Grid-Level Application of Electrical Energy Storage: Example Use Cases in the United States and China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yingchen; Gevorgian, Vahan; Wang, Caixia

Electrical energy storage (EES) systems are expected to play an increasing role in helping the United States and China-the world's largest economies with the two largest power systems-meet the challenges of integrating more variable renewable resources and enhancing the reliability of power systems by improving the operating capabilities of the electric grid. EES systems are becoming integral components of a resilient and efficient grid through a diverse set of applications that include energy management, load shifting, frequency regulation, grid stabilization, and voltage support.

Properties of K,Rb-intercalated C{sub 60} encapsulated inside carbon nanotubes called peapods derived from nuclear magnetic resonance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahfouz, R.; Bouhrara, M.; Kim, Y.

2015-09-21

We present a detailed experimental study on how magnetic and electronic properties of Rb,K-intercalated C{sub 60} encapsulated inside carbon nanotubes called peapods can be derived from {sup 13}C nuclear magnetic resonance investigations. Ring currents do play a basic role in those systems; in particular, the inner cavities of nanotubes offer an ideal environment to investigate the magnetism at the nanoscale. We report the largest diamagnetic shifts down to −68.3 ppm ever observed in carbon allotropes, which is connected to the enhancement of the aromaticity of the nanotube envelope upon intercalation. The metallization of intercalated peapods is evidenced from the chemical shiftmore » anisotropy and spin-lattice relaxation (T{sub 1}) measurements. The observed relaxation curves signal a three-component model with two slow and one fast relaxing components. We assigned the fast component to the unpaired electrons charged C{sub 60} that show a phase transition near 100 K. The two slow components can be rationalized by the two types of charged C{sub 60} at two different positions with a linear regime following Korringa behavior, which is typical for metallic system and allow us to estimate the density of sate at Fermi level n(E{sub F})« less

Comparative Study Between Wind and Photovoltaic (PV) Systems

NASA Astrophysics Data System (ADS)

Taha, Wesam

This paper reviews two renewable energy systems; wind and photovoltaic (PV) systems. The common debate between the two of them is to conclude which one is better, in terms of cost and efficiency. Therefore, comparative study, in terms of cost and efficiency, is attempted. Regarding total cost of both, wind and PV systems, many parameters must be taken into consideration such as availability of energy (either wind or solar), operation and maintenance, availability of costumers, political influence, and the components used in building the system. The main components and parameters that play major role in determining the overall efficiency of wind systems are the wind turbine generator (WTG), gearbox and control technologies such as power, and speed control. On the other hand, in grid-connected PV systems (GCPVS), converter architecture along with maximum power point tracking (MPPT) algorithm and inverter topologies are the issues that affects the efficiency significantly. Cost and efficiency analyses of both systems have been carried out based on the statistics available till today and would be useful in the progress of renewable energy penetration throughout the world.

Two Variations of Video Modeling Interventions for Teaching Play Skills to Children with Autism

ERIC Educational Resources Information Center

Sancho, Kimberly; Sidener, Tina M.; Reeve, Sharon A.; Sidener, David W.

2010-01-01

The current study employed an adapted alternating treatments design with reversal and multiple probe across participants components to compare the effects of traditional video priming and simultaneous video modeling on the acquisition of play skills in two children diagnosed with autism. Generalization was programmed across play sets, instructors,…

A Unique Fungal Two-Component System Regulates Stress Responses, Drug Sensitivity, Sexual Development, and Virulence of Cryptococcus neoformans

PubMed Central

Bahn, Yong-Sun; Kojima, Kaihei; Cox, Gary M.

2006-01-01

The stress-activated mitogen-activated protein kinase (MAPK) pathway is widely used by eukaryotic organisms as a central conduit via which cellular responses to the environment effect growth and differentiation. The basidiomycetous human fungal pathogen Cryptococcus neoformans uniquely uses the stress-activated Pbs2-Hog1 MAPK system to govern a plethora of cellular events, including stress responses, drug sensitivity, sexual reproduction, and virulence. Here, we characterized a fungal “two-component” system that controls these fundamental cellular functions via the Pbs2-Hog1 MAPK cascade. A typical response regulator, Ssk1, modulated all Hog1-dependent phenotypes by controlling Hog1 phosphorylation, indicating that Ssk1 is the major upstream signaling component of the Pbs2-Hog1 pathway. A second response regulator, Skn7, governs sensitivity to Na+ ions and the antifungal agent fludioxonil, negatively controls melanin production, and functions independently of Hog1 regulation. To control these response regulators, C. neoformans uses multiple sensor kinases, including two-component–like (Tco) 1 and Tco2. Tco1 and Tco2 play shared and distinct roles in stress responses and drug sensitivity through the Hog1 MAPK system. Furthermore, each sensor kinase mediates unique cellular functions for virulence and morphological differentiation. Our findings highlight unique adaptations of this global two-component MAPK signaling cascade in a ubiquitous human fungal pathogen. PMID:16672377

Universal Plug-n-Play Sensor Integration for Advanced Navigation

DTIC Science & Technology

2012-03-22

Orientation (top) and Angular Velocity (bottom) . . . . . . . . . 79 IV.6 Execution of AHRS script with roscore running on separate machine . . . . . . 80...single host case only with two hosts in this scenario. The script is running 78 Figure IV.5: Plot of AHRS Orientation (top) and Angular Velocity (bottom...Component-Based System using ROS . . . . . . . . . 59 3.6 Autonomous Behavior Using Scripting . . . . . . . . . . . . . . . . . . . . 60 3.6.1 udev

Regulation of virulence by a two-component system in group B streptococcus.

PubMed

Jiang, Sheng-Mei; Cieslewicz, Michael J; Kasper, Dennis L; Wessels, Michael R

2005-02-01

Group B Streptococcus (GBS) is frequently carried in the gastrointestinal or genitourinary tract as a commensal organism, yet it has the potential to cause life-threatening infection in newborn infants, pregnant women, and individuals with chronic illness. Regulation of virulence factor expression may affect whether GBS behaves as an asymptomatic colonizer or an invasive pathogen, but little is known about how such factors are controlled in GBS. We now report the characterization of a GBS locus that encodes a two-component regulatory system similar to CsrRS (or CovRS) in Streptococcus pyogenes. Inactivation of csrR, encoding the putative response regulator, in two unrelated wild-type strains of GBS resulted in a marked increase in production of beta-hemolysin/cytolysin and a striking decrease in production of CAMP factor, an unrelated cytolytic toxin. Quantitative RNA hybridization experiments revealed that these two phenotypes were associated with a marked increase and decrease in expression of the corresponding genes, cylE and cfb, respectively. The CsrR mutant strains also displayed increased expression of scpB encoding C5a peptidase. Similar, but less marked, changes in gene expression were observed in CsrS (putative sensor component) mutants, evidence that CsrR and CsrS constitute a functional two-component system. Experimental infection studies in mice demonstrated reduced virulence of both CsrR and CsrS mutant strains relative to the wild type. Together, these results indicate that CsrRS regulates expression of multiple GBS virulence determinants and is likely to play an important role in GBS pathogenesis.

A two-component signal transduction pathway regulates manganese homeostasis in Synechocystis 6803, a photosynthetic organism.

PubMed

Ogawa, Teruo; Bao, Ding Hui; Katoh, Hirokazu; Shibata, Mari; Pakrasi, Himadri B; Bhattacharyya-Pakrasi, Maitrayee

2002-08-09

Elemental manganese is essential for the production of molecular oxygen by cyanobacteria, plants, and algae. In the cyanobacterium Synechocystis sp. PCC 6803, transcription of the mntCAB operon, encoding a high affinity Mn transporter, occurs under Mn starvation (nm Mn) conditions but not in Mn-sufficient (microm Mn) growth medium. Using a strain in which the promoter of this operon directs the transcription of the luxAB reporter genes, we determined that inactivation of the slr0640 gene, which encodes a histidine kinase sensor protein component of a two-component signal transduction system, resulted in constitutive high levels of lux luminescence. Systematic targeted inactivation mutagenesis also identified slr1837 as the gene encoding the corresponding response regulator protein. We have named these two genes manS (manganese-sensor) and manR (manganese-regulator), respectively. A polyhistidine-tagged form of the ManS protein was localized in the Synechocystis 6803 cell membrane. Directed replacement of the conserved catalytic His-205 residue of this protein by Leu abolished its activity, although the mutated protein was present in cyanobacterial membrane. This mutant also showed suboptimal rates of Mn uptake under either Mn-starved or Mn-sufficient growth condition. These data suggest that the ManS/ManR two-component system plays a central role in the homeostasis of manganese in Synechocystis 6803 cells.

The Role of Transition Metal Transporters for Iron, Zinc, Manganese, and Copper in the Pathogenesis of Yersinia pestis

PubMed Central

Perry, Robert D.; Bobrov, Alexander G.; Fetherston, Jacqueline D.

2015-01-01

Yersinia pestis, the causative agent of bubonic, septicemic and pneumonic plague, encodes a multitude of Fe transport systems. Some of these are defective due to frameshift or IS element insertions, while others are functional in vitro but have no established role in causing infections. Indeed only 3 Fe transporters (Ybt, Yfe and Feo) have been shown to be important in at least one form of plague. The yersiniabactin (Ybt) system is essential in the early dermal/lymphatic stages of bubonic plague, irrelevant in the septicemic stage, and critical in pneumonic plague. Two Mn transporters have been characterized (Yfe and MntH). These two systems play a role in bubonic plague but the double yfe mntH mutant is fully virulent in a mouse model of pneumonic plague. The same in vivo phenotype occurs with a mutant lacking two (Yfe and Feo) of four ferrous transporters. A role for the Ybt siderophore in Zn acquisition has been revealed. Ybt-dependent Zn acquisition uses a transport system completely independent of the Fe-Ybt uptake system. Together Ybt components and ZnuABC play a critical role in Zn acquisition in vivo. Single mutants in either system retain high virulence in a mouse model of septicemic plague while the double mutant is completely avirulent. PMID:25891079

The role of transition metal transporters for iron, zinc, manganese, and copper in the pathogenesis of Yersinia pestis.

PubMed

Perry, Robert D; Bobrov, Alexander G; Fetherston, Jacqueline D

2015-06-01

Yersinia pestis, the causative agent of bubonic, septicemic and pneumonic plague, encodes a multitude of Fe transport systems. Some of these are defective due to frameshift or IS element insertions, while others are functional in vitro but have no established role in causing infections. Indeed only 3 Fe transporters (Ybt, Yfe and Feo) have been shown to be important in at least one form of plague. The yersiniabactin (Ybt) system is essential in the early dermal/lymphatic stages of bubonic plague, irrelevant in the septicemic stage, and critical in pneumonic plague. Two Mn transporters have been characterized (Yfe and MntH). These two systems play a role in bubonic plague but the double yfe mntH mutant is fully virulent in a mouse model of pneumonic plague. The same in vivo phenotype occurs with a mutant lacking two (Yfe and Feo) of four ferrous transporters. A role for the Ybt siderophore in Zn acquisition has been revealed. Ybt-dependent Zn acquisition uses a transport system completely independent of the Fe-Ybt uptake system. Together Ybt components and ZnuABC play a critical role in Zn acquisition in vivo. Single mutants in either system retain high virulence in a mouse model of septicemic plague while the double mutant is completely avirulent.

Living supramolecular polymerization achieved by collaborative assembly of platinum(II) complexes and block copolymers

PubMed Central

Zhang, Kaka; Yeung, Margaret Ching-Lam; Leung, Sammual Yu-Lut; Yam, Vivian Wing-Wah

2017-01-01

An important feature of biological systems to achieve complexity and precision is the involvement of multiple components where each component plays its own role and collaborates with other components. Mimicking this, we report living supramolecular polymerization achieved by collaborative assembly of two structurally dissimilar components, that is, platinum(II) complexes and poly(ethylene glycol)-b-poly(acrylic acid) (PEG-b-PAA). The PAA blocks neutralize the charges of the platinum(II) complexes, with the noncovalent metal–metal and π–π interactions directing the longitudinal growth of the platinum(II) complexes into 1D crystalline nanostructures, and the PEG blocks inhibiting the transverse growth of the platinum(II) complexes and providing the whole system with excellent solubility. The ends of the 1D crystalline nanostructures have been found to be active during the assembly and remain active after the assembly. One-dimensional segmented nanostructures with heterojunctions have been produced by sequential growth of two types of platinum(II) complexes. The PAA blocks act as adapters at the heterojunctions for lattice matching between chemically and crystallographically different platinum(II) complexes, achieving heterojunctions with a lattice mismatch as large as 21%. PMID:29078381

Spin correlations in the {Lambda}{Lambda} and {Lambda}{Lambda}-bar systems generated in relativistic heavy-ion collisions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyuboshitz, V. L.; Lyuboshitz, V. V., E-mail: Valery.Lyuboshitz@jinr.r

2010-05-15

Spin correlations for the {Lambda}{Lambda} and {Lambda}{Lambda}-bar pairs, generated in relativistic heavy-ion collisions, and related angular correlations at the joint registration of hadronic decays of two hyperons, in which space parity is not conserved, are analyzed. The correlation tensor components can be derived from the double angular distribution of products of two decays by the method of 'moments'. The properties of the 'trace' of the correlation tensor (a sum of three diagonal components), determining the relative fractions of the triplet states and singlet state of respective pairs, are discussed. Spin correlations for two identical particles ({Lambda}{Lambda}) and two nonidentical particlesmore » ({Lambda}{Lambda}-bar) are considered from the viewpoint of the conventional model of one-particle sources. In the framework of this model, correlations vanish at sufficiently large relative momenta. However, under these conditions, in the case of two nonidentical particles ({Lambda}{Lambda}-bar) a noticeable role is played by two-particle annihilation (two-quark, two-gluon) sources, which lead to the difference of the correlation tensor from zero. In particular, such a situation may arise when the system passes through the 'mixed phase.'« less

The coevolution of play and the cortico-cerebellar system in primates.

PubMed

Kerney, Max; Smaers, Jeroen B; Schoenemann, P Thomas; Dunn, Jacob C

2017-10-01

Primates are some of the most playful animals in the natural world, yet the reason for this remains unclear. One hypothesis posits that primates are so playful because playful activity functions to help develop the sophisticated cognitive and behavioural abilities that they are also renowned for. If this hypothesis were true, then play might be expected to have coevolved with the neural substrates underlying these abilities in primates. Here, we tested this prediction by conducting phylogenetic comparative analyses to determine whether play has coevolved with the cortico-cerebellar system, a neural system known to be involved in complex cognition and the production of complex behaviour. We used phylogenetic generalised least squares analyses to compare the relative volume of the largest constituent parts of the primate cortico-cerebellar system (prefrontal cortex, non-prefrontal heteromodal cortical association areas, and posterior cerebellar hemispheres) to the mean percentage of time budget spent in play by a sample of primate species. Using a second categorical data set on play, we also used phylogenetic analysis of covariance to test for significant differences in the volume of the components of the cortico-cerebellar system among primate species exhibiting one of three different levels of adult-adult social play. Our results suggest that, in general, a positive association exists between the amount of play exhibited and the relative size of the main components of the cortico-cerebellar system in our sample of primate species. Although the explanatory power of this study is limited by the correlational nature of its analyses and by the quantity and quality of the data currently available, this finding nevertheless lends support to the hypothesis that play functions to aid the development of cognitive and behavioural abilities in primates.

3- to 13-micron spectra of Io

NASA Technical Reports Server (NTRS)

Noll, Keith S.; Hammel, H. B.; Young, Leslie; Joiner, Joanna; Hackwell, J.; Lynch, D. K.; Russell, R.

1993-01-01

The Broadband Array Spectrograph System with the NASA Infrared Telescope Facility was used to obtain 3- to 13-micron spectra of Io on June 14-16, 1991. The extinction correction and its error for each standard star (Alpha Boo, Alpha Lyr, and Mu UMa) were found individually by performing an unweighted linear fit of instrumental magnitude as a function of airmass. The model results indicate two significant trends: (1) modest differences between the two hemispheres at lower background temperatures and (2) a tendency to higher temperatures, smaller areas, and less power from the warm component at higher background temperatures with an increased contrast between the two hemispheres. The increased flux from 8 to 13 microns is due primarily to a greater area on the Loki (trailing) hemisphere for the warm component, although temperature also plays a role.

Coherence resonance and stochastic resonance in directionally coupled rings

NASA Astrophysics Data System (ADS)

Werner, Johannes Peter; Benner, Hartmut; Florio, Brendan James; Stemler, Thomas

2011-11-01

In coupled systems, symmetry plays an important role for the collective dynamics. We investigate the dynamical response to noise with and without weak periodic modulation for two classes of ring systems. Each ring system consists of unidirectionally coupled bistable elements but in one class, the number of elements is even while in the other class the number is odd. Consequently, the rings without forcing show at a certain coupling strength, either ordering (similar to anti-ferromagnetic chains) or auto-oscillations. Analysing the bifurcations and fixed points of the two ring classes enables us to explain the dynamical response measured to noise and weak modulation. Moreover, by analysing a simplified model, we demonstrate that the response is universal for systems having a directional component in their stochastic dynamics in phase space around the origin.

Is drop impact the same for both moving and inclined surfaces?

NASA Astrophysics Data System (ADS)

Buksh, Salman; Marengo, Marco; Amirfazli, Alidad; -Team

2017-11-01

Drop impact is an important phenomenon in a wide variety of applications. Researchers have largely examined drop impact onto a moving surface, and an inclined surface separately. Given that in both systems the impact phenomenon is influenced by tangential and normal velocity components, the question remains, if these two systems are essentially equivalent or gravity and boundary layer effects are such that the outcomes will be different. Experiments have been performed by varying liquid surface tension, viscosity and both normal and tangential velocities (0.3 to 2.9 m/s). The desired velocity components were achieved by changing the height where drop is released, the surface inclination angle for inclined system, and the horizontal velocity for the moving surface. To compare the systems, spreading was analyzed by measuring the width and length of the lamella at various time intervals; for splashing, top view images were compared to see the extent of splashing at initial stage. The data suggests that, for the given velocity, neither the boundary layer differences between the two systems nor the gravity play a role on spreading and splashing of the drop, as such one system can replace the other for future studies.

Manned Mars mission crew factors

NASA Technical Reports Server (NTRS)

Santy, Patricia A.

1986-01-01

Crew factors include a wide range of concerns relating to the human system and its role in a Mars mission. There are two important areas which will play a large part in determining the crew for a Mars mission. The first relates to the goals and priorities determined for such a vast endeavor. The second is the design of the vehicle for the journey. The human system cannot be separated from the other systems in that vehicle. In fact it will be the human system which drives the development of many of the technical breakthroughs necessary to make a Mars mission successful. As much as possible, the engineering systems must adapt to the needs of the human system and its individual components.

A Play and Language Intervention for Two-Year-Old Children: Implications for Improving Play Skills and Language

ERIC Educational Resources Information Center

Conner, Julie; Kelly-Vance, Lisa; Ryalls, Brigette; Friehe, Mary

2014-01-01

The purpose of this study was to develop an intervention for 2-year-old children to enhance play and language skills. The intervention was implemented over a 4-week period and included components of reading, modeling, and positive reinforcement of language and play. Specifically, children were read a story and played with a matching toy set.…

Sensor fusion of phase measuring profilometry and stereo vision for three-dimensional inspection of electronic components assembled on printed circuit boards.

PubMed

Hong, Deokhwa; Lee, Hyunki; Kim, Min Young; Cho, Hyungsuck; Moon, Jeon Il

2009-07-20

Automatic optical inspection (AOI) for printed circuit board (PCB) assembly plays a very important role in modern electronics manufacturing industries. Well-developed inspection machines in each assembly process are required to ensure the manufacturing quality of the electronics products. However, generally almost all AOI machines are based on 2D image-analysis technology. In this paper, a 3D-measurement-method-based AOI system is proposed consisting of a phase shifting profilometer and a stereo vision system for assembled electronic components on a PCB after component mounting and the reflow process. In this system information from two visual systems is fused to extend the shape measurement range limited by 2pi phase ambiguity of the phase shifting profilometer, and finally to maintain fine measurement resolution and high accuracy of the phase shifting profilometer with the measurement range extended by the stereo vision. The main purpose is to overcome the low inspection reliability problem of 2D-based inspection machines by using 3D information of components. The 3D shape measurement results on PCB-mounted electronic components are shown and compared with results from contact and noncontact 3D measuring machines. Based on a series of experiments, the usefulness of the proposed sensor system and its fusion technique are discussed and analyzed in detail.

Defense strategies for cloud computing multi-site server infrastructures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, Nageswara S.; Ma, Chris Y. T.; He, Fei

We consider cloud computing server infrastructures for big data applications, which consist of multiple server sites connected over a wide-area network. The sites house a number of servers, network elements and local-area connections, and the wide-area network plays a critical, asymmetric role of providing vital connectivity between them. We model this infrastructure as a system of systems, wherein the sites and wide-area network are represented by their cyber and physical components. These components can be disabled by cyber and physical attacks, and also can be protected against them using component reinforcements. The effects of attacks propagate within the systems, andmore » also beyond them via the wide-area network.We characterize these effects using correlations at two levels using: (a) aggregate failure correlation function that specifies the infrastructure failure probability given the failure of an individual site or network, and (b) first-order differential conditions on system survival probabilities that characterize the component-level correlations within individual systems. We formulate a game between an attacker and a provider using utility functions composed of survival probability and cost terms. At Nash Equilibrium, we derive expressions for the expected capacity of the infrastructure given by the number of operational servers connected to the network for sum-form, product-form and composite utility functions.« less

Dynamic trapping of a polarization rotation vector soliton in a fiber laser.

PubMed

Liu, Meng; Luo, Ai-Ping; Luo, Zhi-Chao; Xu, Wen-Cheng

2017-01-15

Ultrafast fiber laser, as a dissipative nonlinear optical system, plays an important role in investigating various nonlinear phenomena and soliton dynamics. Vector features of solitons, including polarization locked and polarization rotation vector solitons (PRVSs), are interesting nonlinear dynamics in ultrafast fiber lasers. Herein, we experimentally reveal the trapping characteristics of PRVSs for the first time, to the best of our best knowledge. We show that, for the conventional soliton trapping in the ultrafast fiber laser, the soliton central wavelengths of the two polarization components are constant at the laser output port. However, it is found that the dynamic trapping can be observed for the PRVS. That is, the peak frequencies along the two orthogonal polarization directions are dynamically alternating, depending on the relative intensities of the two polarization components. The obtained results would further unveil the physical mechanism of PRVSs.

A hybrid two-component system protein from Azospirillum brasilense Sp7 was involved in chemotaxis.

PubMed

Cui, Yanhua; Tu, Ran; Wu, Lixian; Hong, Yuanyuan; Chen, Sanfeng

2011-09-20

We here report the sequence and functional analysis of org35 of Azospirillum brasilense Sp7, which was originally identified to be able to interact with NifA in yeast-two-hybrid system. The org35 encodes a hybrid two-component system protein, including N-terminal PAS domains, a histidine kinase (HPK) domain and a response regulator (RR) domain in C-terminal. To determine the function of the Org35, a deletion-insertion mutant in PAS domain [named Sp7353] and a complemental strain Sp7353C were constructed. The mutant had reduced chemotaxis ability compared to that of wild-type, and the complemental strain was similar to the wild-type strain. These data suggested that the A. brasilense org35 played a key role in chemotaxis. Variants containing different domains of the org35 were expressed, and the functions of these domains were studied in vitro. Phosphorylation assays in vitro demonstrated that the HPK domain of Org35 possessed the autokinase activity and that the phosphorylated HPK was able to transfer phosphate groups to the RR domain. The result indicated Org35 was a phosphorylation-communicating protein. Copyright © 2010 Elsevier GmbH. All rights reserved.

A study on the dynamics of the zraP gene expression profile and its application to the construction of zinc adsorption bacteria.

PubMed

Ravikumar, Sambandam; Yoo, Ik-keun; Lee, Sang Yup; Hong, Soon Ho

2011-11-01

Zinc ion plays essential roles in biological chemistry. Bacteria acquire Zn(2+) from the environment, and cellular concentration levels are controlled by zinc homeostasis systems. In comparison with other homeostatic systems, the ZraSR two-component system was found to be more efficient in responding to exogenous zinc concentrations. To understand the dynamic response of the bacterium ZraSR two-component system with respect to exogenous zinc concentrations, the genetic circuit of the ZraSR system was integrated with a reporter protein. This study was helpful in the construction of an E. coli system that can display selective metal binding peptides on the surface of the cell in response to exogenous zinc. The engineered bacterial system for monitoring exogenous zinc was successfully employed to detect levels of zinc as low as 0.001 mM, which directly activates the expression of chimeric ompC(t)--zinc binding peptide gene to remove zinc by adsorbing a maximum of 163.6 μmol of zinc per gram of dry cell weight. These results indicate that the engineered bacterial strain developed in the present study can sense the specific heavy metal and activates a cell surface display system that acts to remove the metal.

