRUS-1D code is coupled with ArcGIS™ to produce spatially and temporally varying recharge maps throughout the Deep Creek watershed. Temporal and spatial analysis of 25 years daily recharge results at various representative points across the study watershed reveal significant temporal and spatial variations; average recharge estimated at 77.8 ± 50.8 mm/year. Previous studies in the Okanagan Basin used Hydrologic Evaluation of Landfill Performance without any attempt of model performance evaluation, notwithstanding its inherent limitations. Thus, climate change impact results from this previous study and similar others, such as Jyrkama and Sykes (2007), need to be interpreted with caution.

  8. Brown Dwarf Variability: What's Varying and Why?

    NASA Technical Reports Server (NTRS)

    Marley, Mark Scott

    2014-01-01

    Surveys by ground based telescopes, HST, and Spitzer have revealed that brown dwarfs of most spectral classes exhibit variability. The spectral and temporal signatures of the variability are complex and apparently defy simplistic classification which complicates efforts to model the changes. Important questions include understanding if clearings are forming in an otherwise uniform cloud deck or if thermal perturbations, perhaps associated with breaking gravity waves, are responsible. If clouds are responsible how long does it take for the atmospheric thermal profile to relax from a hot cloudy to a cooler cloudless state? If thermal perturbations are responsible then what atmospheric layers are varying? How do the observed variability timescales compare to atmospheric radiative, chemical, and dynamical timescales? I will address such questions by presenting modeling results for time-varying partly cloudy atmospheres and explore the importance of various atmospheric processes over the relevant timescales for brown dwarfs of a range of effective temperatures. Regardless of the origin of the observed variability, the complexity seen in the atmospheres of the field dwarfs hints at the variability that we may encounter in the next few years in directly imaged young Jupiters. Thus understanding the nature of variability in the field dwarfs, including sensitivity to gravity and metallicity, is of particular importance for exoplanet characterization.

  9. Premorbid IQ varies across different definitions of schizophrenia

    PubMed Central

    URFER PARNAS, ANNICK; JANSSON, LENNART; HANDEST, PETER; NIELSEN, JAN; SÆBYE, DITTE; PARNAS, JOSEF

    2007-01-01

    The nature of the association between IQ and schizophrenia is still unclear. So far no study addressed this issue in relation to the breadth or scope of the very concept of schizophrenia. We examined the premorbid IQ in a polydiagnostic study with four classifications of schizophrenia: ICD-8/9, ICD-10, St. Louis and Flexible System-Wide. Only the ICD-10 schizophrenia patients exhibited a significantly lower premorbid IQ. There were suggestive differences between the four examined systems as well as between the ICD-10 paranoid and non-paranoid subtypes. Exploration of crucial diagnostic features of schizophrenia in relation to IQ revealed associations between low premorbid IQ and hallucinations as well as negative symptoms. It is concluded that premorbid IQ varies across different definitions of schizophrenia. PMID:17342225

  10. Diversity-stability relationship varies with latitude in zooplankton.

    PubMed

    Shurin, Jonathan B; Arnott, Shelley E; Hillebrand, Helmut; Longmuir, Allyson; Pinel-Alloul, Bernadette; Winder, Monika; Yan, Norman D

    2007-02-01

    Analyses of temporal patterns of diversity across a wide range of taxa have found that more diverse communities often show smaller compositional changes over time. This generality indicates that high diversity is associated with greater temporal stability in species composition. We examined patterns of diversity and community stability in zooplankton time series data from 36 lakes sampled over a combined 483 years. The species-time relationship was flatter in more species-rich lakes in the temperate zone. However, high-latitude lakes had both low richness and low turnover. These patterns were consistent for turnover both within and among years. Daily, annual and long-term richness were all higher in large lakes while turnover was unaffected by the surface area. Richness on all time scales, as well as turnover within and among years, all declined at high latitude. Species-area relations and latitudinal gradients in richness therefore reflect different temporal components of diversity. Our results suggest that diversity shows strong associations with compositional stability that vary qualitatively across biogeographical provinces. Community stability increases with diversity among lakes in the temperate zone; however, the two are negatively correlated across latitudinal gradients. These patterns indicate that either the direct effects of diversity on stability or their covariance with environmental fluctuations vary with latitude.

  11. An ETAS model with varying productivity rates

    NASA Astrophysics Data System (ADS)

    Harte, D. S.

    2014-07-01

    We present an epidemic type aftershock sequenc (ETAS) model where the offspring rates vary both spatially and temporally. This is achieved by distinguishing between those space-time volumes where the interpoint space and time distances are small, and those where they are considerably larger. We also question the nature of the background component in the ETAS model. Is it simply a temporal boundary correction (t = 0) or does it represent an additional tectonic process not described by the aftershock component? The form of these stochastic models should not be considered to be fixed. As we accumulate larger and better earthquake catalogues, GPS data, strain rates, etc., we have the ability to ask more complex questions about the nature of the process. By fitting modified models consistent with such questions, we should gain a better insight into the earthquake process. Hence, we consider a sequence of incrementally modified ETAS type models rather than `the' ETAS model.

  12. Tuning ferromagnetism by varying ion beam profiles

    NASA Astrophysics Data System (ADS)

    Hariwal, Rajesh V.; Malik, Hitendra K.; Asokan, K.

    2017-02-01

    Present study demonstrates a novel technique to tune the ferromagnetism at room temperature by varying the ion beam profiles from 3 to 7 mm during Carbon ion implantation in ZnO matrix and keeping other beam parameters constant. The interaction of implanted C ions with host ZnO matrix at different profiles result in variable ferromagnetism from 0.75 to 3.0  ×  10‑4 emu gm‑1 due to difference in the induced radiation pressure. Similar variation is also observed in the optical bandgap from 3.35 to 3.24 eV for different beam profiles. This study shows that the material properties can be tuned and controlled by the variation of beam profiles during the ion implantation.

  13. Time varying arctic climate change amplification

    SciTech Connect

    Chylek, Petr; Dubey, Manvendra K; Lesins, Glen; Wang, Muyin

    2009-01-01

    During the past 130 years the global mean surface air temperature has risen by about 0.75 K. Due to feedbacks -- including the snow/ice albedo feedback -- the warming in the Arctic is expected to proceed at a faster rate than the global average. Climate model simulations suggest that this Arctic amplification produces warming that is two to three times larger than the global mean. Understanding the Arctic amplification is essential for projections of future Arctic climate including sea ice extent and melting of the Greenland ice sheet. We use the temperature records from the Arctic stations to show that (a) the Arctic amplification is larger at latitudes above 700 N compared to those within 64-70oN belt, and that, surprisingly; (b) the ratio of the Arctic to global rate of temperature change is not constant but varies on the decadal timescale. This time dependence will affect future projections of climate changes in the Arctic.

  14. Varying ghost dark energy and particle creation

    NASA Astrophysics Data System (ADS)

    Khurshudyan, M.

    2016-02-01

    One of the models of dark energy is the ghost dark energy, which has a geometrical origin. Recently, a certain type of phenomenological modification of ghost dark energy has been suggested which motivated us for this work. The goal of this paper is twofold. First, we would like to study the cosmological scenario involving interacting varying ghost dark energy. A cosmographic analysis of a non-interacting model is also performed. Then, we study the particle creation following the straight analogy between quantization in Minkowski background and canonical quantization of a scalar field in curved dynamical backgrounds. Particular attention will be paid to massless-particle production from a radiation-dominated universe (according to our toy model) which evolves to our large-scale universe. Constraints on the parameters of the models obtained during the cosmographic analysis did allow to demonstrate the possibility of a massless-particle creation in a radiation-dominated universe.

  15. Photon Propagation in Slowly Varying Electromagnetic Fields

    NASA Astrophysics Data System (ADS)

    Karbstein, F.

    2017-03-01

    Effective theory of soft photons in slowly varying electromagnetic background fields is studied at one-loop order in QED. This is of relevance for the study of all-optical signatures of quantum vacuum nonlinearity in realistic electromagnetic background fields as provided by high-intensity lasers. The central result derived in this article is a new analytical expression for the photon polarization tensor in two linearly polarized counterpropagating pulsed Gaussian laser beams. Treating the peak field strengths of both laser beams as free parameters, this field configuration can be considered as interpolating between the limiting cases of a purely right- or left-moving laser beam (if one of the peak field strengths is set equal to zero) and the standing-wave type scenario with two counter-propagating beams of equal strength.

  16. [Comparative toxicity of photosensitizers in varying destruction].

    PubMed

    Sinitsina, O O; Zholdakova, Z I; Poliakova, E E; Golovach, E N; Sycheva, L P; Beliaeva, N N; Kuznetsova, N A

    2007-01-01

    The toxicity of the photosensitizers proflavine acetate (PA) versus methylene blue (MB) was evaluated during their varying destruction. Under the influence of visible light, a partial (25%) transformation of the photosensitizers was shown to be attended by their enhanced toxicity and 100% destruction of the parent substances caused a reduction in their hazard. PA and its phototransformation products mainly affect the antiperoxide protection system and the structural and functional states of the liver, kidney, and duodenum. The maximum noneffective dose is 0.002 mg/kg. The possibility of using PA for water disinfection depends on the ratio of safe and effective concentrations. A partial (25%) MB destruction products cause mutagenic effects; the permissible dose of the mutagen is 0.00025 mg/kg. MB is not recommended for disinfection of all types of waters.

  17. Application of Hamilton's law of varying action

    NASA Technical Reports Server (NTRS)

    Bailey, C. D.

    1975-01-01

    The law of varying action enunciated by Hamilton in 1834-1835 permits the direct analytical solution of the problems of mechanics, both stationary and nonstationary, without consideration of force equilibrium and the theory of differential equations associated therewith. It has not been possible to obtain direct analytical solutions to nonstationary systems through the use of energy theory, which has been limited for 140 years to the principle of least action and to Hamilton's principle. It is shown here that Hamilton's law permits the direct analytical solution to nonstationary, initial value systems in the mechanics of solids without any knowledge or use of the theory of differential equations. Solutions are demonstrated for nonconservative, nonstationary particle motion, both linear and nonlinear.

  18. Time varying, multivariate volume data reduction

    SciTech Connect

    Ahrens, James P; Fout, Nathaniel; Ma, Kwan - Liu

    2010-01-01

    Large-scale supercomputing is revolutionizing the way science is conducted. A growing challenge, however, is understanding the massive quantities of data produced by large-scale simulations. The data, typically time-varying, multivariate, and volumetric, can occupy from hundreds of gigabytes to several terabytes of storage space. Transferring and processing volume data of such sizes is prohibitively expensive and resource intensive. Although it may not be possible to entirely alleviate these problems, data compression should be considered as part of a viable solution, especially when the primary means of data analysis is volume rendering. In this paper we present our study of multivariate compression, which exploits correlations among related variables, for volume rendering. Two configurations for multidimensional compression based on vector quantization are examined. We emphasize quality reconstruction and interactive rendering, which leads us to a solution using graphics hardware to perform on-the-fly decompression during rendering. In this paper we present a solution which addresses the need for data reduction in large supercomputing environments where data resulting from simulations occupies tremendous amounts of storage. Our solution employs a lossy encoding scheme to acrueve data reduction with several options in terms of rate-distortion behavior. We focus on encoding of multiple variables together, with optional compression in space and time. The compressed volumes can be rendered directly with commodity graphics cards at interactive frame rates and rendering quality similar to that of static volume renderers. Compression results using a multivariate time-varying data set indicate that encoding multiple variables results in acceptable performance in the case of spatial and temporal encoding as compared to independent compression of variables. The relative performance of spatial vs. temporal compression is data dependent, although temporal compression has the

  19. Optimal transport in time-varying small-world networks

    NASA Astrophysics Data System (ADS)

    Chen, Qu; Qian, Jiang-Hai; Zhu, Liang; Han, Ding-Ding

    2016-03-01

    The time-order of interactions, which is regulated by some intrinsic activity, surely plays a crucial role regarding the transport efficiency of transportation systems. Here we study the optimal transport structure by measure of the length of time-respecting paths. Our network is built from a two-dimensional regular lattice, and long-range connections are allocated with probability Pi j˜rij -α , where ri j is the Manhattan distance. By assigning each shortcut an activity rate subjected to its geometric distance τi j˜rij -C , long-range links become active intermittently, leading to the time-varying dynamics. We show that for 0 varying transportation networks. Empirical studies on British Airways and Austrian Airlines provide consistent evidence with our conclusion.

  20. The impacts of forest management strategies for woodland caribou vary across biogeographic gradients

    PubMed Central

    Brown, Glen S.; Mallory, Frank F.

    2017-01-01

    Loss or alteration of forest ecosystems due to anthropogenic activities has prompted the need for mitigation measures aimed at protecting habitat for forest-dependent wildlife. Understanding how wildlife respond to such management efforts is essential for achieving conservation targets. Boreal caribou are a species of conservation concern due to the impacts of human induced habitat alteration; however the effects of habitat management activities are poorly understood. We assessed the relationship between large scale patterns in forest harvesting and caribou spatial behaviours over a 20-year period, spanning a change in forest management intended to protect caribou habitat. Caribou range size, fidelity, and proximity to forest harvests were assessed in relation to change in harvest patterns through time and across two landscapes that varied widely in natural disturbance and community dynamics. We observed up to 89% declines in total area harvested within our study areas, with declining harvest size and aggregation. These landscape outcomes were coincident with caribou exhibiting greater fidelity and spacing farther away from disturbances at smaller scales, hypothesized to be beneficial for acquiring food and avoiding predators. Contrary to our expectation that the large scale maintenance of habitat patches would permit caribou to space away from disturbance, their proximity to harvest blocks at the population range scale did not decrease through time, suggesting that movement toward landscape recovery for caribou in previously harvested regions will likely stretch over multiple decades. Caribou spatial behaviours varied across the two landscapes independently of forest management. Our study underlines the importance of understanding both changes in industry demands, as well as natural landscape variation in habitat when managing wildlife. PMID:28234901

  1. System Wide Information Management (SWIM)

    NASA Technical Reports Server (NTRS)

    Hritz, Mike; McGowan, Shirley; Ramos, Cal

    2004-01-01

    This viewgraph presentation lists questions regarding the implementation of System Wide Information Management (SWIM). Some of the questions concern policy issues and strategies, technology issues and strategies, or transition issues and strategies.

  2. Lamb Wave Propagation in Varying Thermal Environments

    DTIC Science & Technology

    2007-03-01

    recent years. Typical Nondestructive Evaluation ( NDE ) techniques include ultrasonic technology, acoustic emission, magnetic field analysis, penetrant...sensor. Therefore, they have been combined with other NDE techniques to identify the location of damage in larger structures. The pitch-catch method...Piezoelectric Wafer Active Sensor Ultrasonics One new method implemented in the NDE of structures is the use of the Piezoelectric Wafer Active Sensor

  3. A Self-Teaching Scheme in Applied Science (Physics and Chemistry) for Students of Widely Varying Background Knowledge.

    ERIC Educational Resources Information Center

    Horsey, Joan; Milson, A.

    1980-01-01

    Summarizes the findings of an investigation of a self-teaching scheme of selected topics in physics and chemistry used with students taking courses in catering, hotel/catering, and institutional management and diploma in home economics. Two complementary experimental approaches are used: statistical analysis of the data and semistructured…

  4. Rumen microbial community composition varies with diet and host, but a core microbiome is found across a wide geographical range.

    PubMed

    Henderson, Gemma; Cox, Faith; Ganesh, Siva; Jonker, Arjan; Young, Wayne; Janssen, Peter H

    2015-10-09

    Ruminant livestock are important sources of human food and global greenhouse gas emissions. Feed degradation and methane formation by ruminants rely on metabolic interactions between rumen microbes and affect ruminant productivity. Rumen and camelid foregut microbial community composition was determined in 742 samples from 32 animal species and 35 countries, to estimate if this was influenced by diet, host species, or geography. Similar bacteria and archaea dominated in nearly all samples, while protozoal communities were more variable. The dominant bacteria are poorly characterised, but the methanogenic archaea are better known and highly conserved across the world. This universality and limited diversity could make it possible to mitigate methane emissions by developing strategies that target the few dominant methanogens. Differences in microbial community compositions were predominantly attributable to diet, with the host being less influential. There were few strong co-occurrence patterns between microbes, suggesting that major metabolic interactions are non-selective rather than specific.