The CasKR Two-Component System Is Required for the Growth of Mesophilic and Psychrotolerant Bacillus cereus Strains at Low Temperatures

PubMed Central

Diomandé, Sara Esther; Chamot, Stéphanie; Antolinos, Vera; Vasai, Florian; Guinebretière, Marie-Hélène; Bornard, Isabelle; Nguyen-the, Christophe; Broussolle, Véronique

2014-01-01

The different strains of Bacillus cereus can grow at temperatures covering a very diverse range. Some B. cereus strains can grow in chilled food and consequently cause food poisoning. We have identified a new sensor/regulator mechanism involved in low-temperature B. cereus growth. Construction of a mutant of this two-component system enabled us to show that this system, called CasKR, is required for growth at the minimal temperature (Tmin). CasKR was also involved in optimal cold growth above Tmin and in cell survival below Tmin. Microscopic observation showed that CasKR plays a key role in cell shape during cold growth. Introducing the casKR genes in a ΔcasKR mutant restored its ability to grow at Tmin. Although it was first identified in the ATCC 14579 model strain, this mechanism has been conserved in most strains of the B. cereus group. We show that the role of CasKR in cold growth is similar in other B. cereus sensu lato strains with different growth temperature ranges, including psychrotolerant strains. PMID:24509924

A Proposed Information Architecture for Telehealth System Interoperability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craft, R.L.; Funkhouser, D.R.; Gallagher, L.K.

1999-04-20

We propose an object-oriented information architecture for telemedicine systems that promotes secure `plug-and-play' interaction between system components through standardized interfaces, communication protocols, messaging formats, and data definitions. In this architecture, each component functions as a black box, and components plug together in a ''lego-like'' fashion to achieve the desired device or system functionality. Introduction Telemedicine systems today rely increasingly on distributed, collaborative information technology during the care delivery process. While these leading-edge systems are bellwethers for highly advanced telemedicine, most are custom-designed and do not interoperate with other commercial offerings. Users are limited to a set of functionality that amore » single vendor provides and must often pay high prices to obtain this functionality, since vendors in this marketplace must deliver en- tire systems in order to compete. Besides increasing corporate research and development costs, this inhibits the ability of the user to make intelligent purchasing decisions regarding best-of-breed technologies. This paper proposes a reference architecture for plug-and-play telemedicine systems that addresses these issues.« less

The Evolution of Two-Component Systems in Bacteria Reveals Different Strategies for Niche Adaptation

PubMed Central

Arkin, Adam

2006-01-01

Two-component systems including histidine protein kinases represent the primary signal transduction paradigm in prokaryotic organisms. To understand how these systems adapt to allow organisms to detect niche-specific signals, we analyzed the phylogenetic distribution of nearly 5,000 histidine protein kinases from 207 sequenced prokaryotic genomes. We found that many genomes carry a large repertoire of recently evolved signaling genes, which may reflect selective pressure to adapt to new environmental conditions. Both lineage-specific gene family expansion and horizontal gene transfer play major roles in the introduction of new histidine kinases into genomes; however, there are differences in how these two evolutionary forces act. Genes imported via horizontal transfer are more likely to retain their original functionality as inferred from a similar complement of signaling domains, while gene family expansion accompanied by domain shuffling appears to be a major source of novel genetic diversity. Family expansion is the dominant source of new histidine kinase genes in the genomes most enriched in signaling proteins, and detailed analysis reveals that divergence in domain structure and changes in expression patterns are hallmarks of recent expansions. Finally, while these two modes of gene acquisition are widespread across bacterial taxa, there are clear species-specific preferences for which mode is used. PMID:17083272

Role of Fatty Acid Kinase in Cellular Lipid Homeostasis and SaeRS-Dependent Virulence Factor Expression in Staphylococcus aureus.

PubMed

Ericson, Megan E; Subramanian, Chitra; Frank, Matthew W; Rock, Charles O

2017-08-01

The SaeRS two-component system is a master activator of virulence factor transcription in Staphylococcus aureus , but the cellular factors that control its activity are unknown. Fatty acid (FA) kinase is a two-component enzyme system required for extracellular FA uptake and SaeRS activity. Here, we demonstrate the existence of an intracellular nonesterified FA pool in S. aureus that is elevated in strains lacking FA kinase activity. SaeRS-mediated transcription is restored in FA kinase-negative strains when the intracellular FA pool is reduced either by growth with FA-depleted bovine serum albumin to extract the FA into the medium or by the heterologous expression of Neisseria gonorrhoeae acyl-acyl carrier protein synthetase to activate FA for phospholipid synthesis. These data show that FAs act as negative regulators of SaeRS signaling, and FA kinase activates SaeRS-dependent virulence factor production by lowering inhibitory FA levels. Thus, FA kinase plays a role in cellular lipid homeostasis by activating FA for incorporation into phospholipid, and it indirectly regulates SaeRS signaling by maintaining a low intracellular FA pool. IMPORTANCE The SaeRS two-component system is a master transcriptional activator of virulence factor production in response to the host environment in S. aureus , and strains lacking FA kinase have severely attenuated SaeRS-dependent virulence factor transcription. FA kinase is required for the activation of exogenous FAs, and it plays a role in cellular lipid homeostasis by recycling cellular FAs into the phospholipid biosynthetic pathway. Activation of the sensor kinase, SaeS, is mediated by its membrane anchor domain, and the FAs which accumulate in FA kinase knockout strains are potent inhibitors of SaeS-dependent signaling. This work identifies FAs as physiological effectors for the SaeRS system and reveals a connection between cellular lipid homeostasis and the regulation of virulence factor transcription. FA kinase is widely distributed in Gram-positive bacteria, suggesting similar roles for FA kinase in these organisms. Copyright © 2017 Ericson et al.

The Vlasov-Poisson-Boltzmann System for a Disparate Mass Binary Mixture

NASA Astrophysics Data System (ADS)

Duan, Renjun; Liu, Shuangqian

2017-11-01

The Vlasov-Poisson-Boltzmann system is often used to govern the motion of plasmas consisting of electrons and ions with disparate masses when collisions of charged particles are described by the two-component Boltzmann collision operator. The perturbation theory of the system around global Maxwellians recently has been well established in Guo (Commun Pure Appl Math 55:1104-1135, 2002). It should be more interesting to further study the existence and stability of nontrivial large time asymptotic profiles for the system even with slab symmetry in space, particularly understanding the effect of the self-consistent potential on the non-trivial long-term dynamics of the binary system. In this paper, we consider the problem in the setting of rarefaction waves. The analytical tool is based on the macro-micro decomposition introduced in Liu et al. (Physica D 188(3-4):178-192, 2004) that we have been able to develop for the case of the two-component Boltzmann equations around local bi-Maxwellians. Our focus is to explore how the disparate masses and charges of particles play a role in the analysis of the approach of the complex coupling system time-asymptotically toward a non-constant equilibrium state whose macroscopic quantities satisfy the quasineutral nonisentropic Euler system.

Coupling the Community Atmospheric Model (CAM) with the Statistical Spectral Interpolation (SSI) System under ESMF

NASA Technical Reports Server (NTRS)

daSilva, Arlindo

2004-01-01

The first set of interoperability experiments illustrates the role ESMF can play in integrating the national Earth science resources. Using existing data assimilation technology from NCEP and the National Weather Service, the Community Atmosphere Model (CAM) was able to ingest conventional and remotely sensed observations, a capability that could open the door to using CAM for weather as well as climate prediction. CAM, which includes land surface capabilities, was developed by NCAR, with key components from GSFC. In this talk we will describe the steps necessary for achieving the coupling of these two systems.

Complement component 4

MedlinePlus

... of a certain protein. This protein is part of the complement system. The complement system is a group of proteins ... system and play a role in the development of inflammation. The complement system protects the body from infections, dead cells and ...

A Comparative Study of the Proposed Models for the Components of the National Health Information System

PubMed Central

Ahmadi, Maryam; Damanabi, Shahla; Sadoughi, Farahnaz

2014-01-01

Introduction: National Health Information System plays an important role in ensuring timely and reliable access to Health information, which is essential for strategic and operational decisions that improve health, quality and effectiveness of health care. In other words, using the National Health information system you can improve the quality of health data, information and knowledge used to support decision making at all levels and areas of the health sector. Since full identification of the components of this system – for better planning and management influential factors of performanceseems necessary, therefore, in this study different attitudes towards components of this system are explored comparatively. Methods: This is a descriptive and comparative kind of study. The society includes printed and electronic documents containing components of the national health information system in three parts: input, process and output. In this context, search for information using library resources and internet search were conducted, and data analysis was expressed using comparative tables and qualitative data. Results: The findings showed that there are three different perspectives presenting the components of national health information system Lippeveld and Sauerborn and Bodart model in 2000, Health Metrics Network (HMN) model from World Health Organization in 2008, and Gattini’s 2009 model. All three models outlined above in the input (resources and structure) require components of management and leadership, planning and design programs, supply of staff, software and hardware facilities and equipment. Plus, in the “process” section from three models, we pointed up the actions ensuring the quality of health information system, and in output section, except for Lippeveld Model, two other models consider information products and use and distribution of information as components of the national health information system. Conclusion: the results showed that all the three models have had a brief discussion about the components of health information in input section. But Lippeveld model has overlooked the components of national health information in process and output sections. Therefore, it seems that the health measurement model of network has a comprehensive presentation for the components of health system in all three sections-input, process and output. PMID:24825937

A comparative study of the proposed models for the components of the national health information system.

PubMed

Ahmadi, Maryam; Damanabi, Shahla; Sadoughi, Farahnaz

2014-04-01

National Health Information System plays an important role in ensuring timely and reliable access to Health information, which is essential for strategic and operational decisions that improve health, quality and effectiveness of health care. In other words, using the National Health information system you can improve the quality of health data, information and knowledge used to support decision making at all levels and areas of the health sector. Since full identification of the components of this system - for better planning and management influential factors of performanceseems necessary, therefore, in this study different attitudes towards components of this system are explored comparatively. This is a descriptive and comparative kind of study. The society includes printed and electronic documents containing components of the national health information system in three parts: input, process and output. In this context, search for information using library resources and internet search were conducted, and data analysis was expressed using comparative tables and qualitative data. The findings showed that there are three different perspectives presenting the components of national health information system Lippeveld and Sauerborn and Bodart model in 2000, Health Metrics Network (HMN) model from World Health Organization in 2008, and Gattini's 2009 model. All three models outlined above in the input (resources and structure) require components of management and leadership, planning and design programs, supply of staff, software and hardware facilities and equipment. Plus, in the "process" section from three models, we pointed up the actions ensuring the quality of health information system, and in output section, except for Lippeveld Model, two other models consider information products and use and distribution of information as components of the national health information system. the results showed that all the three models have had a brief discussion about the components of health information in input section. But Lippeveld model has overlooked the components of national health information in process and output sections. Therefore, it seems that the health measurement model of network has a comprehensive presentation for the components of health system in all three sections-input, process and output.

Modular cell biology: retroactivity and insulation

PubMed Central

Del Vecchio, Domitilla; Ninfa, Alexander J; Sontag, Eduardo D

2008-01-01

Modularity plays a fundamental role in the prediction of the behavior of a system from the behavior of its components, guaranteeing that the properties of individual components do not change upon interconnection. Just as electrical, hydraulic, and other physical systems often do not display modularity, nor do many biochemical systems, and specifically, genetic networks. Here, we study the effect of interconnections on the input–output dynamic characteristics of transcriptional components, focusing on a property, which we call ‘retroactivity', that plays a role analogous to non-zero output impedance in electrical systems. In transcriptional networks, retroactivity is large when the amount of transcription factor is comparable to, or smaller than, the amount of promoter-binding sites, or when the affinity of such binding sites is high. To attenuate the effect of retroactivity, we propose a feedback mechanism inspired by the design of amplifiers in electronics. We introduce, in particular, a mechanism based on a phosphorylation–dephosphorylation cycle. This mechanism enjoys a remarkable insulation property, due to the fast timescales of the phosphorylation and dephosphorylation reactions. PMID:18277378

Complement component 3 (C3)

MedlinePlus

... of a certain protein. This protein is part of the complement system. The complement system is a group of proteins ... system and play a role in the development of inflammation. The complement system protects the body from infections, dead cells and ...

The Legionella IcmS-IcmW protein complex is important for Dot/Icm-mediated protein translocation.

PubMed

Ninio, Shira; Zuckman-Cholon, Deborah M; Cambronne, Eric D; Roy, Craig R

2005-02-01

The intracellular pathogen Legionella pneumophila can infect and replicate within macrophages of a human host. To establish infection, Legionella require the Dot/Icm secretion system to inject protein substrates directly into the host cell cytoplasm. The mechanism by which substrate proteins are engaged and translocated by the Dot/Icm system is not well understood. Here we show that two cytosolic components of the Dot/Icm secretion machinery, the proteins IcmS and IcmW, play an important role in substrate translocation. Biochemical analysis indicates that IcmS and IcmW form a stable protein complex. In Legionella, the IcmW protein is rapidly degraded in the absence of the IcmS protein. Substrate proteins translocated into mammalian host cells by the Dot/Icm system were identified using the IcmW protein as bait in a yeast two-hybrid screen. It was determined that the IcmS-IcmW complex interacts with these substrates and plays an important role in translocation of these proteins into mammalian cells. These data are consistent with the IcmS-IcmW complex being involved in the recognition and Dot/Icm-dependent translocation of substrate proteins during Legionella infection of host cells.

Laser interferometer for space-based mapping of Earth's gravity field

NASA Astrophysics Data System (ADS)

Dehne, Marina; Sheard, Benjamin; Gerberding, Oliver; Mahrdt, Christoph; Heinzel, Gerhard; Danzmann, Karsten

2010-05-01

Laser interferometry will play a key role in the next generation of GRACE-type satellite gravity missions. The measurement concepts for future missions include a heterodyne laser interferometer. Furthermore, it is favourable to use polarising components in the laser interferometer for beam splitting. In the first step the influence of these components on the interferometer sensitivity has been investigated. Additionally, a length stability on a nm-scale has been validated. The next step will include a performance test of an interferometric SST system in an active symmetric transponder setup including two lasers and two optical benches. The design and construction of a quasi-monolithic interferometer for comparing the interferometric performance of non-polarising and polarising optics will be discussed. The results of the interferometric readout of a heterodyne configuration together with polarising optics will be presented to fulfil the phase sensitivity requirement of 1nm/√Hz-- for a typical SSI scenario.

Standard metrics for a plug-and-play tracker

NASA Astrophysics Data System (ADS)

Antonisse, Jim; Young, Darrell

2012-06-01

The Motion Imagery Standards Board (MISB) has previously established a metadata "micro-architecture" for standards-based tracking. The intent of this work is to facilitate both the collaborative development of competent tracking systems, and the potentially distributed and dispersed execution of tracker system components in real-world execution environments. The approach standardizes a set of five quasi-sequential modules in image-based tracking. However, in order to make the plug-and-play architecture truly useful we need metrics associated with each module (so that, for instance, a researcher who "plugs in" a new component can ascertain whether he/she did better or worse with the component). This paper proposes the choice of a new, unifying set of metrics based on an informationtheoretic approach to tracking, which the MISB is nominating as DoD/IC/NATO standards.

Generalizing the extensibility of a dynamic geometry software

NASA Astrophysics Data System (ADS)

Herceg, Đorđe; Radaković, Davorka; Herceg, Dejana

2012-09-01

Plug-and-play visual components in a Dynamic Geometry Software (DGS) enable development of visually attractive, rich and highly interactive dynamic drawings. We are developing SLGeometry, a DGS that contains a custom programming language, a computer algebra system (CAS engine) and a graphics subsystem. The basic extensibility framework on SLGeometry supports dynamic addition of new functions from attribute annotated classes that implement runtime metadata registration in code. We present a general plug-in framework for dynamic importing of arbitrary Silverlight user interface (UI) controls into SLGeometry at runtime. The CAS engine maintains a metadata storage that describes each imported visual component and enables two-way communication between the expressions stored in the engine and the UI controls on the screen.

Evolutionary analysis and lateral gene transfer of two-component regulatory systems associated with heavy-metal tolerance in bacteria.

PubMed

Bouzat, Juan L; Hoostal, Matthew J

2013-05-01

Microorganisms have adapted intricate signal transduction mechanisms to coordinate tolerance to toxic levels of metals, including two-component regulatory systems (TCRS). In particular, both cop and czc operons are regulated by TCRS; the cop operon plays a key role in bacterial tolerance to copper, whereas the czc operon is involved in the efflux of cadmium, zinc, and cobalt from the cell. Although the molecular physiology of heavy metal tolerance genes has been extensively studied, their evolutionary relationships are not well-understood. Phylogenetic relationships among heavy-metal efflux proteins and their corresponding two-component regulatory proteins revealed orthologous and paralogous relationships from species divergences and ancient gene duplications. The presence of heavy metal tolerance genes on bacterial plasmids suggests these genes may be prone to spread through horizontal gene transfer. Phylogenetic inferences revealed nine potential examples of lateral gene transfer associated with metal efflux proteins and two examples for regulatory proteins. Notably, four of the examples suggest lateral transfer across major evolutionary domains. In most cases, differences in GC content in metal tolerance genes and their corresponding host genomes confirmed lateral gene transfer events. Three-dimensional protein structures predicted for the response regulators encoded by cop and czc operons showed a high degree of structural similarity with other known proteins involved in TCRS signal transduction, which suggests common evolutionary origins of functional phenotypes and similar mechanisms of action for these response regulators.

Influence of functional food components on gut health.

PubMed

Wan, Murphy L Y; Ling, K H; El-Nezami, Hani; Wang, M F

2018-01-30

Intestinal epithelial cells (IECs) lining the gastrointestinal tract establish a barrier between external environments and the internal milieu. An intact intestinal barrier maintains gut health and overall good health of the body by preventing from tissue injury, pathogen infection and disease development. When the intestinal barrier function is compromised, bacterial translocation can occur. Our gut microbiota also plays a fundamentally important role in health, for example, by maintaining intestinal barrier integrity, metabolism and modulating the immune system, etc. Any disruption of gut microbiota composition (also termed dysbiosis) can lead to various pathological conditions. In short, intestinal barrier and gut microbiota are two crucial factors affecting gut health. The gastrointestinal tract is a complex environment exposed to many dietary components and commensal bacteria. Dietary components are increasingly recognized to play various beneficial roles beyond basic nutrition, resulting in the development of the functional food concepts. Various dietary modifiers, including the consumption of live bacteria (probiotics) and ingestible food constituents such as prebiotics, as well as polyphenols or synbiotics (combinations of probiotics and prebiotics) are the most well characterized dietary bioactive compounds and have been demonstrated to beneficially impact the gut health and the overall well-being of the host. In this review we depict the roles of intestinal epithelium and gut microbiota in mucosal defence responses and the influence of certain functional food components on the modulation of gut health, with a particular focus on probiotics, prebiotics and polyphenols.

Beyond Valence and Magnitude: a Flexible Evaluative Coding System in the Brain

PubMed Central

Gu, Ruolei; Lei, Zhihui; Broster, Lucas; Wu, Tingting; Jiang, Yang; Luo, Yue-jia

2013-01-01

Outcome evaluation is a cognitive process that plays an important role in our daily lives. In most paradigms utilized in the field of experimental psychology, outcome valence and outcome magnitude are the two major features investigated. The classical “independent coding model” suggest that outcome valence and outcome magnitude are evaluated by separate neural mechanisms that may be mapped onto discrete event-related potential (ERP) components: feedback-related negativity (FRN) and the P3, respectively. To examine this model, we presented outcome valence and magnitude sequentially rather than simultaneously. The results reveal that when only outcome valence or magnitude is known, both the FRN and the P3 encode that outcome feature; when both aspects of outcome are known, the cognitive functions of the two components dissociate: the FRN responds to the information available in the current context, while the P3 pattern depends on outcome presentation sequence. The current study indicates that the human evaluative system, indexed in part by the FRN and the P3, is more flexible than previous theories suggested. PMID:22019775

Semiconductor devices for entangled photon pair generation: a review

NASA Astrophysics Data System (ADS)

Orieux, Adeline; Versteegh, Marijn A. M.; Jöns, Klaus D.; Ducci, Sara

2017-07-01

Entanglement is one of the most fascinating properties of quantum mechanical systems; when two particles are entangled the measurement of the properties of one of the two allows the properties of the other to be instantaneously known, whatever the distance separating them. In parallel with fundamental research on the foundations of quantum mechanics performed on complex experimental set-ups, we assist today with bourgeoning of quantum information technologies bound to exploit entanglement for a large variety of applications such as secure communications, metrology and computation. Among the different physical systems under investigation, those involving photonic components are likely to play a central role and in this context semiconductor materials exhibit a huge potential in terms of integration of several quantum components in miniature chips. In this article we review the recent progress in the development of semiconductor devices emitting entangled photons. We will present the physical processes allowing the generation of entanglement and the tools to characterize it; we will give an overview of major recent results of the last few years and highlight perspectives for future developments.

The two-component system GrvRS (EtaRS) regulates ace expression in Enterococcus faecalis OG1RF.

PubMed

Roh, Jung Hyeob; Singh, Kavindra V; La Rosa, Sabina Leanti; Cohen, Ana Luisa V; Murray, Barbara E

2015-01-01

Expression of ace (adhesin to collagen of Enterococcus faecalis), encoding a virulence factor in endocarditis and urinary tract infection models, has been shown to increase under certain conditions, such as in the presence of serum, bile salts, urine, and collagen and at 46 °C. However, the mechanism of ace/Ace regulation under different conditions is still unknown. In this study, we identified a two-component regulatory system GrvRS as the main regulator of ace expression under these stress conditions. Using Northern hybridization and β-galactosidase assays of an ace promoter-lacZ fusion, we found transcription of ace to be virtually absent in a grvR deletion mutant under the conditions that increase ace expression in wild-type OG1RF and in the complemented strain. Moreover, a grvR mutant revealed decreased collagen binding and biofilm formation as well as attenuation in a murine urinary tract infection model. Here we show that GrvR plays a major role in control of ace expression and E. faecalis virulence. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

A Plug and Play GNC Architecture Using FPGA Components

NASA Technical Reports Server (NTRS)

KrishnaKumar, K.; Kaneshige, J.; Waterman, R.; Pires, C.; Ippoloito, C.

2005-01-01

The goal of Plug and Play, or PnP, is to allow hardware and software components to work together automatically, without requiring manual setup procedures. As a result, new or replacement hardware can be plugged into a system and automatically configured with the appropriate resource assignments. However, in many cases it may not be practical or even feasible to physically replace hardware components. One method for handling these types of situations is through the incorporation of reconfigurable hardware such as Field Programmable Gate Arrays, or FPGAs. This paper describes a phased approach to developing a Guidance, Navigation, and Control (GNC) architecture that expands on the traditional concepts of PnP, in order to accommodate hardware reconfiguration without requiring detailed knowledge of the hardware. This is achieved by establishing a functional based interface that defines how the hardware will operate, and allow the hardware to reconfigure itself. The resulting system combines the flexibility of manipulating software components with the speed and efficiency of hardware.

Two-component fluid membranes near repulsive walls: Linearized hydrodynamics of equilibrium and nonequilibrium states.

PubMed

Sankararaman, Sumithra; Menon, Gautam I; Sunil Kumar, P B

2002-09-01

We study the linearized hydrodynamics of a two-component fluid membrane near a repulsive wall, using a model that incorporates curvature-concentration coupling as well as hydrodynamic interactions. This model is a simplified version of a recently proposed one [J.-B. Manneville et al., Phys. Rev. E 64, 021908 (2001)] for nonequilibrium force centers embedded in fluid membranes, such as light-activated bacteriorhodopsin pumps incorporated in phospholipid egg phosphatidyl choline (EPC) bilayers. The pump-membrane system is modeled as an impermeable, two-component bilayer fluid membrane in the presence of an ambient solvent, in which one component, representing active pumps, is described in terms of force dipoles displaced with respect to the bilayer midpoint. We first discuss the case in which such pumps are rendered inactive, computing the mode structure in the bulk as well as the modification of hydrodynamic properties by the presence of a nearby wall. These results should apply, more generally, to equilibrium fluid membranes comprised of two components, in which the effects of curvature-concentration coupling are significant, above the threshold for phase separation. We then discuss the fluctuations and mode structure in the steady state of active two-component membranes near a repulsive wall. We find that proximity to the wall smoothens membrane height fluctuations in the stable regime, resulting in a logarithmic scaling of the roughness even for initially tensionless membranes. This explicitly nonequilibrium result is a consequence of the incorporation of curvature-concentration coupling in our hydrodynamic treatment. This result also indicates that earlier scaling arguments which obtained an increase in the roughness of active membranes near repulsive walls upon neglecting the role played by such couplings may need to be reevaluated.

Linear response to nonstationary random excitation.

NASA Technical Reports Server (NTRS)

Hasselman, T.

1972-01-01

Development of a method for computing the mean-square response of linear systems to nonstationary random excitation of the form given by y(t) = f(t) x(t), in which x(t) = a stationary process and f(t) is deterministic. The method is suitable for application to multidegree-of-freedom systems when the mean-square response at a point due to excitation applied at another point is desired. Both the stationary process, x(t), and the modulating function, f(t), may be arbitrary. The method utilizes a fundamental component of transient response dependent only on x(t) and the system, and independent of f(t) to synthesize the total response. The role played by this component is analogous to that played by the Green's function or impulse response function in the convolution integral.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Jing-Yuan; Son, Jun Ho; Wang, Chao

The idea of statistical transmutation plays a crucial role in descriptions of the fractional quantum Hall effect. However, a recently conjectured duality between a critical boson and a massless two-component Dirac fermion extends this notion to gapless systems. This duality sheds light on highly nontrivial problems such as the half-filled Landau level, the superconductor-insulator transition, and surface states of strongly coupled topological insulators. Although this boson-fermion duality has undergone many consistency checks, it has remained unproven. Here, we describe the duality in a nonperturbative fashion using an exact UV mapping of partition functions on a 3D Euclidean lattice.

An investigation of prior knowledge in Automatic Music Transcription systems.

PubMed

Cazau, Dorian; Revillon, Guillaume; Krywyk, Julien; Adam, Olivier

2015-10-01

Automatic transcription of music is a long-studied research field with many operational systems available commercially. In this paper, a generic transcription system able to host various prior knowledge parameters has been developed, followed by an in-depth investigation of their impact on music transcription. Explicit links between musical knowledge and algorithmic formalism have been made. Musical knowledge covers classes of timbre, musicology, and playing style of an instrument repertoire. An evaluation sound corpus gathering musical pieces played by human performers from three different instrument repertoires, namely, classical piano, steel-string acoustic guitar, and the marovany zither from Madagascar, has been developed. The different components of musical knowledge have been successively incorporated in a complete transcription system, consisting mainly of a Probabilistic Latent Component Analysis algorithm post-processed with a Hidden Markov Model, and their impact on transcription results have been comparatively evaluated.

System identification of jet engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sugiyama, N.

2000-01-01

System identification plays an important role in advanced control systems for jet engines, in which controls are performed adaptively using data from the actual engine and the identified engine. An identification technique for jet engine using the Constant Gain Extended Kalman Filter (CGEKF) is described. The filter is constructed for a two-spool turbofan engine. The CGEKF filter developed here can recognize parameter change in engine components and estimate unmeasurable variables over whole flight conditions. These capabilities are useful for an advanced Full Authority Digital Electric Control (FADEC). Effects of measurement noise and bias, effects of operating point and unpredicted performancemore » change are discussed. Some experimental results using the actual engine are shown to evaluate the effectiveness of CGEKF filter.« less

Chloroplast two-component systems: evolution of the link between photosynthesis and gene expression

PubMed Central

Puthiyaveetil, Sujith; Allen, John F.

2009-01-01

Two-component signal transduction, consisting of sensor kinases and response regulators, is the predominant signalling mechanism in bacteria. This signalling system originated in prokaryotes and has spread throughout the eukaryotic domain of life through endosymbiotic, lateral gene transfer from the bacterial ancestors and early evolutionary precursors of eukaryotic, cytoplasmic, bioenergetic organelles—chloroplasts and mitochondria. Until recently, it was thought that two-component systems inherited from an ancestral cyanobacterial symbiont are no longer present in chloroplasts. Recent research now shows that two-component systems have survived in chloroplasts as products of both chloroplast and nuclear genes. Comparative genomic analysis of photosynthetic eukaryotes shows a lineage-specific distribution of chloroplast two-component systems. The components and the systems they comprise have homologues in extant cyanobacterial lineages, indicating their ancient cyanobacterial origin. Sequence and functional characteristics of chloroplast two-component systems point to their fundamental role in linking photosynthesis with gene expression. We propose that two-component systems provide a coupling between photosynthesis and gene expression that serves to retain genes in chloroplasts, thus providing the basis of cytoplasmic, non-Mendelian inheritance of plastid-associated characters. We discuss the role of this coupling in the chronobiology of cells and in the dialogue between nuclear and cytoplasmic genetic systems. PMID:19324807

Chloroplast two-component systems: evolution of the link between photosynthesis and gene expression.

PubMed

Puthiyaveetil, Sujith; Allen, John F

2009-06-22

Two-component signal transduction, consisting of sensor kinases and response regulators, is the predominant signalling mechanism in bacteria. This signalling system originated in prokaryotes and has spread throughout the eukaryotic domain of life through endosymbiotic, lateral gene transfer from the bacterial ancestors and early evolutionary precursors of eukaryotic, cytoplasmic, bioenergetic organelles-chloroplasts and mitochondria. Until recently, it was thought that two-component systems inherited from an ancestral cyanobacterial symbiont are no longer present in chloroplasts. Recent research now shows that two-component systems have survived in chloroplasts as products of both chloroplast and nuclear genes. Comparative genomic analysis of photosynthetic eukaryotes shows a lineage-specific distribution of chloroplast two-component systems. The components and the systems they comprise have homologues in extant cyanobacterial lineages, indicating their ancient cyanobacterial origin. Sequence and functional characteristics of chloroplast two-component systems point to their fundamental role in linking photosynthesis with gene expression. We propose that two-component systems provide a coupling between photosynthesis and gene expression that serves to retain genes in chloroplasts, thus providing the basis of cytoplasmic, non-Mendelian inheritance of plastid-associated characters. We discuss the role of this coupling in the chronobiology of cells and in the dialogue between nuclear and cytoplasmic genetic systems.

Interactive effects of global change factors on soil respiration and its components: a meta-analysis.

PubMed

Zhou, Lingyan; Zhou, Xuhui; Shao, Junjiong; Nie, Yuanyuan; He, Yanghui; Jiang, Liling; Wu, Zhuoting; Hosseini Bai, Shahla

2016-09-01

As the second largest carbon (C) flux between the atmosphere and terrestrial ecosystems, soil respiration (Rs) plays vital roles in regulating atmospheric CO2 concentration ([CO2 ]) and climatic dynamics in the earth system. Although numerous manipulative studies and a few meta-analyses have been conducted to determine the responses of Rs and its two components [i.e., autotrophic (Ra) and heterotrophic (Rh) respiration] to single global change factors, the interactive effects of the multiple factors are still unclear. In this study, we performed a meta-analysis of 150 multiple-factor (≥2) studies to examine the main and interactive effects of global change factors on Rs and its two components. Our results showed that elevated [CO2 ] (E), nitrogen addition (N), irrigation (I), and warming (W) induced significant increases in Rs by 28.6%, 8.8%, 9.7%, and 7.1%, respectively. The combined effects of the multiple factors, EN, EW, DE, IE, IN, IW, IEW, and DEW, were also significantly positive on Rs to a greater extent than those of the single-factor ones. For all the individual studies, the additive interactions were predominant on Rs (90.6%) and its components (≈70.0%) relative to synergistic and antagonistic ones. However, the different combinations of global change factors (e.g., EN, NW, EW, IW) indicated that the three types of interactions were all important, with two combinations for synergistic effects, two for antagonistic, and five for additive when at least eight independent experiments were considered. In addition, the interactions of elevated [CO2 ] and warming had opposite effects on Ra and Rh, suggesting that different processes may influence their responses to the multifactor interactions. Our study highlights the crucial importance of the interactive effects among the multiple factors on Rs and its components, which could inform regional and global models to assess the climate-biosphere feedbacks and improve predictions of the future states of the ecological and climate systems. © 2016 John Wiley & Sons Ltd.

Two-component gravitating systems and the red giant-like structure

NASA Technical Reports Server (NTRS)

Fujimoto, Masayuki Y.; Tomisaka, Kohji

1992-01-01

The present study investigates the equilibria and evolution of gravitating systems composed of two components by approximating their equations of states to polytropes. The structures are explored in hydrostatic equilibrium systematically under the condition that two components interact with each other only through gravity. The systems are found to be characterized by four parameters, the ratio of central densities and the ratio of central thermal energies per unit mass, and the polytropic indices of two components. If the central density is much higher, the structure is little affected by the presence of the other component. If the difference in the central thermal energies is smaller than specified by beta-cri, the system adopts an equilibrium configuration for any mass ratio. Two-component systems necessarily evolve to have the red giantlike structure if one component suffers cooling faster than the other. It is concluded that the red giant structure is a general characteristic of gravitating systems for which there is an appropriate mechanism to decouple the constituent into the hotter and cooler components.

Integration of a complex regulatory cascade involving the SirA/BarA and Csr global regulatory systems that controls expression of the Salmonella SPI-1 and SPI-2 virulence regulons through HilD.

PubMed

Martínez, Luary C; Yakhnin, Helen; Camacho, Martha I; Georgellis, Dimitris; Babitzke, Paul; Puente, José L; Bustamante, Víctor H

2011-06-01

Salmonella pathogenicity islands 1 and 2 (SPI-1 and SPI-2) play key roles in the pathogenesis of Salmonella enterica. Previously, we showed that when Salmonella grows in Luria-Bertani medium, HilD, encoded in SPI-1, first induces the expression of hilA, located in SPI-1, and subsequently of the ssrAB operon, located in SPI-2. These genes code for HilA and the SsrA/B two-component system, the positive regulators of the SPI-1 and SPI-2 regulons respectively. In this study, we demonstrate that CsrA, a global regulatory RNA binding protein, post-transcriptionally regulates hilD expression by directly binding near the Shine-Dalgarno and translation initiation codon sequences of the hilD mRNA, preventing its translation and leading to its accelerated turnover. Negative regulation is counteracted by the global SirA/BarA two-component system, which directly activates the expression of CsrB and CsrC, two non-coding regulatory RNAs that sequester CsrA, thereby preventing it from binding to its target mRNAs. Our results illustrate the integration of global and specific regulators into a multifactorial regulatory cascade controlling the expression of virulence genes acquired by horizontal transfer events. © 2011 Blackwell Publishing Ltd.

Complexation in two-component chlortetracycline-melanin solutions

NASA Astrophysics Data System (ADS)

Lapina, V. A.; Pershukevich, P. P.; Dontsov, A. E.; Bel'Kov, M. V.

2008-01-01

The spectra and kinetics of fluorescence of two-component solutions of the chlortetracycline (CHTC)-DOPA-melanin (melanin or ME) system in water have been investigated. The data obtained have been compared to similar data for solutions of CHTC-melanosome from bull eye (MB), which contains natural melanin, in K-phosphate buffer at pH 7.4. The overall results indicate the occurrence of complexation between molecules of CHTC and ME as they are being excited. The studies of complexation in the solution of CHTC-MB in the buffer are complicated by the formation of a CHTC-buffer complex. The effect of optical radiation in the range 330-750 nm on the CHTC-ME complex shows selectivity: the greatest change in the spectrum occurs when the wavelength of the exciting radiation coincides with the long-wavelength band maximum of the fluorescence excitation spectrum of the CHTC-ME complex in aqueous solution. In this range, CHTC and especially ME show high photochemical stability. The nature of the radiation effect on the studied compounds in the hard UV range (λ < 330 nm) differs greatly from that in the range 330-750 nm. It is apparently accompanied by significant photochemical transmutations of all system components. By comparing the characteristics of the CHTC-ME systems with those of the related drug doxycycline (DC-ME), the conclusion has been made that the chlorine atom plays a vital role in formation of the short-wavelength band in the fluorescence spectrum of the CHTC-ME complex.

Using Publish-Subscribe Messaging for System Status and Automation

NASA Technical Reports Server (NTRS)

Smith, Danford S.

2015-01-01

The NASA Goddard Mission Services Evolution Center (GMSEC) system is a message-based plug-and-play open system architecture used in many of NASA mission operations centers. This presentation will focus on the use of GMSEC standard messages to report and analyze the status of a system and enable the automation of the system's components. In GMSEC systems, each component reports its status using a keep-alive message and also publishes status and activities as log messages. In addition, the components can accept functional directive messages from the GMSEC message bus. Over the past several years, development teams have found ways to utilize these messages to create innovative display pages and increasingly sophisticated approaches to automation. This presentation will show the flexibility and value of the message-based approach to system awareness and automation.

Quantifying the benefits of urban forest systems as a component of the green infrastructure stormwater treatment network

Treesearch

Eric Kuehler; Jon Hathaway; Andrew Tirpak

2017-01-01

The use of green infrastructure for reducing stormwater runoff is increasingly common. One under‐studied component of the green infrastructure network is the urban forest system. Trees can play an important role as the “first line of defense” for restoring more natural hydrologic regimes in urban watersheds by intercepting rainfall, delaying runoff, infiltrating, and...

Effects of Role-Play and Mindfulness Training on Enhancing the Family Friendliness of the Admissions Treatment Team Process.

ERIC Educational Resources Information Center

Singh, Nirbhay N.; Wechsler, Hollis A.; Curtis, W. John; Sabaawi, Mohamed; Myers, Rachel E.; Singh, Subhashni D.

2002-01-01

This article describes two studies that evaluated training intended to improve the family friendliness of five components of the admission treatment team process at an inpatient child and adolescent psychiatric hospital. While role-play training did not improve family friendliness, mindfulness training enhanced the family friendliness of all five…

A two-dimensional electrophoretic profile of the proteins secreted by Herbaspirillum seropedicae strain Z78.

PubMed

Chaves, Daniela Fojo Seixas; de Souza, Emanuel Maltempi; Monteiro, Rose Adele; de Oliveira Pedrosa, Fábio

2009-11-02

Herbaspirillum seropedicae is an endophytic bacterium that associates with rice, sugarcane and other economically important crops. Secreted proteins play a key role in the plant-bacterial interaction. Using 2D electrophoresis and peptide mass fingerprint mass spectrometry, 63 protein spots representing 41 different secreted proteins were identified during growth of H. seropedicae under nitrogen-sufficient conditions. In silico analysis showed that 25.4% of the proteins had signal peptides and 15.9% were predicted to be non-classically secreted. Among the most abundant were flagellar components and ABC-type transport system proteins. Nine secreted proteins had also been identified in the cellular proteome, suggesting that they also play a role in the extracellular environment. No type III secreted proteins were detected by comparison of the wild type strain with an hrcN mutant strain.

Preparative isolation of a cytotoxic principle of a forest mushroom Suillus luteus by sodium dodecyl sulfate based "salting-in" countercurrent chromatography.

PubMed

Yang, Zhi; Hu, Xueqian; Wu, Shihua

2016-02-01

In the course of screening new anticancer natural products, an edible forest mushroom Suillus luteus (L. Ex Franch). Gray was found to have potent cytotoxicity against several human cancer cells. However, the lipophilic sample made some countercurrent chromatography solvent systems emulsify, which caused difficulties in the separation of its cytotoxic components. Here, we found that the addition of an organic salt sodium dodecyl sulfate could efficiently shorten the settling time of the mushroom sample solutions by eliminating the emulsification of two-phase solvent systems. Moreover, we found that sodium dodecyl sulfate could play a new "salting-in" role and made the partition coefficients of the solutes decrease with the increased concentrations. Thus, a sodium dodecyl sulfate based salting-in countercurrent chromatography method has been successfully established for the first time for preparative isolation of a cytotoxic principle of the mushroom. The active component was identified as isosuillin. Whole results indicated that sodium dodecyl sulfate could be used as an efficient salting-in reagent for two-phase solvent system selection and targeted countercurrent chromatography isolation. It is very useful for current natural products isolation and drug discovery. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lax representations for matrix short pulse equations

NASA Astrophysics Data System (ADS)

Popowicz, Z.

2017-10-01

The Lax representation for different matrix generalizations of Short Pulse Equations (SPEs) is considered. The four-dimensional Lax representations of four-component Matsuno, Feng, and Dimakis-Müller-Hoissen-Matsuno equations are obtained. The four-component Feng system is defined by generalization of the two-dimensional Lax representation to the four-component case. This system reduces to the original Feng equation, to the two-component Matsuno equation, or to the Yao-Zang equation. The three-component version of the Feng equation is presented. The four-component version of the Matsuno equation with its Lax representation is given. This equation reduces the new two-component Feng system. The two-component Dimakis-Müller-Hoissen-Matsuno equations are generalized to the four-parameter family of the four-component SPE. The bi-Hamiltonian structure of this generalization, for special values of parameters, is defined. This four-component SPE in special cases reduces to the new two-component SPE.

An assembly system based on industrial robot with binocular stereo vision

NASA Astrophysics Data System (ADS)

Tang, Hong; Xiao, Nanfeng

2017-01-01

This paper proposes an electronic part and component assembly system based on an industrial robot with binocular stereo vision. Firstly, binocular stereo vision with a visual attention mechanism model is used to get quickly the image regions which contain the electronic parts and components. Secondly, a deep neural network is adopted to recognize the features of the electronic parts and components. Thirdly, in order to control the end-effector of the industrial robot to grasp the electronic parts and components, a genetic algorithm (GA) is proposed to compute the transition matrix and the inverse kinematics of the industrial robot (end-effector), which plays a key role in bridging the binocular stereo vision and the industrial robot. Finally, the proposed assembly system is tested in LED component assembly experiments, and the results denote that it has high efficiency and good applicability.

Nonlinear low frequency electrostatic structures in a magnetized two-component auroral plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rufai, O. R., E-mail: rajirufai@gmail.com; Scientific Computing, Memorial University of Newfoundland, St John's, Newfoundland and Labrador A1C 5S7; Bharuthram, R., E-mail: rbharuthram@uwc.ac.za

2016-03-15

Finite amplitude nonlinear ion-acoustic solitons, double layers, and supersolitons in a magnetized two-component plasma composed of adiabatic warm ions fluid and energetic nonthermal electrons are studied by employing the Sagdeev pseudopotential technique and assuming the charge neutrality condition at equilibrium. The model generates supersoliton structures at supersonic Mach numbers regime in addition to solitons and double layers, whereas in the unmagnetized two-component plasma case only, soliton and double layer solutions can be obtained. Further investigation revealed that wave obliqueness plays a critical role for the evolution of supersoliton structures in magnetized two-component plasmas. In addition, the effect of ion temperaturemore » and nonthermal energetic electron tends to decrease the speed of oscillation of the nonlinear electrostatic structures. The present theoretical results are compared with Viking satellite observations.« less

Effect of cooler electrons on a compressive ion acoustic solitary wave in a warm ion plasma — Forbidden regions, double layers, and supersolitons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, S. S., E-mail: sukti@iigs.iigm.res.in; Sekar Iyengar, A. N.

It is observed that the presence of a minority component of cooler electrons in a three component plasma plays a deterministic role in the evolution of solitary waves, double layers, or the newly discovered structures called supersolitons. The inclusion of the cooler component of electrons in a single electron plasma produces sharp increase in nonlinearity in spite of a decrease in the overall energy of the system. The effect maximizes at certain critical value of the number density of the cooler component (typically 15%–20%) giving rise to a hump in the amplitude variation profile. For larger amplitudes, the hump leadsmore » to a forbidden region in the ambient cooler electron concentration which dissociates the overall existence domain of solitary wave solutions in two distinct parameter regime. It is observed that an inclusion of the cooler component of electrons as low as < 1% affects the plasma system significantly resulting in compressive double layers. The solution is further affected by the cold to hot electron temperature ratio. In an adequately hotter bulk plasma (i.e., moderately low cold to hot electron temperature ratio), the parameter domain of compressive double layers is bounded by a sharp discontinuity in the corresponding amplitude variation profile which may lead to supersolitons.« less

Quantifying the Relative Contributions of Divisive and Subtractive Feedback to Rhythm Generation

PubMed Central

Tabak, Joël; Rinzel, John; Bertram, Richard

2011-01-01

Biological systems are characterized by a high number of interacting components. Determining the role of each component is difficult, addressed here in the context of biological oscillations. Rhythmic behavior can result from the interplay of positive feedback that promotes bistability between high and low activity, and slow negative feedback that switches the system between the high and low activity states. Many biological oscillators include two types of negative feedback processes: divisive (decreases the gain of the positive feedback loop) and subtractive (increases the input threshold) that both contribute to slowly move the system between the high- and low-activity states. Can we determine the relative contribution of each type of negative feedback process to the rhythmic activity? Does one dominate? Do they control the active and silent phase equally? To answer these questions we use a neural network model with excitatory coupling, regulated by synaptic depression (divisive) and cellular adaptation (subtractive feedback). We first attempt to apply standard experimental methodologies: either passive observation to correlate the variations of a variable of interest to system behavior, or deletion of a component to establish whether a component is critical for the system. We find that these two strategies can lead to contradictory conclusions, and at best their interpretive power is limited. We instead develop a computational measure of the contribution of a process, by evaluating the sensitivity of the active (high activity) and silent (low activity) phase durations to the time constant of the process. The measure shows that both processes control the active phase, in proportion to their speed and relative weight. However, only the subtractive process plays a major role in setting the duration of the silent phase. This computational method can be used to analyze the role of negative feedback processes in a wide range of biological rhythms. PMID:21533065

The default network and self-generated thought: component processes, dynamic control, and clinical relevance

PubMed Central

Andrews-Hanna, Jessica R.; Smallwood, Jonathan; Spreng, R. Nathan

2014-01-01

Though only a decade has elapsed since the default network was first emphasized as being a large-scale brain system, recent years have brought great insight into the network’s adaptive functions. A growing theme highlights the default network as playing a key role in internally-directed—or self-generated—thought. Here, we synthesize recent findings from cognitive science, neuroscience, and clinical psychology to focus attention on two emerging topics as current and future directions surrounding the default network. First, we present evidence that self-generated thought is a multi-faceted construct whose component processes are supported by different subsystems within the network. Second, we highlight the dynamic nature of the default network, emphasizing its interaction with executive control systems when regulating aspects of internal thought. We conclude by discussing clinical implications of disruptions to the integrity of the network, and consider disorders when thought content becomes polarized or network interactions become disrupted or imbalanced. PMID:24502540

Synergy in Protein–Osmolyte Mixtures

PubMed Central

2014-01-01

Virtually all taxa use osmolytes to protect cells against biochemical stress. Osmolytes often occur in mixtures, such as the classical combination of urea with TMAO (trimethylamine N-oxide) in cartilaginous fish or the cocktail of at least six different osmolytes in the kidney. The concentration patterns of osmolyte mixtures found in vivo make it likely that synergy between them plays an important role. Using statistical mechanical n-component Kirkwood–Buff theory, we show from first principles that synergy in protein–osmolyte systems can arise from two separable sources: (1) mutual alteration of protein surface solvation and (2) effects mediated through bulk osmolyte chemical activities. We illustrate both effects in a four-component system with the experimental example of the unfolding of a notch ankyrin domain in urea–TMAO mixtures, which make urea a less effective denaturant and TMAO a more effective stabilizer. Protein surface effects are primarily responsible for this synergy. The specific patterns of surface solvation point to denatured state expansion as the main factor, as opposed to direct competition. PMID:25490052

Plant Pathogenesis-Related Proteins PR-10 and PR-14 as Components of Innate Immunity System and Ubiquitous Allergens.

PubMed

Finkina, Ekaterina I; Melnikova, Daria N; Bogdanov, Ivan V; Ovchinnikova, Tatiana V

2017-01-01

Pathogenesis-related (PR) proteins are components of innate immunity system in plants. They play an important role in plant defense against pathogens. Lipid transfer proteins (LTPs) and Bet v 1 homologs comprise of two separate families of PR-proteins. Both LTPs (PR-14) and Bet v 1 homologs (PR-10) are multifunctional small proteins involving in plant response to abiotic and biotic stress conditions. The representatives of these PR-protein families do not show any sequence similarity but have other common biochemical features such as low molecular masses, the presence of hydrophobic cavities, ligand binding properties, and antimicrobial activities. Besides, many members of PR-10 and PR-14 families are ubiquitous plant panallergens which are able to cause sensitization of human immune system and crossreactive allergic reactions to plant food and pollen. This review is aimed at comparative analysis of structure-functional and allergenic properties of the PR-10 and PR-14 families, as well as prospects for their medicinal application. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

High-speed Particle Image Velocimetry Near Surfaces

PubMed Central

Lu, Louise; Sick, Volker

2013-01-01

Multi-dimensional and transient flows play a key role in many areas of science, engineering, and health sciences but are often not well understood. The complex nature of these flows may be studied using particle image velocimetry (PIV), a laser-based imaging technique for optically accessible flows. Though many forms of PIV exist that extend the technique beyond the original planar two-component velocity measurement capabilities, the basic PIV system consists of a light source (laser), a camera, tracer particles, and analysis algorithms. The imaging and recording parameters, the light source, and the algorithms are adjusted to optimize the recording for the flow of interest and obtain valid velocity data. Common PIV investigations measure two-component velocities in a plane at a few frames per second. However, recent developments in instrumentation have facilitated high-frame rate (> 1 kHz) measurements capable of resolving transient flows with high temporal resolution. Therefore, high-frame rate measurements have enabled investigations on the evolution of the structure and dynamics of highly transient flows. These investigations play a critical role in understanding the fundamental physics of complex flows. A detailed description for performing high-resolution, high-speed planar PIV to study a transient flow near the surface of a flat plate is presented here. Details for adjusting the parameter constraints such as image and recording properties, the laser sheet properties, and processing algorithms to adapt PIV for any flow of interest are included. PMID:23851899

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Ronghui; Satkovich, John; Hu, Jianping

Peroxisomes are ubiquitous eukaryotic organelles that play pivotal roles in a suite of metabolic processes and often act coordinately with other organelles, such as chloroplasts and mitochondria. Peroxisomes import proteins to the peroxisome matrix by peroxins (PEX proteins), but how the function of the PEX proteins is regulated is poorly understood. In this study, we identified the Arabidopsis RING (really interesting new gene) type E3 ubiquitin ligase SP1 [suppressor of plastid protein import locus 1 (ppi1) 1] as a peroxisome membrane protein with a regulatory role in peroxisome protein import. SP1 interacts physically with the two components of the peroxisomemore » protein docking complex PEX13–PEX14 and the (RING)-finger peroxin PEX2. Loss of SP1 function suppresses defects of the pex14-2 and pex13-1 mutants, and SP1 is involved in the degradation of PEX13 and possibly PEX14 and all three RING peroxins. An in vivo ubiquitination assay showed that SP1 has the ability to promote PEX13 ubiquitination. Our study has revealed that, in addition to its previously reported function in chloroplast biogenesis, SP1 plays a role in peroxisome biogenesis. The same E3 ubiquitin ligase promotes the destabilization of components of two distinct protein-import machineries, indicating that degradation of organelle biogenesis factors by the ubiquitin–proteasome system may constitute an important regulatory mechanism in coordinating the biogenesis of metabolically linked organelles in eukaryotes.« less

Role of Fatty Acid Kinase in Cellular Lipid Homeostasis and SaeRS-Dependent Virulence Factor Expression in Staphylococcus aureus

PubMed Central

Ericson, Megan E.; Subramanian, Chitra; Frank, Matthew W.