  5. Rumen microbial community composition varies with diet and host, but a core microbiome is found across a wide geographical range

    PubMed Central

    Henderson, Gemma; Cox, Faith; Ganesh, Siva; Jonker, Arjan; Young, Wayne; Abecia, Leticia; Angarita, Erika; Aravena, Paula; Nora Arenas, Graciela; Ariza, Claudia; Attwood, Graeme T.; Mauricio Avila, Jose; Avila-Stagno, Jorge; Bannink, André; Barahona, Rolando; Batistotti, Mariano; Bertelsen, Mads F.; Brown-Kav, Aya; Carvajal, Andres M.; Cersosimo, Laura; Vieira Chaves, Alexandre; Church, John; Clipson, Nicholas; Cobos-Peralta, Mario A.; Cookson, Adrian L.; Cravero, Silvio; Cristobal Carballo, Omar; Crosley, Katie; Cruz, Gustavo; Cerón Cucchi, María; de la Barra, Rodrigo; De Menezes, Alexandre B.; Detmann, Edenio; Dieho, Kasper; Dijkstra, Jan; dos Reis, William L. S.; Dugan, Mike E. R.; Hadi Ebrahimi, Seyed; Eythórsdóttir, Emma; Nde Fon, Fabian; Fraga, Martín; Franco, Francisco; Friedeman, Chris; Fukuma, Naoki; Gagić, Dragana; Gangnat, Isabelle; Javier Grilli, Diego; Guan, Le Luo; Heidarian Miri, Vahideh; Hernandez-Sanabria, Emma; Gomez, Alma Ximena Ibarra; Isah, Olubukola A.; Ishaq, Suzanne; Jami, Elie; Jelincic, Juan; Kantanen, Juha; Kelly, William J.; Kim, Seon-Ho; Klieve, Athol; Kobayashi, Yasuo; Koike, Satoshi; Kopecny, Jan; Nygaard Kristensen, Torsten; Julie Krizsan, Sophie; LaChance, Hannah; Lachman, Medora; Lamberson, William R.; Lambie, Suzanne; Lassen, Jan; Leahy, Sinead C.; Lee, Sang-Suk; Leiber, Florian; Lewis, Eva; Lin, Bo; Lira, Raúl; Lund, Peter; Macipe, Edgar; Mamuad, Lovelia L.; Cuquetto Mantovani, Hilário; Marcoppido, Gisela Ariana; Márquez, Cristian; Martin, Cécile; Martinez, Gonzalo; Eugenia Martinez, Maria; Lucía Mayorga, Olga; McAllister, Tim A.; McSweeney, Chris; Mestre, Lorena; Minnee, Elena; Mitsumori, Makoto; Mizrahi, Itzhak; Molina, Isabel; Muenger, Andreas; Munoz, Camila; Murovec, Bostjan; Newbold, John; Nsereko, Victor; O’Donovan, Michael; Okunade, Sunday; O’Neill, Brendan; Ospina, Sonia; Ouwerkerk, Diane; Parra, Diana; Pereira, Luiz Gustavo Ribeiro; Pinares-Patino, Cesar; Pope, Phil B.; Poulsen, Morten; Rodehutscord, Markus; Rodriguez, Tatiana; Saito, Kunihiko; Sales, Francisco; Sauer, Catherine; Shingfield, Kevin; Shoji, Noriaki; Simunek, Jiri; Stojanović-Radić, Zorica; Stres, Blaz; Sun, Xuezhao; Swartz, Jeffery; Liang Tan, Zhi; Tapio, Ilma; Taxis, Tasia M.; Tomkins, Nigel; Ungerfeld, Emilio; Valizadeh, Reza; van Adrichem, Peter; Van Hamme, Jonathan; Van Hoven, Woulter; Waghorn, Garry; John Wallace, R.; Wang, Min; Waters, Sinéad M.; Keogh, Kate; Witzig, Maren; Wright, Andre-Denis G.; Yamano, Hidehisa; Yan, Tianhai; Yanez-Ruiz, David R.; Yeoman, Carl J.; Zambrano, Ricardo; Zeitz, Johanna; Zhou, Mi; Wei Zhou, Hua; Xia Zou, Cai; Zunino, Pablo; Janssen, Peter H.

    2015-01-01

    Ruminant livestock are important sources of human food and global greenhouse gas emissions. Feed degradation and methane formation by ruminants rely on metabolic interactions between rumen microbes and affect ruminant productivity. Rumen and camelid foregut microbial community composition was determined in 742 samples from 32 animal species and 35 countries, to estimate if this was influenced by diet, host species, or geography. Similar bacteria and archaea dominated in nearly all samples, while protozoal communities were more variable. The dominant bacteria are poorly characterised, but the methanogenic archaea are better known and highly conserved across the world. This universality and limited diversity could make it possible to mitigate methane emissions by developing strategies that target the few dominant methanogens. Differences in microbial community compositions were predominantly attributable to diet, with the host being less influential. There were few strong co-occurrence patterns between microbes, suggesting that major metabolic interactions are non-selective rather than specific. PMID:26449758

  6. Making Use of a Decade of Widely Varying Historical Data: SARP Project - "Full Life-Cycle Defect Management"

    NASA Technical Reports Server (NTRS)

    Shull, Forrest; Godfrey, Sally; Bechtel, Andre; Feldmann, Raimund L.; Regardie, Myrna; Seaman, Carolyn

    2008-01-01

    A viewgraph presentation describing the NASA Software Assurance Research Program (SARP) project, with a focus on full life-cycle defect management, is provided. The topics include: defect classification, data set and algorithm mapping, inspection guidelines, and tool support.

  7. Making Use of a Decade of Widely Varying Historical Data: SARP Project "Full Life-cycle Defect Management"

    NASA Technical Reports Server (NTRS)

    Shull, Forrest; Bechtel, Andre; Feldmann, Raimund L.; Regardie, Myrna; Seaman, Carolyn

    2008-01-01

    This viewgraph presentation addresses the question of inspection and verification and validation (V&V) effectiveness of developing computer systems. A specific question is the relation between V&V effectiveness in the early lifecycle of development and the later testing of the developed system.

  8. Genome-Wide Analysis of Yield in Europe: Allelic Effects Vary with Drought and Heat Scenarios1[OPEN

    PubMed Central

    Millet, Emilie J.; Welcker, Claude; Kruijer, Willem; Negro, Sandra; Coupel-Ledru, Aude; Laborde, Jacques; Bauland, Cyril; Praud, Sebastien; Presterl, Thomas; Usadel, Björn; Charcosset, Alain; Van Eeuwijk, Fred; Tardieu, François

    2016-01-01

    Assessing the genetic variability of plant performance under heat and drought scenarios can contribute to reduce the negative effects of climate change. We propose here an approach that consisted of (1) clustering time courses of environmental variables simulated by a crop model in current (35 years × 55 sites) and future conditions into six scenarios of temperature and water deficit as experienced by maize (Zea mays L.) plants; (2) performing 29 field experiments in contrasting conditions across Europe with 244 maize hybrids; (3) assigning individual experiments to scenarios based on environmental conditions as measured in each field experiment; frequencies of temperature scenarios in our experiments corresponded to future heat scenarios (+5°C); (4) analyzing the genetic variation of plant performance for each environmental scenario. Forty-eight quantitative trait loci (QTLs) of yield were identified by association genetics using a multi-environment multi-locus model. Eight and twelve QTLs were associated to tolerances to heat and drought stresses because they were specific to hot and dry scenarios, respectively, with low or even negative allelic effects in favorable scenarios. Twenty-four QTLs improved yield in favorable conditions but showed nonsignificant effects under stress; they were therefore associated with higher sensitivity. Our approach showed a pattern of QTL effects expressed as functions of environmental variables and scenarios, allowing us to suggest hypotheses for mechanisms and candidate genes underlying each QTL. It can be used for assessing the performance of genotypes and the contribution of genomic regions under current and future stress situations and to accelerate breeding for drought-prone environments. PMID:27436830

  9. Delivery of continuously-varying stimuli using channelrhodopsin-2

    PubMed Central

    Tchumatchenko, Tatjana; Newman, Jonathan P.; Fong, Ming-fai; Potter, Steve M.

    2013-01-01

    To study sensory processing, stimuli are delivered to the sensory organs of animals and evoked neural activity is recorded downstream. However, noise and uncontrolled modulatory input can interfere with repeatable delivery of sensory stimuli to higher brain regions. Here we show how channelrhodopsin-2 (ChR2) can be used to deliver continuous, subthreshold, time-varying currents to neurons at any point along the sensory-motor pathway. To do this, we first deduce the frequency response function of ChR2 using a Markov model of channel kinetics. We then confirm ChR2's frequency response characteristics using continuously-varying optical stimulation of neurons that express one of three ChR2 variants. We find that wild-type ChR2 and the E123T/H134R mutant (“ChETA”) can pass continuously-varying subthreshold stimuli with frequencies up to ~70 Hz. Additionally, we find that wild-type ChR2 exhibits a strong resonance at ~6–10 Hz. Together, these results indicate that ChR2-derived optogenetic tools are useful for delivering highly repeatable artificial stimuli that mimic in vivo synaptic bombardment. PMID:24367294

  10. Varying Inundation Regimes Differentially Affect Natural and ...

    EPA Pesticide Factsheets

    Climate change is altering sea-level rise rates and precipitation patterns worldwide. Coastal wetlands are vulnerable to these changes. System responses to stressors are important for resource managers and environmental stewards to understand in order to best manage them. Thin layer sand or sediment application to drowning and eroding marshes is one approach to build elevation and resilience. The above- and below-ground structure, soil carbon dioxide emissions, and pore water constituents in vegetated natural marsh sediments and sand-amended sediments were examined at varying inundation regimes between mean sea level and mean high water (0.82 m NAVD88 to 1.49 m NAVD88) in a field experiment at Laws Point, part of the Plum Island Sound Estuary (MA). Significantly lower salinities, pH, sulfides, phosphates, and ammonium were measured in the sand-amended sediments than in the natural sediments. In natural sediments there was a pattern of increasing salinity with increasing elevation while in the sand-amended sediments the trend was reversed, showing decreasing salinity with increasing elevation. Sulfide concentrations generally increased from low to high inundation with highest concentrations at the highest inundation (i.e., at the lowest elevations). High pore water phosphate concentrations were measured at low elevations in the natural sediments, but the sand-amended treatments had mostly low concentrations of phosphate and no consistent pattern with elevation. A

  11. Serotonin release varies with brain tryptophan levels

    NASA Technical Reports Server (NTRS)

    Schaechter, Judith D.; Wurtman, Richard J.

    1990-01-01

    This study examines directly the effects on serotonin release of varying brain tryptophan levels within the physiologic range. It also addresses possible interactions between tryptophan availability and the frequency of membrane depolarization in controlling serotonin release. We demonstrate that reducing tryptophan levels in rat hypothalamic slices (by superfusing them with medium supplemented with 100 microM leucine) decreases tissue serotonin levels as well as both the spontaneous and the electrically-evoked serotonin release. Conversely, elevating tissue tryptophan levels (by superfusing slices with medium supplemented with 2 microM tryptophan) increases both the tissue serotonin levels and the serotonin release. Serotonin release was found to be affected independently by the tryptophan availability and the frequency of electrical field-stimulation (1-5 Hz), since increasing both variables produced nearly additive increases in release. These observations demonstrate for the first time that both precursor-dependent elevations and reductions in brain serotonin levels produce proportionate changes in serotonin release, and that the magnitude of the tryptophan effect is unrelated to neuronal firing frequency. The data support the hypothesis that serotonin release is proportionate to intracellular serotonin levels.

  12. Rumor Detection over Varying Time Windows.

    PubMed

    Kwon, Sejeong; Cha, Meeyoung; Jung, Kyomin

    2017-01-01

    This study determines the major difference between rumors and non-rumors and explores rumor classification performance levels over varying time windows-from the first three days to nearly two months. A comprehensive set of user, structural, linguistic, and temporal features was examined and their relative strength was compared from near-complete date of Twitter. Our contribution is at providing deep insight into the cumulative spreading patterns of rumors over time as well as at tracking the precise changes in predictive powers across rumor features. Statistical analysis finds that structural and temporal features distinguish rumors from non-rumors over a long-term window, yet they are not available during the initial propagation phase. In contrast, user and linguistic features are readily available and act as a good indicator during the initial propagation phase. Based on these findings, we suggest a new rumor classification algorithm that achieves competitive accuracy over both short and long time windows. These findings provide new insights for explaining rumor mechanism theories and for identifying features of early rumor detection.

  13. TIME-VARYING DYNAMICAL STAR FORMATION RATE

    SciTech Connect

    Lee, Eve J.; Chang, Philip; Murray, Norman

    2015-02-10

    We present numerical evidence of dynamic star formation in which the accreted stellar mass grows superlinearly with time, roughly as t {sup 2}. We perform simulations of star formation in self-gravitating hydrodynamic and magnetohydrodynamic turbulence that is continuously driven. By turning the self-gravity of the gas in the simulations on or off, we demonstrate that self-gravity is the dominant physical effect setting the mass accretion rate at early times before feedback effects take over, contrary to theories of turbulence-regulated star formation. We find that gravitational collapse steepens the density profile around stars, generating the power-law tail on what is otherwise a lognormal density probability distribution function. Furthermore, we find turbulent velocity profiles to flatten inside collapsing regions, altering the size-line width relation. This local flattening reflects enhancements of turbulent velocity on small scales, as verified by changes to the velocity power spectra. Our results indicate that gas self-gravity dynamically alters both density and velocity structures in clouds, giving rise to a time-varying star formation rate. We find that a substantial fraction of the gas that forms stars arrives via low-density flows, as opposed to accreting through high-density filaments.

  14. Proactive inhibitory control varies with task context.

    PubMed

    Wardak, Claire; Ramanoël, Stephen; Guipponi, Olivier; Boulinguez, Philippe; Ben Hamed, Suliann

    2012-12-01

    The goal of executive control is to adjust our behaviour to the environment. It involves not only the continuous planning and adaptation of actions but also the inhibition of inappropriate movements. Recently, a proactive form of inhibitory control has been shown, demonstrating that actions can be withheld, in an uncertain environment, thanks to the proactive locking of the mechanism by which motor commands are triggered (e.g. while waiting at traffic lights in a dense pedestrian zone, one will refrain in anticipation of a brisk acceleration when the green light comes on). However, little is known about this executive function and it remains unclear whether the overall amount of inhibitory control can be modulated as a function of the context. Here, we show that the level of this control varies parametrically as a function of the exogenous and endogenous factors setting the task context. We also show that the level of implemented proactive inhibitory control is dynamically readjusted to match the implicit temporal structure of the environment. These observations are discussed in relation to possible underlying functional substrates and related neurological and psychiatric pathologies.

  15. Rumor Detection over Varying Time Windows

    PubMed Central

    Kwon, Sejeong; Jung, Kyomin

    2017-01-01

    This study determines the major difference between rumors and non-rumors and explores rumor classification performance levels over varying time windows—from the first three days to nearly two months. A comprehensive set of user, structural, linguistic, and temporal features was examined and their relative strength was compared from near-complete date of Twitter. Our contribution is at providing deep insight into the cumulative spreading patterns of rumors over time as well as at tracking the precise changes in predictive powers across rumor features. Statistical analysis finds that structural and temporal features distinguish rumors from non-rumors over a long-term window, yet they are not available during the initial propagation phase. In contrast, user and linguistic features are readily available and act as a good indicator during the initial propagation phase. Based on these findings, we suggest a new rumor classification algorithm that achieves competitive accuracy over both short and long time windows. These findings provide new insights for explaining rumor mechanism theories and for identifying features of early rumor detection. PMID:28081135

  16. Device for varying engine valve timing

    SciTech Connect

    Hampton, K.

    1988-07-05

    A device is described for angularly displacing a camshaft relative to the crankshaft of an IC engine to vary the engine valve timing, comprising; a hub member; means to attach the hub member to the engine crankshaft; a drive member rotatably mounted on the hub member, and means connecting the drive member in driving relationship with the engine crankshaft; an advancing member; a first means interconnecting the advancing member with the hub member affecting limited axial movement of the advancing member relative to the hub member; a second means interconnecting the advancing member with the drive member which upon axial movement of the advancing member causes limited rotation of the drive member relative to the hub member; an annular means mounted on the hub member, the advancing member mounted on the annular means; coacting meshing means formed in part on the annular means for moving the advancing member axially relative to the hub upon limited rotation of the annular means relative to the hub; and a non-rotational retarder means which when actuated applies a retarding torque to the annular means causing limited rotation of the annular means relative to the hub and thus cause the advancing member to move axially of the hub whereby the drive member is moved a limited angular distance relative to the hub member.

  17. Vector curvaton with varying kinetic function

    SciTech Connect

    Dimopoulos, Konstantinos; Karciauskas, Mindaugas; Wagstaff, Jacques M.

    2010-01-15

    A new model realization of the vector curvaton paradigm is presented and analyzed. The model consists of a single massive Abelian vector field, with a Maxwell-type kinetic term. By assuming that the kinetic function and the mass of the vector field are appropriately varying during inflation, it is shown that a scale-invariant spectrum of superhorizon perturbations can be generated. These perturbations can contribute to the curvature perturbation of the Universe. If the vector field remains light at the end of inflation it is found that it can generate substantial statistical anisotropy in the spectrum and bispectrum of the curvature perturbation. In this case the non-Gaussianity in the curvature perturbation is predominantly anisotropic, which will be a testable prediction in the near future. If, on the other hand, the vector field is heavy at the end of inflation then it is demonstrated that particle production is approximately isotropic and the vector field alone can give rise to the curvature perturbation, without directly involving any fundamental scalar field. The parameter space for both possibilities is shown to be substantial. Finally, toy models are presented which show that the desired variation of the mass and kinetic function of the vector field can be realistically obtained, without unnatural tunings, in the context of supergravity or superstrings.