2017-01-01

ABSTRACT The SaeRS two-component system is a master activator of virulence factor transcription in Staphylococcus aureus, but the cellular factors that control its activity are unknown. Fatty acid (FA) kinase is a two-component enzyme system required for extracellular FA uptake and SaeRS activity. Here, we demonstrate the existence of an intracellular nonesterified FA pool in S. aureus that is elevated in strains lacking FA kinase activity. SaeRS-mediated transcription is restored in FA kinase-negative strains when the intracellular FA pool is reduced either by growth with FA-depleted bovine serum albumin to extract the FA into the medium or by the heterologous expression of Neisseria gonorrhoeae acyl-acyl carrier protein synthetase to activate FA for phospholipid synthesis. These data show that FAs act as negative regulators of SaeRS signaling, and FA kinase activates SaeRS-dependent virulence factor production by lowering inhibitory FA levels. Thus, FA kinase plays a role in cellular lipid homeostasis by activating FA for incorporation into phospholipid, and it indirectly regulates SaeRS signaling by maintaining a low intracellular FA pool. PMID:28765222

Dynamical Generation of the Transition Zone in the Earth's Mantle

NASA Astrophysics Data System (ADS)

Hansen, U.; Stemmer, K.

2005-12-01

The internal structure of the Earth is made up by a series of layers, though it is unclear how many layers exist and if there are layers invisible to remote sensing techniques. The transition zone is likely to be a boundary layer separating the convective systems in the lower and upper mantle. It seems likely that currently there is some mass exchange across this boundary, rather than the two systems beeing strictly separated.a Double-diffusive convection(d.d.c) is a vital mechanism which can generate layered structure and may thus be an important mmical machinery behind the formation of the transition zone. Double-diffusive convection determines the dynamics of systems whose density is influenced by at least two components with different molecular diffusivities.In the mantle, composition and temperature play the role of those two components. By means of numerical experiments we demonstrate that under mantle relevant conditions d.d.c typically leads to the formation of a transition zone. The calculations encompass two- and three dimensional Cartesian geometries as well as fully 3D spherical domains. We have further included strongly temperature dependent viscosity and find that this leads to even more pronounced layering. In most cases a layered flow pattern emerges, where two layers with a transition zone in between resembles a quasistationary state. Thus, the transition zone can be the result of a self organization process of the convective flow in the mantle. The presence of a phase transition further helps to stabilize the boundary against overturning, even on a time scale on the order of the age of the Earth.

Effects of short-term active video game play on community adults: under International Classification of Functioning, Disability and Health consideration.

PubMed

Tseng, Wei-Che; Hsieh, Ru-Lan

2013-06-01

The effects of active video game play on healthy individuals remain uncertain. A person's functional health status constitutes a dynamic interaction between components identified in the International Classification of Functioning, Disability, and Health (ICF). The aim of this study was to investigate the short-term effects of active video game play on community adults using the ICF. Sixty community adults with an average age of 59.3 years and without physical disabilities were recruited. Over 2 weeks, each adult participated in six sessions of active video game play lasting 20 minutes each. Participants were assessed before and after the intervention. Variables were collected using sources related to the ICF components, including the Hospital Anxiety and Depression Scale, Multidimensional Fatigue Inventory, Biodex Stability System, chair- rising time, Frenchay Activity Index, Rivermead Mobility Index, Chronic Pain Grade Questionnaire, Work Ability Index, and World Health Organization Quality of Life-Brief Version. Compared to baseline data, significantly reduced risk of a fall measured by Biodex Stability System and improvements in disability scores measured by the Chronic Pain Grade Questionnaire were noted. There was no significant change in the other variables measured. Short-term, active video game play reduces fall risks and ameliorates disabilities in community adults.

Integrable multi-component generalization of a modified short pulse equation

NASA Astrophysics Data System (ADS)

Matsuno, Yoshimasa

2016-11-01

We propose a multi-component generalization of the modified short pulse (SP) equation which was derived recently as a reduction of Feng's two-component SP equation. Above all, we address the two-component system in depth. We obtain the Lax pair, an infinite number of conservation laws and multisoliton solutions for the system, demonstrating its integrability. Subsequently, we show that the two-component system exhibits cusp solitons and breathers for which the detailed analysis is performed. Specifically, we explore the interaction process of two cusp solitons and derive the formula for the phase shift. While cusp solitons are singular solutions, smooth breather solutions are shown to exist, provided that the parameters characterizing the solutions satisfy certain conditions. Last, we discuss the relation between the proposed system and existing two-component SP equations.

Already at the Table: Patterns of Play and Gambling Involvement Prior to Gambling Expansion.

PubMed

Nelson, Sarah E; LaPlante, Debi A; Gray, Heather M; Tom, Matthew A; Kleschinsky, John H; Shaffer, Howard J

2018-03-01

During 2011, the Governor of Massachusetts signed a bill to allow casino gambling in the state (Commonwealth of Massachusetts 2011). As a result, two resort casinos will begin operations during 2018 and 2019; a smaller slots parlor began operations during June 2015. Prior to this expansion, gambling was widely available in Massachusetts, through the state lottery, off-track betting, and gambling opportunities available in neighboring states. Within this context, it is important to understand the patterns of gambling involvement in the population prior to gambling expansion. The current study examined gambling involvement, patterns of play, and gambling-related problems prior to gambling expansion among a sample of 511 Massachusetts residents who were members of a statewide Internet panel. To measure patterns of play, we asked questions about past-year games played and frequency of play. To measure breadth of involvement, we assessed the number of different games played. To measure depth of involvement, we measured time spent gambling, amount wagered, and amount won or lost. Principal component analysis revealed four play pattern components accounting for more than 50% of the variance in game play frequency. Multiple regression analyses revealed that component scores composed of casino gambling and skill-based gambling (e.g., poker, sports) variables uniquely contributed to the prediction of gambling-related problems, even when depth of involvement was controlled. However, the addition of breadth of involvement to the model resulted in a model where no set of variables contributed significantly, suggesting a complex relationship among play patterns, depth, and breadth of involvement. The study established discrete and distinguishable gambling play patterns associated with gambling-related problems and identified groups of individuals potentially vulnerable to the effects of gambling expansion.

Turbomachine Interface Sealing

NASA Technical Reports Server (NTRS)

Hendricks, Robert C.; Chupp, Raymond E.; Lattime, Scott B.; Steinetz, Bruce M.

2005-01-01

Sealing interfaces and coatings, like lubricants, are sacrificial, giving up their integrity for the benefit of the component. Clearance control is a major issue in power systems turbomachine design and operational life. Sealing becomes the most cost-effective way to enhance system performance. Coatings, films, and combined use of both metals and ceramics play a major role in maintaining interface clearances in turbomachine sealing and component life. This paper focuses on conventional and innovative materials and design practices for sealing interfaces.

The Ethanol Project: Exploring Alternative Energy with Role-Play and Writing

ERIC Educational Resources Information Center

Winter, Julia

2013-01-01

This article describes a project that includes a two-week series of researching, essay writing, and speaking lessons exploring the broader implications of using ethanol as a fuel. The author, a chemistry teacher, describes how she uses a senate hearing discussion of ethanol fuel subsidies as the forum for a role-play. The four components of the…

An Investigation of the Effects of a Non-Sexist Curriculum on One Preschool Group's Sex-Role Stereotypical Behavior.

ERIC Educational Resources Information Center

Kroeger, Janice E.

This study investigated effects of a nonsexist curriculum on preschoolers' dramatic role play behavior and usage of language and play space. A quasi-experimental design included two preschool groups, one of which received a treatment component that consisted of a nonsexist curriculum. The treatment group included 12 males and 10 females between…

Utilization of Pb-free solders in MEMS packaging

NASA Astrophysics Data System (ADS)

Selvaduray, Guna S.

2003-01-01

Soldering of components within a package plays an important role in providing electrical interconnection, mechanical integrity and thermal dissipation. MEMS packages present challenges that are more complex than microelectronic packages because they are far more sensitive to shock and vibration and also require precision alignment. Soldering is used at two major levels within a MEMS package: at the die attach level and at the component attach level. Emerging environmental regulations worldwide, notably in Europe and Japan, have targeted the elimination of Pb usage in electronic assemblies, due to the inherent toxicity of Pb. This has provided the driving force for development and deployment of Pb-free solder alloys. A relatively large number of Pb-free solder alloys have been proposed by various researchers and companies. Some of these alloys have also been patented. After several years of research, the solder alloy system that has emerged is based on Sn as a major component. The electronics industry has identified different compositions for different specific uses, such as wave soldering, surface mount reflow, etc. The factors that affect choice of an appropriate Pb-free solder can be divided into two major categories, those related to manufacturing, and those related to long term reliability and performance.

Stability and Control of Human Trunk Movement During Walking.

PubMed

Wu, Q.; Sepehri, N.; Thornton-Trump, A. B.; Alexander, M.

1998-01-01

A mathematical model has been developed to study the control mechanisms of human trunk movement during walking. The trunk is modeled as a base-excited inverted pendulum with two-degrees of rotational freedom. The base point, corresponding to the bony landmark of the sacrum, can move in three-dimensional space in a general way. Since the stability of upright posture is essential for human walking, a controller has been designed such that the stability of the pendulum about the upright position is guaranteed. The control laws are developed based on Lyapunov's stability theory and include feedforward and linear feedback components. It is found that the feedforward component plays a critical role in keeping postural stability, and the linear feedback component, (resulting from viscoelastic function of the musculoskeletal system) can effectively duplicate the pattern of trunk movement. The mathematical model is validated by comparing the simulation results with those based on gait measurements performed in the Biomechanics Laboratory at the University of Manitoba.

Comparative Analysis of Wolbachia Genomes Reveals Streamlining and Divergence of Minimalist Two-Component Systems

PubMed Central

Christensen, Steen; Serbus, Laura Renee

2015-01-01

Two-component regulatory systems are commonly used by bacteria to coordinate intracellular responses with environmental cues. These systems are composed of functional protein pairs consisting of a sensor histidine kinase and cognate response regulator. In contrast to the well-studied Caulobacter crescentus system, which carries dozens of these pairs, the streamlined bacterial endosymbiont Wolbachia pipientis encodes only two pairs: CckA/CtrA and PleC/PleD. Here, we used bioinformatic tools to compare characterized two-component system relays from C. crescentus, the related Anaplasmataceae species Anaplasma phagocytophilum and Ehrlichia chaffeensis, and 12 sequenced Wolbachia strains. We found the core protein pairs and a subset of interacting partners to be highly conserved within Wolbachia and these other Anaplasmataceae. Genes involved in two-component signaling were positioned differently within the various Wolbachia genomes, whereas the local context of each gene was conserved. Unlike Anaplasma and Ehrlichia, Wolbachia two-component genes were more consistently found clustered with metabolic genes. The domain architecture and key functional residues standard for two-component system proteins were well-conserved in Wolbachia, although residues that specify cognate pairing diverged substantially from other Anaplasmataceae. These findings indicate that Wolbachia two-component signaling pairs share considerable functional overlap with other α-proteobacterial systems, whereas their divergence suggests the potential for regulatory differences and cross-talk. PMID:25809075

Characterization of vibration transfer paths in nose gearboxes of an AH-64 Apache

NASA Astrophysics Data System (ADS)

Islam, A. K. M. Anwarul; Dempsey, Paula J.; Feldman, Jason; Larsen, Chris

2014-03-01

Health monitoring of rotorcraft components, which is currently being performed by Health and Usage Monitoring Systems (HUMS) through analyzing vibration signatures of dynamic mechanical components, is very important for their safe and economic operation. Vibration diagnostic algorithms in HUMS analyze vibration signatures associated with faults and quantify them as condition indicators (CI) to predict component behavior. Vibration transfer paths (VTP) play important roles in CI response and are characterized by frequency response functions (FRF) derived from vibration signatures of dynamic mechanical components of a helicopter. With an objective to investigate the difference in VTP of a component in a helicopter and test stand, and to relate that to the CI response, VTP measurements were recorded from 0-50 kHz under similar conditions in the left and right nose gearboxes (NGBs) of an AH-64 Apache and an isolated left NGB in a test stand at NASA Glenn Research Center. The test fixture enabled the application of measured torques - common during an actual operation. Commercial and lab piezo shakers, and an impact hammer were used in both systems to collect the vibration response using two types of commercially available accelerometers under various test conditions. The FRFs of both systems were found to be consistent, and certain real-world installation and maintenance issues, such as sensor alignments, locations and installation torques, had minimal effect on the VTP. However, gear vibration transfer path dynamics appeared to be somewhat dependent on presence of oil, and the lightly-damped ring gear produced sharp and closer transfer path resonances.

Change Theory for Accounting System Reform in Health Sector: A Case Study of Kerman University of Medical Sciences in Iran

PubMed Central

Mehrolhassani, Mohammad Hossein; Emami, Mozhgan

2013-01-01

Background: Change theories provide an opportunity for organizational managers to plan, monitor and evaluate changes using a framework which enable them, among others, to show a fast response to environmental fluctuations and to predict the changing patterns of individuals and technology. The current study aimed to explore whether the change in the public accounting system of the Iranian health sector has followed Kurt Lewin’s change theory or not. Methods: This study which adopted a mixed methodology approach, qualitative and quantitative methods, was conducted in 2012. In the first phase of the study, 41 participants using purposive sampling and in the second phase, 32 affiliated units of Kerman University of Medical Sciences (KUMS) were selected as the study sample. Also, in phase one, we used face-to-face in-depth interviews (6 participants) and the quote method (35 participants) for data collection. We used a thematic framework analysis for analyzing data. In phase two, a questionnaire with a ten-point Likert scale was designed and then, data were analyzed using descriptive indicators, principal component and factorial analyses. Results: The results of phase one yielded a model consisting of four categories of superstructure, apparent infrastructure, hidden infrastructure and common factors. By linking all factors, totally, 12 components based on the quantitative results showed that the state of all components were not satisfactory at KUMS (5.06±2.16). Leadership and management; and technology components played the lowest and the greatest roles in implementing the accrual accounting system respectively. Conclusion: The results showed that the unfreezing stage did not occur well and the components were immature, mainly because the emphasis was placed on superstructure components rather than the components of hidden infrastructure. The study suggests that a road map should be developed in the financial system based on Kurt Lewin’s change theory and the model presented in this paper underpins the change management in any organizations. PMID:24596885

Change theory for accounting system reform in health sector: a case study of kerman university of medical sciences in iran.

PubMed

Mehrolhassani, Mohammad Hossein; Emami, Mozhgan

2013-11-01

Change theories provide an opportunity for organizational managers to plan, monitor and evaluate changes using a framework which enable them, among others, to show a fast response to environmental fluctuations and to predict the changing patterns of individuals and technology. The current study aimed to explore whether the change in the public accounting system of the Iranian health sector has followed Kurt Lewin's change theory or not. This study which adopted a mixed methodology approach, qualitative and quantitative methods, was conducted in 2012. In the first phase of the study, 41 participants using purposive sampling and in the second phase, 32 affiliated units of Kerman University of Medical Sciences (KUMS) were selected as the study sample. Also, in phase one, we used face-to-face in-depth interviews (6 participants) and the quote method (35 participants) for data collection. We used a thematic framework analysis for analyzing data. In phase two, a questionnaire with a ten-point Likert scale was designed and then, data were analyzed using descriptive indicators, principal component and factorial analyses. The results of phase one yielded a model consisting of four categories of superstructure, apparent infrastructure, hidden infrastructure and common factors. By linking all factors, totally, 12 components based on the quantitative results showed that the state of all components were not satisfactory at KUMS (5.06±2.16). Leadership and management; and technology components played the lowest and the greatest roles in implementing the accrual accounting system respectively. The results showed that the unfreezing stage did not occur well and the components were immature, mainly because the emphasis was placed on superstructure components rather than the components of hidden infrastructure. The study suggests that a road map should be developed in the financial system based on Kurt Lewin's change theory and the model presented in this paper underpins the change management in any organizations.

Methods of producing epoxides from alkenes using a two-component catalyst system

DOEpatents

Kung, Mayfair C.; Kung, Harold H.; Jiang, Jian

2013-07-09

Methods for the epoxidation of alkenes are provided. The methods include the steps of exposing the alkene to a two-component catalyst system in an aqueous solution in the presence of carbon monoxide and molecular oxygen under conditions in which the alkene is epoxidized. The two-component catalyst system comprises a first catalyst that generates peroxides or peroxy intermediates during oxidation of CO with molecular oxygen and a second catalyst that catalyzes the epoxidation of the alkene using the peroxides or peroxy intermediates. A catalyst system composed of particles of suspended gold and titanium silicalite is one example of a suitable two-component catalyst system.

Hard diffraction from quasi-elastic dipole scattering

NASA Astrophysics Data System (ADS)

Bialas, A.; Peschanski, R.

1996-02-01

The contribution to diffraction dissociation of virtual photons due to quasi-elastic scattering of the q- overlineq component is calculated in the framework of the QCD dipole picture. Both longitudinal and transverse components of the cross-section are given. It is shown that, at fixed mass of the diffractively produced system, quantum mechanical interference plays an important rôle. Phenomenological consequences are discussed.

Fixation of virgin lunar surface soil

NASA Technical Reports Server (NTRS)

Conley, J. M.; Frazer, R.; Cannon, W. A.

1972-01-01

Two systems are shown to be suitable for fixing loose particulate soils with a polymer film, without visually detectable disturbance of the soil particle spatial relationships. A two-component system is described, which uses a gas monomer condensible at the soil temperature and a gas phase catalyst acting to polymerize the monomer. A one-component system using a monomer which polymerizes spontaneously on and within the top few millimeters of the soil is also considered. The two-component system employs a simpler apparatus, but it operates over a narrower temperature range (approximately -40 to -10 C). Other two-component systems were identified which may operate at soil temperatures as high as +100 C, at relatively narrow temperature ranges of approximately 30 C. The one-component system was demonstrated to operate successfully with initial soil temperatures from -70 C or lower to +150 C.

The effector candidate repertoire of the arbuscular mycorrhizal fungus Rhizophagus clarus.

PubMed

Sędzielewska Toro, Kinga; Brachmann, Andreas

2016-02-09

Arbuscular mycorrhizal fungi (AMF) form an ecologically important symbiosis with more than two thirds of studied land plants. Recent studies of plant-pathogen interactions showed that effector proteins play a key role in host colonization by controlling the plant immune system. We hypothesise that also for symbiotic-plant interactions the secreted effectome of the fungus is a major component of communication and the conservation level of effector proteins between AMF species may be indicative whether they play a fundamental role. In this study, we used a bioinformatics pipeline to predict and compare the effector candidate repertoire of the two AMF species, Rhizophagus irregularis and Rhizophagus clarus. Our in silico pipeline revealed a list of 220 R. irregularis candidate effector genes that create a valuable information source to elucidate the mechanism of plant infection and colonization by fungi during AMF symbiotic interaction. While most of the candidate effectors show no homologies to known domains or proteins, the candidates with homologies point to potential roles in signal transduction, cell wall modification or transcription regulation. A remarkable aspect of our work is presence of a large portion of the effector proteins involved in symbiosis, which are not unique to each fungi or plant species, but shared along the Glomeromycota phylum. For 95% of R. irregularis candidates we found homologs in a R. clarus genome draft generated by Illumina high-throughput sequencing. Interestingly, 9% of the predicted effectors are at least as conserved between the two Rhizophagus species as proteins with housekeeping functions (similarity > 90%). Therefore, we state that this group of highly conserved effector proteins between AMF species may play a fundamental role during fungus-plant interaction. We hypothesise that in symbiotic interactions the secreted effectome of the fungus might be an important component of communication. Identification and functional characterization of the primary AMF effectors that regulate symbiotic development will help in understanding the mechanisms of fungus-plant interaction.

An Autonomous Autopilot Control System Design for Small-Scale UAVs

NASA Technical Reports Server (NTRS)

Ippolito, Corey; Pai, Ganeshmadhav J.; Denney, Ewen W.

2012-01-01

This paper describes the design and implementation of a fully autonomous and programmable autopilot system for small scale autonomous unmanned aerial vehicle (UAV) aircraft. This system was implemented in Reflection and has flown on the Exploration Aerial Vehicle (EAV) platform at NASA Ames Research Center, currently only as a safety backup for an experimental autopilot. The EAV and ground station are built on a component-based architecture called the Reflection Architecture. The Reflection Architecture is a prototype for a real-time embedded plug-and-play avionics system architecture which provides a transport layer for real-time communications between hardware and software components, allowing each component to focus solely on its implementation. The autopilot module described here, although developed in Reflection, contains no design elements dependent on this architecture.

Tutorial on Quantification of Differences between Single- and Two-Component Two-Phase Flow and Heat Transfer

NASA Astrophysics Data System (ADS)

Delil, A. A. M.

2003-01-01

Single-component two-phase systems are envisaged for aerospace thermal control applications: Mechanically Pumped Loops, Vapour Pressure Driven Loops, Capillary Pumped Loops and Loop Heat Pipes. Thermal control applications are foreseen in different gravity environments: Micro-g, reduced-g for Mars or Moon bases, 1-g during terrestrial testing, and hyper-g in rotating spacecraft, during combat aircraft manoeuvres and in systems for outer planets. In the evaporator, adiabatic line and condenser sections of such single-component two-phase systems, the fluid is a mixture of the working liquid (for example ammonia, carbon dioxide, ethanol, or other refrigerants, etc.) and its saturated vapour. Results of two-phase two-component flow and heat transfer research (pertaining to liquid-gas mixtures, e.g. water/air, or argon or helium) are often applied to support research on flow and heat transfer in two-phase single-component systems. The first part of the tutorial updates the contents of two earlier tutorials, discussing various aerospace-related two-phase flow and heat transfer research. It deals with the different pressure gradient constituents of the total pressure gradient, with flow regime mapping (including evaporating and condensing flow trajectories in the flow pattern maps), with adiabatic flow and flashing, and with thermal-gravitational scaling issues. The remaining part of the tutorial qualitatively and quantitatively determines the differences between single- and two-component systems: Two systems that physically look similar and close, but in essence are fully different. It was already elucidated earlier that, though there is a certain degree of commonality, the differences will be anything but negligible, in many cases. These differences (quantified by some examples) illustrates how careful one shall be in interpreting data resulting from two-phase two-component simulations or experiments, for the development of single-component two-phase thermal control systems for various gravity environments.

The Treatment of Cancer through Hypnosis.

ERIC Educational Resources Information Center

Goldberg, Bruce

1985-01-01

This report traces the immunological components of the cancer process and illustrates how vital a role is played by stress. The work of the Simontons is used to discuss the relationship between stress, the immune system and cancer. Hypnotic visualization techniques and their effects on the immune system are also reviewed. (Author)

Vitamins E and C - effects on matrix components in the vascular system

USDA-ARS?s Scientific Manuscript database

The connective tissue in the vascular system, consisting mainly of vascular smooth muscle cells (VSMC) and the interstitial extracellular matrix (ECM), plays important roles in the maintenance of an intact vascular wall as well as in the repair of atherosclerotic lesions during disease development. ...

ξTauri: a unique laboratory to study the dynamic interaction in a compact hierarchical quadruple system

NASA Astrophysics Data System (ADS)

Nemravová, J. A.; Harmanec, P.; Brož, M.; Vokrouhlický, D.; Mourard, D.; Hummel, C. A.; Cameron, C.; Matthews, J. M.; Bolton, C. T.; Božić, H.; Chini, R.; Dembsky, T.; Engle, S.; Farrington, C.; Grunhut, J. H.; Guenther, D. B.; Guinan, E. F.; Korčáková, D.; Koubský, P.; Kříček, R.; Kuschnig, R.; Mayer, P.; McCook, G. P.; Moffat, A. F. J.; Nardetto, N.; Prša, A.; Ribeiro, J.; Rowe, J.; Rucinski, S.; Škoda, P.; Šlechta, M.; Tallon-Bosc, I.; Votruba, V.; Weiss, W. W.; Wolf, M.; Zasche, P.; Zavala, R. T.

2016-10-01

Context. Compact hierarchical systems are important because the effects caused by the dynamical interaction among its members occur ona human timescale. These interactions play a role in the formation of close binaries through Kozai cycles with tides. One such system is ξ Tauri: it has three hierarchical orbits: 7.14 d (eclipsing components Aa, Ab), 145 d (components Aa+Ab, B), and 51 yr (components Aa+Ab+B, C). Aims: We aim to obtain physical properties of the system and to study the dynamical interaction between its components. Methods: Our analysis is based on a large series of spectroscopic photometric (including space-borne) observations and long-baseline optical and infrared spectro-interferometric observations. We used two approaches to infer the system properties: a set of observation-specific models, where all components have elliptical trajectories, and an N-body model, which computes the trajectory of each component by integrating Newton's equations of motion. Results: The triple subsystem exhibits clear signs of dynamical interaction. The most pronounced are the advance of the apsidal line and eclipse-timing variations. We determined the geometry of all three orbits using both observation-specific and N-body models. The latter correctly accounted for observed effects of the dynamical interaction, predicted cyclic variations of orbital inclinations, and determined the sense of motion of all orbits. Using perturbation theory, we demonstrate that prominent secular and periodic dynamical effects are explainable with a quadrupole interaction. We constrained the basic properties of all components, especially of members of the inner triple subsystem and detected rapid low-amplitude light variations that we attribute to co-rotating surface structures of component B. We also estimated the radius of component B. Properties of component C remain uncertain because of its low relative luminosity. We provide an independent estimate of the distance to the system. Conclusions: The accuracy and consistency of our results make ξ Tau an excellent test bed for models of formation and evolution of hierarchical systems. Full Tables D.1-D.7 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/594/A55Based on data from the MOST satellite, a former Canadian Space Agency mission, jointly operated by Microsatellite Systems Canada Inc. (MSCI; formerly Dynacon Inc.), the University of Toronto Institute for Aerospace Studies and the University of British Columbia, with the assistance of the University of Vienna.

A Multi-mission Event-Driven Component-Based System for Support of Flight Software Development, ATLO, and Operations first used by the Mars Science Laboratory (MSL) Project

NASA Technical Reports Server (NTRS)

Dehghani, Navid; Tankenson, Michael

2006-01-01

This viewgraph presentation reviews the architectural description of the Mission Data Processing and Control System (MPCS). MPCS is an event-driven, multi-mission ground data processing components providing uplink, downlink, and data management capabilities which will support the Mars Science Laboratory (MSL) project as its first target mission. MPCS is designed with these factors (1) Enabling plug and play architecture (2) MPCS has strong inheritance from GDS components that have been developed for other Flight Projects (MER, MRO, DAWN, MSAP), and are currently being used in operations and ATLO, and (3) MPCS components are Java-based, platform independent, and are designed to consume and produce XML-formatted data

Definition of Contravariant Velocity Components

NASA Technical Reports Server (NTRS)

Hung, Ching-Mao; Kwak, Dochan (Technical Monitor)

2002-01-01

This is an old issue in computational fluid dynamics (CFD). What is the so-called contravariant velocity or contravariant velocity component? In the article, we review the basics of tensor analysis and give the contravariant velocity component a rigorous explanation. For a given coordinate system, there exist two uniquely determined sets of base vector systems - one is the covariant and another is the contravariant base vector system. The two base vector systems are reciprocal. The so-called contravariant velocity component is really the contravariant component of a velocity vector for a time-independent coordinate system, or the contravariant component of a relative velocity between fluid and coordinates, for a time-dependent coordinate system. The contravariant velocity components are not physical quantities of the velocity vector. Their magnitudes, dimensions, and associated directions are controlled by their corresponding covariant base vectors. Several 2-D (two-dimensional) linear examples and 2-D mass-conservation equation are used to illustrate the details of expressing a vector with respect to the covariant and contravariant base vector systems, respectively.

Nonlinear Dynamics of Multi-Component Bose-Einstein Condensates ---Anti-Gravity Transport and Vortex Chaos---

NASA Astrophysics Data System (ADS)

Nakamura, K.

Bose-Einstein condensate(BEC) provides a nice stage when the nonlinearSchrödinger equation plays a vital role. We study the dynamics of multi-component repulsive BEC in 2 dimensions with harmonic traps by using the nonlinear Schrödinger (or Gross-Pitaevskii) equation. Firstly we consider a driven two-component BEC with each component trapped in different vertical positions. The appropriate tuning of the oscillation frequency of the magnetic field leads to a striking anti-gravity transport of BEC. This phenomenon is a manifestation of macroscopic non-adiabatic tunneling in a system with two internal(electronic) degrees of freedom. The dynamics splits into a fast complex spatio-temporal oscillation of each condensate wavefunctions together with a slow levitation of the total center of mass. Secondly, we examine the three-component repulsive BEC in 2 dimensions in a harmonic trap in the absence of magnetic field, and construct a model of conservative chaos based on a picture of vortex molecules. We obtain an effective nonlinear dynamics for three vortex cores, which represents three charged particles under the uniform magnetic field with the repulsive inter-particle potential quadratic in the inter-vortex distance r_{ij} on short scale and logarithmic in r_{ij} on large scale. The vortices here acquire the inertia in marked contrast to the standard theory of point vortices since Onsager. We then explore ``the chaos in the three-body problem" in the context of vortices with inertia.

Developmental Exposure to Low Levels of Ethinylestradiol Affects Play Behavior in Juvenile Female Rats.

PubMed

Zaccaroni, Marco; Massolo, Alessandro; Della Seta, Daniele; Farabollini, Francesca; Giannelli, Giulietta; Fusani, Leonida; Dessì-Fulgheri, Francesco

2018-05-01

Juvenile social play contributes to the development of adult social and emotional skills in humans and non-human animals, and is therefore a useful endpoint to study the effects of endocrine disrupters on behavior in animal models. Ethinylestradiol (EE 2 ) is a widely produced, powerful synthetic estrogen that is widespread in the environment mainly because is a component of the contraceptive pill. In addition, fetuses may be exposed to EE2 when pregnancy is undetected during contraceptive treatment. To understand whether exposure to EE 2 during gestation or lactation affects social play, we exposed 72 female Sprague-Dawley rats to EE 2 or vehicle either during gestation (gestation day (GD) 5 through GD 20) or during lactation (from postnatal day (PND) 1 through PND 21). Two doses of EE 2 were used to treat the dams: a lower dose in the range of possible environmental exposure (4 ng/kg/day) and a higher dose equivalent to that received during contraceptive treatment (400 ng/kg/day). Behavioral testing was carried out between PND 40 and 45. A principal component analysis of frequencies of behavioral items observed during play sessions identified three main components: defensive-like play, aggressive-like play, and exploration. Aggressive-like play was significantly increased by both doses of EE 2 , and the gestational administration was in general more effective than the lactational one. Defensive-like play and exploration were not significantly affected by treatment. This research showed that low and very low doses of EE 2 that mimic clinical or environmental exposure during development can affect important aspects of social behavior even during restricted time windows.

Verification and Validation of KBS with Neural Network Components

NASA Technical Reports Server (NTRS)

Wen, Wu; Callahan, John

1996-01-01

Artificial Neural Network (ANN) play an important role in developing robust Knowledge Based Systems (KBS). The ANN based components used in these systems learn to give appropriate predictions through training with correct input-output data patterns. Unlike traditional KBS that depends on a rule database and a production engine, the ANN based system mimics the decisions of an expert without specifically formulating the if-than type of rules. In fact, the ANNs demonstrate their superiority when such if-then type of rules are hard to generate by human expert. Verification of traditional knowledge based system is based on the proof of consistency and completeness of the rule knowledge base and correctness of the production engine.These techniques, however, can not be directly applied to ANN based components.In this position paper, we propose a verification and validation procedure for KBS with ANN based components. The essence of the procedure is to obtain an accurate system specification through incremental modification of the specifications using an ANN rule extraction algorithm.

Modular and coordinated expression of immune system regulatory and signaling components in the developing and adult nervous system.

PubMed

Monzón-Sandoval, Jimena; Castillo-Morales, Atahualpa; Crampton, Sean; McKelvey, Laura; Nolan, Aoife; O'Keeffe, Gerard; Gutierrez, Humberto

2015-01-01

During development, the nervous system (NS) is assembled and sculpted through a concerted series of neurodevelopmental events orchestrated by a complex genetic programme. While neural-specific gene expression plays a critical part in this process, in recent years, a number of immune-related signaling and regulatory components have also been shown to play key physiological roles in the developing and adult NS. While the involvement of individual immune-related signaling components in neural functions may reflect their ubiquitous character, it may also reflect a much wider, as yet undescribed, genetic network of immune-related molecules acting as an intrinsic component of the neural-specific regulatory machinery that ultimately shapes the NS. In order to gain insights into the scale and wider functional organization of immune-related genetic networks in the NS, we examined the large scale pattern of expression of these genes in the brain. Our results show a highly significant correlated expression and transcriptional clustering among immune-related genes in the developing and adult brain, and this correlation was the highest in the brain when compared to muscle, liver, kidney and endothelial cells. We experimentally tested the regulatory clustering of immune system (IS) genes by using microarray expression profiling in cultures of dissociated neurons stimulated with the pro-inflammatory cytokine TNF-alpha, and found a highly significant enrichment of immune system-related genes among the resulting differentially expressed genes. Our findings strongly suggest a coherent recruitment of entire immune-related genetic regulatory modules by the neural-specific genetic programme that shapes the NS.

Excitation-resolved cone-beam x-ray luminescence tomography.

PubMed

Liu, Xin; Liao, Qimei; Wang, Hongkai; Yan, Zhuangzhi

2015-07-01

Cone-beam x-ray luminescence computed tomography (CB-XLCT), as an emerging imaging technique, plays an important role in in vivo small animal imaging studies. However, CB-XLCT suffers from low-spatial resolution due to the ill-posed nature of reconstruction. We improve the imaging performance of CB-XLCT by using a multiband excitation-resolved imaging scheme combined with principal component analysis. To evaluate the performance of the proposed method, the physical phantom experiment is performed with a custom-made XLCT/XCT imaging system. The experimental results validate the feasibility of the method, where two adjacent nanophosphors (with an edge-to-edge distance of 2.4 mm) can be located.

Exact Boson-Fermion Duality on a 3D Euclidean Lattice

DOE PAGES

Chen, Jing-Yuan; Son, Jun Ho; Wang, Chao; ...

2018-01-05

The idea of statistical transmutation plays a crucial role in descriptions of the fractional quantum Hall effect. However, a recently conjectured duality between a critical boson and a massless two-component Dirac fermion extends this notion to gapless systems. This duality sheds light on highly nontrivial problems such as the half-filled Landau level, the superconductor-insulator transition, and surface states of strongly coupled topological insulators. Although this boson-fermion duality has undergone many consistency checks, it has remained unproven. Here, we describe the duality in a nonperturbative fashion using an exact UV mapping of partition functions on a 3D Euclidean lattice.

Exact Boson-Fermion Duality on a 3D Euclidean Lattice.

PubMed

Chen, Jing-Yuan; Son, Jun Ho; Wang, Chao; Raghu, S

2018-01-05

The idea of statistical transmutation plays a crucial role in descriptions of the fractional quantum Hall effect. However, a recently conjectured duality between a critical boson and a massless two-component Dirac fermion extends this notion to gapless systems. This duality sheds light on highly nontrivial problems such as the half-filled Landau level, the superconductor-insulator transition, and surface states of strongly coupled topological insulators. Although this boson-fermion duality has undergone many consistency checks, it has remained unproven. We describe the duality in a nonperturbative fashion using an exact UV mapping of partition functions on a 3D Euclidean lattice.

Exact Boson-Fermion Duality on a 3D Euclidean Lattice

NASA Astrophysics Data System (ADS)

Chen, Jing-Yuan; Son, Jun Ho; Wang, Chao; Raghu, S.

2018-01-01

The idea of statistical transmutation plays a crucial role in descriptions of the fractional quantum Hall effect. However, a recently conjectured duality between a critical boson and a massless two-component Dirac fermion extends this notion to gapless systems. This duality sheds light on highly nontrivial problems such as the half-filled Landau level, the superconductor-insulator transition, and surface states of strongly coupled topological insulators. Although this boson-fermion duality has undergone many consistency checks, it has remained unproven. We describe the duality in a nonperturbative fashion using an exact UV mapping of partition functions on a 3D Euclidean lattice.

Modeling and investigation of refrigeration system performance with two-phase fluid injection in a scroll compressor

NASA Astrophysics Data System (ADS)

Gu, Rui

Vapor compression cycles are widely used in heating, refrigerating and air-conditioning. A slight performance improvement in the components of a vapor compression cycle, such as the compressor, can play a significant role in saving energy use. However, the complexity and cost of these improvements can block their application in the market. Modifying the conventional cycle configuration can offer a less complex and less costly alternative approach. Economizing is a common modification for improving the performance of the refrigeration cycle, resulting in decreasing the work required to compress the gas per unit mass. Traditionally, economizing requires multi-stage compressors, the cost of which has restrained the scope for practical implementation. Compressors with injection ports, which can be used to inject economized refrigerant during the compression process, introduce new possibilities for economization with less cost. This work focuses on computationally investigating a refrigeration system performance with two-phase fluid injection, developing a better understanding of the impact of injected refrigerant quality on refrigeration system performance as well as evaluating the potential COP improvement that injection provides based on refrigeration system performance provided by Copeland.

Software Architecture Evolution

DTIC Science & Technology

2013-12-01

system’s major components occurring via a Java Message Service message bus [69]. This architecture was designed to promote loose coupling of soft- ware...play reconfiguration of the system. The components were Java -based and platform-independent; the interfaces by which they communicated were based on...The MPCS database, a MySQL database used for storing telemetry as well as some other information, such as logs and commanding data [68]. This

E3 ubiquitin ligase SP1 regulates peroxisome biogenesis in Arabidopsis

DOE PAGES

Pan, Ronghui; Satkovich, John; Hu, Jianping

2016-10-31

Peroxisomes are ubiquitous eukaryotic organelles that play pivotal roles in a suite of metabolic processes and often act coordinately with other organelles, such as chloroplasts and mitochondria. Peroxisomes import proteins to the peroxisome matrix by peroxins (PEX proteins), but how the function of the PEX proteins is regulated is poorly understood. In this study, we identified the Arabidopsis RING (really interesting new gene) type E3 ubiquitin ligase SP1 [suppressor of plastid protein import locus 1 (ppi1) 1] as a peroxisome membrane protein with a regulatory role in peroxisome protein import. SP1 interacts physically with the two components of the peroxisomemore » protein docking complex PEX13–PEX14 and the (RING)-finger peroxin PEX2. Loss of SP1 function suppresses defects of the pex14-2 and pex13-1 mutants, and SP1 is involved in the degradation of PEX13 and possibly PEX14 and all three RING peroxins. An in vivo ubiquitination assay showed that SP1 has the ability to promote PEX13 ubiquitination. Our study has revealed that, in addition to its previously reported function in chloroplast biogenesis, SP1 plays a role in peroxisome biogenesis. The same E3 ubiquitin ligase promotes the destabilization of components of two distinct protein-import machineries, indicating that degradation of organelle biogenesis factors by the ubiquitin–proteasome system may constitute an important regulatory mechanism in coordinating the biogenesis of metabolically linked organelles in eukaryotes.« less

An indirect component in the evoked compound action potential of the vagal nerve.

PubMed

Ordelman, Simone C M A; Kornet, Lilian; Cornelussen, Richard; Buschman, Hendrik P J; Veltink, Peter H

2010-12-01

The vagal nerve plays a vital role in the regulation of the cardiovascular system. It not only regulates the heart but also sends sensory information from the heart back to the brain. We hypothesize that the evoked vagal nerve compound action potential contains components that are indirect via the brain stem or coming via the neural network on the heart. In an experimental study of 15 pigs, we identified four components in the evoked compound action potentials. The fourth component was found to be an indirect component, which came from the periphery. The latency of the indirect component increased when heart rate and contractility were decreased by burst stimulation (P = 0.01; n = 7). When heart rate and contractility were increased by dobutamine administration, the latency of the indirect component decreased (P = 0.01; n = 9). This showed that the latency of the indirect component of the evoked compound action potentials may relate to the state of the cardiovascular system.

[The endogenous opioid system and drug addiction].

PubMed

Maldonado, R

2010-01-01

Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits. Several neurotransmitters, including the endogenous opioid system are involved in these changes. The opioid system plays a pivotal role in different aspects of addiction. Thus, opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within the reward circuits. Opioid receptors and peptides are selectively involved in several components of the addictive processes induced by opioids, cannabinoids, psychostimulants, alcohol and nicotine. This review is focused on the contribution of each component of the endogenous opioid system in the addictive properties of the different drugs of abuse. Copyright 2010 Elsevier Masson SAS. All rights reserved.

Plug and Play PV Systems for American Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoepfner, Christian

2016-12-22

The core objectives of the Plug & Play PV Systems Project were to develop a PV system that can be installed on a residential rooftop for less than $1.50/W in 2020, and in less than 10 hours (from point of purchase to commissioning). The Fraunhofer CSE team’s approach to this challenge involved a holistic approach to system design – hardware and software – that make Plug & Play PV systems: • Quick, easy, and safe to install • Easy to demonstrate as code compliant • Permitted, inspected, and interconnected via an electronic process Throughout the three years of work duringmore » this Department of Energy SunShot funded project, the team engaged in a substantive way with inspectional services departments and utilities, manufacturers, installers, and distributors. We received iterative feedback on the system design and on ideas for how such systems can be commercialized. This ultimately led us to conceiving of Plug & Play PV Systems as a framework, with a variety of components compatible with the Plug & Play PV approach, including string or microinverters, conventional modules or emerging lightweight modules. The framework enables a broad group of manufacturers to participate in taking Plug & Play PV Systems to market, and increases the market size for such systems. Key aspects of the development effort centered on the system hardware and associated engineering work, the development of a Plug & Play PV Server to enable the electronic permitting, inspection and interconnection process, understanding the details of code compliance and, on occasion, supporting applications for modifications to the code to allow lightweight modules, for example. We have published a number of papers on our testing and assessment of novel technologies (e.g., adhered lightweight modules) and on the electronic architecture.« less

The role of management in an in vitro fertilization practice.

PubMed

Masler, Steve; Strickland, Robert R

2013-05-01

An in vitro fertilization (IVF) practice is an enterprise. Like any enterprise, it has management that plays a major role, forming the structure, framework, and components that make the practice viable. Management of an IVF practice consists of two key teams: the fertility team and the management team. Management activities of the teams fall into eight core areas: business operations, financial, human resources, information technology, organizational governance, risk management, patient care systems, and quality management. Shady Grove Fertility Centers and Huntington Reproductive Center are two examples of professionally managed large fertility practices, one managed mostly centrally and the other largely managed in a decentralized way. Management is what takes a physician's IVF practice and converts it to a professional enterprise. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Exploration of cellular reaction systems.

PubMed

Kirkilionis, Markus

2010-01-01

We discuss and review different ways to map cellular components and their temporal interaction with other such components to different non-spatially explicit mathematical models. The essential choices made in the literature are between discrete and continuous state spaces, between rule and event-based state updates and between deterministic and stochastic series of such updates. The temporal modelling of cellular regulatory networks (dynamic network theory) is compared with static network approaches in two first introductory sections on general network modelling. We concentrate next on deterministic rate-based dynamic regulatory networks and their derivation. In the derivation, we include methods from multiscale analysis and also look at structured large particles, here called macromolecular machines. It is clear that mass-action systems and their derivatives, i.e. networks based on enzyme kinetics, play the most dominant role in the literature. The tools to analyse cellular reaction networks are without doubt most complete for mass-action systems. We devote a long section at the end of the review to make a comprehensive review of related tools and mathematical methods. The emphasis is to show how cellular reaction networks can be analysed with the help of different associated graphs and the dissection into modules, i.e. sub-networks.

Towards an Innovative Web-Based Lab Delivery System for a Management Information Systems Course

ERIC Educational Resources Information Center

Breimer, Eric; Cotler, Jami; Yoder, Robert

2011-01-01

While online systems are an essential component of distance learning, they can also play a critical role in improving the delivery of activities in a traditional laboratory setting. The quality and effectiveness of online course delivery is often compared to equivalent face-to-face alternatives. In our approach, we have harnessed what we feel to…

Production of a novel antioxidant furan fatty acid from 7,10-dihydroxy-8(E)-octadecenoic acid

USDA-ARS?s Scientific Manuscript database

Furan fatty acids (F-acids) have gained attention since they are known to play important roles in a variety of biological systems. Specifically F-acids are known to have strong antioxidant activity. Although widely distributed in most biological systems, F-acids are trace components and their biosyn...

Diet Modifies the Neuroimmune System by Influencing Macrophage Activation

ERIC Educational Resources Information Center

Sherry, Christina Lynn

2009-01-01

It has long been appreciated that adequate nutrition is required for proper immune function and it is now recognized that dietary components contribute to modulation of immune cells, subsequently impacting the whole body's response during an immune challenge. Macrophage activation plays a critical role in the immune system and directs the…

Space Shuttle Projects

NASA Image and Video Library

2001-01-01

The Space Shuttle represented an entirely new generation of space vehicles, the world's first reusable spacecraft. Unlike earlier expendable rockets, the Shuttle was designed to be launched over and over again and would serve as a system for ferrying payloads and persornel to and from Earth orbit. The Shuttle's major components are the orbiter spacecraft; the three main engines, with a combined thrust of more than 1.2 million pounds; the huge external tank (ET) that feeds the liquid hydrogen fuel and liquid oxygen oxidizer to the three main engines; and the two solid rocket boosters (SRB's), with their combined thrust of some 5.8 million pounds, that provide most of the power for the first two minutes of flight. Crucially involved with the Space Shuttle program virtually from its inception, the Marshall Space Flight Center (MSFC) played a leading role in the design, development, testing, and fabrication of many major Shuttle propulsion components. The MSFC was assigned responsibility for developing the Shuttle orbiter's high-performance main engines, the most complex rocket engines ever built. The MSFC was also responsible for developing the Shuttle's massive ET and the solid rocket motors and boosters.

Space Shuttle Projects

NASA Image and Video Library

1975-01-01

The Space Shuttle represented an entirely new generation of space vehicle, the world's first reusable spacecraft. Unlike earlier expendable rockets, the Shuttle was designed to be launched over and over again and would serve as a system for ferrying payloads and persornel to and from Earth orbit. The Shuttle's major components are the orbiter spacecraft; the three main engines, with a combined thrust of more than 1.2 million pounds; the huge external tank (ET) that feeds the liquid hydrogen fuel and liquid oxygen oxidizer to the three main engines; and the two solid rocket boosters (SRB's), with their combined thrust of some 5.8 million pounds. The SRB's provide most of the power for the first two minutes of flight. Crucially involved with the Space Shuttle program virtually from its inception, the Marshall Space Flight Center (MSFC) played a leading role in the design, development, testing, and fabrication of many major Shuttle propulsion components. The MSFC was assigned responsibility for developing the Shuttle orbiter's high-performance main engines, the most complex rocket engines ever built. The MSFC was also responsible for developing the Shuttle's massive ET and the solid rocket motors and boosters.

Simultaneous multi-component seismic denoising and reconstruction via K-SVD

NASA Astrophysics Data System (ADS)

Hou, Sian; Zhang, Feng; Li, Xiangyang; Zhao, Qiang; Dai, Hengchang

2018-06-01

Data denoising and reconstruction play an increasingly significant role in seismic prospecting for their value in enhancing effective signals, dealing with surface obstacles and reducing acquisition costs. In this paper, we propose a novel method to denoise and reconstruct multicomponent seismic data simultaneously. This method lies within the framework of machine learning and the key points are defining a suitable weight function and a modified inner product operator. The purpose of these two processes are to perform missing data machine learning when the random noise deviation is unknown, and building a mathematical relationship for each component to incorporate all the information of multi-component data. Two examples, using synthetic and real multicomponent data, demonstrate that the new method is a feasible alternative for multi-component seismic data processing.

Both IIC and IID Components of Mannose Phosphotransferase System Are Involved in the Specific Recognition between Immunity Protein PedB and Bacteriocin-Receptor Complex.

PubMed

Zhou, Wanli; Wang, Guohong; Wang, Chunmei; Ren, Fazheng; Hao, Yanling

2016-01-01

Upon exposure to exogenous pediocin-like bacteriocins, immunity proteins specifically bind to the target receptor of the mannose phosphotransferase system components (man-PTS IIC and IID), therefore preventing bacterial cell death. However, the specific recognition of immunity proteins and its associated target receptors remains poorly understood. In this study, we constructed hybrid receptors to identify the domains of IIC and/or IID recognized by the immunity protein PedB, which confers immunity to pediocin PA-1. Using Lactobacillus plantarum man-PTS EII mutant W903, the IICD components of four pediocin PA-1-sensitive strains (L. plantarum WQ0815, Leuconostoc mesenteroides 05-43, Lactobacillus salivarius REN and Lactobacillus acidophilus 05-172) were respectively co-expressed with the immunity protein PedB. Well-diffusions assays showed that only the complex formed by LpIICD from L. plantarum WQ0815 with pediocin PA-1 could be recognized by PedB. In addition, a two-step PCR approach was used to construct hybrid receptors by combining LpIIC or LpIID recognized by PedB with the other three heterologous IID or IIC compounds unrecognized by PedB, respectively. The results showed that all six hybrid receptors were recognized by pediocin PA-1. However, when IIC or IID of L. plantarum WQ0815 was replaced with any corresponding IIC or IID component from L. mesenteroides 05-43, L. salivarius REN and L. acidophilus 05-172, all the hybrid receptors could not be recognized by PedB. Taken altogether, we concluded that both IIC and IID components of the mannose phosphotransferase system play an important role in the specific recognition between the bacteriocin-receptor complex and the immunity protein PedB.

Relativistic equation-of-motion coupled-cluster method using open-shell reference wavefunction: Application to ionization potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pathak, Himadri, E-mail: hmdrpthk@gmail.com; Sasmal, Sudip, E-mail: sudipsasmal.chem@gmail.com; Vaval, Nayana

2016-08-21

The open-shell reference relativistic equation-of-motion coupled-cluster method within its four-component description is successfully implemented with the consideration of single- and double- excitation approximations using the Dirac-Coulomb Hamiltonian. At the first attempt, the implemented method is employed to calculate ionization potential value of heavy atomic (Ag, Cs, Au, Fr, and Lr) and molecular (HgH and PbF) systems, where the effect of relativity does really matter to obtain highly accurate results. Not only the relativistic effect but also the effect of electron correlation is crucial in these heavy atomic and molecular systems. To justify the fact, we have taken two further approximationsmore » in the four-component relativistic equation-of-motion framework to quantify how the effect of electron correlation plays a role in the calculated values at different levels of theory. All these calculated results are compared with the available experimental data as well as with other theoretically calculated values to judge the extent of accuracy obtained in our calculations.« less

Collectivity and manifestations of minimum-bias jets in high-energy nuclear collisions

NASA Astrophysics Data System (ADS)

Trainor, Thomas A.