  18. Scrotal abscess: Varied etiology, associations, and management

    PubMed Central

    Ramareddy, Raghu S.; Alladi, Anand

    2016-01-01

    Aim: To report a series of scrotal abscess, a rare problem, their etiology, and management. Materials and Methods: A retrospective study of children who presented with scrotal abscess between January 2010 and March 2015, analyzed with respect to clinical features, pathophysiology of spread and management. Results: Eight infants and a 3-year-old phenotypically male child presented with scrotal abscess as a result of abdominal pathologies which included mixed gonadal dysgenesis (MGD) [1]; three anorectal malformations with ectopic ureter [1], urethral stricture [1], and neurogenic bladder [1]; meconium peritonitis with meconium periorchitis [2], ileal atresia [1], and intra-abdominal abscess [1]; posturethroplasty for Y urethral duplication with metal stenosis [1] and idiopathic pyocele [1]. Transmission of the organism had varied routes include fallopian tube [1], urethra ejaculatory reflux [4], hematogenous [2], and the patent process of vaginalis [2]. Two of the nine required extensive evaluation for further management. Treating the predisposing pathology resolved scrotal abscesses in eight of nine patients, one of whom, required vasectomy additionally. Idiopathic pyocele responded to needle aspiration and antibiotics. Conclusion: Scrotal abscess needs a high index of suspicion for predisposing pathology, especially in infants. Laparoscopy is safe and effective in the management of the MGD and ectopic ureter. PMID:27695207

  19. Stratospheric Impact of Varying Sea Surface Temperatures

    NASA Technical Reports Server (NTRS)

    Newman, Paul A.; Nash, Eric R.; Nielsen, Jon E.; Waugh, Darryn; Pawson, Steven

    2004-01-01

    The Finite-Volume General Circulation Model (FVGCM) has been run in 50 year simulations with the: 1) 1949-1999 Hadley Centre sea surface temperatures (SST), and 2) a fixed annual cycle of SSTs. In this presentation we first show that the 1949-1999 FVGCM simulation produces a very credible stratosphere in comparison to an NCEP/NCAR reanalysis climatology. In particular, the northern hemisphere has numerous major and minor stratospheric warming, while the southern hemisphere has only a few over the 50-year simulation. During the northern hemisphere winter, temperatures are both warmer in the lower stratosphere and the polar vortex is weaker than is found in the mid-winter southern hemisphere. Mean temperature differences in the lower stratosphere are shown to be small (less than 2 K), and planetary wave forcing is found to be very consistent with the climatology. We then will show the differences between our varying SST simulation and the fixed SST simulation in both the dynamics and in two parameterized trace gases (ozone and methane). In general, differences are found to be small, with subtle changes in planetary wave forcing that lead to reduced temperatures in the SH and increased temperatures in the NH.

  20. Wide-Field Plate Database

    NASA Astrophysics Data System (ADS)

    Tsvetkov, M. K.; Stavrev, K. Y.; Tsvetkova, K. P.; Semkov, E. H.; Mutatov, A. S.

    The Wide-Field Plate Database (WFPDB) and the possibilities for its application as a research tool in observational astronomy are presented. Currently the WFPDB comprises the descriptive data for 400 000 archival wide field photographic plates obtained with 77 instruments, from a total of 1 850 000 photographs stored in 269 astronomical archives all over the world since the end of last century. The WFPDB is already accessible for the astronomical community, now only in batch mode through user requests sent by e-mail. We are working on on-line interactive access to the data via INTERNET from Sofia and parallel from the Centre de Donnees Astronomiques de Strasbourg. (Initial information can be found on World Wide Web homepage URL http://www.wfpa.acad.bg.) The WFPDB may be useful in studies of a variety of astronomical objects and phenomena, andespecially for long-term investigations of variable objects and for multi-wavelength research. We have analysed the data in the WFPDB in order to derive the overall characteristics of the totality of wide-field observations, such as the sky coverage, the distributions by observation time and date, by spectral band, and by object type. We have also examined the totality of wide-field observations from point of view of their quality, availability and digitisation. The usefulness of the WFPDB is demonstrated by the results of identification and investigation of the photometrical behaviour of optical analogues of gamma-ray bursts.

  1. Development of a Passively Varying Pitch Propeller

    NASA Astrophysics Data System (ADS)

    Heinzen, Stearns Beamon

    Small general aviation aircraft and unmanned aerial systems are often equipped with sophisticated navigation, control, and other avionics, but retain propulsion systems consisting of retrofitted radio control and ultralight equipment. Consequently, new high performance airframes often rely on relatively primitive propulsive technology. This trend is beginning to shift with recent advances in small turboprop engines, fuel injected reciprocating engines, and improved electric technologies. Although these systems are technologically advanced, they are often paired with standard fixed pitch propellers. To fully realize the potential of these aircraft and the new generation of engines, small propellers which can efficiently transmit power over wide flight envelopes and a variety of power settings must be developed. This work demonstrates a propeller which passively adjusts to incoming airflow at a low penalty to aircraft weight and complexity. This allows the propeller to operate in an efficient configuration over a wide flight envelope, and can prevent blade stall in low-velocity / highly-loaded thrust cases and over-speeding at high flight speeds. The propeller incorporates blades which pivot freely on a radial axis and are aerodynamically tailored to attain and maintain a pitch angle yielding favorable local blade angles of attack, matched to changing inflow conditions. This blade angle is achieved through the use of reflexed airfoils designed for a positive pitching moment, comparable to those used on many tailless flying wings. By setting the axis of rotation at a point forward of the blade aerodynamic center, the blades will naturally adjust to a predetermined positive lift 'trim' condition. Then, as inflow conditions change, the blade angle will automatically pivot to maintain the same angle with respect to incoming air. Computational, wind tunnel, and flight test results indicate that the extent of efficient propeller operation can be increased dramatically as

  2. Process model for ammonia volatilization from anaerobic swine lagoons incorporating varying wind speeds and biogas bubbling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization from treatment lagoons varies widely with the total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model integrating ammonia ...

  3. Debating Life on Mars: The Knowledge Integration Environment (KIE) in Varied School Settings.

    ERIC Educational Resources Information Center

    Shear, Linda

    Technology-enabled learning environments are beginning to come of age. Tools and frameworks are now available that have been shown to improve learning and are being deployed more widely in varied school settings. Teachers are now faced with the formidable challenge of integrating these promising new environments with the everyday context in which…

  4. Immobilization of lipase from Mucor miehei and Rhizopus oryzae into mesoporous silica--the effect of varied particle size and morphology.

    PubMed

    Gustafsson, Hanna; Johansson, Emma M; Barrabino, Albert; Odén, Magnus; Holmberg, Krister

    2012-12-01

    Immobilization of enzymes usually improves the recyclability and stability and can sometimes also improve the activity compared to enzymes free in solution. Mesoporous silica is a widely studied material as host for immobilized enzymes because of its large internal surface area and tunable pores. It has previously been shown that the pore size is critical both for the loading capacity and for the enzymatic activity; however, less focus has been given to the influence of the particle size. In this work the effect of particle size and particle morphology on the immobilization of lipase from Mucor miehei and Rhizopus oryzae have been investigated. Three kinds of mesoporous silica, all with 9 nm pores but with varying particle size (1000 nm, 300 nm and 40 nm) have been synthesized and were used as host for the lipases. The two lipases, which have the same molecular size but widely different isoelectric points, were immobilized into the silica particles at varied pH values within the interval 5-8. The 300 nm particles were proven to be the most suitable carrier with respect to specific activity for both enzymes. The lipase from M. miehei was more than four times as active when immobilized at pH 8 compared to free in solution whereas the difference was less pronounced for the R. oryzae lipase.

  5. A melanocortin 1 receptor allele suggests varying pigmentation among Neanderthals.

    PubMed

    Lalueza-Fox, Carles; Römpler, Holger; Caramelli, David; Stäubert, Claudia; Catalano, Giulio; Hughes, David; Rohland, Nadin; Pilli, Elena; Longo, Laura; Condemi, Silvana; de la Rasilla, Marco; Fortea, Javier; Rosas, Antonio; Stoneking, Mark; Schöneberg, Torsten; Bertranpetit, Jaume; Hofreiter, Michael

    2007-11-30

    The melanocortin 1 receptor (MC1R) regulates pigmentation in humans and other vertebrates. Variants of MC1R with reduced function are associated with pale skin color and red hair in humans of primarily European origin. We amplified and sequenced a fragment of the MC1R gene (mc1r) from two Neanderthal remains. Both specimens have a mutation that was not found in approximately 3700 modern humans analyzed. Functional analyses show that this variant reduces MC1R activity to a level that alters hair and/or skin pigmentation in humans. The impaired activity of this variant suggests that Neanderthals varied in pigmentation levels, potentially on the scale observed in modern humans. Our data suggest that inactive MC1R variants evolved independently in both modern humans and Neanderthals.

  6. Attitudes as Object-Evaluation Associations of Varying Strength

    PubMed Central

    Fazio, Russell H.

    2009-01-01

    Historical developments regarding the attitude concept are reviewed, and set the stage for consideration of a theoretical perspective that views attitude, not as a hypothetical construct, but as evaluative knowledge. A model of attitudes as object-evaluation associations of varying strength is summarized, along with research supporting the model’s contention that at least some attitudes are represented in memory and activated automatically upon the individual’s encountering the attitude object. The implications of the theoretical perspective for a number of recent discussions related to the attitude concept are elaborated. Among these issues are the notion of attitudes as “constructions,” the presumed malleability of automatically-activated attitudes, correspondence between implicit and explicit measures of attitude, and postulated dual or multiple attitudes. PMID:19424447

  7. Audibility of time-varying signals in time-varying backgrounds: Model and data

    NASA Astrophysics Data System (ADS)

    Moore, Brian C. J.; Glasberg, Brian R.

    2004-05-01

    We have described a model for calculating the partial loudness of a steady signal in the presence of a steady background sound [Moore et al., J. Audio Eng. Soc. 45, 224-240 (1997)]. We have also described a model for calculating the loudness of time-varying signals [B. R. Glasberg and B. C. J. Moore, J. Audio Eng. Soc. 50, 331-342 (2002)]. These two models have been combined to allow calculation of the partial loudness of a time-varying signal in the presence of a time-varying background. To evaluate the model, psychometric functions for the detection of a variety of time-varying signals (e.g., telephone ring tones) have been measured in a variety of background sounds sampled from everyday listening situations, using a two-alternative forced-choice task. The different signals and backgrounds were interleaved, to create stimulus uncertainty, as would occur in everyday life. The data are used to relate the detectability index, d', to the calculated partial loudness. In this way, the model can be used to predict the detectability of any signal, based on its calculated partial loudness. [Work supported by MRC (UK) and by Nokia.

  8. How specific halide adsorption varies hydrophobic interactions.

    PubMed

    Stock, Philipp; Müller, Melanie; Utzig, Thomas; Valtiner, Markus

    2016-03-11

    Hydrophobic interactions (HI) are driven by the water structure around hydrophobes in aqueous electrolytes. How water structures at hydrophobic interfaces and how this influences the HI was subject to numerous studies. However, the effect of specific ion adsorption on HI and hydrophobic interfaces remains largely unexplored or controversial. Here, the authors utilized atomic force microscopy force spectroscopy at well-defined nanoscopic hydrophobic interfaces to experimentally address how specific ion adsorption of halide ions as well as NH4 (+), Cs(+), and Na(+) cations alters interaction forces across hydrophobic interfaces. Our data demonstrate that iodide adsorption at hydrophobic interfaces profoundly varies the hydrophobic interaction potential. A long-range and strong hydration repulsion at distances D > 3 nm, is followed by an instability which could be explained by a subsequent rapid ejection of adsorbed iodides from approaching hydrophobic interfaces. In addition, the authors find only a weakly pronounced influence of bromide, and as expected no influence of chloride. Also, all tested cations do not have any significant influence on HI. Complementary, x-ray photoelectron spectroscopy and quartz-crystal-microbalance with dissipation monitoring showed a clear adsorption of large halide ions (Br(-)/I(-)) onto hydrophobic self-assembled monolayers (SAMs). Interestingly, iodide can even lead to a full disintegration of SAMs due to specific and strong interactions of iodide with gold. Our data suggest that hydrophobic surfaces are not intrinsically charged negatively by hydroxide adsorption, as it was generally believed. Hydrophobic surfaces rather interact strongly with negatively charged large halide ions, leading to a surface charging and significant variation of interaction forces.

  9. Operator strategies under varying conditions of workload

    NASA Technical Reports Server (NTRS)

    Arnegard, Ruth J.

    1991-01-01

    An attempt was made to operationally define and measure strategic behavior in a complex multiple task environment. The Multi-Attribute Task battery was developed to simulate various aspects of flight and consisted of an auditory communication task, monitoring tasks, a tracking tasks, a resource management task which allowed a wide range of responding patterns, and a scheduling window which allowed operators to predict changes in workload. This battery was validated for its sensitivity to strategic behavior, and baseline measures for each individual task were collected. Twenty-four undergraduate and graduate students then performed the battery for four 64 minute sessions which took place over a period of 2 days. Each subject performed the task battery under four levels of workload, which were presented for equal lengths of time during all four sessions. Results indicated that in general, performance improves as a function of experience with the battery, but that performance decreased as workload level increased. The data also showed that subjects developed strategies for responding to the resource management task which allowed them to manage the high workload levels more efficiently. This particular strategy developed over time but was also associated with errors of complacency. These results are presented along with implications for the aviation field and areas of future research.

  10. Wide field of view telescope

    DOEpatents

    Ackermann, Mark R.; McGraw, John T.; Zimmer, Peter C.

    2008-01-15

    A wide field of view telescope having two concave and two convex reflective surfaces, each with an aspheric surface contour, has a flat focal plane array. Each of the primary, secondary, tertiary, and quaternary reflective surfaces are rotationally symmetric about the optical axis. The combination of the reflective surfaces results in a wide field of view in the range of approximately 3.8.degree. to approximately 6.5.degree.. The length of the telescope along the optical axis is approximately equal to or less than the diameter of the largest of the reflective surfaces.

  11. Cydonia: Wide Angle Color Image

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    Although the resolution of the MOC wide angle cameras is too low to tell much about the geomorphology of the Cydonia region, the images from the red and blue wide angle cameras provide us with two types of information that is of interest in their own right: color and stereoscopic data. Above are a color view and a stereoscopic anaglyph rendition of Geodesy Campaign images acquired by MGS MOC in May 1999. To view the stereo image, you need red/blue '3-D' glasses.

  12. World Wide Web Homepage Design.

    ERIC Educational Resources Information Center

    Tillman, Michael L.

    This paper examines hypermedia design and draws conclusions about how educational research and theory applies to various aspects of World Wide Web (WWW) homepage design. "Hypermedia" is defined as any collection of information which may be textual, graphical, visual, or auditory in nature and which may be accessed via a nonlinear route.…

  13. Profiling genome-wide DNA methylation.

    PubMed

    Yong, Wai-Shin; Hsu, Fei-Man; Chen, Pao-Yang

    2016-01-01

    DNA methylation is an epigenetic modification that plays an important role in regulating gene expression and therefore a broad range of biological processes and diseases. DNA methylation is tissue-specific, dynamic, sequence-context-dependent and trans-generationally heritable, and these complex patterns of methylation highlight the significance of profiling DNA methylation to answer biological questions. In this review, we surveyed major methylation assays, along with comparisons and biological examples, to provide an overview of DNA methylation profiling techniques. The advances in microarray and sequencing technologies make genome-wide profiling possible at a single-nucleotide or even a single-cell resolution. These profiling approaches vary in many aspects, such as DNA input, resolution, genomic region coverage, and bioinformatics analysis, and selecting a feasible method requires knowledge of these methods. We first introduce the biological background of DNA methylation and its pattern in plants, animals and fungi. We present an overview of major experimental approaches to profiling genome-wide DNA methylation and hydroxymethylation and then extend to the single-cell methylome. To evaluate these methods, we outline their strengths and weaknesses and perform comparisons across the different platforms. Due to the increasing need to compute high-throughput epigenomic data, we interrogate the computational pipeline for bisulfite sequencing data and also discuss the concept of identifying differentially methylated regions (DMRs). This review summarizes the experimental and computational concepts for profiling genome-wide DNA methylation, followed by biological examples. Overall, this review provides researchers useful guidance for the selection of a profiling method suited to specific research questions.

  14. Modeling Motu Profile Response to Varying Wave and Storm Climate

    NASA Astrophysics Data System (ADS)

    Ortiz, A. C.; Ashton, A. D.; Donnelly, J. P.

    2014-12-01

    The atolls of the Pacific Ocean are low-lying landforms (less than 5m in elevation), typically consisting of reef-building corals often mounted by subaerial islets, or motu, which encircle a central lagoon. These motu, perched atop old coral reefs, typically consist of sand and gravel, and are sometimes anchored by relict geologic features (highstand coral reefs). Despite the vital role these islets play as home to terrestrial ecosystems and human infrastructure, the morphologic processes responsible for their formation and maintenance remain poorly understood. For example, although extreme events are hypothesized as a formation mechanism, motu are found in regions where hurricanes or tropical cyclones rarely occur and across varying storm gradients and frequency tracks. Here we use hydrodynamic and event-based morphodynamic modeling to better understand the role of storm events on the formation and evolution of motu. Using XBeach, a two-dimensional model of infragravity wave propagation and sediment transport, coupled with the coastal wave model, SWAN (Simulating WAves Nearshore), we simulate the hydrodynamic and morphodynamic impacts of storm events on the nearshore, beach, and backbarrier portions of atolls. We investigate the effect of different representative profile morphology, for example motu height or the distance from the reef edge to the motu, on storm response. We further test the effect of storm intensity and inundation scenarios (i.e. difference in elevated water levels of the lagoon and ocean) on storm hydrodynamics and morphologic change. Model scenarios are informed and compared to basin-wide analysis of the variation of atoll and motu characteristics, such as reef width, motu width, and motu spacing across the Pacific Ocean. Atoll morphologies and storm responses are affected by both geographic location and, locally, the shoreline orientation (compared to storm tracks). Combining these different model scenarios with measured morphometrics allows

  15. How Does the Sun's Spectrum Vary?

    NASA Technical Reports Server (NTRS)

    Lean, Judith L.; DeLand, Matthew T.

    2011-01-01

    Recent observations made by the Spectral Irradiance Monitor (SIM) on the Solar Radiation and Climate Experiment (SORCE) spacecraft suggest that the Sun's visible and infrared spectral irradiance increased from 2004 to 2008, even as the total solar irradiance measured simultaneously by SORCE's Total Irradiance Monitor (TIM) decreased. As well, solar ultraviolet (UV) irradiance decreased 3 to 10 times more than expected from prior observations and model calculations of the known effects of sunspot and facular solar features. Analysis of the SIM spectral irradiance observations during the solar minimum epoch of 2008, when solar activity was essentially invariant, exposes trends in the SIM observations relative to both total solar irradiance and solar activity that are unlikely solar in origin. We suggest that the SIM's radically different solar variability characterization is a consequence of undetected instrument sensitivity drifts, not true solar spectrum changes. It is thus doubtful that simulations of climate and atmospheric change using SIM measurements are indicative of real behavior in the Earth's climate and atmosphere.

  16. Lichen Persistence and Recovery in Response to Varied Volcanic Disturbances

    NASA Astrophysics Data System (ADS)

    Nelson, P.; Wheeler, T. B.

    2015-12-01

    Volcanic eruptions produce many ecological disturbances that structure vegetation. While lichens are sensitive to disturbances, little is known about their responses to volcanic disturbances, except for colonization of lava. We examined lichen community responses through time to different disturbances produced by the May 1, 2008 eruption of Volcan Chaiten in south-central Chile. Pre-eruption vegetation near the volcano was old-growth Valdivian temperate rainforest dominated by closed-canopy Nothofagus sp... In 2012, we installed thirteen 1-acre plots across volcanic disturbance zones on which a time-constrained search was done for all macrolichen species, each of which was assigned an approximate log10 categorical abundance. We also installed a 0.2 m2 quadrat on two representative trees per plot for repeat photography of lichen cover. We remeasured at least one plot per disturbance zone in 2014 and re-photographed tree quadrats in 2013 and 2014. We then analyzed species composition and abundance differences among disturbance zones. In 2012, the blast (pyroclastic density flow), scorch (standing scorched forest at the edge of the blast) and deep tephra (>10 cm) zones had the lowest lichen species richness (5-13 species), followed by reference (unimpacted) and shallow (<10 cm) tephra (17-20 species). Gravel rain (preexisting rock ejected by eruption initiation), gravel rain + pumice and flooded forests (fluvially reworked volcanic material entrained by heavy rains) were species-rich (25-42 species). In 2014, the blast and deep tephra had regained 2-3 times the number of lichen species since 2012 while the light tephra and reference were essentially unchanged. Gravel rain, gravel rain + pumice and flooded forest plots all had about the same number of species in 2014 as 2012. Lichen colonization and growth in tree quadrats varied widely, from very little colonization in the blast to prolific colonization in the gravel rain + pumice zone. Lichen's varied responses to

  17. JOINT STRUCTURE SELECTION AND ESTIMATION IN THE TIME-VARYING COEFFICIENT COX MODEL

    PubMed Central

    Xiao, Wei; Lu, Wenbin; Zhang, Hao Helen

    2016-01-01

    Time-varying coefficient Cox model has been widely studied and popularly used in survival data analysis due to its flexibility for modeling covariate effects. It is of great practical interest to accurately identify the structure of covariate effects in a time-varying coefficient Cox model, i.e. covariates with null effect, constant effect and truly time-varying effect, and estimate the corresponding regression coefficients. Combining the ideas of local polynomial smoothing and group nonnegative garrote, we develop a new penalization approach to achieve such goals. Our method is able to identify the underlying true model structure with probability tending to one and simultaneously estimate the time-varying coefficients consistently. The asymptotic normalities of the resulting estimators are also established. We demonstrate the performance of our method using simulations and an application to the primary biliary cirrhosis data. PMID:27540275

  18. Hydroquinone–pyrrole dyads with varied linkers

    PubMed Central

    Huang, Hao; Karlsson, Christoffer; Strømme, Maria; Sjödin, Martin

    2016-01-01

    Summary A series of pyrroles functionalized in the 3-position with p-dimethoxybenzene via various linkers (CH2, CH2CH2, CH=CH, C≡C) has been synthesized. Their electronic properties have been deduced from 1H NMR, 13C NMR, and UV–vis spectra to detect possible interactions between the two aromatic subunits. The extent of conjugation between the subunits is largely controlled by the nature of the linker, with the largest conjugation found with the trans-ethene linker and the weakest with the aliphatic linkers. DFT calculations revealed substantial changes in the HOMO–LUMO gap that correlated with the extent of conjugation found experimentally. The results of this work are expected to open up for use of the investigated compounds as components of redox-active materials in sustainable, organic electrical energy storage devices. PMID:26877811

  19. Wide Bandgap Extrinsic Photoconductive Switches

    SciTech Connect

    Sullivan, James S.

    2012-01-20

    Photoconductive semiconductor switches (PCSS) have been investigated since the late 1970s. Some devices have been developed that withstand tens of kilovolts and others that switch hundreds of amperes. However, no single device has been developed that can reliably withstand both high voltage and switch high current. Yet, photoconductive switches still hold the promise of reliable high voltage and high current operation with subnanosecond risetimes. Particularly since good quality, bulk, single crystal, wide bandgap semiconductor materials have recently become available. In this chapter we will review the basic operation of PCSS devices, status of PCSS devices and properties of the wide bandgap semiconductors 4H-SiC, 6H-SiC and 2H-GaN.

  20. Enterprise-wide worklist management.

    PubMed

    Locko, Roberta C; Blume, Hartwig; Goble, John C

    2002-01-01

    Radiologists in multi-facility health care delivery networks must serve not only their own departments but also departments of associated clinical facilities. We describe our experience with a picture archiving and communication system (PACS) implementation that provides a dynamic view of relevant radiological workload across multiple facilities. We implemented a distributed query system that permits management of enterprise worklists based on modality, body part, exam status, and other criteria that span multiple compatible PACSs. Dynamic worklists, with lesser flexibility, can be constructed if the incompatible PACSs support specific DICOM functionality. Enterprise-wide worklists were implemented across Generations Plus/Northern Manhattan Health Network, linking radiology departments of three hospitals (Harlem, Lincoln, and Metropolitan) with 1465 beds and 4260 ambulatory patients per day. Enterprise-wide, dynamic worklist management improves utilization of radiologists and enhances the quality of care across large multi-facility health care delivery organizations. Integration of other workflow-related components remain a significant challenge.

  1. Wide Bandgap Extrinsic Photoconductive Switches

    SciTech Connect

    Sullivan, James S.

    2013-07-03

    Semi-insulating Gallium Nitride, 4H and 6H Silicon Carbide are attractive materials for compact, high voltage, extrinsic, photoconductive switches due to their wide bandgap, high dark resistance, high critical electric field strength and high electron saturation velocity. These wide bandgap semiconductors are made semi-insulating by the addition of vanadium (4H and 6HSiC) and iron (2H-GaN) impurities that form deep acceptors. These deep acceptors trap electrons donated from shallow donor impurities. The electrons can be optically excited from these deep acceptor levels into the conduction band to transition the wide bandgap semiconductor materials from a semi-insulating to a conducting state. Extrinsic photoconductive switches with opposing electrodes have been constructed using vanadium compensated 6H-SiC and iron compensated 2H-GaN. These extrinsic photoconductive switches were tested at high voltage and high power to determine if they could be successfully used as the closing switch in compact medical accelerators.

  2. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control.

    PubMed

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-02-20

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson's Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

  3. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

    PubMed Central

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-01-01

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity. PMID:28218249

  4. Varied line-space gratings: past, present and future

    SciTech Connect

    Hettrick, M.C.

    1985-08-01

    A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely, the so-called ''holographic'' grating (formed by the interfering waves of coherent visible light), although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast, a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include: (1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical de-multiplexers, (2) flat-field grazing incidence concave gratings for plasma diagnostics, (3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, (4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and (5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. The author discusses the history of VLS gratings, their present applications, and their potential in the future. 61 refs., 24 figs.

  5. NARAC SOFTWARE QUALITY ASSURANCE: ADAPTING FORMALISM TO MEET VARYING NEEDS

    SciTech Connect

    Walker, H; Nasstrom, J S; Homann, S G

    2007-11-20

    The National Atmospheric Release Advisory Center (NARAC) provides tools and services that predict and map the spread of hazardous material accidentally or intentionally released into the atmosphere. NARAC is a full function system that can meet a wide range of needs with a particular focus on emergency response. The NARAC system relies on computer software in the form of models of the atmosphere and related physical processes supported by a framework for data acquisition and management, user interface, visualization, communications and security. All aspects of the program's operations and research efforts are predicated to varying degrees on the reliable and correct performance of this software. Consequently, software quality assurance (SQA) is an essential component of the NARAC program. The NARAC models and system span different levels of sophistication, fidelity and complexity. These different levels require related but different approaches to SQA. To illustrate this, two different levels of software complexity are considered in this paper. As a relatively simple example, the SQA procedures that are being used for HotSpot, a straight-line Gaussian model focused on radiological releases, are described. At the other extreme, the SQA issues that must be considered and balanced for the more complex NARAC system are reviewed.

  6. Varied Line-Space Gratings: Past, Present And Future

    NASA Astrophysics Data System (ADS)

    Hettrick, Michael C.

    1986-05-01

    A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely the so-called "holographic" grating ( formed by the interfering waves of coherent visible light ) , although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include 1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical demultiplexers, 2) flat-field grazing incidence concave gratings for plasma diagnostics, 3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, 4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and 5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. I discuss the history of VLS gratings, their present applications and their potential in the future.

  7. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

    NASA Astrophysics Data System (ADS)

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-02-01

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

  8. Wet-spinnability and crosslinked fibre properties of two collagen polypeptides with varied molecular weight.

    PubMed

    Tronci, Giuseppe; Kanuparti, Ramya Sri; Arafat, M Tarik; Yin, Jie; Wood, David J; Russell, Stephen J

    2015-11-01

    The formation of naturally derived materials with wet stable fibrous architectures is paramount in order to mimic the features of tissues at the molecular and microscopic scale. Here, we investigated the formation of wet-spun fibres based on collagen-derived polypeptides with comparable chemical composition and varied molecular weight. Gelatin and hydrolysed fish collagen (HFC) were selected as widely available linear amino-acidic chains of high and low molecular weight, respectively, and functionalised in the wet-spun fibre state in order to preserve the material geometry in physiological conditions. Wet-spun fibre diameter and morphology were dramatically affected depending on the polypeptide molecular weight, wet-spinning solvent (i.e. 2,2,2-trifluoroethanol and dimethyl sulfoxide) and coagulating medium (i.e. acetone and ethanol), resulting in either bulky or porous internal geometry. Dry-state tensile moduli were significantly enhanced in gelatin and HFC samples following covalent crosslinking with activated 1,3-phenylenediacetic acid (Ph) (E: 726±43-844±85MPa), compared to samples crosslinked via intramolecular carbodiimide-mediated condensation reaction (E: 588±38MPa). Resulting fibres displayed a dry diameter in the range of 238±18-355±28μm and proved to be mechanically stable (E: 230kPa) following equilibration with PBS, whilst a nearly complete degradation was observed after 5-day incubation in physiological conditions.

  9. Modeling the chemotactic response of Escherichia coli to time-varying stimuli

    PubMed Central

    Tu, Yuhai; Shimizu, Thomas S.; Berg, Howard C.

    2008-01-01

    In their natural environment, cells need to extract useful information from complex temporal signals that vary over a wide range of intensities and time scales. Here, we study how such signals are processed by Escherichia coli during chemotaxis by developing a general theoretical model based on receptor adaptation and receptor–receptor cooperativity. Measured responses to various monotonic, oscillatory, and impulsive stimuli are all explained consistently by the underlying adaptation kinetics within this model. For exponential ramp signals, an analytical solution is discovered that reveals a remarkable connection between the dependence of kinase activity on the exponential ramp rate and the receptor methylation rate function. For exponentiated sine-wave signals, spectral analysis shows that the chemotaxis pathway acts as a lowpass filter for the derivative of the signal with the cutoff frequency determined by an intrinsic adaptation time scale. For large step stimuli, we find that the recovery time is determined by the constant maximum methylation rate, which provides a natural explanation for the observed recovery time additivity. Our model provides a quantitative system-level description of the chemotaxis signaling pathway and can be used to predict E. coli chemotaxis responses to arbitrary temporal signals. This model of the receptor system reveals the molecular origin of Weber's law in bacterial chemotaxis. We further identify additional constraints required to account for the related observation that the output of this pathway is constant under exponential ramp stimuli, a feature that we call “logarithmic tracking.” PMID:18812513

  10. Wide-field wide-band Interferometric Imaging: The WB A-Projection and Hybrid Algorithms

    NASA Astrophysics Data System (ADS)

    Bhatnagar, S.; Rau, U.; Golap, K.

    2013-06-01

    Variations of the antenna primary beam (PB) pattern as a function of time, frequency, and polarization form one of the dominant direction-dependent effects at most radio frequency bands. These gains may also vary from antenna to antenna. The A-Projection algorithm, published earlier, accounts for the effects of the narrow-band antenna PB in full polarization. In this paper, we present the wide-band A-Projection algorithm (WB A-Projection) to include the effects of wide bandwidth in the A-term itself and show that the resulting algorithm simultaneously corrects for the time, frequency, and polarization dependence of the PB. We discuss the combination of the WB A-Projection and the multi-term multi-frequency synthesis (MT-MFS) algorithm for simultaneous mapping of the sky brightness distribution and the spectral index distribution across a wide field of view. We also discuss the use of the narrow-band A-Projection algorithm in hybrid imaging schemes that account for the frequency dependence of the PB in the image domain.

  11. WIDE-FIELD WIDE-BAND INTERFEROMETRIC IMAGING: THE WB A-PROJECTION AND HYBRID ALGORITHMS

    SciTech Connect

    Bhatnagar, S.; Rau, U.; Golap, K. E-mail: rurvashi@nrao.edu

    2013-06-20

    Variations of the antenna primary beam (PB) pattern as a function of time, frequency, and polarization form one of the dominant direction-dependent effects at most radio frequency bands. These gains may also vary from antenna to antenna. The A-Projection algorithm, published earlier, accounts for the effects of the narrow-band antenna PB in full polarization. In this paper, we present the wide-band A-Projection algorithm (WB A-Projection) to include the effects of wide bandwidth in the A-term itself and show that the resulting algorithm simultaneously corrects for the time, frequency, and polarization dependence of the PB. We discuss the combination of the WB A-Projection and the multi-term multi-frequency synthesis (MT-MFS) algorithm for simultaneous mapping of the sky brightness distribution and the spectral index distribution across a wide field of view. We also discuss the use of the narrow-band A-Projection algorithm in hybrid imaging schemes that account for the frequency dependence of the PB in the image domain.

  12. Optical waveguide device with an adiabatically-varying width

    DOEpatents

    Watts; Michael R. , Nielson; Gregory N.