2018-01-01

Collectivity, as interpreted to mean flow of a dense medium in high-energy A-A collisions described by hydrodynamics, has been attributed to smaller collision systems - p-A and even p-p collisions - based on recent analysis of LHC data. However, alternative methods reveal that some data features attributed to flows are actually manifestations of minimum-bias (MB) jets. In this presentation I review the differential structure of single-particle pt spectra from SPS to LHC energies in the context of a two-component (soft + hard) model (TCM) of hadron production. I relate the spectrum hard component to measured properties of isolated jets. I use the spectrum TCM to predict accurately the systematics of ensemble-mean p̅t in p-p, p-A and A-A collision systems over a large energy interval. Detailed comparisons of the TCM with spectrum and correlation data suggest that MB jets play a dominant role in hadron production near midrapidity. Claimed flow phenomena are better explained as jet manifestations agreeing quantitatively with measured jet properties.

Status and Plans for Reanalysis at NASA/GMAO

NASA Technical Reports Server (NTRS)

Gelaro, Ron

2017-01-01

Reanalysis plays a critical role in GMAOs goal to enhance NASA's program of Earth observations, providing vital data sets for climate research and the development of future missions. As the breadth of NASAs observations expands to include multiple components of the Earth system, so does the need to assimilate observations from currently uncoupled components of the system in a more physically consistent manner. GMAOs most recent reanalysis of the satellite era, MERRA-2, has completed the period 1980-present, and is now running as a continuing global climate analysis with two- to three-week latency. MERRA-2 assimilates meteorological and aerosol observations as a weakly coupled assimilation system as a first step toward GMAOs longer term goal of developing an integrated Earth system analysis (IESA) capability that will couple assimilation systems for the atmosphere, ocean, land and chemistry. The GMAO strategy is to progress incrementally toward an IESA through an evolving combination of coupled systems and offline component reanalyses driven by, for example, MERRA-2 atmospheric forcing. Most recently, the GMAO has implemented a weakly coupled assimilation scheme for analyzing ocean skin temperature within the existing atmospheric analysis. The scheme uses background fields from a near-surface ocean diurnal layer model to assimilate surface-sensitive radiances plus in-situ observations along with all other observations in the atmospheric assimilation system. In addition, MERRA-2-driven simulations of the ocean (plus sea ice) and atmospheric chemistry (for the EOS period) are currently underway, as is the development of a coupled atmosphere-ocean assimilation system. This talk will describe the status of these ongoing efforts and the planned steps toward an IESA capability for climate research.

Results of availability imposed configuration details developed for K-DEMO

DOE PAGES

Brown, Tom; Titus, Peter; Brooks, Art; ...

2016-02-05

We completed a two year study using the Korean fusion demonstration reactor (K-DEMO) where we looked at key Tokamak components and configuration options in preparation of a conceptual design phase. A key part of a device configuration centers on defining an arrangement that enhances the ability to reach high availability values by defining design solutions that foster simplified maintenance operations. In order to maximize the size and minimize the number of in-vessel components enlarged TF coils were defined that incorporate a pair of windings within each coil to mitigate pressure drop issues and to reduce the cost of the coils.more » Furthermore, we defined a semi-permanent shield structure in order to develop labyrinth interfaces between double-null plasma contoured shield modules, provide an entity to align blanket components and provide support against disruption loads—with a load path that equilibrates blanket, TF and PF loads through a base structure. Blanket piping services and auxiliary systems that interface with in-vessel components have played a major role in defining the overall device arrangement—concept details will be presented along with general arrangement features and preliminary results obtained from disruption analysis.« less

A Synthetical Two-Component Model with Peakon Solutions: One More Bi-Hamiltonian Case

NASA Astrophysics Data System (ADS)

Mengxia, Zhang; Xiaomin, Yang

2018-05-01

Compatible pairs of Hamiltonian operators for the synthetical two-component model of Xia, Qiao, and Zhou are derived systematically by means of the spectral gradient method. A new two-component system, which is bi-Hamiltonian, is presented. For this new system, the construction of its peakon solutions is considered.

A single-component multidrug transporter of the major facilitator superfamily is part of a network that protects E scherichia coli from bile salt stress

PubMed Central

Paul, Stephanie; Alegre, Kamela O; Holdsworth, Scarlett R; Rice, Matthew; Brown, James A; McVeigh, Paul; Kelly, Sharon M; Law, Christopher J

2014-01-01

Resistance to high concentrations of bile salts in the human intestinal tract is vital for the survival of enteric bacteria such as E scherichia coli. Although the tripartite AcrAB–TolC efflux system plays a significant role in this resistance, it is purported that other efflux pumps must also be involved. We provide evidence from a comprehensive suite of experiments performed at two different pH values (7.2 and 6.0) that reflect pH conditions that E . coli may encounter in human gut that MdtM, a single-component multidrug resistance transporter of the major facilitator superfamily, functions in bile salt resistance in E . coli by catalysing secondary active transport of bile salts out of the cell cytoplasm. Furthermore, assays performed on a chromosomal ΔacrB mutant transformed with multicopy plasmid encoding MdtM suggested a functional synergism between the single-component MdtM transporter and the tripartite AcrAB–TolC system that results in a multiplicative effect on resistance. Substrate binding experiments performed on purified MdtM demonstrated that the transporter binds to cholate and deoxycholate with micromolar affinity, and transport assays performed on inverted vesicles confirmed the capacity of MdtM to catalyse electrogenic bile salt/H+ antiport. PMID:24684269

Low-intensity electric fields induce two distinct response components in neocortical neuronal populations

PubMed Central

Xu, Weifeng; Wolff, Brian S.

2014-01-01

Low-intensity alternating electric fields applied to the scalp are capable of modulating cortical activity and brain functions, but the underlying mechanisms remain largely unknown. Here, we report two distinct components of voltage-sensitive dye signals induced by low-intensity, alternating electric fields in rodent cortical slices: a “passive component,” which corresponds to membrane potential changes directly induced by the electric field; and an “active component,” which is a widespread depolarization that is dependent on excitatory synaptic transmission. The passive component is stationary, with amplitude and phase accurately reflecting the cortical cytoarchitecture. In contrast, the active component is initiated from a local “hot spot” of activity and spreads to a large population as a propagating wave with rich local dynamics. The propagation of the active component may play a role in modulating large-scale cortical activity by spreading a low level of excitation from a small initiation point to a vast neuronal population. PMID:25122710

Multiple-component covalent organic frameworks

PubMed Central

Huang, Ning; Zhai, Lipeng; Coupry, Damien E.; Addicoat, Matthew A.; Okushita, Keiko; Nishimura, Katsuyuki; Heine, Thomas; Jiang, Donglin

2016-01-01

Covalent organic frameworks are a class of crystalline porous polymers that integrate molecular building blocks into periodic structures and are usually synthesized using two-component [1+1] condensation systems comprised of one knot and one linker. Here we report a general strategy based on multiple-component [1+2] and [1+3] condensation systems that enable the use of one knot and two or three linker units for the synthesis of hexagonal and tetragonal multiple-component covalent organic frameworks. Unlike two-component systems, multiple-component covalent organic frameworks feature asymmetric tiling of organic units into anisotropic skeletons and unusually shaped pores. This strategy not only expands the structural complexity of skeletons and pores but also greatly enhances their structural diversity. This synthetic platform is also widely applicable to multiple-component electron donor–acceptor systems, which lead to electronic properties that are not simply linear summations of those of the conventional [1+1] counterparts. PMID:27460607

Multiple-component covalent organic frameworks

NASA Astrophysics Data System (ADS)

Huang, Ning; Zhai, Lipeng; Coupry, Damien E.; Addicoat, Matthew A.; Okushita, Keiko; Nishimura, Katsuyuki; Heine, Thomas; Jiang, Donglin

2016-07-01

Covalent organic frameworks are a class of crystalline porous polymers that integrate molecular building blocks into periodic structures and are usually synthesized using two-component [1+1] condensation systems comprised of one knot and one linker. Here we report a general strategy based on multiple-component [1+2] and [1+3] condensation systems that enable the use of one knot and two or three linker units for the synthesis of hexagonal and tetragonal multiple-component covalent organic frameworks. Unlike two-component systems, multiple-component covalent organic frameworks feature asymmetric tiling of organic units into anisotropic skeletons and unusually shaped pores. This strategy not only expands the structural complexity of skeletons and pores but also greatly enhances their structural diversity. This synthetic platform is also widely applicable to multiple-component electron donor-acceptor systems, which lead to electronic properties that are not simply linear summations of those of the conventional [1+1] counterparts.

Haemophilus parasuis CpxRA two-component system confers bacterial tolerance to environmental stresses and macrolide resistance.

PubMed

Cao, Qi; Feng, Fenfen; Wang, Huan; Xu, Xiaojuan; Chen, Huanchun; Cai, Xuwang; Wang, Xiangru

2018-01-01

Haemophilus parasuis is an opportunistic pathogen localized in the upper respiratory tracts of pigs, its infection begins from bacterial survival under complex conditions, like hyperosmosis, oxidative stress, phagocytosis, and sometimes antibiotics as well. The two-component signal transduction (TCST) system serves as a common stimulus-response mechanism that allows microbes to sense and respond to diverse environmental conditions via a series of phosphorylation reactions. In this study, we investigated the role of TCST system CpxRA in H. parasuis in response to different environmental stimuli by constructing the ΔcpxA and ΔcpxR single deletion mutants as well as the ΔcpxRA double deletion mutant from H. parasuis serotype 4 isolate JS0135. We demonstrated that H. parasuis TCST system CpxRA confers bacterial tolerance to stresses and bactericidal antibiotics. The CpxR was found to play essential roles in mediating oxidative stress, osmotic stresses and alkaline pH stress tolerance, as well as macrolide resistance (i.e. erythromycin), but the CpxA deletion did not decrease bacterial resistance to abovementioned stresses. Moreover, we found via RT-qPCR approach that HAPS_RS00160 and HAPS_RS09425, both encoding multidrug efflux pumps, were significantly decreased in erythromycin challenged ΔcpxR and ΔcpxRA mutants compared with wild-type strain JS0135. These findings characterize the role of the TCST system CpxRA in H. parasuis conferring stress response tolerance and bactericidal resistance, which will deepen our understanding of the pathogenic mechanism in H. parasuis. Copyright © 2017 Elsevier GmbH. All rights reserved.

Two-component Gaussian core model: Strong-coupling limit, Bjerrum pairs, and gas-liquid phase transition.

PubMed

Frydel, Derek; Levin, Yan

2018-01-14

In the present work, we investigate a gas-liquid transition in a two-component Gaussian core model, where particles of the same species repel and those of different species attract. Unlike a similar transition in a one-component system with particles having attractive interactions at long separations and repulsive interactions at short separations, a transition in the two-component system is not driven solely by interactions but by a specific feature of the interactions, the correlations. This leads to extremely low critical temperature, as correlations are dominant in the strong-coupling limit. By carrying out various approximations based on standard liquid-state methods, we show that a gas-liquid transition of the two-component system poses a challenging theoretical problem.

Two-component Gaussian core model: Strong-coupling limit, Bjerrum pairs, and gas-liquid phase transition

NASA Astrophysics Data System (ADS)

Frydel, Derek; Levin, Yan

2018-01-01

In the present work, we investigate a gas-liquid transition in a two-component Gaussian core model, where particles of the same species repel and those of different species attract. Unlike a similar transition in a one-component system with particles having attractive interactions at long separations and repulsive interactions at short separations, a transition in the two-component system is not driven solely by interactions but by a specific feature of the interactions, the correlations. This leads to extremely low critical temperature, as correlations are dominant in the strong-coupling limit. By carrying out various approximations based on standard liquid-state methods, we show that a gas-liquid transition of the two-component system poses a challenging theoretical problem.

Scaled CMOS Reliability and Considerations for Spacecraft Systems: Bottom-Up and Top-Down Perspective

NASA Technical Reports Server (NTRS)

White, Mark

2012-01-01

New space missions will increasingly rely on more advanced technologies because of system requirements for higher performance, particularly in instruments and high-speed processing. Component-level reliability challenges with scaled CMOS in spacecraft systems from a bottom-up perspective have been presented. Fundamental Front-end and Back-end processing reliability issues with more aggressively scaled parts have been discussed. Effective thermal management from system-level to the componentlevel (top-down) is a key element in overall design of reliable systems. Thermal management in space systems must consider a wide range of issues, including thermal loading of many different components, and frequent temperature cycling of some systems. Both perspectives (top-down and bottom-up) play a large role in robust, reliable spacecraft system design.

The respiratory-vocal system of songbirds: anatomy, physiology, and neural control.

PubMed

Schmidt, Marc F; Martin Wild, J

2014-01-01

This wide-ranging review presents an overview of the respiratory-vocal system in songbirds, which are the only other vertebrate group known to display a degree of respiratory control during song rivalling that of humans during speech; this despite the fact that the peripheral components of both the respiratory and vocal systems differ substantially in the two groups. We first provide a brief description of these peripheral components in songbirds (lungs, air sacs and respiratory muscles, vocal organ (syrinx), upper vocal tract) and then proceed to a review of the organization of central respiratory-related neurons in the spinal cord and brainstem, the latter having an organization fundamentally similar to that of the ventral respiratory group of mammals. The second half of the review describes the nature of the motor commands generated in a specialized "cortical" song control circuit and how these might engage brainstem respiratory networks to shape the temporal structure of song. We also discuss a bilaterally projecting "respiratory-thalamic" pathway that links the respiratory system to "cortical" song control nuclei. This necessary pathway for song originates in the brainstem's primary inspiratory center and is hypothesized to play a vital role in synchronizing song motor commands both within and across hemispheres. © 2014 Elsevier B.V. All rights reserved.

The respiratory-vocal system of songbirds: Anatomy, physiology, and neural control

PubMed Central

Schmidt, Marc F.; Wild, J. Martin

2015-01-01

This wide-ranging review presents an overview of the respiratory-vocal system in songbirds, which are the only other vertebrate group known to display a degree of respiratory control during song rivalling that of humans during speech; this despite the fact that the peripheral components of both the respiratory and vocal systems differ substantially in the two groups. We first provide a brief description of these peripheral components in songbirds (lungs, air sacs and respiratory muscles, vocal organ (syrinx), upper vocal tract) and then proceed to a review of the organization of central respiratory-related neurons in the spinal cord and brainstem, the latter having an organization fundamentally similar to that of the ventral respiratory group of mammals. The second half of the review describes the nature of the motor commands generated in a specialized “cortical” song control circuit and how these might engage brainstem respiratory networks to shape the temporal structure of song. We also discuss a bilaterally projecting “respiratory-thalamic” pathway that links the respiratory system to “cortical” song control nuclei. This necessary pathway for song originates in the brainstem’s primary inspiratory center and is hypothesized to play a vital role in synchronizing song motor commands both within and across hemispheres. PMID:25194204

Multibody model reduction by component mode synthesis and component cost analysis

NASA Technical Reports Server (NTRS)

Spanos, J. T.; Mingori, D. L.

1990-01-01

The classical assumed-modes method is widely used in modeling the dynamics of flexible multibody systems. According to the method, the elastic deformation of each component in the system is expanded in a series of spatial and temporal functions known as modes and modal coordinates, respectively. This paper focuses on the selection of component modes used in the assumed-modes expansion. A two-stage component modal reduction method is proposed combining Component Mode Synthesis (CMS) with Component Cost Analysis (CCA). First, each component model is truncated such that the contribution of the high frequency subsystem to the static response is preserved. Second, a new CMS procedure is employed to assemble the system model and CCA is used to further truncate component modes in accordance with their contribution to a quadratic cost function of the system output. The proposed method is demonstrated with a simple example of a flexible two-body system.

Friend or foe? Reactive oxygen species production, scavenging and signaling in plant response to environmental stresses.

PubMed

Czarnocka, Weronika; Karpiński, Stanisław

2018-01-10

In the natural environment, plants are exposed to a variety of biotic and abiotic stress conditions that trigger rapid changes in the production and scavenging of reactive oxygen species (ROS). The production and scavenging of ROS is compartmentalized, which means that, depending on stimuli type, they can be generated and eliminated in different cellular compartments such as the apoplast, plasma membrane, chloroplasts, mitochondria, peroxisomes, and endoplasmic reticulum. Although the accumulation of ROS is generally harmful to cells, ROS play an important role in signaling pathways that regulate acclimatory and defense responses in plants, such as systemic acquired acclimation (SAA) and systemic acquired resistance (SAR). However, high accumulations of ROS can also trigger redox homeostasis disturbance which can lead to cell death, and in consequence, to a limitation in biomass and yield production. Different ROS have various half-lifetimes and degrees of reactivity toward molecular components such as lipids, proteins, and nucleic acids. Thus, they play different roles in intra- and extra-cellular signaling. Despite their possible damaging effect, ROS should mainly be considered as signaling molecules that regulate local and systemic acclimatory and defense responses. Over the past two decades it has been proven that ROS together with non-photochemical quenching (NPQ), hormones, Ca 2+ waves, and electrical signals are the main players in SAA and SAR, two physiological processes essential for plant survival and productivity in unfavorable conditions. Copyright © 2018. Published by Elsevier Inc.

Buckling of Aluminium Sheet Components

NASA Astrophysics Data System (ADS)

Hegadekatte, Vishwanath; Shi, Yihai; Nardini, Dubravko

Wrinkling is one of the major defects in sheet metal forming processes. It may become a serious obstacle to implementing the forming process and assembling the parts, and may also play a significant role in the wear of the tool. Wrinkling is essentially a local buckling phenomenon that results from compressive stresses (compressive instability) e.g., in the hoop direction for axi-symmetric systems such as beverage cans. Modern beverage can is a highly engineered product with a complex geometry. Therefore in order to understand wrinkling in such a complex system, we have started by studying wrinkling with the Yoshida buckling test. Further, we have studied the buckling of ideal and dented beverage cans under axial loading by laboratory testing. We have modelled the laboratory tests and also the imperfection sensitivity of the two systems using finite element method and the predictions are in qualitative agreement with experimental data.

Organo-erbium systems for optical amplification at telecommunications wavelengths.

PubMed

Ye, H Q; Li, Z; Peng, Y; Wang, C C; Li, T Y; Zheng, Y X; Sapelkin, A; Adamopoulos, G; Hernández, I; Wyatt, P B; Gillin, W P

2014-04-01

Modern telecommunications rely on the transmission and manipulation of optical signals. Optical amplification plays a vital part in this technology, as all components in a real telecommunications system produce some loss. The two main issues with present amplifiers, which rely on erbium ions in a glass matrix, are the difficulty in integration onto a single substrate and the need of high pump power densities to produce gain. Here we show a potential organic optical amplifier material that demonstrates population inversion when pumped from above using low-power visible light. This system is integrated into an organic light-emitting diode demonstrating that electrical pumping can be achieved. This opens the possibility of direct electrically driven optical amplifiers and optical circuits. Our results provide an alternative approach to producing low-cost integrated optics that is compatible with existing silicon photonics and a different route to an effective integrated optics technology.

Modeling and analysis of equipment managers in manufacturing execution systems for semiconductor packaging.

PubMed

Cheng, F T; Yang, H C; Luo, T L; Feng, C; Jeng, M

2000-01-01

Equipment Managers (EMs) play a major role in a Manufacturing Execution System (MES). They serve as the communication bridge between the components of an MES and the equipment. The purpose of this paper is to propose a novel methodology for developing analytical and simulation models for the EM such that the validity and performance of the EM can be evaluated. Domain knowledge and requirements are collected from a real semiconductor packaging factory. By using IDEFO and state diagrams, a static functional model and a dynamic state model of the EM are built. Next, these two models are translated into a Petri net model. This allows qualitative and quantitative analyses of the system. The EM net model is then expanded into the MES net model. Therefore, the performance of an EM in the MES environment can be evaluated. These evaluation results are good references for design and decision making.

Dynamic Systems Theory and Team Sport Coaching

ERIC Educational Resources Information Center

Gréhaigne, Jean-Francis; Godbout, Paul

2014-01-01

This article examines the theory of dynamic systems and its use in the domains of the study and coaching of team sports. The two teams involved in a match are looked at as two interacting systems in movement, where opposition is paramount. A key element for the observation of game play is the notion of configuration of play and its ever-changing…

General presentation including new structure

NASA Astrophysics Data System (ADS)

Soons, A.

2002-12-01

Electrical, electronic and electro-mechanical components play an essential role in the functional performance, quality, life cycle and costs of space systems. Their standardisation, product specification, development, evaluation, qualification and procurement must be based on a coherent and efficient approach, paying due attention to present and prospective European space policies and must be commensurate with user needs, market developments and technology trends. The European Space Components Coordination (ESCC) is established with the objective of harmonising the efforts concerning the various aspects of EEE space components by ESA. European national and international public space organisations, the component manufacturers and the user industries. The goal of the ESCC is to improve the availability of strategic EEE space components with the required performance and at affordable costs for institutional and commercial space programmes. It is the objective of ESCC to achieve this goal by harmonising the resources and development efforts for space components in the ESA Member States and by providing a single and unified system for the standardisation, product specification, evaluation, qualification and procurement of European EEE space components and for the certification of components and component manufacturers.

25 CFR 547.6 - What are the minimum technical standards for enrolling and enabling Class II gaming system...

Code of Federal Regulations, 2010 CFR

2010-04-01

... and enabling Class II gaming system components? 547.6 Section 547.6 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR HUMAN SERVICES MINIMUM TECHNICAL STANDARDS FOR GAMING EQUIPMENT USED WITH THE PLAY OF CLASS II GAMES § 547.6 What are the minimum technical standards for enrolling and...

Photometric study of two eclipsing binary stars: Light curve analysis and system parameters for GU CMa and SWASP J011732.10+525204.9

NASA Astrophysics Data System (ADS)

Shokry, A.; Saad, S. M.; Hamdy, M. A.; Beheary, M. M.; Abolazm, M. S.; Gadallah, K. A.; El-Depsey, M. H.; Al-Gazzar, M. S.

2018-02-01

A new photometric study of two eclipsing binary systems (GU CMa and SWASP J011732.10+525204.9) is presented. The accepted solutions of analyzing the light curves revealed that GU CMa is a semi-detached system consisting of two early spectral type components, (B2 and B2.5) while SWASP J011732.10+525204.9 is a contact binary with two late type components (K2 and M1). The primary component of each system is the massive one. The geometric configuration indicates that SWASP J011732.10+525204.9 passes through a very critical phase in which each component exactly fills its limited lobe with zero fill out ratio. New times of minimum and the absolute physical parameters for each system are determined. The evolution status for each system has been investigated.

Challenges of the Open Source Component Marketplace in the Industry

NASA Astrophysics Data System (ADS)

Ayala, Claudia; Hauge, Øyvind; Conradi, Reidar; Franch, Xavier; Li, Jingyue; Velle, Ketil Sandanger

The reuse of Open Source Software components available on the Internet is playing a major role in the development of Component Based Software Systems. Nevertheless, the special nature of the OSS marketplace has taken the “classical” concept of software reuse based on centralized repositories to a completely different arena based on massive reuse over Internet. In this paper we provide an overview of the actual state of the OSS marketplace, and report preliminary findings about how companies interact with this marketplace to reuse OSS components. Such data was gathered from interviews in software companies in Spain and Norway. Based on these results we identify some challenges aimed to improve the industrial reuse of OSS components.

General multicomponent Yajima-Oikawa system: Painlevé analysis, soliton solutions, and energy-sharing collisions.

PubMed

Kanna, T; Sakkaravarthi, K; Tamilselvan, K

2013-12-01

We consider the multicomponent Yajima-Oikawa (YO) system and show that the two-component YO system can be derived in a physical setting of a three-coupled nonlinear Schrödinger (3-CNLS) type system by the asymptotic reduction method. The derivation is further generalized to the multicomponent case. This set of equations describes the dynamics of nonlinear resonant interaction between a one-dimensional long wave and multiple short waves. The Painlevé analysis of the general multicomponent YO system shows that the underlying set of evolution equations is integrable for arbitrary nonlinearity coefficients which will result in three different sets of equations corresponding to positive, negative, and mixed nonlinearity coefficients. We obtain the general bright N-soliton solution of the multicomponent YO system in the Gram determinant form by using Hirota's bilinearization method and explicitly analyze the one- and two-soliton solutions of the multicomponent YO system for the above mentioned three choices of nonlinearity coefficients. We also point out that the 3-CNLS system admits special asymptotic solitons of bright, dark, anti-dark, and gray types, when the long-wave-short-wave resonance takes place. The short-wave component solitons undergo two types of energy-sharing collisions. Specifically, in the two-component YO system, we demonstrate that two types of energy-sharing collisions-(i) energy switching with opposite nature for a particular soliton in two components and (ii) similar kind of energy switching for a given soliton in both components-result for two different choices of nonlinearity coefficients. The solitons appearing in the long-wave component always exhibit elastic collision whereas those of short-wave components exhibit standard elastic collisions only for a specific choice of parameters. We have also investigated the collision dynamics of asymptotic solitons in the original 3-CNLS system. For completeness, we explore the three-soliton interaction and demonstrate the pairwise nature of collisions and unravel the fascinating state restoration property.

The Vocational Education Component of the Rhode Island Educational Management Information System.

ERIC Educational Resources Information Center

Galamaga, Donald P.; Bartolomeo, Paul A.

The document describes the implementation (Phase Two) of the Vocational Educational module--one component of an educational management information system. Phase Two entails the technical effort of final system design, final output specifications, edit specifications, system software selection, computer programing, systems documentation and the…

"RePlay Health": An Experiential Role-Playing Sport for Modeling Healthcare Decisions, Policies, and Outcomes.