    2011-05-10

    Optical waveguide devices are disclosed which utilize an optical waveguide having a waveguide bend therein with a width that varies adiabatically between a minimum value and a maximum value of the width. One or more connecting members can be attached to the waveguide bend near the maximum value of the width thereof to support the waveguide bend or to supply electrical power to an impurity-doped region located within the waveguide bend near the maximum value of the width. The impurity-doped region can form an electrical heater or a semiconductor junction which can be activated with a voltage to provide a variable optical path length in the optical waveguide. The optical waveguide devices can be used to form a tunable interferometer (e.g. a Mach-Zehnder interferometer) which can be used for optical modulation or switching. The optical waveguide devices can also be used to form an optical delay line.

  13. Genome-Wide Scan Reveals Mutation Associated with Melanoma

    MedlinePlus

    ... historical) Genome-Wide Scan Reveals Mutation Associated with Melanoma A team of international researchers supported by the ... when they divide and grow uncontrollably, develop into melanoma. Also, MITF activity is known to be amplified ...

  14. Tropical cyclone cooling combats region-wide coral bleaching.

    PubMed

    Carrigan, Adam D; Puotinen, Marji

    2014-05-01

    Coral bleaching has become more frequent and widespread as a result of rising sea surface temperature (SST). During a regional scale SST anomaly, reef exposure to thermal stress is patchy in part due to physical factors that reduce SST to provide thermal refuge. Tropical cyclones (TCs - hurricanes, typhoons) can induce temperature drops at spatial scales comparable to that of the SST anomaly itself. Such cyclone cooling can mitigate bleaching across broad areas when well-timed and appropriately located, yet the spatial and temporal prevalence of this phenomenon has not been quantified. Here, satellite SST and historical TC data are used to reconstruct cool wakes (n=46) across the Caribbean during two active TC seasons (2005 and 2010) where high thermal stress was widespread. Upon comparison of these datasets with thermal stress data from Coral Reef Watch and published accounts of bleaching, it is evident that TC cooling reduced thermal stress at a region-wide scale. The results show that during a mass bleaching event, TC cooling reduced thermal stress below critical levels to potentially mitigate bleaching at some reefs, and interrupted natural warming cycles to slow the build-up of thermal stress at others. Furthermore, reconstructed TC wave damage zones suggest that it was rare for more reef area to be damaged by waves than was cooled (only 12% of TCs). Extending the time series back to 1985 (n = 314), we estimate that for the recent period of enhanced TC activity (1995-2010), the annual probability that cooling and thermal stress co-occur is as high as 31% at some reefs. Quantifying such probabilities across the other tropical regions where both coral reefs and TCs exist is vital for improving our understanding of how reef exposure to rising SSTs may vary, and contributes to a basis for targeting reef conservation.

  15. Prostate Cancer Treatments Have Varying Side Effects, Study Shows

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_164200.html Prostate Cancer Treatments Have Varying Side Effects, Study Shows Even ' ... News) -- The long-term side effects of different prostate cancer treatments vary -- and knowing that may help men ...

  16. Wide-range voltage modulation

    SciTech Connect

    Rust, K.R.; Wilson, J.M.

    1992-06-01

    The Superconducting Super Collider`s Medium Energy Booster Abort (MEBA) kicker modulator will supply a current pulse to the abort magnets which deflect the proton beam from the MEB ring into a designated beam stop. The abort kicker will be used extensively during testing of the Low Energy Booster (LEB) and the MEB rings. When the Collider is in full operation, the MEBA kicker modulator will abort the MEB beam in the event of a malfunction during the filling process. The modulator must generate a 14-{mu}s wide pulse with a rise time of less than 1 {mu}s, including the delay and jitter times. It must also be able to deliver a current pulse to the magnet proportional to the beam energy at any time during ramp-up of the accelerator. Tracking the beam energy, which increases from 12 GeV at injection to 200 GeV at extraction, requires the modulator to operate over a wide range of voltages (4 kV to 80 kV). A vacuum spark gap and a thyratron have been chosen for test and evaluation as candidate switches for the abort modulator. Modulator design, switching time delay, jitter and pre-fire data are presented.

  17. Wide swath imaging spectrometer utilizing a multi-modular design

    DOEpatents

    Chrisp, Michael P.

    2010-10-05

    A wide swath imaging spectrometer utilizing an array of individual spectrometer modules in the telescope focal plane to provide an extended field of view. The spectrometer modules with their individual detectors are arranged so that their slits overlap with motion on the scene providing contiguous spatial coverage. The number of modules can be varied to take full advantage of the field of view available from the telescope.

  18. Comparison of Linear Microinstability Calculations of Varying Input Realism

    SciTech Connect

    G. Rewoldt

    2003-09-08

    The effect of varying ''input realism'' or varying completeness of the input data for linear microinstability calculations, in particular on the critical value of the ion temperature gradient for the ion temperature gradient mode, is investigated using gyrokinetic and gyrofluid approaches. The calculations show that varying input realism can have a substantial quantitative effect on the results.

  19. Ekman Spiral in Horizontally Inhomogeneous Ocean with Varying Eddy Viscosity

    DTIC Science & Technology

    2015-01-01

    1 Ekman Spiral in Horizontally Inhomogeneous Ocean with Varying Eddy Viscosity ...in Horizontally Inhomogeneous Ocean with Varying Eddy Viscosity 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...generated by surface wind stress with constant eddy viscosity in homogeneous ocean. In real oceans, the eddy viscosity varies due to turbulent mixing

  20. Activity correlations between on-like and off-like cells of the rostral ventromedial medulla and simultaneously recorded wide-dynamic-range neurons of the spinal dorsal horn in rats.

    PubMed

    Salas, Rafael; Ramirez, Karla; Vanegas, Horacio; Vazquez, Enrique

    2016-12-01

    Considerable evidence supports the notion that on- and off-cells of the rostral ventromedial medulla (RVM) facilitate and depress, respectively, spinal nociceptive transmission. This notion stems from a covariation of on- or off-cell activities and spinal nocifensive reflexes. Such covariation could theoretically be due to their independently responding to a common source, or to an RVM-derived modulation of ventral horn neurons. Here, we tested whether on- and off-cells indeed modulate spinal nociceptive neurons. In deeply anesthetized rats, unitary recordings were simultaneously made from an RVM on-like or off-like cell and a spinal nociceptive neuron that shared a receptive field (RF) at a hind paw. Action potential firing in RVM/spinal neuron pairs was highly correlated, positively for on-like cells and negatively for off-like cells, both during ongoing activity and during application of calibrated noxious pressure to the RF. Microinjection of morphine into RVM induced a correlated decrease in on-like cell/spinal neuron ongoing activity and response to noxious stimulation. RVM morphine induced changes in off-like cell activity that were not correlated with spinal neuronal activity. These results suggest that on-cells exert a positive modulation upon spinal nociceptive neurons, upstream to ventral horn circuits and plausibly at the origin of nociceptive information that eventually reaches the cerebral cortex. On-cells may in this manner contribute to inflammation- and neuropathy-induced increases in withdrawal reflexes. Most significantly, on-cell modulation of nociceptive neurons may be a key factor in clinical pain conditions such as hyperalgesia and allodynia.

  1. Pyridazinopsoralens of wide chemotherapeutic interest.

    PubMed

    Dalla Via, Lisa; Gia, Ornella; Marciani Magno, Sebastiano; Braga, Alessandra; González-Gómez, José Carlos; Pérez-Montoto, Lázaro Guillermo; Uriarte, Eugenio

    2010-08-01

    The synthesis of new 6,10-dimethylpyridazino[4,5-h]psoralens, carrying no (4), one (5), or two (6-9) dialkylaminoalkylcarboxamide side chains on the pyridazine ring is reported. All compounds exert a significant photoantiproliferative activity. Moreover, the derivatives characterised by the protonable side chains show a notable cytotoxicity in the dark. The investigation on the mechanism of action demonstrated the capacity to intercalate into DNA base pairs and to inhibit the relaxation activity of topoisomerase II.

  2. Wide range radioactive gas concentration detector

    DOEpatents

    Anderson, David F.

    1984-01-01

    A wide range radioactive gas concentration detector and monitor which is capable of measuring radioactive gas concentrations over a range of eight orders of magnitude. The device of the present invention is designed to have an ionization chamber which is sufficiently small to give a fast response time for measuring radioactive gases but sufficiently large to provide accurate readings at low concentration levels. Closely spaced parallel plate grids provide a uniform electric field in the active region to improve the accuracy of measurements and reduce ion migration time so as to virtually eliminate errors due to ion recombination. The parallel plate grids are fabricated with a minimal surface area to reduce the effects of contamination resulting from absorption of contaminating materials on the surface of the grids. Additionally, the ionization chamber wall is spaced a sufficient distance from the active region of the ionization chamber to minimize contamination effects.

  3. The adaptive response of jaw muscles to varying functional demands.

    PubMed

    Grünheid, Thorsten; Langenbach, Geerling E J; Korfage, Joannes A M; Zentner, Andrej; van Eijden, Theo M G J

    2009-12-01

    Jaw muscles are versatile entities that are able to adapt their anatomical characteristics, such as size, cross-sectional area, and fibre properties, to altered functional demands. The dynamic nature of muscle fibres allows them to change their phenotype to optimize the required contractile function while minimizing energy use. Changes in these anatomical parameters are associated with changes in neuromuscular activity as the pattern of muscle activation by the central nervous system plays an important role in the modulation of muscle properties. This review summarizes the adaptive response of jaw muscles to various stimuli or perturbations in the orofacial system and addresses general changes in muscles as they adapt, specific adaptive changes in jaw muscles under various physiologic and pathologic conditions, and their adaptive response to non-surgical and surgical therapeutic interventions. Although the jaw muscles are used concertedly in the masticatory system, their adaptive changes are not always uniform and vary with the nature, intensity, and duration of the stimulus. In general, stretch, increases neuromuscular activity, and resistance training result in hypertrophy, elicits increases in mitochondrial content and cross-sectional area of the fibres, and may change the fibre-type composition of the muscle towards a larger percentage of slow-type fibres. In contrast, changes in the opposite direction occur when neuromuscular activity is reduced, the muscle is immobilized in a shortened position, or paralysed. The broad range of stimuli that affect the properties of jaw muscles might help explain the large variability in the anatomical and physiological characteristics found among individuals, muscles, and muscle portions.

  4. Wide Field Instrument Adjutant Scientist

    NASA Astrophysics Data System (ADS)

    Spergel, David

    As Wide Field Instrument Adjutant Scientist, my goal will be to maximize the science capability of the mission in a cost-contained environment. I hope to work with the HQ, project and the FSWG to assure mission success. I plan to play a leadership role in communicating the WFIRST science capabilities to the astronomy community , obtain input from both science teams and the broader community that help derive performance requirements and calibration metrics. I plan to focus on developing the observing program for the deep fields and focus on using them to calibrate instrument performance and capabilities. I plan to organize workshops that will bring together WFIRST team members with astronomers working on LSST, Euclid, JWST, and the ELTs to maximize combined science return. I am also eager to explore the astrometric and stellar seismology capabilities of the instrument with a goal of maximizing science return without affecting science requirements.

  5. The LOFT wide field monitor

    NASA Astrophysics Data System (ADS)

    Brandt, S.; Hernanz, M.; Alvarez, L.; Azzarello, P.; Barret, D.; Bozzo, E.; Budtz-Jørgensen, C.; Campana, R.; del Monte, E.; Donnarumma, I.; Evangalista, Y.; Feroci, M.; Galvez Sanchez, J. L.; Götz, D.; Hansen, F.; den Herder, J. W.; Hudec, R.; Huovelin, J.; Karelin, D.; Korpela, S.; Lund, N.; Orleanski, P.; Pohl, M.; Rashevski, A.; Santangelo, A.; Schanne, S.; Schmid, C.; Suchy, S.; Tenzer, C.; Vacchi, A.; Wilms, J.; Zampa, G.; Zampa, N.; in't Zand, J.; Zdziarski, A.

    2012-09-01

    LOFT (Large Observatory For x-ray Timing) is one of the four missions selected in 2011 for assessment study for the ESA M3 mission in the Cosmic Vision program, expected to be launched in 2024. The LOFT mission will carry two instruments with their prime sensitivity in the 2-30 keV range: a 10 m2 class large area detector (LAD) with a <1° collimated field of view and a wide field monitor (WFM) instrument based on the coded mask principle, providing coverage of more than 1/3 of the sky. The LAD will provide an effective area ~20 times larger than any previous mission and will by timing studies be able to address fundamental questions about strong gravity in the vicinity of black holes and the equation of state of nuclear matter in neutron stars. The prime goal of the WFM will be to detect transient sources to be observed by the LAD. However, with its wide field of view and good energy resolution of <300 eV, the WFM will be an excellent monitoring instrument to study long term variability of many classes of X-ray sources. The sensitivity of the WFM will be 2.1 mCrab in a one day observation, and 270 mCrab in 3s in observations of in the crowded field of the Galactic Center. The high duty cycle of the instrument will make it an ideal detector of fast transient phenomena, like X-ray bursters, soft gamma repeaters, terrestrial gamma flashes, and not least provide unique capabilities in the study of gamma ray bursts. A dedicated burst alert system will enable the distribution to the community of ~100 gamma ray burst positions per year with a ~1 arcmin location accuracy within 30 s of the burst. This paper provides an overview of the design, configuration, and capabilities of the LOFT WFM instrument.

  6. A wide bandwidth CCD buffer memory system

    NASA Technical Reports Server (NTRS)

    Siemens, K.; Wallace, R. W.; Robinson, C. R.

    1978-01-01

    A prototype system was implemented to demonstrate that CCD's can be applied advantageously to the problem of low power digital storage and particularly to the problem of interfacing widely varying data rates. CCD shift register memories (8K bit) were used to construct a feasibility model 128 K-bit buffer memory system. Serial data that can have rates between 150 kHz and 4.0 MHz can be stored in 4K-bit, randomly-accessible memory blocks. Peak power dissipation during a data transfer is less than 7 W, while idle power is approximately 5.4 W. The system features automatic data input synchronization with the recirculating CCD memory block start address. System expansion to accommodate parallel inputs or a greater number of memory blocks can be performed in a modular fashion. Since the control logic does not increase proportionally to increase in memory capacity, the power requirements per bit of storage can be reduced significantly in a larger system.

  7. Genome-wide inhibitory impact of the AMPK activator metformin on [kinesins, tubulins, histones, auroras and polo-like kinases] M-phase cell cycle genes in human breast cancer cells.

    PubMed

    Oliveras-Ferraros, Cristina; Vazquez-Martin, Alejandro; Menendez, Javier A

    2009-05-15

    Prompted by the ever-growing scientific rationale for examining the antidiabetic drug metformin as a potential antitumor agent in breast cancer disease, we recently tested the hypothesis that the assessment of metformin-induced global changes in gene expression-as identified using 44 K (double density) Agilent's whole human genome arrays-could reveal gene-expression signatures that would allow proper selection of breast cancer patients who should be considered for metformin-based clinical trials. Using Database for Annotation, Visualization and Integrated Discovery bioinformatics (DAVID) resources we herein reveal that, at doses that lead to activation of the AMP-activated protein kinase (AMPK), metformin not only downregulates genes coding for ribosomal proteins (i.e., protein and macromolecule biosynthesis) but unexpectedly suppresses numerous mitosis-related gene families including kinesins, tubulins, histones, auroras and polo-like kinases. This is, to our knowledge, the first genome-scale evidence of a mitotic core component in the transcriptional response of human breast cancer cells to metformin. These findings further support a tight relationship between the activation status of AMPK and the chromosomal and cytoskeletal checkpoints of cell mitosis at the transcriptional level.

  8. Holographic cinematography of time-varying reflecting and time-varying phase objects using a Nd:YAG laser

    NASA Technical Reports Server (NTRS)

    Decker, A. J.

    1982-01-01

    The use of a Nd:YAG laser to record holographic motion pictures of time-varying reflecting objects and time-varying phase objects is discussed. Sample frames from both types of holographic motion pictures are presented. The holographic system discussed is intended for three-dimensional flow visualization of the time-varying flows that occur in jet-engine components.

  9. Genome-wide identification of Drosophila Hb9 targets reveals a pivotal role in directing the transcriptome within eight neuronal lineages, including activation of Nitric Oxide Synthase and Fd59a/Fox-D

    PubMed Central

    Lacin, Haluk; Rusch, Jannette; Yeh, Raymond T.; Fujioka, Miki; Wilson, Beth A.; Zhu, Yi; Robie, Alice A.; Mistry, Hemlata; Wang, Ting; Jaynes, James B.; Skeath, James B.

    2014-01-01

    Hb9 is a homeodomain-containing transcription factor that acts in combination with Nkx6, Lim3, and Tail-up (Islet) to guide the stereotyped differentiation, connectivity, and function of a subset of neurons in Drosophila. The role of Hb9 in directing neuronal differentiation is well documented, but the lineage of Hb9+ neurons is only partly characterized, its regulation is poorly understood, and most of the downstream genes through which it acts remain at large. Here, we complete the lineage tracing of all embryonic Hb9+ neurons (to eight neuronal lineages) and provide evidence that hb9, lim3, and tail-up are coordinately regulated by a common set of upstream factors. Through the parallel use of micro-array gene expression profiling and the Dam-ID method, we searched for Hb9-regulated genes, uncovering transcription factors as the most over-represented class of genes regulated by Hb9 (and Nkx6) in the CNS. By a nearly ten-to-one ratio, Hb9 represses rather than activates transcription factors, highlighting transcriptional repression of other transcription factors as a core mechanism by which Hb9 governs neuronal determination. From the small set of genes activated by Hb9, we characterized the expression and function of two – fd59a/foxd, which encodes a transcription factor, and Nitric oxide synthase. Under standard lab conditions, both genes are dispensable for Drosophila development, but Nos appears to inhibit hyper-active behavior and fd59a appears to act in octopaminergic neurons to control egg-laying behavior. Together our data clarify the mechanisms through which Hb9 governs neuronal specification and differentiation and provide an initial characterization of the expression and function of Nos and fd59a in the Drosophila CNS. PMID:24512689

  10. Noise-adaptive nonlinear diffusion filtering of MR images with spatially varying noise levels.

    PubMed

    Samsonov, Alexei A; Johnson, Chris R

    2004-10-01

    Anisotropic diffusion filtering is widely used for MR image enhancement. However, the anisotropic filter is nonoptimal for MR images with spatially varying noise levels, such as images reconstructed from sensitivity-encoded data and intensity inhomogeneity-corrected images. In this work, a new method for filtering MR images with spatially varying noise levels is presented. In the new method, a priori information regarding the image noise level spatial distribution is utilized for the local adjustment of the anisotropic diffusion filter. Our new method was validated and compared with the standard filter on simulated and real MRI data. The noise-adaptive method was demonstrated to outperform the standard anisotropic diffusion filter in both image error reduction and image signal-to-noise ratio (SNR) improvement. The method was also applied to inhomogeneity-corrected and sensitivity encoding (SENSE) images. The new filter was shown to improve segmentation of MR brain images with spatially varying noise levels.

  11. Estimating System-wide Impacts of Smart Grid Demonstrations

    SciTech Connect

    Schneider, Kevin P.; Lightner, Eric M.; Fuller, Jason C.

    2015-03-01

    Quantifying the impact of a new technology on a single specific distribution feeder is relatively easy, but it does not provide insight into the complexities and variations of a system-wide deployment. It is the inability to extrapolate system-wide impacts that hinders the deployment of many promising new technologies. This paper presents a method of extrapolating technology impacts, either simulated or from a field demonstration, from a limited number of distribution feeders to a system-wide impact. The size of the system can vary from the service territory of a single utility, to a region, or to an entire country. The paper will include an example analysis using the United States Department of Energy (DOE) funded Smart Grid Investment Grant (SGIG) projects, extrapolating their benefits to a national level.

  12. Genome-wide identification and expression analysis of the mitogen-activated protein kinase gene family from banana suggest involvement of specific members in different stages of fruit ripening.

    PubMed

    Asif, Mehar Hasan; Lakhwani, Deepika; Pathak, Sumya; Bhambhani, Sweta; Bag, Sumit K; Trivedi, Prabodh Kumar

    2014-03-01

    Mitogen-activated protein kinases (MAPKs) are important components of the tripartite mitogen-activated protein kinase signaling cascade and play an important role in plant growth and development. Although members of the MAPK gene family have been identified in model plants, little information is available regarding this gene family in fruit crops. In this study, we carried out a computational analysis using the Musa Genome database to identify members of the MAPK gene family in banana, an economically important crop and the most popular fruit worldwide. Our analysis identified 25 members of the MAP kinase (MAPK or MPK) gene family. Phylogenetic analyses of MPKs in Arabidopsis, Oryza, and Populus have classified these MPKs into four subgroups. The presence of conserved domains in the deduced amino acid sequences, phylogeny, and genomic organization strongly support their identity as members of the MPK gene family. Expression analysis during ethylene-induced banana fruit ripening suggests the involvement of several MPKs in the ethylene signal transduction pathway that are necessary for banana fruit ripening. Analysis of the cis-regulatory elements in the promoter regions and the involvement of the identified MPKs in various cellular processes, as analyzed using Pathway Studio, suggest a role for the banana MPK gene family in diverse functions related to growth, development, and the stress response. This report is the first concerning the identification of members of a gene family and the elucidation of their role in various processes using the Musa Genome database.

  13. Removal of a wide range of emerging pollutants from wastewater treatment plant discharges by micro-grain activated carbon in fluidized bed as tertiary treatment at large pilot scale.

    PubMed

    Mailler, R; Gasperi, J; Coquet, Y; Buleté, A; Vulliet, E; Deshayes, S; Zedek, S; Mirande-Bret, C; Eudes, V; Bressy, A; Caupos, E; Moilleron, R; Chebbo, G; Rocher, V

    2016-01-15

    Among the solutions to reduce micropollutant discharges into the aquatic environment, activated carbon adsorption is a promising technique and a large scale pilot has been tested at the Seine Centre (240,000 m(3)/d - Paris, France) wastewater treatment plant (WWTP). While most of available works studied fixed bed or contact reactors with a separated separation step, this study assesses a new type of tertiary treatment based on a fluidized bed containing a high mass of activated carbon, continuously renewed. For the first time in the literature, micro-grain activated carbon (μGAC) was studied. The aims were (1) to determine the performances of fluidized bed operating with μCAG on both emerging micropollutants and conventional wastewater quality parameters, and (2) to compare its efficiency and applicability to wastewater to former results obtained with PAC. Thus, conventional wastewater quality parameters (n=11), pharmaceuticals and hormones (PPHs; n=62) and other emerging pollutants (n=57) have been monitored in μGAC configuration during 13 campaigns. A significant correlation has been established between dissolved organic carbon (DOC), PPHs and UV absorbance at 254 nm (UV-254) removals. This confirms that UV-254 could be used as a tertiary treatment performance indicator to monitor the process. This parameter allowed identifying that the removals of UV-254 and DOC reach a plateau from a μGAC retention time (SRT) of 90-100 days. The μGAC configuration substantially improves the overall quality of the WWTP discharges by reducing biological (38-45%) and chemical oxygen demands (21-48%), DOC (13-44%) and UV-254 (22-48%). In addition, total suspended solids (TSS) are retained by the μGAC bed and a biological activity (nitratation) leads to a total elimination of NO2(-). For micropollutants, PPHs have a good affinity for μGAC and high (>60%) or very high (>80%) removals are observed for most of the quantified compounds (n=22/32), i.e. atenolol (92

  14. Wide area continuous offender monitoring

    SciTech Connect

    Hoshen, J.; Drake, G.; Spencer, D.

    1996-11-01

    The corrections system in the U.S. is supervising over five million offenders. This number is rising fast and so are the direct and indirect costs to society. To improve supervision and reduce the cost of parole and probation, first generation home arrest systems were introduced in 1987. While these systems proved to be helpful to the corrections system, their scope is rather limited because they only cover an offender at a single location and provide only a partial time coverage. To correct the limitations of first-generation systems, second-generation wide area continuous electronic offender monitoring systems, designed to monitor the offender at all times and locations, are now on the drawing board. These systems use radio frequency location technology to track the position of offenders. The challenge for this technology is the development of reliable personal locator devices that are small, lightweight, with long operational battery life, and indoors/outdoors accuracy of 100 meters or less. At the center of a second-generation system is a database that specifies the offender`s home, workplace, commute, and time the offender should be found in each. The database could also define areas from which the offender is excluded. To test compliance, the system would compare the observed coordinates of the offender with the stored location for a given time interval. Database logfiles will also enable law enforcement to determine if a monitored offender was present at a crime scene and thus include or exclude the offender as a potential suspect.

  15. The Ooty Wide Field Array

    NASA Astrophysics Data System (ADS)

    Subrahmanya, C. R.; Manoharan, P. K.; Chengalur, Jayaram N.

    2017-03-01

    We describe here an ongoing upgrade to the legacy Ooty Radio Telescope (ORT). The ORT is a cylindrical parabolic cylinder 530 m × 30 m in size operating at a frequency of 326.5 (or z˜3.35 for the HI 21-cm line). The telescope has been constructed on a North-South hill slope whose gradient is equal to the latitude of the hill, making it effectively equatorially mounted. The feed consists of an array of 1056 dipoles. The key feature of this upgrade is the digitization and cross-correlation of the signals of every set of 4-dipoles. This converts the ORT into a 264 element interferometer with a field-of-view of 2∘×27.4∘cos( δ). This upgraded instrument is called the Ooty Wide Field Array (OWFA). This paper briefly describes the salient features of the upgrade, as well as its main science drivers. There are three main science drivers viz. (1) observations of the large scale distribution of HI in the post-reionization era, (2) studies of the propagation of plasma irregularities through the inner heliosphere and (3) blind surveys for transient sources. More details on the upgrade, as well as on the expected science uses can be found in other papers in this special issue.

  16. ROSAT wide field camera mirrors.

    PubMed

    Willingale, R

    1988-04-15

    The ROSAT wide field camera (WFC) is an XUV telescope operating in the 12-250-eV energy band. The mirror system utilizes Wolter-Schwarzschild type I (WS I) grazing incidence optics with a focal length of 525 mm, comprised of three nested aluminum shells with an outermost diameter of 576 mm providing a geometric aperture area of 456 cm(2). The reflecting surfaces are electroless nickel plated and coated with gold to enhance their reflectivity in the XUV. The mirrors have undergone full aperture optical testing, narrow beam XUV testing, and full aperture XUV testing. Measurements of the reflectivity are compared to theoretical values derived from the optical constants of gold in the XUV range. Analysis of the focused distribution is used to estimate the surface roughness and figuring errors of the polished surfaces. The results are compared to the mechanical metrology data collected during manufacture of the shells and the power spectral density of the reflecting surfaces is found to have a power-law form.

  17. ROSAT Wide Field Camera Mirrors

    NASA Astrophysics Data System (ADS)

    Willingale, R.

    1988-08-01

    The ROSAT wide field camera (WFC) is an XUV telescope operating in the 12-250-eV energy band. The mirror system utilizes Wolter-Schwarzschild type I (WSI) grazing incidence optics with a focal length of 525 mm, comprised of three nested aluminum shells with an outermost diameter of 576 mm providing a geometric aperture area of 456 cm2. The reflecting surfaces are electroless nickel plated and coated with gold to enhance their reflectivity in the XUV. The mirrors have undergone full aperture optical testing, narrow beam XUV testing, and full aperture XUV testing. Measurements of the reflectivity are compared to theoretical values derived from the optical constants of gold in the XUV range. Analysis of the focused distribution is used to estimate the surface roughness and figuring errors of the polished surfaces. The results are compared to the mechanical metrology data collected during manufacture of the shells and the power spectral density of the reflecting surfaces is found to have a power-law form.

  18. Activity.

    ERIC Educational Resources Information Center

    Clearing: Nature and Learning in the Pacific Northwest, 1984

    1984-01-01

    Presents three activities: (1) investigating succession in a schoolground; (2) investigating oak galls; and (3) making sun prints (photographs made without camera or darkroom). Each activity includes a list of materials needed and procedures used. (JN)

  19. Propagation of phase modulation signals in time-varying plasma

    NASA Astrophysics Data System (ADS)

    Yang, Min; Li, Xiaoping; Wang, Di; Liu, Yanming; He, Pan

    2016-05-01

    The effects of time-varying plasma to the propagation of phase modulation signals are investigated in this paper. Through theoretical analysis, the mechanism of the interaction between the time-varying plasma and the phase modulation signal is given. A time-varying plasma generator which could produce arbitrary time-varying plasma is built by adjusting the discharge power. A comparison of results from experiment and simulation prove that the time-varying plasma could cause the special rotation of QPSK (Quadrature Phase Shift Keying) constellation, and the mechanism of constellation point's rotation is analyzed. Additionally, the experimental results of the QPSK signals' EVM (Error Vector Magnitude) after time-varying and time-invariant plasma with different ωp/ω are given. This research could be used to improve the TT&C (Tracking Telemeter and Command) system of re-entry vehicles.

  20. Stable Inversion for Nonlinear Nonminimum-Phase Time Varying Systems

    NASA Technical Reports Server (NTRS)

    Devasia, S.; Paden, B.

    1998-01-01

    In this paper, we extend stable inversion to nonlinear time-varying systems and study computational issues; the technique is applicable to minimum-phase as well as nonminimum-phase systems. The inversion technique is new, even in the linear time-varying case, and relies on partitioning (the dichotomic split of) the linearized system dynamics into time-varying, stable, and unstable, submanifolds. This dichotomic split is used to build time-varying filters which are, in turn, the basis of a contraction used to find a bounded inverse input-state trajectory. Finding the inverse input-state trajectory allows the development or exact-output tracking controllers. The method is local to the time-varying trajectory and requires that the internal dynamics vary slowly; however, the method represents a significant advance relative to presently available tracking controllers. Present techniques are restricted to time-invariant nonlinear systems and, in the general case, track only asymptotically.

  1. Wide Range SET Pulse Measurement

    NASA Technical Reports Server (NTRS)

    Shuler, Robert L.; Chen, Li

    2012-01-01

    A method for measuring a wide range of SET pulses is demonstrated. Use of dynamic logic, faster than ordinary CMOS, allows capture of short pulses. A weighted binning of SET lengths allows measurement of a wide range of pulse lengths with compact circuitry. A pulse-length-conservative pulse combiner tree routes SETs from combinational logic to the measurement circuit, allowing SET measurements in circuits that cannot easily be arranged in long chains. The method is applied to add-multiplex combinational logic, and to an array of NFET routing switches, at .35 micron. Pulses are captured in a chain of Domino Logic AND gates. Propagation through the chain is frozen on the trailing edge by dropping low the second "enable" input to the AND gates. Capacitive loading is increased in the latter stages to create an approximately logarithmic weighted binning, so that a broad range of pulse lengths can be captured with a 10 stage capture chain. Simulations show pulses can be captured which are 1/5th the length of those typically captured with leading edge triggered latch methods, and less than the length of those captured with a trailing edge latch method. After capture, the pulse pattern is transferred to an SEU protected shift register for readout. 64 instances of each of two types of logic are used as targets. One is a full adder with a 4 to 1 mux on its inputs. The other is a 4 x 4 NFET routing matrix. The outputs are passed through buffered XNOR comparators to identify pulses, which are merged in a buffered not-nand (OR) tree designed to avoid pulse absorption as much as possible. The output from each of the two test circuits are input into separate pulse measurement circuits. Test inputs were provided so that the circuit could be bench tested and calibrated. A third SET measurement circuit with no inputs was used to judge the contribution from direct hits on the measurement circuit. Heavy ions were used with an LET range from 12 to 176. At LET of 21 and below, the very

  2. Two-mirror, three-reflection telescopes as candidates for sky surveys in ground and space applications. The MINITRUST: an active optics warping telescope for wide-field astronomy

    NASA Astrophysics Data System (ADS)

    Viotti, Roberto F.; La Padula, Cesare D.; Vignato, Agostino; Lemaitre, Gerard R.; Montiel, Pierre; Dohlen, Kjetil

    2002-12-01

    A concept based on a two-mirror, three-reflection telescope has been investigated. Its anastigmatism and flat fielded properties, the compactness and optical performances over 2-2.5 arc deg field of view, make this optical system of high interest for the development of much larger telescopes than with Schmidt designs. The 2MTRT concept is a potential candidate for sky surveys with 2-3 meter class telescopes and particularily well adapted for UV space surveys. Preliminary developments have been carried out with the construction of a 30-cm prototype on Amoretti's design, providing encouraging results. At present, a 45-cm 2MTRT prototype has been realized for ground based sky survey of NEOs, based on active optics (MINITRUST), in order to overcome the difficulty of obtaining three aspherical surfaces. The primary and tertiary lie on the same double vase substrate, and have a rest profile. The hyperbolization is carried out in situ by air depressure. The secondary, in a tulip form substrate, has been hyperbolized by elastic relaxation. The project is planned for operation in 2003.