PubMed

Kaufman, Geoff; Flanagan, Mary; Seidman, Max; Wien, Simone

2015-08-01

This article presents the design and empirical investigation of the "RePlay Health" game ( www.replayhealth.com/ ), a novel "role-playing sport" derived from a complex, data-driven, computational simulation of healthcare dynamics. By immersing players in a fictional world in which they take on the role of characters facing specific behavioral and environmental risk factors, the "RePlay Health" game models the impact of health and healthcare policy on individual-level livelihood and community-level productivity. A randomized experiment tested the efficacy of the game for inspiring shifts in thinking about public health and healthcare policy. This study compared the impact of actively playing the game versus passively spectating: 31 young adults were assigned to one of these two roles. Participants completed pretest and posttest measures of their subjective ranking of healthcare policies and attributions for health outcomes. Active players (compared with spectators) reported significantly higher prioritizations (from pretest to posttest) in their subjective ranking of several health policies modeled by the game, such as "improving postdischarge care" and "increasing access to healthy foods." Furthermore, players, but not spectators, were significantly more likely following gameplay to identify environmental or systemic factors as potential causes of health problems. The fact that significant results emerged with a 1-week gap between gameplay and measurement demonstrates that the game could exert a lasting impact on attitudes and perceptions. More broadly, this work illustrates the value of incorporating experiential components, such as narrative, embodiment, and role-playing, in designing efficacious games for health.

Imaging of Selenium by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in 2-D Electrophoresis Gels and Biological Tissues.

PubMed

Cruz, Elisa Castañeda Santa; Susanne Becker, J; Sabine Becker, J; Sussulini, Alessandra

2018-01-01

Selenium and selenoproteins are important components of living organisms that play a role in different biological processes. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a powerful analytical technique that has been employed to obtain distribution maps of selenium in biological tissues in a direct manner, as well as in selenoproteins, previously separated by their molecular masses and isoelectric points using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). In this chapter, we present the protocols to perform LA-ICP-MS imaging experiments, allowing the distribution visualization and determination of selenium and/or selenoproteins in biological systems.

Three-dimensional imaging technology offers promise in medicine.

PubMed

Karako, Kenji; Wu, Qiong; Gao, Jianjun

2014-04-01

Medical imaging plays an increasingly important role in the diagnosis and treatment of disease. Currently, medical equipment mainly has two-dimensional (2D) imaging systems. Although this conventional imaging largely satisfies clinical requirements, it cannot depict pathologic changes in 3 dimensions. The development of three-dimensional (3D) imaging technology has encouraged advances in medical imaging. Three-dimensional imaging technology offers doctors much more information on a pathology than 2D imaging, thus significantly improving diagnostic capability and the quality of treatment. Moreover, the combination of 3D imaging with augmented reality significantly improves surgical navigation process. The advantages of 3D imaging technology have made it an important component of technological progress in the field of medical imaging.

Initial Performance of the Attitude Control and Aspect Determination Subsystems on the Chandra Observatory

NASA Technical Reports Server (NTRS)

Cameron, R.; Aldcroft, T.; Podgorski, W. A.; Freeman, M. D.

2000-01-01

The aspect determination system of the Chandra X-ray Observatory plays a key role in realizing the full potential of Chandra's X-ray optics and detectors. We review the performance of the spacecraft hardware components and sub-systems, which provide information for both real time control of the attitude and attitude stability of the Chandra Observatory and also for more accurate post-facto attitude reconstruction. These flight components are comprised of the aspect camera (star tracker) and inertial reference units (gyros), plus the fiducial lights and fiducial transfer optics which provide an alignment null reference system for the science instruments and X-ray optics, together with associated thermal and structural components. Key performance measures will be presented for aspect camera focal plane data, gyro performance both during stable pointing and during maneuvers, alignment stability and mechanism repeatability.

LOV Histidine Kinase Modulates the General Stress Response System and Affects the virB Operon Expression in Brucella abortus

PubMed Central

Sycz, Gabriela; Carrica, Mariela Carmen; Tseng, Tong-Seung; Bogomolni, Roberto A.; Briggs, Winslow R.; Goldbaum, Fernando A.; Paris, Gastón

2015-01-01

Brucella is the causative agent of the zoonotic disease brucellosis, and its success as an intracellular pathogen relies on its ability to adapt to the harsh environmental conditions that it encounters inside the host. The Brucella genome encodes a sensor histidine kinase containing a LOV domain upstream from the kinase, LOVHK, which plays an important role in light-regulated Brucella virulence. In this report we study the intracellular signaling pathway initiated by the light sensor LOVHK using an integrated biochemical and genetic approach. From results of bacterial two-hybrid assays and phosphotransfer experiments we demonstrate that LOVHK functionally interacts with two response regulators: PhyR and LovR, constituting a functional two-component signal-transduction system. LOVHK contributes to the activation of the General Stress Response (GSR) system in Brucella via PhyR, while LovR is proposed to be a phosphate-sink for LOVHK, decreasing its phosphorylation state. We also show that in the absence of LOVHK the expression of the virB operon is down-regulated. In conclusion, our results suggest that LOVHK positively regulates the GSR system in vivo, and has an effect on the expression of the virB operon. The proposed regulatory network suggests a similar role for LOVHK in other microorganisms. PMID:25993430

Process-aware EHR BPM systems: two prototypes and a conceptual framework.

PubMed

Webster, Charles; Copenhaver, Mark

2010-01-01

Systematic methods to improve the effectiveness and efficiency of electronic health record-mediated processes will be key to EHRs playing an important role in the positive transformation of healthcare. Business process management (BPM) systematically optimizes process effectiveness, efficiency, and flexibility. Therefore BPM offers relevant ideas and technologies. We provide a conceptual model based on EHR productivity and negative feedback control that links EHR and BPM domains, describe two EHR BPM prototype modules, and close with the argument that typical EHRs must become more process-aware if they are to take full advantage of BPM ideas and technology. A prediction: Future extensible clinical groupware will coordinate delivery of EHR functionality to teams of users by combining modular components with executable process models whose usability (effectiveness, efficiency, and user satisfaction) will be systematically improved using business process management techniques.

Study of heterogeneous and reconfigurable architectures in the communication domain

NASA Astrophysics Data System (ADS)

Feldkaemper, H. T.; Blume, H.; Noll, T. G.

2003-05-01

One of the most challenging design issues for next generations of (mobile) communication systems is fulfilling the computational demands while finding an appropriate trade-off between flexibility and implementation aspects, especially power consumption. Flexibility of modern architectures is desirable, e.g. concerning adaptation to new standards and reduction of time-to-market of a new product. Typical target architectures for future communication systems include embedded FPGAs, dedicated macros as well as programmable digital signal and control oriented processor cores as each of these has its specific advantages. These will be integrated as a System-on-Chip (SoC). For such a heterogeneous architecture a design space exploration and an appropriate partitioning plays a crucial role. On the exemplary vehicle of a Viterbi decoder as frequently used in communication systems we show which costs in terms of ATE complexity arise implementing typical components on different types of architecture blocks. A factor of about seven orders of magnitude spans between a physically optimised implementation and an implementation on a programmable DSP kernel. An implementation on an embedded FPGA kernel is in between these two representing an attractive compromise with high flexibility and low power consumption. Extending this comparison to further components, it is shown quantitatively that the cost ratio between different implementation alternatives is closely related to the operation to be performed. This information is essential for the appropriate partitioning of heterogeneous systems.

Componentware Approaches in Management Information Systems

DTIC Science & Technology

2000-11-01

functionality. It offers plug & play readiness for service and is cooperative in combination with other programs Model ( Griffel 1998). The component view has...ISO195, DI199).terns: Elements of Reusable Object-Oriented Software.SAddison-Wesley 1995. Componentware approaches provide means that support Griffel

Research in remote sensing of vegetation

NASA Technical Reports Server (NTRS)

Schrumpf, Barry J.; Ripple, William J.; Isaacson, Dennis L.

1988-01-01

The research topics undertaken were primarily selected to further the understanding of fundamental relationships between electromagnetic energy measured from Earth orbiting satellites and terrestrial features, principally vegetation. Vegetation is an essential component in the soil formation process and the major factor in protecting and holding soil in place. Vegetation plays key roles in hydrological and nutrient cycles. Awareness of improvement or deterioration in the capacity of vegetation and the trends that those changes may indicate are, therefore, critical detections to make. A study of the relationships requires consideration of the various portions of the electromagnetic spectrum; characteristics of detector system; synergism that may be achieved by merging data from two or more detector systems or multiple dates of data; and vegetational characteristics. The vegetation of Oregon is sufficiently diverse as to provide ample opportunity to investigate the relationships suggested above several vegetation types.

Modular closed-loop control of diabetes.

PubMed

Patek, S D; Magni, L; Dassau, E; Karvetski, C; Toffanin, C; De Nicolao, G; Del Favero, S; Breton, M; Man, C Dalla; Renard, E; Zisser, H; Doyle, F J; Cobelli, C; Kovatchev, B P

2012-11-01

Modularity plays a key role in many engineering systems, allowing for plug-and-play integration of components, enhancing flexibility and adaptability, and facilitating standardization. In the control of diabetes, i.e., the so-called "artificial pancreas," modularity allows for the step-wise introduction of (and regulatory approval for) algorithmic components, starting with subsystems for assured patient safety and followed by higher layer components that serve to modify the patient's basal rate in real time. In this paper, we introduce a three-layer modular architecture for the control of diabetes, consisting in a sensor/pump interface module (IM), a continuous safety module (CSM), and a real-time control module (RTCM), which separates the functions of insulin recommendation (postmeal insulin for mitigating hyperglycemia) and safety (prevention of hypoglycemia). In addition, we provide details of instances of all three layers of the architecture: the APS© serving as the IM, the safety supervision module (SSM) serving as the CSM, and the range correction module (RCM) serving as the RTCM. We evaluate the performance of the integrated system via in silico preclinical trials, demonstrating 1) the ability of the SSM to reduce the incidence of hypoglycemia under nonideal operating conditions and 2) the ability of the RCM to reduce glycemic variability.

On modal cross-coupling in the asymptotic modal limit

NASA Astrophysics Data System (ADS)

Culver, Dean; Dowell, Earl

2018-03-01

The conditions under which significant modal cross-coupling occurs in dynamical systems responding to high-frequency, broadband forcing that excites many modes is studied. The modal overlap factor plays a key role in the analysis of these systems as the modal density (the ratio of number of modes to the frequency bandwidth) becomes large. The modal overlap factor is effectively the ratio of the width of a resonant peak (the damping ratio times the resonant frequency) to the average frequency interval between resonant peaks (or rather, the inverse of the modal density). It is shown that this parameter largely determines whether substantial modal cross-coupling occurs in a given system's response. Here, two prototypical systems are considered. The first is a simple rectangular plate whose significant modal cross-coupling is the exception rather than the norm. The second is a pair of rectangular plates attached at a point where significant modal cross-coupling is more likely to occur. We show that, for certain cases of modal density and damping, non-negligible cross coupling occurs in both systems. Under similar circumstances, the constraint force between the two plates in the latter system becomes broadband. The implications of this for using Asymptotic Modal Analysis (AMA) in multi-component systems are discussed.

Bottom boundary layer forced by finite amplitude long and short surface waves motions

NASA Astrophysics Data System (ADS)

Elsafty, H.; Lynett, P.

2018-04-01

A multiple-scale perturbation approach is implemented to solve the Navier-Stokes equations while including bottom boundary layer effects under a single wave and under two interacting waves. In this approach, fluid velocities and the pressure field are decomposed into two components: a potential component and a rotational component. In this study, the two components are exist throughout the entire water column and each is scaled with appropriate length and time scales. A one-way coupling between the two components is implemented. The potential component is assumed to be known analytically or numerically a prior, and the rotational component is forced by the potential component. Through order of magnitude analysis, it is found that the leading-order coupling between the two components occurs through the vertical convective acceleration. It is shown that this coupling plays an important role in the bottom boundary layer behavior. Its effect on the results is discussed for different wave-forcing conditions: purely harmonic forcing and impurely harmonic forcing. The approach is then applied to derive the governing equations for the bottom boundary layer developed under two interacting wave motions. Both motions-the shorter and the longer wave-are decomposed into two components, potential and rotational, as it is done in the single wave. Test cases are presented wherein two different wave forcings are simulated: (1) two periodic oscillatory motions and (2) short waves interacting with a solitary wave. The analysis of the two periodic motions indicates that nonlinear effects in the rotational solution may be significant even though nonlinear effects are negligible in the potential forcing. The local differences in the rotational velocity due to the nonlinear vertical convection coupling term are found to be on the order of 30% of the maximum boundary layer velocity for the cases simulated in this paper. This difference is expected to increase with the increase in wave nonlinearity.

Circadian Rhythm Connections to Oxidative Stress: Implications for Human Health

PubMed Central

Wilking, Melissa; Ndiaye, Mary; Mukhtar, Hasan

2013-01-01

Abstract Significance: Oxygen and circadian rhythmicity are essential in a myriad of physiological processes to maintain homeostasis, from blood pressure and sleep/wake cycles, down to cellular signaling pathways that play critical roles in health and disease. If the human body or cells experience significant stress, their ability to regulate internal systems, including redox levels and circadian rhythms, may become impaired. At cellular as well as organismal levels, impairment in redox regulation and circadian rhythms may lead to a number of adverse effects, including the manifestation of a variety of diseases such as heart diseases, neurodegenerative conditions, and cancer. Recent Advances: Researchers have come to an understanding as to the basics of the circadian rhythm mechanism, as well as the importance of the numerous species of oxidative stress components. The effects of oxidative stress and dysregulated circadian rhythms have been a subject of intense investigations since they were first discovered, and recent investigations into the molecular mechanisms linking the two have started to elucidate the bases of their connection. Critical Issues: While much is known about the mechanics and importance of oxidative stress systems and circadian rhythms, the front where they interact has had very little research focused on it. This review discusses the idea that these two systems are together intricately involved in the healthy body, as well as in disease. Future Directions: We believe that for a more efficacious management of diseases that have both circadian rhythm and oxidative stress components in their pathogenesis, targeting both systems in tandem would be far more successful. Antioxid. Redox Signal. 19, 192–208 PMID:23198849

Integrating knowledge representation and quantitative modelling in physiology.

PubMed

de Bono, Bernard; Hunter, Peter

2012-08-01

A wealth of potentially shareable resources, such as data and models, is being generated through the study of physiology by computational means. Although in principle the resources generated are reusable, in practice, few can currently be shared. A key reason for this disparity stems from the lack of consistent cataloguing and annotation of these resources in a standardised manner. Here, we outline our vision for applying community-based modelling standards in support of an automated integration of models across physiological systems and scales. Two key initiatives, the Physiome Project and the European contribution - the Virtual Phsysiological Human Project, have emerged to support this multiscale model integration, and we focus on the role played by two key components of these frameworks, model encoding and semantic metadata annotation. We present examples of biomedical modelling scenarios (the endocrine effect of atrial natriuretic peptide, and the implications of alcohol and glucose toxicity) to illustrate the role that encoding standards and knowledge representation approaches, such as ontologies, could play in the management, searching and visualisation of physiology models, and thus in providing a rational basis for healthcare decisions and contributing towards realising the goal of of personalized medicine. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer

NASA Astrophysics Data System (ADS)

Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

2012-10-01

It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 μs. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

[Immune system and tumors].

PubMed

Terme, Magali; Tanchot, Corinne

2017-02-01

Despite having been much debated, it is now well established that the immune system plays an essential role in the fight against cancer. In this article, we will highlight the implication of the immune system in the control of tumor growth and describe the major components of the immune system involved in the antitumoral immune response. The immune system, while exerting pressure on tumor cells, also will play a pro-tumoral role by sculpting the immunogenicity of tumors cells as they develop. Finally, we will illustrate the numerous mechanisms of immune suppression that take place within the tumoral microenvironment which allow tumor cells to escape control from the immune system. The increasingly precise knowledge of the brakes to an effective antitumor immune response allows the development of immunotherapy strategies more and more innovating and promising of hope. Copyright © 2016. Published by Elsevier Masson SAS.

Pharmacological effects of Chinese herb aconite (fuzi) on cardiovascular system.

PubMed

Zhao, Dandan; Wang, Jie; Cui, Yanjing; Wu, Xinfang

2012-09-01

Fuzi (aconite, Radix Aconiti praeparata), a widely used Chinese herb, plays a significant role in the cardiovascular system. This is mainly reflected by Fuzi's cardiotonic effect, its protective effect on myocardial cells, and its effect on heart rate and rhythm, blood pressure, and hemodynamics. In this article, the pharmacological effects and the corresponding mechanisms of Fuzi (aconite) and its active components on cardiovascular system are reviewed.

The RNA-binding protein CsrA plays a central role in positively regulating virulence factors in Erwinia amylovora

PubMed Central

Ancona, Veronica; Lee, Jae Hoon; Zhao, Youfu

2016-01-01

The GacS/GacA two-component system (also called GrrS/GrrA) is a global regulatory system which is highly conserved among gamma-proteobacteria. This system positively regulates non-coding small regulatory RNA csrB, which in turn binds to the RNA-binding protein CsrA. However, how GacS/GacA-Csr system regulates virulence traits in E. amylovora remains unknown. Results from mutant characterization showed that the csrB mutant was hypermotile, produced higher amount of exopolysaccharide amylovoran, and had increased expression of type III secretion (T3SS) genes in vitro. In contrast, the csrA mutant exhibited complete opposite phenotypes, including non-motile, reduced amylovoran production and expression of T3SS genes. Furthermore, the csrA mutant did not induce hypersensitive response on tobacco or cause disease on immature pear fruits, indicating that CsrA is a positive regulator of virulence factors. These findings demonstrated that CsrA plays a critical role in E. amylovora virulence and suggested that negative regulation of virulence by GacS/GacA acts through csrB sRNA, which binds to CsrA and neutralizes its positive effect on T3SS gene expression, flagellar formation and amylovoran production. Future research will be focused on determining the molecular mechanism underlying the positive regulation of virulence traits by CsrA. PMID:27845410

The RNA-binding protein CsrA plays a central role in positively regulating virulence factors in Erwinia amylovora.

PubMed

Ancona, Veronica; Lee, Jae Hoon; Zhao, Youfu

2016-11-15

The GacS/GacA two-component system (also called GrrS/GrrA) is a global regulatory system which is highly conserved among gamma-proteobacteria. This system positively regulates non-coding small regulatory RNA csrB, which in turn binds to the RNA-binding protein CsrA. However, how GacS/GacA-Csr system regulates virulence traits in E. amylovora remains unknown. Results from mutant characterization showed that the csrB mutant was hypermotile, produced higher amount of exopolysaccharide amylovoran, and had increased expression of type III secretion (T3SS) genes in vitro. In contrast, the csrA mutant exhibited complete opposite phenotypes, including non-motile, reduced amylovoran production and expression of T3SS genes. Furthermore, the csrA mutant did not induce hypersensitive response on tobacco or cause disease on immature pear fruits, indicating that CsrA is a positive regulator of virulence factors. These findings demonstrated that CsrA plays a critical role in E. amylovora virulence and suggested that negative regulation of virulence by GacS/GacA acts through csrB sRNA, which binds to CsrA and neutralizes its positive effect on T3SS gene expression, flagellar formation and amylovoran production. Future research will be focused on determining the molecular mechanism underlying the positive regulation of virulence traits by CsrA.

Robust high-performance control for robotic manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1991-01-01

Model-based and performance-based control techniques are combined for an electrical robotic control system. Thus, two distinct and separate design philosophies have been merged into a single control system having a control law formulation including two distinct and separate components, each of which yields a respective signal component that is combined into a total command signal for the system. Those two separate system components include a feedforward controller and a feedback controller. The feedforward controller is model-based and contains any known part of the manipulator dynamics that can be used for on-line control to produce a nominal feedforward component of the system's control signal. The feedback controller is performance-based and consists of a simple adaptive PID controller which generates an adaptive control signal to complement the nominal feedforward signal.

Three-particle correlation functions of quasi-two-dimensional one-component and binary colloid suspensions.

PubMed

Ho, Hau My; Lin, Binhua; Rice, Stuart A

2006-11-14

We report the results of experimental determinations of the triplet correlation functions of quasi-two-dimensional one-component and binary colloid suspensions in which the colloid-colloid interaction is short ranged. The suspensions studied range in density from modestly dilute to solid. The triplet correlation function of the one-component colloid system reveals extensive ordering deep in the liquid phase. At the same density the ordering of the larger diameter component in a binary colloid system is greatly diminished by a very small amount of the smaller diameter component. The possible utilization of information contained in the triplet correlation function in the theory of melting of a quasi-two-dimensional system is briefly discussed.

Asynchronous Two-Level Checkpointing Scheme for Large-Scale Adjoints in the Spectral-Element Solver Nek5000

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schanen, Michel; Marin, Oana; Zhang, Hong

Adjoints are an important computational tool for large-scale sensitivity evaluation, uncertainty quantification, and derivative-based optimization. An essential component of their performance is the storage/recomputation balance in which efficient checkpointing methods play a key role. We introduce a novel asynchronous two-level adjoint checkpointing scheme for multistep numerical time discretizations targeted at large-scale numerical simulations. The checkpointing scheme combines bandwidth-limited disk checkpointing and binomial memory checkpointing. Based on assumptions about the target petascale systems, which we later demonstrate to be realistic on the IBM Blue Gene/Q system Mira, we create a model of the expected performance of our checkpointing approach and validatemore » it using the highly scalable Navier-Stokes spectralelement solver Nek5000 on small to moderate subsystems of the Mira supercomputer. In turn, this allows us to predict optimal algorithmic choices when using all of Mira. We also demonstrate that two-level checkpointing is significantly superior to single-level checkpointing when adjoining a large number of time integration steps. To our knowledge, this is the first time two-level checkpointing had been designed, implemented, tuned, and demonstrated on fluid dynamics codes at large scale of 50k+ cores.« less

Structural Similitude and Scaling Laws

NASA Technical Reports Server (NTRS)

Simitses, George J.

1998-01-01

Aircraft and spacecraft comprise the class of aerospace structures that require efficiency and wisdom in design, sophistication and accuracy in analysis and numerous and careful experimental evaluations of components and prototype, in order to achieve the necessary system reliability, performance and safety. Preliminary and/or concept design entails the assemblage of system mission requirements, system expected performance and identification of components and their connections as well as of manufacturing and system assembly techniques. This is accomplished through experience based on previous similar designs, and through the possible use of models to simulate the entire system characteristics. Detail design is heavily dependent on information and concepts derived from the previous steps. This information identifies critical design areas which need sophisticated analyses, and design and redesign procedures to achieve the expected component performance. This step may require several independent analysis models, which, in many instances, require component testing. The last step in the design process, before going to production, is the verification of the design. This step necessitates the production of large components and prototypes in order to test component and system analytical predictions and verify strength and performance requirements under the worst loading conditions that the system is expected to encounter in service. Clearly then, full-scale testing is in many cases necessary and always very expensive. In the aircraft industry, in addition to full-scale tests, certification and safety necessitate large component static and dynamic testing. Such tests are extremely difficult, time consuming and definitely absolutely necessary. Clearly, one should not expect that prototype testing will be totally eliminated in the aircraft industry. It is hoped, though, that we can reduce full-scale testing to a minimum. Full-scale large component testing is necessary in other industries as well, Ship building, automobile and railway car construction all rely heavily on testing. Regardless of the application, a scaled-down (by a large factor) model (scale model) which closely represents the structural behavior of the full-scale system (prototype) can prove to be an extremely beneficial tool. This possible development must be based on the existence of certain structural parameters that control the behavior of a structural system when acted upon by static and/or dynamic loads. If such structural parameters exist, a scaled-down replica can be built, which will duplicate the response of the full-scale system. The two systems are then said to be structurally similar. The term, then, that best describes this similarity is structural similitude. Similarity of systems requires that the relevant system parameters be identical and these systems be governed by a unique set of characteristic equations. Thus, if a relation or equation of variables is written for a system, it is valid for all systems which are similar to it. Each variable in a model is proportional to the corresponding variable of the prototype. This ratio, which plays an essential role in predicting the relationship between the model and its prototype, is called the scale factor.

Utility and Reliability of an App for the System for Observing Play and Recreation in Communities (iSOPARC®)

ERIC Educational Resources Information Center

Santos, Maria P. M.; Rech, Cassiano R.; Alberico, Claudia O.; Fermino, Rogério C.; Rios, Ana P.; David, João; Reis, Rodrigo S.; Sarmiento, Olga L.; McKenzie, Thomas L.; Mota, Jorge

2016-01-01

The app for the System for Observing Play and Recreation in Communities (iSOPARC®) was developed to enhance System for Observing Play and Recreation in Communities data collection and management. The study aim was to examine the usability and inter-rater reliability of iSOPARC®. Trained observers collected data in 16 park areas in two Latin…

Feedback loops and temporal misalignment in component-based hydrologic modeling

NASA Astrophysics Data System (ADS)

Elag, Mostafa M.; Goodall, Jonathan L.; Castronova, Anthony M.

2011-12-01

In component-based modeling, a complex system is represented as a series of loosely integrated components with defined interfaces and data exchanges that allow the components to be coupled together through shared boundary conditions. Although the component-based paradigm is commonly used in software engineering, it has only recently been applied for modeling hydrologic and earth systems. As a result, research is needed to test and verify the applicability of the approach for modeling hydrologic systems. The objective of this work was therefore to investigate two aspects of using component-based software architecture for hydrologic modeling: (1) simulation of feedback loops between components that share a boundary condition and (2) data transfers between temporally misaligned model components. We investigated these topics using a simple case study where diffusion of mass is modeled across a water-sediment interface. We simulated the multimedia system using two model components, one for the water and one for the sediment, coupled using the Open Modeling Interface (OpenMI) standard. The results were compared with a more conventional numerical approach for solving the system where the domain is represented by a single multidimensional array. Results showed that the component-based approach was able to produce the same results obtained with the more conventional numerical approach. When the two components were temporally misaligned, we explored the use of different interpolation schemes to minimize mass balance error within the coupled system. The outcome of this work provides evidence that component-based modeling can be used to simulate complicated feedback loops between systems and guidance as to how different interpolation schemes minimize mass balance error introduced when components are temporally misaligned.