  3. Genome-Wide Screening of Salt Tolerant Genes by Activation-Tagging Using Dedifferentiated Calli of Arabidopsis and Its Application to Finding Gene for Myo-Inositol-1-P-Synthase

    PubMed Central

    Ahmad, Aftab; Niwa, Yasuo; Goto, Shingo; Kobayashi, Kyoko; Shimizu, Masanori; Ito, Sohei; Usui, Yumiko; Nakayama, Tsutomu; Kobayashi, Hirokazu

    2015-01-01

    Salinity represents a major abiotic stress factor that can adversely limit the production, quality and geographical distribution of crops. In this study we focused on dedifferentiated calli with fundamental cell functions, the salt tolerance of which had not been previously examined. The experimental approach was based on activation tagging without regeneration of plants for the identification of salt-tolerant mutants of Arabidopsis. Among 62,000 transformed calli that were screened, 18 potential mutants resistant to 150 mM NaCl were obtained. Thermal asymmetric interlaced (TAIL)-PCR was performed to determine the location of T-DNA integration in the genome. In one line, referred to as salt tolerant callus 1 (stc1), expression of a gene [At4g39800: myo-inositol-1-P-synthase 1 (MIPS1)] was considerably enhanced in calli. Plants regenerated from calli showed tolerance to salt in germination and subsequent growth. Retransformation of wild-type Arabidopsis with MIPS1 conferred salt tolerance, indicating that MIPS1 is the causal gene. The over-expression of MIPS1 increased the content of total inositol. The involvement of MIPS1 in salt tolerance through the fundamental cell growth has been proved in Arabidopsis. PMID:25978457

  4. Estimating varying coefficients for partial differential equation models.

    PubMed

    Zhang, Xinyu; Cao, Jiguo; Carroll, Raymond J

    2017-01-11

    Partial differential equations (PDEs) are used to model complex dynamical systems in multiple dimensions, and their parameters often have important scientific interpretations. In some applications, PDE parameters are not constant but can change depending on the values of covariates, a feature that we call varying coefficients. We propose a parameter cascading method to estimate varying coefficients in PDE models from noisy data. Our estimates of the varying coefficients are shown to be consistent and asymptotically normally distributed. The performance of our method is evaluated by a simulation study and by an empirical study estimating three varying coefficients in a PDE model arising from LIDAR data.

  5. World-wide aeronautical satellite communications

    NASA Technical Reports Server (NTRS)

    Wood, Peter; Smith, Keith

    1988-01-01

    INMARSAT decided to expand the spectrum covered by its new generation of satellites, INMARSAT-2, to include 1 MHz (subsequently increased to 3 MHz) of the spectrum designed for aeronautical use. It began a design study that led to the specifications for the system that is now being implemented. Subsequently, INMARSAT awarded contracts for the design of avionics and high gain antennas to a number of manufactures, while several of the signatories that provide ground equipment for communicating with the INMARSAT satellites are modifying their earth stations to work with the avionic equipment. As a resullt of these activities, a world-wide aeronautical satellite system supporting both voice and data will become operational in 1989.

  6. Krüppel-like factor 4 is widely expressed in the mouse male and female reproductive tract and responds as an immediate early gene to activation of the protein kinase A in TM4 Sertoli cells.

    PubMed

    Godmann, M; Kosan, C; Behr, R

    2010-04-01

    Krüppel-like factor 4 (KLF4) is a zinc finger transcription factor critically involved in cell proliferation, differentiation, and carcinogenesis. Recently, KLF4 has also been used for the generation of induced pluripotent stem cells. In this study, we analyzed Klf4 expression in different mouse tissues using northern blot analysis and immunohistochemistry. Focusing on the male and female reproductive tract, we showed for the first time that KLF4 is expressed in the epithelia of the murine uterus and the vagina. In the male reproductive tract, we detected KLF4 in the epithelia of the epididymis, ductus deferens, coagulating gland, and the penis. As KLF4 is strongly inducible by FSH signaling in Sertoli cells and as this transcription factor is also involved in Sertoli cell development, we employed the mouse Sertoli cell line TM4 as a model system to investigate i) the induction kinetics of Klf4 upon activation of the cAMP/protein kinase A pathway by forskolin and ii) the effects of Klf4 induction on TM4 cell cycle progression. Interestingly, Klf4 mRNA and protein were rapidly but transiently induced, reaching peak levels after 90-120 min and declining to basal levels within 4 h. Compared with the inducible cAMP early repressor, an immediate early response gene, the induction kinetics of Klf4 is much faster. In conclusion, Klf4 is an immediate early gene in TM4 cells and its expression in several epithelia of the male and female reproductive tract suggests an important role of Klf4 in mouse reproductive functions.

  7. Dictyostelium cells migrate similarly on surfaces of varying chemical composition.

    PubMed

    McCann, Colin P; Rericha, Erin C; Wang, Chenlu; Losert, Wolfgang; Parent, Carole A

    2014-01-01

    During cell migration, cell-substrate binding is required for pseudopod anchoring to move the cell forward, yet the interactions with the substrate must be sufficiently weak to allow parts of the cell to de-adhere in a controlled manner during typical protrusion/retraction cycles. Mammalian cells actively control cell-substrate binding and respond to extracellular conditions with localized integrin-containing focal adhesions mediating mechanotransduction. We asked whether mechanotransduction also occurs during non-integrin mediated migration by examining the motion of the social amoeba Dictyostelium discoideum, which is thought to bind non-specifically to surfaces. We discovered that Dictyostelium cells are able to regulate forces generated by the actomyosin cortex to maintain optimal cell-surface contact area and adhesion on surfaces of various chemical composition and that individual cells migrate with similar speed and contact area on the different surfaces. In contrast, during collective migration, as observed in wound healing and metastasis, the balance between surface forces and protrusive forces is altered. We found that Dictyostelium collective migration dynamics are strongly affected when cells are plated on different surfaces. These results suggest that the presence of cell-cell contacts, which appear as Dictyostelium cells enter development, alter the mechanism cells use to migrate on surfaces of varying composition.

  8. Risk behaviors for varying categories of disability in NELS:88.

    PubMed

    Hollar, David

    2005-11-01

    A large body of research shows that youth with disabilities, who comprise about 13% of the country's school-aged population, report comparable to higher incidence rates of alcohol, tobacco, and other drug (ATOD) use than their peers. Furthermore, youth with disabilities who reported ATOD use or who engaged in binge drinking had significantly more negative educational outcomes and engaged in sexual activity at a younger age than nonusers. This study describes risk factors for substance use, personal characteristics, aspects of the attitudinal environment, and educational, employment, and social outcomes among youth across 6 categories of disability. Data came from the National Center for Education Statistics' National Education Longitudinal Study of 1988-2000 (NELS:88). The findings indicate that (a) youth with varying types of disabilities are relatively homogenous with respect to risk behaviors, personal characteristics, and outcomes; (b) youth with emotional, learning, or multiple disabilities may be at heightened risk for binge drinking and marijuana use; and (c) youth with emotional and multiple disabilities may be less likely to graduate from high school or its equivalent 8 years beyond the 12th grade. Based on these results and limitations of the NELS sampling strategy, appropriate interventions are discussed as well as the need for more definitive operational definitions for disabilities, specifically the biopsychosocial approach used by the International Classification of Functioning, Disability, and Health.

  9. Time-varying boundaries for diffusion models of decision making and response time

    PubMed Central

    Zhang, Shunan; Lee, Michael D.; Vandekerckhove, Joachim; Maris, Gunter; Wagenmakers, Eric-Jan

    2014-01-01

    Diffusion models are widely-used and successful accounts of the time course of two-choice decision making. Most diffusion models assume constant boundaries, which are the threshold levels of evidence that must be sampled from a stimulus to reach a decision. We summarize theoretical results from statistics that relate distributions of decisions and response times to diffusion models with time-varying boundaries. We then develop a computational method for finding time-varying boundaries from empirical data, and apply our new method to two problems. The first problem involves finding the time-varying boundaries that make diffusion models equivalent to the alternative sequential sampling class of accumulator models. The second problem involves finding the time-varying boundaries, at the individual level, that best fit empirical data for perceptual stimuli that provide equal evidence for both decision alternatives. We discuss the theoretical and modeling implications of using time-varying boundaries in diffusion models, as well as the limitations and potential of our approach to their inference. PMID:25538642

  10. Morphodynamic Response of Laboratory Stream Beds to Unsteady Flow Events of Varying Magnitude and Duration

    NASA Astrophysics Data System (ADS)

    Binns, A. D.; Gunsolus, E. H.

    2014-12-01

    Natural processes and anthropogenic activities can cause short-term flow increases in rivers. These changes in flow, such as those caused by extreme rainfall events or seasonal variation in precipitation patterns, can result in substantial, and sometimes quite rapid, adjustments in sediment regime and alluvial stream morphology. Such morphological adjustments can pose short-term erosion hazards, increased risk of flooding, degradation to aquatic habitat, damage to in-stream engineering infrastructure, and re-mobilization of pollutants. Alterations in river hydraulics, sediment transport and stream morphology from specific unsteady events prove challenging to accurately predict and assess. This research quantifies the morphodynamic response of stream beds to unsteady flow events of varying magnitude and duration. For this purpose, a series of experimental runs is conducted in a 0.31 m-wide, 5.0 m-long laboratory sediment transport flume comprised of a well-sorted medium sand. All runs start from flat-bed initial conditions with a given longitudinal slope. The bed is allowed to develop under constant base-flow (antecedent) conditions until equilibrium conditions are reached. For each run a prescribed increase in flow rate for a pre-determined duration is applied to simulate the unsteady flow event. The magnitude of the increase in flow rate and the duration of the event are systematically varied from run to run. In each run measurements of bed morphology are conducted prior to the event (during antecedent flow conditions), at the conclusion of the event, and following a return base-flow (antecedent) conditions. Sediment transport rates are monitored throughout each run. The morphological response and the time-scale of the bed adjustments to unsteady events is quantified. The effect of the magnitude and duration of the flow increase on this increase is evaluated. This study contributes to the development of predictive tools for engineers and hydrologists to better

  11. Genome Wide Methylome Alterations in Lung Cancer.

    PubMed

    Mullapudi, Nandita; Ye, Bin; Suzuki, Masako; Fazzari, Melissa; Han, Weiguo; Shi, Miao K; Marquardt, Gaby; Lin, Juan; Wang, Tao; Keller, Steven; Zhu, Changcheng; Locker, Joseph D; Spivack, Simon D

    2015-01-01

    Aberrant cytosine 5-methylation underlies many deregulated elements of cancer. Among paired non-small cell lung cancers (NSCLC), we sought to profile DNA 5-methyl-cytosine features which may underlie genome-wide deregulation. In one of the more dense interrogations of the methylome, we sampled 1.2 million CpG sites from twenty-four NSCLC tumor (T)-non-tumor (NT) pairs using a methylation-sensitive restriction enzyme- based HELP-microarray assay. We found 225,350 differentially methylated (DM) sites in adenocarcinomas versus adjacent non-tumor tissue that vary in frequency across genomic compartment, particularly notable in gene bodies (GB; p<2.2E-16). Further, when DM was coupled to differential transcriptome (DE) in the same samples, 37,056 differential loci in adenocarcinoma emerged. Approximately 90% of the DM-DE relationships were non-canonical; for example, promoter DM associated with DE in the same direction. Of the canonical changes noted, promoter (PR) DM loci with reciprocal changes in expression in adenocarcinomas included HBEGF, AGER, PTPRM, DPT, CST1, MELK; DM GB loci with concordant changes in expression included FOXM1, FERMT1, SLC7A5, and FAP genes. IPA analyses showed adenocarcinoma-specific promoter DMxDE overlay identified familiar lung cancer nodes [tP53, Akt] as well as less familiar nodes [HBEGF, NQO1, GRK5, VWF, HPGD, CDH5, CTNNAL1, PTPN13, DACH1, SMAD6, LAMA3, AR]. The unique findings from this study include the discovery of numerous candidate The unique findings from this study include the discovery of numerous candidate methylation sites in both PR and GB regions not previously identified in NSCLC, and many non-canonical relationships to gene expression. These DNA methylation features could potentially be developed as risk or diagnostic biomarkers, or as candidate targets for newer methylation locus-targeted preventive or therapeutic agents.

  12. Genome Wide Methylome Alterations in Lung Cancer

    PubMed Central

    Suzuki, Masako; Fazzari, Melissa; Han, Weiguo; Shi, Miao K.; Marquardt, Gaby; Lin, Juan; Wang, Tao; Keller, Steven; Zhu, Changcheng; Locker, Joseph D.; Spivack, Simon D.

    2015-01-01

    Aberrant cytosine 5-methylation underlies many deregulated elements of cancer. Among paired non-small cell lung cancers (NSCLC), we sought to profile DNA 5-methyl-cytosine features which may underlie genome-wide deregulation. In one of the more dense interrogations of the methylome, we sampled 1.2 million CpG sites from twenty-four NSCLC tumor (T)–non-tumor (NT) pairs using a methylation-sensitive restriction enzyme- based HELP-microarray assay. We found 225,350 differentially methylated (DM) sites in adenocarcinomas versus adjacent non-tumor tissue that vary in frequency across genomic compartment, particularly notable in gene bodies (GB; p<2.2E-16). Further, when DM was coupled to differential transcriptome (DE) in the same samples, 37,056 differential loci in adenocarcinoma emerged. Approximately 90% of the DM-DE relationships were non-canonical; for example, promoter DM associated with DE in the same direction. Of the canonical changes noted, promoter (PR) DM loci with reciprocal changes in expression in adenocarcinomas included HBEGF, AGER, PTPRM, DPT, CST1, MELK; DM GB loci with concordant changes in expression included FOXM1, FERMT1, SLC7A5, and FAP genes. IPA analyses showed adenocarcinoma-specific promoter DMxDE overlay identified familiar lung cancer nodes [tP53, Akt] as well as less familiar nodes [HBEGF, NQO1, GRK5, VWF, HPGD, CDH5, CTNNAL1, PTPN13, DACH1, SMAD6, LAMA3, AR]. The unique findings from this study include the discovery of numerous candidate The unique findings from this study include the discovery of numerous candidate methylation sites in both PR and GB regions not previously identified in NSCLC, and many non-canonical relationships to gene expression. These DNA methylation features could potentially be developed as risk or diagnostic biomarkers, or as candidate targets for newer methylation locus-targeted preventive or therapeutic agents. PMID:26683690

  13. How Do Parenting Concepts Vary within and between the Families?

    ERIC Educational Resources Information Center

    Roskam, Isabelle; Meunier, Jean Christophe

    2009-01-01

    How do parenting concepts vary within and between the families? The present study regards parenting as a complex family process by considering three concepts of parenting: styles, differential treatment and coparenting consistency. A main question was addressed: whether and how these parenting concepts vary within the families towards siblings or…

  14. Specimen loading list for the varying temperature experiment

    SciTech Connect

    Qualls, A.L.; Sitterson, R.G.

    1998-09-01

    The varying temperature experiment HFIR-RB-13J has been assembled and inserted in the reactor. Approximately 5300 specimens were cleaned, inspected, matched, and loaded into four specimen holders. A listing of each specimen loaded into the steady temperature holder, its position in the capsule, and the identification of the corresponding specimen loaded into the varying temperature holder is presented in this report.

  15. Extending satisficing control strategy to slowly varying nonlinear systems

    NASA Astrophysics Data System (ADS)

    Binazadeh, T.; Shafiei, M. H.

    2013-04-01

    Based on the satisficing control strategy, a novel approach to design a stabilizing control law for nonlinear time varying systems with slowly varying parameters (slowly varying systems) is presented. The satisficing control strategy has been originally introduced for time-invariant systems; however, this technique does not have any stability proof for time varying systems. In this paper, first, a parametric version of the satisficing control strategy is developed. Then, by considering the time as a frozen parameter, the parametric satisficing control strategy is utilized. Finally, a theorem is presented which suggested a stabilizing satisficing control law for the slowly varying control systems. Moreover, in this theorem, the maximum admissible rate of change of the system dynamics is evaluated. The efficiency of the proposed approach is demonstrated by a computer simulation.

  16. Time varying voltage combustion control and diagnostics sensor

    DOEpatents

    Chorpening, Benjamin T.; Thornton, Jimmy D.; Huckaby, E. David; Fincham, William

    2011-04-19

    A time-varying voltage is applied to an electrode, or a pair of electrodes, of a sensor installed in a fuel nozzle disposed adjacent the combustion zone of a continuous combustion system, such as of the gas turbine engine type. The time-varying voltage induces a time-varying current in the flame which is measured and used to determine flame capacitance using AC electrical circuit analysis. Flame capacitance is used to accurately determine the position of the flame from the sensor and the fuel/air ratio. The fuel and/or air flow rate (s) is/are then adjusted to provide reduced flame instability problems such as flashback, combustion dynamics and lean blowout, as well as reduced emissions. The time-varying voltage may be an alternating voltage and the time-varying current may be an alternating current.

  17. Far and Wide - Microbial Bebop

    SciTech Connect

    Peter Larsen

    2012-10-01

    This musical composition was created from data of microbes (bacteria, algae and other microorganisms) sampled in the English Channel. Argonne National Laboratory biologist Peter Larsen created the songs as a unique way to present and comprehend large datasets. Microbial species of the Order Rickettsiales, such as the highly abundant, free-living planktonic species Pelagibacter ubique, are typical highly abundant taxa in L4 Station data. Its relative abundance in the microbial community at L4 Station follows a distinctive seasonal pattern. In this composition, there are two chords per measure, generated from photosynthetically active radiation measurements and temperature. The melody of each measure is six notes that describe the relative abundance of the Order Rickettsiales. The first note of each measure is from the relative abundance at a time point. The next five notes of a measure follow one of the following patterns: a continuous rise in pitch, a continuous drop in pitch, a rise then drop in pitch, or a drop then rise in pitch. These patterns are matched to the relative abundance of Rickettsiales at the given time point, relative to the previous and subsequent time points. The pattern of notes in a measure is mapped to the relative abundance of Rickettsiales with fewer rests per measure indicating higher abundance. For time points at which Rickettsiales was the most abundant microbial taxa, the corresponding measure is highlighted with a cymbal crash. More information at http://www.anl.gov/articles/songs-key... Image: Diatoms under a microscope: These tiny phytoplankton are encased within a silicate cell wall. Credit: Prof. Gordon T. Taylor, Stony Brook University

  18. The wide field/planetary camera

    NASA Technical Reports Server (NTRS)

    Westphal, J. A.; Baum, W. A.; Code, A. D.; Currie, D. G.; Danielson, G. E.; Gunn, J. E.; Kelsall, T. F.; Kristian, J. A.; Lynds, C. R.; Seidelmann, P. K.

    1982-01-01

    A wide site of potential astronomical and solar system scientific studies using the wide field planetary camera on space telescope are described. The expected performance of the camera as it approaches final assembly and testing is also detailed.

  19. Activities.

    ERIC Educational Resources Information Center

    Bippert, Judy

    1993-01-01

    Presents activities designed to give students an opportunity to solve concrete problems involving spatial relationships and logical thinking utilizing hands-on manipulatives. Provides teacher instructions and four reproducible worksheets. (MDH)

  20. Estimation of Time-Varying Pilot Model Parameters

    NASA Technical Reports Server (NTRS)

    Zaal, Peter M. T.; Sweet, Barbara T.

    2011-01-01

    Human control behavior is rarely completely stationary over time due to fatigue or loss of attention. In addition, there are many control tasks for which human operators need to adapt their control strategy to vehicle dynamics that vary in time. In previous studies on the identification of time-varying pilot control behavior wavelets were used to estimate the time-varying frequency response functions. However, the estimation of time-varying pilot model parameters was not considered. Estimating these parameters can be a valuable tool for the quantification of different aspects of human time-varying manual control. This paper presents two methods for the estimation of time-varying pilot model parameters, a two-step method using wavelets and a windowed maximum likelihood estimation method. The methods are evaluated using simulations of a closed-loop control task with time-varying pilot equalization and vehicle dynamics. Simulations are performed with and without remnant. Both methods give accurate results when no pilot remnant is present. The wavelet transform is very sensitive to measurement noise, resulting in inaccurate parameter estimates when considerable pilot remnant is present. Maximum likelihood estimation is less sensitive to pilot remnant, but cannot detect fast changes in pilot control behavior.

  1. Optical activity of semiconductor nanocrystals with ionic impurities

    NASA Astrophysics Data System (ADS)

    Tepliakov, N. V.; Baimuratov, A. S.; Gun'ko, Yu. K.; Baranov, A. V.; Fedorov, A. V.; Rukhlenko, I. D.

    2017-01-01

    The strength of the enantioselective interaction of chiral semiconductor nanocrystals with circularly polarized light can be varied over a wide range, which finds a series of important applications in modern nanophotonics. As a rule, this interaction is relatively weak, because the dimension of nanocrystals is much smaller than the wavelength of the optical radiation, and the optical activity of nanocrystals is rather low. In this work, we show theoretically that, by applying ion doping, one can significantly enhance the optical activity of nanocrystals and to vary its magnitude over a wide range of values and over a wide range of frequencies. We show that, by precisely arranging impurities inside nanocrystals, one can optimize the rotatory strengths of intraband transitions, making them 100 times stronger than typical rotatory strengths of small chiral molecules.

  2. Widely Tunable Infrared Antennas Using Free Carrier Refraction.

    PubMed

    Lewi, Tomer; Iyer, Prasad P; Butakov, Nikita A; Mikhailovsky, Alexander A; Schuller, Jon A

    2015-12-09

    We demonstrate tuning of infrared Mie resonances by varying the carrier concentration in doped semiconductor antennas. We fabricate spherical silicon and germanium particles of varying sizes and doping concentrations. Single-particle infrared spectra reveal electric and magnetic dipole, quadrupole, and hexapole resonances. We subsequently demonstrate doping-dependent frequency shifts that follow simple Drude models, culminating in the emergence of plasmonic resonances at high doping levels and long wavelengths. These findings demonstrate the potential for actively tuning infrared Mie resonances by optically or electrically modulating charge carrier densities, thus providing an excellent platform for tunable metamaterials.

  3. Measuring the Impact of Varied Instructional Approaches in an Introductory Animal Science Course

    ERIC Educational Resources Information Center

    Bolt, Brian Grady

    2009-01-01

    The objectives of this project were to: evaluate the impact of demographic descriptors (gender, class rank and final grade) on student's self perceived level of engagement in classroom activities; measure the impact of varying teaching styles on a student's likelihood of correctly answering a knowledge based question and: assessing the…

  4. Control design for a class of nonlinear parameter varying systems

    NASA Astrophysics Data System (ADS)

    Cai, Xiushan; Liu, Yang; Zhang, Wei

    2015-07-01

    Stabilisation for a class of one-sided Lipschitz nonlinear parameter varying systems is dealt with in this paper. First, the nonlinear parameter varying system is represented as a subsystem of a differential inclusion. Sufficient conditions for exponential stabilisation for the differential inclusion are given by solving linear matrix inequalities. Then a continuous control law is designed to stabilise the differential inclusion. It leads to stabilising the nonlinear parameter varying system. Finally, a simulation example is presented to show the validity and advantages of the proposed method.

  5. Photic sensitivity for circadian response to light varies with photoperiod.

    PubMed

    Glickman, Gena; Webb, Ian C; Elliott, Jeffrey A; Baltazar, Ricardo M; Reale, Meghan E; Lehman, Michael N; Gorman, Michael R

    2012-08-01

    The response of the circadian system to light varies markedly depending on photic history. Under short day lengths, hamsters exhibit larger maximal light-induced phase shifts as compared with those under longer photoperiods. However, effects of photoperiod length on sensitivity to subsaturating light remain unknown. Here, Syrian hamsters were entrained to long or short photoperiods and subsequently exposed to a 15-min light pulse across a range of irradiances (0-68.03 µW/cm(2)) to phase shift activity rhythms. Phase advances exhibited a dose response, with increasing irradiances eliciting greater phase resetting in both conditions. Photic sensitivity, as measured by the half-saturation constant, was increased 40-fold in the short photoperiod condition. In addition, irradiances that generated similar phase advances under short and long days produced equivalent phase delays, and equal photon doses produced larger delays in the short photoperiod condition. Mechanistically, equivalent light exposure induced greater pERK, PER1, and cFOS immunoreactivity in the suprachiasmatic nuclei of animals under shorter days. Patterns of immunoreactivity in all 3 proteins were related to the size of the phase shift rather than the intensity of the photic stimulus, suggesting that photoperiod modulation of light sensitivity lies upstream of these events within the signal transduction cascade. This modulation of light sensitivity by photoperiod means that considerably less light is necessary to elicit a circadian response under the relatively shorter days of winter, extending upon the known seasonal changes in sensitivity of sensory systems. Further characterizing the mechanisms by which photoperiod alters photic response may provide a potent tool for optimizing light treatment for circadian and affective disorders in humans.

  6. Song trait similarity in great tits varies with social structure.

    PubMed

    Snijders, Lysanne; van der Eijk, Jerine; van Rooij, Erica P; de Goede, Piet; van Oers, Kees; Naguib, Marc

    2015-01-01

    For many animals, long-range signalling is essential to maintain contact with conspecifics. In territorial species, individuals often have to balance signalling towards unfamiliar potential competitors (to solely broadcast territory ownership) with signalling towards familiar immediate neighbours (to also maintain so-called "dear enemy" relations). Hence, to understand how signals evolve due to these multilevel relationships, it is important to understand how general signal traits vary in relation to the overall social environment. For many territorial songbirds dawn is a key signalling period, with several neighbouring individuals singing simultaneously without immediate conflict. In this study we tested whether sharing a territory boundary, rather than spatial proximity, is related to similarity in dawn song traits between territorial great tits (Parus major) in a wild personality-typed population. We collected a large dataset of automatized dawn song recordings from 72 unique male great tits, during the fertile period of their mate, and compared specific song traits between neighbours and non-neighbours. We show here that both song rate and start time of dawn song were repeatable song traits. Moreover, neighbours were significantly more dissimilar in song rate compared to non-neighbours, while there was no effect of proximity on song rate similarity. Additionally, similarity in start time of dawn song was unrelated to sharing a territory boundary, but birds were significantly more similar in start time of dawn song when they were breeding in close proximity of each other. We suggest that the dissimilarity in dawn song rate between neighbours is either the result of neighbouring great tits actively avoiding similar song rates to possibly prevent interference, or a passive consequence of territory settlement preferences relative to the types of neighbours. Neighbourhood structuring is therefore likely to be a relevant selection pressure shaping variation in

  7. High accuracy magnetic field sensors with wide operation temperature range

    NASA Astrophysics Data System (ADS)

    Vasil'evskii, I. S.; Vinichenko, A. N.; Rubakin, D. I.; Bolshakova, I. A.; Kargin, N. I.

    2016-10-01

    n+InAs(Si) epitaxial thin films heavily doped by silicon and Hall effect magnetic field sensors based on this structures have been fabricated and studied. We have demonstrated the successful formation of highly doped InAs thin films (∼100 nm) with the different intermediate layer arrangement and appropriate electron mobility values. Hall sensors performance parameters have been measured in wide temperature range. Obtained sensitivity varied from 1 to 40 Ω/T, while the best linearity and lower temperature coefficient have been found in the higher doped samples with lower electron mobility. We attribute this to the electron system degeneracy and decreased phonon contribution to electron mobility and resistance.

  8. Improved process model for ammonia volatilization from anaerobic swine lagoons under varying wind speeds and gas bubbling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization from treatment lagoons varies widely with the lagoon water total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model using a...

  9. Lifelong Education for the Challenges of a Rich and Varied Future: What Older Americans Look for in Education.

    ERIC Educational Resources Information Center

    Seefer, Richard G.; Heil, Wendy A.

    The educational needs and concerns of midlife and older Americans are as varied as their demographics, family status, economic level, and educational backgrounds. One of the most consistent research findings in adult learning is that the more education people have, the more likely they will be to continue to participate in a wide variety of…

  10. 15 CFR 922.163 - Prohibited activities-Sanctuary-wide.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Florida Keys National Marine Sanctuary... with Federal water resource development projects in existence on July 1, 1997, including maintenance... subsequently enters the Sanctuary and injures a Sanctuary resource or quality, except: (A) Those listed...

  11. 15 CFR 922.163 - Prohibited activities-Sanctuary-wide.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Florida Keys National Marine Sanctuary... with Federal water resource development projects in existence on July 1, 1997, including maintenance... subsequently enters the Sanctuary and injures a Sanctuary resource or quality, except: (A) Those listed...

  12. 15 CFR 922.163 - Prohibited activities-Sanctuary-wide.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Florida Keys National Marine Sanctuary... with Federal water resource development projects in existence on July 1, 1997, including maintenance... subsequently enters the Sanctuary and injures a Sanctuary resource or quality, except: (A) Those listed...

  13. 15 CFR 922.163 - Prohibited activities-Sanctuary-wide.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... RESOURCE MANAGEMENT NATIONAL MARINE SANCTUARY PROGRAM REGULATIONS Florida Keys National Marine Sanctuary... with Federal water resource development projects in existence on July 1, 1997, including maintenance... subsequently enters the Sanctuary and injures a Sanctuary resource or quality, except: (A) Those listed...

  14. 253. Mabry Mill. The varying roof lines and siding gives ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    253. Mabry Mill. The varying roof lines and siding gives the mill an interesting texture, increasing its photogenic value. Looking north. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  15. Spatially Varying Index of Refraction: An Open Ended Undergraduate Topic.

    ERIC Educational Resources Information Center

    Krueger, David A.

    1980-01-01

    Presents an experiment on the bending of light in a medium with a continuously varying index of refraction. Several theoretical approaches for the analysis of this experiment, designed for college physics students, are also presented. (HM)

  16. Buckling Behavior of Long Symmetrically Laminated Plates Subjected to Shear and Linearly Varying Axial Edge Loads

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    1997-01-01

    A parametric study of the buckling behavior of infinitely long symmetrically laminated anisotropic plates that are subjected to linearly varying edge loads, uniform shear loads, or combinations of these loads is presented. The study focuses on the effects of the shape of linearly varying edge load distribution, plate orthotropy, and plate flexural anisotropy on plate buckling behavior. In addition, the study exmines the interaction of linearly varying edge loads and uniform shear loads with plate flexural anisotropy and orthotropy. Results obtained by using a special purpose nondimensional analysis that is well suited for parametric studies of clamped and simply supported plates are presented for [+/- theta](sub s), thin graphite-epoxy laminates that are representative of spacecraft structural components. Also, numerous generic buckling-design charts are presented for a wide range of nondimensional parameters that are applicable to a broad class of laminate constructions. These charts show explicitly the effects of flexural orthotropy and flexural anisotropy on plate buckling behavior for linearly varying edge loads, uniform shear loads, or combinations of these loads. The most important finding of the present study is that specially orthotropic and flexurally anisotropic plates that are subjected to an axial edge load distribution that is tension dominated can support shear loads that are larger in magnitude than the shear buckling load.

  17. Spatially Varying Coefficient Model for Neuroimaging Data with Jump Discontinuities.

    PubMed

    Zhu, Hongtu; Fan, Jianqing; Kong, Linglong

    2014-07-01

    Motivated by recent work on studying massive imaging data in various neuroimaging studies, we propose a novel spatially varying coefficient model (SVCM) to capture the varying association between imaging measures in a three-dimensional (3D) volume (or 2D surface) with a set of covariates. Two stylized features of neuorimaging data are the presence of multiple piecewise smooth regions with unknown edges and jumps and substantial spatial correlations. To specifically account for these two features, SVCM includes a measurement model with multiple varying coefficient functions, a jumping surface model for each varying coefficient function, and a functional principal component model. We develop a three-stage estimation procedure to simultaneously estimate the varying coefficient functions and the spatial correlations. The estimation procedure includes a fast multiscale adaptive estimation and testing procedure to independently estimate each varying coefficient function, while preserving its edges among different piecewise-smooth regions. We systematically investigate the asymptotic properties (e.g., consistency and asymptotic normality) of the multiscale adaptive parameter estimates. We also establish the uniform convergence rate of the estimated spatial covariance function and its associated eigenvalues and eigenfunctions. Our Monte Carlo simulation and real data analysis have confirmed the excellent performance of SVCM.

  18. Activities.

    ERIC Educational Resources Information Center

    Kincaid, Charlene; And Others

    1993-01-01

    Presents an activity in which students collect and organize data from a real-world simulation of the scientific concept of half life. Students collect data using a marble sifter, analyze the data using a graphing calculator, and determine an appropriate mathematical model. Includes reproducible worksheets. (MDH)

  19. Control of Magnetic Bearings for Rotor Unbalance With Plug-In Time-Varying Resonators

    PubMed Central

    Kang, Christopher; Tsao, Tsu-Chin

    2016-01-01

    Rotor unbalance, common phenomenon of rotational systems, manifests itself as a periodic disturbance synchronized with the rotor's angular velocity. In active magnetic bearing (AMB) systems, feedback control is required to stabilize the open-loop unstable electromagnetic levitation. Further, feedback action can be added to suppress the repeatable runout but maintain closed-loop stability. In this paper, a plug-in time-varying resonator is designed by inverting cascaded notch filters. This formulation allows flexibility in designing the internal model for appropriate disturbance rejection. The plug-in structure ensures that stability can be maintained for varying rotor speeds. Experimental results of an AMB–rotor system are presented. PMID:27222600

  20. Control of Magnetic Bearings for Rotor Unbalance With Plug-In Time-Varying Resonators.

    PubMed

    Kang, Christopher; Tsao, Tsu-Chin

    2016-01-01

    Rotor unbalance, common phenomenon of rotational systems, manifests itself as a periodic disturbance synchronized with the rotor's angular velocity. In active magnetic bearing (AMB) systems, feedback control is required to stabilize the open-loop unstable electromagnetic levitation. Further, feedback action can be added to suppress the repeatable runout but maintain closed-loop stability. In this paper, a plug-in time-varying resonator is designed by inverting cascaded notch filters. This formulation allows flexibility in designing the internal model for appropriate disturbance rejection. The plug-in structure ensures that stability can be maintained for varying rotor speeds. Experimental results of an AMB-rotor system are presented.