Playing Tic-Tac-Toe with a Sugar-Based Molecular Computer.

PubMed

Elstner, M; Schiller, A

2015-08-24

Today, molecules can perform Boolean operations and circuits at a level of higher complexity. However, concatenation of logic gates and inhomogeneous inputs and outputs are still challenging tasks. Novel approaches for logic gate integration are possible when chemical programming and software programming are combined. Here it is shown that a molecular finite automaton based on the concatenated implication function (IMP) of a fluorescent two-component sugar probe via a wiring algorithm is able to play tic-tac-toe.

Autonomous navigation system. [gyroscopic pendulum for air navigation

NASA Technical Reports Server (NTRS)

Merhav, S. J. (Inventor)

1981-01-01

An inertial navigation system utilizing a servo-controlled two degree of freedom pendulum to obtain specific force components in the locally level coordinate system is described. The pendulum includes a leveling gyroscope and an azimuth gyroscope supported on a two gimbal system. The specific force components in the locally level coordinate system are converted to components in the geographical coordinate system by means of a single Euler transformation. The standard navigation equations are solved to determine longitudinal and lateral velocities. Finally, vehicle position is determined by a further integration.

Robustness mechanisms in primate societies: a perturbation study

PubMed Central

Flack, Jessica C; Krakauer, David C; de Waal, Frans B. M

2005-01-01

Conflict management mechanisms have a direct, critical effect on system robustness because they mitigate conflict intensity and help repair damaged relationships. However, robustness mechanisms can also have indirect effects on system integrity by facilitating interactions among components. We explore the indirect role that conflict management mechanisms play in the maintenance of social system robustness, using a perturbation technique to ‘knockout’ components responsible for effective conflict management. We explore the effects of knockout on pigtailed macaque (Macaca nemestrina) social organization, using a captive group of 84 individuals. This system is ideal in addressing this question because there is heterogeneity in performance of conflict management. Consequently, conflict managers can be easily removed without disrupting other control structures. We find that powerful conflict managers are essential in maintaining social order for the benefit of all members of society. We show that knockout of components responsible for conflict management results in system destabilization by significantly increasing mean levels of conflict and aggression, decreasing socio-positive interaction and decreasing the operation of repair mechanisms. PMID:16024369

Mechanism of the pH-Induced Conformational Change in the Sensor Domain of the DraK Histidine Kinase via the E83, E105, and E107 Residues

PubMed Central

Jee, Jun-Goo; Lee, Jae Kyoung; Kim, Hyo Jeong; Park, Jin-Wan; Kim, Eun-Hee; Hwang, Eunha; Kim, Sang-Yoon; Lee, Eun-Gyeong; Kwon, Ohsuk; Cheong, Hae-Kap

2014-01-01

The DraR/DraK two-component system was found to be involved in the differential regulation of antibiotic biosynthesis in a medium-dependent manner; however, its function and signaling and sensing mechanisms remain unclear. Here, we describe the solution structure of the extracellular sensor domain of DraK and suggest a mechanism for the pH-dependent conformational change of the protein. The structure contains a mixed alpha-beta fold, adopting a fold similar to the ubiquitous sensor domain of histidine kinase. A biophysical study demonstrates that the E83, E105, and E107 residues have abnormally high pKa values and that they drive the pH-dependent conformational change for the extracellular sensor domain of DraK. We found that a triple mutant (E83L/E105L/E107A) is pH independent and mimics the low pH structure. An in vivo study showed that DraK is essential for the recovery of the pH of Streptomyces coelicolor growth medium after acid shock. Our findings suggest that the DraR/DraK two-component system plays an important role in the pH regulation of S. coelicolor growth medium. This study provides a foundation for the regulation and the production of secondary metabolites in Streptomyces. PMID:25203403

Mechanism of the pH-induced conformational change in the sensor domain of the DraK Histidine kinase via the E83, E105, and E107 residues.

PubMed

Yeo, Kwon Joo; Hong, Young-Soo; Jee, Jun-Goo; Lee, Jae Kyoung; Kim, Hyo Jeong; Park, Jin-Wan; Kim, Eun-Hee; Hwang, Eunha; Kim, Sang-Yoon; Lee, Eun-Gyeong; Kwon, Ohsuk; Cheong, Hae-Kap

2014-01-01

The DraR/DraK two-component system was found to be involved in the differential regulation of antibiotic biosynthesis in a medium-dependent manner; however, its function and signaling and sensing mechanisms remain unclear. Here, we describe the solution structure of the extracellular sensor domain of DraK and suggest a mechanism for the pH-dependent conformational change of the protein. The structure contains a mixed alpha-beta fold, adopting a fold similar to the ubiquitous sensor domain of histidine kinase. A biophysical study demonstrates that the E83, E105, and E107 residues have abnormally high pKa values and that they drive the pH-dependent conformational change for the extracellular sensor domain of DraK. We found that a triple mutant (E83L/E105L/E107A) is pH independent and mimics the low pH structure. An in vivo study showed that DraK is essential for the recovery of the pH of Streptomyces coelicolor growth medium after acid shock. Our findings suggest that the DraR/DraK two-component system plays an important role in the pH regulation of S. coelicolor growth medium. This study provides a foundation for the regulation and the production of secondary metabolites in Streptomyces.

Interaction of dissolution, sorption and biodegradation on transport of BTEX in a saturated groundwater system: Numerical modeling and spatial moment analysis

NASA Astrophysics Data System (ADS)

Valsala, Renu; Govindarajan, Suresh Kumar

2018-06-01

Interaction of various physical, chemical and biological transport processes plays an important role in deciding the fate and migration of contaminants in groundwater systems. In this study, a numerical investigation on the interaction of various transport processes of BTEX in a saturated groundwater system is carried out. In addition, the multi-component dissolution from a residual BTEX source under unsteady flow conditions is incorporated in the modeling framework. The model considers Benzene, Toluene, Ethyl Benzene and Xylene dissolving from the residual BTEX source zone to undergo sorption and aerobic biodegradation within the groundwater aquifer. Spatial concentration profiles of dissolved BTEX components under the interaction of various sorption and biodegradation conditions have been studied. Subsequently, a spatial moment analysis is carried out to analyze the effect of interaction of various transport processes on the total dissolved mass and the mobility of dissolved BTEX components. Results from the present numerical study suggest that the interaction of dissolution, sorption and biodegradation significantly influence the spatial distribution of dissolved BTEX components within the saturated groundwater system. Mobility of dissolved BTEX components is also found to be affected by the interaction of these transport processes.

Environmental Stability and Oxidation Behavior of HfO2-Si and YbGd(O) Based Environmental Barrier Coating Systems for SiCSiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Farmer, Serene; McCue, Terry R.; Harder, Bryan; Hurst, Janet B.

2017-01-01

Ceramic environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft propulsion systems because of their ability to significantly increase engine operating temperatures, improve component durability, reduce engine weight and cooling requirements. Advanced EBC systems for SiCSiC CMC turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant material development challenges for the high temperature CMC components is to develop prime-reliant, environmental durable environmental barrier coating systems. In this paper, the durability and performance of advanced Electron Beam-Physical Vapor Deposition (EB-PVD) NASA HfO2-Si and YbGdSi(O) EBC bond coat top coat systems for SiCSiC CMC have been summarized. The high temperature thermomechanical creep, fatigue and oxidation resistance have been investigated in the laboratory simulated high-heat-flux environmental test conditions. The advanced NASA EBC systems showed promise to achieve 1500C temperature capability, helping enable next generation turbine engines with significantly improved engine component temperature capability and durability.

Structural Basis for DNA Recognition by the Two-Component Response Regulator RcsB.

PubMed

Filippova, Ekaterina V; Zemaitaitis, Bozena; Aung, Theint; Wolfe, Alan J; Anderson, Wayne F

2018-02-27

RcsB is a highly conserved transcription regulator of the Rcs phosphorelay system, a complex two-component signal transduction system (N. Majdalani and S. Gottesman, Annu Rev Microbiol 59:379-405, 2005; A. J. Wolfe, Curr Opin Microbiol 13:204-209, 2010, https://doi.org/10.1016/j.mib.2010.01.002; D. J. Clarke, Future Microbiol 5:1173-1184, 2010, https://doi.org/10.2217/fmb.10.83). RcsB plays an important role in virulence and pathogenicity in human hosts by regulating biofilm formation. RcsB can regulate transcription alone or together with its auxiliary transcription regulators by forming heterodimers. This complexity allows RcsB to regulate transcription of more than 600 bacterial genes in response to different stresses (D. Wang et al., Mol Plant Microbe Interact 25:6-17, 2012, https://doi.org/10.1094/MPMI-08-11-0207). Despite increasing knowledge of RcsB importance, molecular mechanisms that drive the ability of RcsB to control transcription of a large number of genes remain unclear. Here, we present crystal structures of unphosphorylated RcsB in complex with the consensus DNA-binding sequence of 22-mer (DNA22) and 18-mer (DNA18) of the flhDC operon from Escherichia coli determined at 3.15- and 3.37-Å resolution, respectively. The results of our structural analysis combined with the results of in vitro binding assays provide valuable insights to the protein regulatory mechanism, demonstrate how RcsB recognizes target DNA sequences, and reveal a unique oligomeric state that allows RcsB to form homo- and heterodimers. This information will help us understand the complex mechanisms of transcriptional regulation by RcsB in bacteria. IMPORTANCE RcsB is a well-studied two-component response regulator of the Rcs phosphorelay system, conserved within the family Enterobacteriaceae , which includes many pathogens. It is a global regulator, controlling more than 5% of bacterial genes associated with capsule biosynthesis, flagellar biogenesis, cell wall biosynthesis, antibiotic resistance, biofilm formation, and virulence in pathogens. Knowledge of RcsB structure represents a unique opportunity to explore mechanisms that regulate the Rcs phosphorelay system and its role in the family Enterobacteriaceae . Copyright © 2018 Filippova et al.

Phosphotransfer reactions of the CbbRRS three-protein two- component system from Rhodopseudomonas palustris CGA010 appear to be controlled by an internal molecular switch on the sensor kinase.

PubMed

Romagnoli, Simona; Tabita, F Robert

2007-01-01

The CbbRRS system is an atypical three-protein two-component system that modulates the expression of the cbb(I) CO(2) fixation operon of Rhodopseudomonas palustris, possibly in response to a redox signal. It consists of a membrane-bound hybrid sensor kinase, CbbSR, with a transmitter and receiver domain, and two response regulator proteins, CbbRR1 and CbbRR2. No detectable helix-turn-helix DNA binding domain is associated with either response regulator, but an HPt domain and a second receiver domain are predicted at the C-terminal region of CbbRR1 and CbbRR2, respectively. The abundance of conserved residues predicted to participate in a His-Asp phosphorelay raised the question of their de facto involvement. In this study, the role of the multiple receiver domains was elucidated in vitro by generating site-directed mutants of the putative conserved residues. Distinct phosphorylation patterns were obtained with two truncated versions of the hybrid sensor kinase, CbbSR(T189) and CbbSR(R96) (CbbSR beginning at residues T189 and R96, respectively). These constructs also exhibited substantially different affinities for ATP and phosphorylation stability, which was found to be dependent on a conserved Asp residue (Asp-696) within the kinase receiver domain. Asp-696 also played an important role in defining the specificity of phosphorylation for response regulators CbbRR1 or CbbRR2, and this residue appeared to act in conjunction with residues within the region from Arg-96 to Thr-189 at the N terminus of the sensor kinase. The net effect of concerted interactions at these distinct regions of CbbSR created an internal molecular switch that appears to coordinate a unique branched phosphorelay system.

Breadth and depth involvement: Understanding Internet gambling involvement and its relationship to gambling problems.

PubMed

LaPlante, Debi A; Nelson, Sarah E; Gray, Heather M

2014-06-01

The "involvement effect" refers to the finding that controlling for gambling involvement often reduces or eliminates frequently observed game-specific associations with problem gambling. In other words, broader patterns of gambling behavior, particularly the number of types of games played over a defined period, contribute more to problem gambling than playing specific games (e.g., lottery, casino, Internet gambling). This study extends this burgeoning area of inquiry in three primary ways. First, it tests independently and simultaneously the predictive power of two gambling patterns: breadth involvement (i.e., the number of games an individual plays) and depth involvement (i.e., the number of days an individual plays). Second, it includes the first involvement analyses of actual betting activity records that are associated with clinical screening information. Third, it evaluates and compares the linearity of breadth and depth effects. We conducted analyses of the actual gambling activity of 1,440 subscribers to the bwin.party gambling service who completed an online gambling disorder screen. In all, 11 of the 16 games we examined had a significant univariate association with a positive screen for gambling disorder. However, after controlling for breadth involvement, only Live Action Internet sports betting retained a significant relationship with potential gambling-related problems. Depth involvement, though significantly related to potential problems, did not impact game-based gambling disorder associations as much as breadth involvement. Finally, breadth effects appeared steeply linear, with a slight quadratic component manifesting beyond four games played, but depth effects appeared to have a strong linear component and a slight cubic component.

Reducing Sibling Conflict in Maltreated Children Placed in Foster Homes

PubMed Central

Linares, L. Oriana; Jimenez, Jessica; Nesci, Cristina; Pearson, Eva; Beller, Sarah; Edwards, Nancy; Levin-Rector, Alison

2016-01-01

Sibling aggression among maltreated children placed in foster homes is linked to other externalizing problems and placement disruption. The reduction of sibling conflict and aggression may be achieved via a multicomponent ecologically focused intervention for families in the foster care system. The focus of the study is to evaluate the feasibility and short-term effectiveness of a transtheoretical intervention model targeting sibling pairs and their foster parent that integrates family systems, social learning theory, and a conflict mediation perspective. In this pilot study, sibling pairs (N=22) and their foster parent were randomized into a three-component intervention (n=13) or a comparison (n=9) group. Promoting Sibling Bonds (PSB) is an 8-week prevention intervention targeting maltreated sibling pairs ages 5–11 years placed together in a foster home. The Siblings, Parent, and Joint components were delivered in a program package at the foster agency by a trained two-clinician team. Average attendance across program components was 73%. Outcomes in four areas were gathered at pre-and post-intervention: observed sibling interaction quality (positive and negative) including conflict during play, and foster parent reports of mediation strategies and sibling aggression in the foster home. At post-intervention, adjusting for baseline scores and child age, intervention pairs showed higher positive (p<.001) and negative (p<.05) interaction quality, and lower sibling conflict during play (p <.01) than comparison pairs. Foster parents in the intervention group reported a higher number of conflict mediation strategies than those in the comparison group (p <.001). Foster parents in the intervention group reported lower sibling physical aggression from the older toward the younger child than those in the comparison group (p <.05). Data suggest that the PSB intervention is a promising approach to reduce conflict and promote parental mediation which together may reduce sibling aggression in the foster home. PMID:24585072

Reducing sibling conflict in maltreated children placed in foster homes.

PubMed

Linares, L Oriana; Jimenez, Jessica; Nesci, Cristina; Pearson, Eva; Beller, Sarah; Edwards, Nancy; Levin-Rector, Alison

2015-02-01

Sibling aggression among maltreated children placed in foster homes is linked to other externalizing problems and placement disruption. The reduction of sibling conflict and aggression may be achieved via a multicomponent ecologically focused intervention for families in the foster care system. The focus of the study is to evaluate the feasibility and short-term effectiveness of a transtheoretical intervention model targeting sibling pairs and their foster parent that integrates family systems, social learning theory, and a conflict mediation perspective. In this pilot study, sibling pairs (N = 22) and their foster parent were randomized into a three-component intervention (n = 13) or a comparison (n = 9) group. Promoting Sibling Bonds (PSB) is an 8-week prevention intervention targeting maltreated sibling pairs ages 5-11 years placed together in a foster home. The siblings, parent, and joint components were delivered in a program package at the foster agency by a trained two-clinician team. Average attendance across program components was 73 %. Outcomes in four areas were gathered at pre- and postintervention: observed sibling interaction quality (positive and negative) including conflict during play, and foster parent reports of mediation strategies and sibling aggression in the foster home. At postintervention, adjusting for baseline scores and child age, intervention pairs showed higher positive (p < 0.001) and negative (p < 0.05) interaction quality and lower sibling conflict during play (p < 0.01) than comparison pairs. Foster parents in the intervention group reported a higher number of conflict mediation strategies than those in the comparison group (p < 0.001). Foster parents in the intervention group reported lower sibling physical aggression from the older toward the younger child than those in the comparison group (p < 0.05). Data suggest that the PSB intervention is a promising approach to reduce conflict and promote parental mediation, which together may reduce sibling aggression in the foster home.

Two-lattice models of trace element behavior: A response

NASA Astrophysics Data System (ADS)

Ellison, Adam J. G.; Hess, Paul C.

1990-08-01

Two-lattice melt components of Bottinga and Weill (1972), Nielsen and Drake (1979), and Nielsen (1985) are applied to major and trace element partitioning between coexisting immiscible liquids studied by RYERSON and Hess (1978) and Watson (1976). The results show that (1) the set of components most successful in one system is not necessarily portable to another system; (2) solution non-ideality within a sublattice severely limits applicability of two-lattice models; (3) rigorous application of two-lattice melt components may yield effective partition coefficients for major element components with no physical interpretation; and (4) the distinction between network-forming and network-modifying components in the sense of the two-lattice models is not clear cut. The algebraic description of two-lattice models is such that they will most successfully limit the compositional dependence of major and trace element solution behavior when the effective partition coefficient of the component of interest is essentially the same as the bulk partition coefficient of all other components within its sublattice.

Co-regulation of polysaccharide production, motility, and expression of type III secretion genes by EnvZ/OmpR and GrrS/GrrA systems in Erwinia amylovora.

PubMed

Li, Wenting; Ancona, Veronica; Zhao, Youfu

2014-02-01

The EnvZ/OmpR and GrrS/GrrA systems, two widely distributed two-component systems in gamma-Proteobacteria, negatively control amylovoran biosynthesis in Erwinia amylovora, and the two systems regulate motility in an opposing manner. In this study, we examined the interplay of EnvZ/OmpR and GrrS/GrrA systems in controlling various virulence traits in E. amylovora. Results showed that amylovoran production was significantly higher when both systems were inactivated, indicating that the two systems act as negative regulators and their combined effect on amylovoran production appears to be enhanced. In contrast, reduced motility was observed when both systems were deleted as compared to that of grrA/grrS mutants and WT strain, indicating that the two systems antagonistically regulate motility in E. amylovora. In addition, glycogen accumulation was much higher in envZ/ompR and two triple mutants than that of grrS/grrA mutants and WT strain, suggesting that EnvZ/OmpR plays a dominant role in regulating glycogen accumulation, whereas levan production was significantly lower in the grrS/grrA and two triple mutants as compared with that of WT and envZ/ompR mutants, indicating that GrrS/GrrA system dominantly controls levan production. Furthermore, both systems negatively regulated expression of three type III secretion (T3SS) genes and their combined negative effect on hrp-T3SS gene expression increased when both systems were deleted. These results demonstrated that EnvZ/OmpR and GrrS/GrrA systems co-regulate various virulence factors in E. amylovora by still unknown mechanisms or through different target genes, sRNAs, or proteins, indicating that a complex regulatory network may be involved, which needs to be further explored.

Chemical Form of Selenium in Naturally Selenium-Rich Lentils (Lens Culinaris L.) From Saskatchewan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thavarajah, D.; Vandenberg, A.; George, G.N.

2009-06-04

Lentils (Lens culinaris L.) are a source of many essential dietary components and trace elements for human health. In this study we show that lentils grown in the Canadian prairies are additionally enriched in selenium, an essential micronutrient needed for general well-being, including a healthy immune system and protection against cancer. Selenium K near-edge X-ray absorption spectroscopy (XAS) has been used to examine the selenium biochemistry of two lentil cultivars grown in various locations in Saskatchewan, Canada. We observe significant variations in total selenium concentration with geographic location and cultivar; however, almost all the selenium (86--95%) in these field-grown lentilsmore » is present as organic selenium modeled as selenomethionine with a small component (5--14%) as selenate. As the toxicities of certain forms of arsenic and selenium are antagonistic, selenium-rich lentils may have a pivotal role to play in alleviating the chronic arsenic poisoning in Bangladesh.« less

The endogenous opioid system: a common substrate in drug addiction.

PubMed

Trigo, José Manuel; Martin-García, Elena; Berrendero, Fernando; Robledo, Patricia; Maldonado, Rafael

2010-05-01

Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits that involve several neurotransmitters. One of the neurochemical systems that plays a pivotal role in different aspects of addiction is the endogenous opioid system (EOS). Opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within these reward circuits. Chronic exposure to the different prototypical drugs of abuse, including opioids, alcohol, nicotine, psychostimulants and cannabinoids has been reported to produce significant alterations within the EOS, which seem to play an important role in the development of the addictive process. In this review, we will describe the adaptive changes produced by different drugs of abuse on the EOS, and the current knowledge about the contribution of each component of this neurobiological system to their addictive properties.

Two Heteromeric Kinesin Complexes in Chemosensory Neurons and Sensory Cilia of Caenorhabditis elegans

PubMed Central

Signor, Dawn; Wedaman, Karen P.; Rose, Lesilee S.; Scholey, Jonathan M.

1999-01-01

Chemosensation in the nervous system of the nematode Caenorhabditis elegans depends on sensory cilia, whose assembly and maintenance requires the transport of components such as axonemal proteins and signal transduction machinery to their site of incorporation into ciliary structures. Members of the heteromeric kinesin family of microtubule motors are prime candidates for playing key roles in these transport events. Here we describe the molecular characterization and partial purification of two heteromeric kinesin complexes from C. elegans, heterotrimeric CeKinesin-II and dimeric CeOsm-3. Transgenic worms expressing green fluorescent protein driven by endogenous heteromeric kinesin promoters reveal that both CeKinesin-II and CeOsm-3 are expressed in amphid, inner labial, and phasmid chemosensory neurons. Additionally, immunolocalization experiments on fixed worms show an intense concentration of CeKinesin-II and CeOsm-3 polypeptides in the ciliated endings of these chemosensory neurons and a punctate localization pattern in the corresponding cell bodies and dendrites. These results, together with the phenotypes of known mutants in the pathway of sensory ciliary assembly, suggest that CeKinesin-II and CeOsm-3 drive the transport of ciliary components required for sequential steps in the assembly of chemosensory cilia. PMID:9950681

Gene ercA, encoding a putative iron-containing alcohol dehydrogenase, is involved in regulation of ethanol utilization in Pseudomonas aeruginosa.

PubMed

Hempel, Niels; Görisch, Helmut; Mern, Demissew S

2013-09-01

Several two-component regulatory systems are known to be involved in the signal transduction pathway of the ethanol oxidation system in Pseudomonas aeruginosa ATCC 17933. These sensor kinases and response regulators are organized in a hierarchical manner. In addition, a cytoplasmic putative iron-containing alcohol dehydrogenase (Fe-ADH) encoded by ercA (PA1991) has been identified to play an essential role in this regulatory network. The gene ercA (PA1991) is located next to ercS, which encodes a sensor kinase. Inactivation of ercA (PA1991) by insertion of a kanamycin resistance cassette created mutant NH1. NH1 showed poor growth on various alcohols. On ethanol, NH1 grew only with an extremely extended lag phase. During the induction period on ethanol, transcription of structural genes exa and pqqABCDEH, encoding components of initial ethanol oxidation in P. aeruginosa, was drastically reduced in NH1, which indicates the regulatory function of ercA (PA1991). However, transcription in the extremely delayed logarithmic growth phase was comparable to that in the wild type. To date, the involvement of an Fe-ADH in signal transduction processes has not been reported.

Gene ercA, Encoding a Putative Iron-Containing Alcohol Dehydrogenase, Is Involved in Regulation of Ethanol Utilization in Pseudomonas aeruginosa

PubMed Central

Hempel, Niels; Görisch, Helmut

2013-01-01

Several two-component regulatory systems are known to be involved in the signal transduction pathway of the ethanol oxidation system in Pseudomonas aeruginosa ATCC 17933. These sensor kinases and response regulators are organized in a hierarchical manner. In addition, a cytoplasmic putative iron-containing alcohol dehydrogenase (Fe-ADH) encoded by ercA (PA1991) has been identified to play an essential role in this regulatory network. The gene ercA (PA1991) is located next to ercS, which encodes a sensor kinase. Inactivation of ercA (PA1991) by insertion of a kanamycin resistance cassette created mutant NH1. NH1 showed poor growth on various alcohols. On ethanol, NH1 grew only with an extremely extended lag phase. During the induction period on ethanol, transcription of structural genes exa and pqqABCDEH, encoding components of initial ethanol oxidation in P. aeruginosa, was drastically reduced in NH1, which indicates the regulatory function of ercA (PA1991). However, transcription in the extremely delayed logarithmic growth phase was comparable to that in the wild type. To date, the involvement of an Fe-ADH in signal transduction processes has not been reported. PMID:23813731

Two single-point mutations shift the ligand selectivity of a pheromone receptor between two closely related moth species

PubMed Central

Yang, Ke; Huang, Ling-Qiao; Ning, Chao

2017-01-01

Male moths possess highly sensitive and selective olfactory systems that detect sex pheromones produced by their females. Pheromone receptors (PRs) play a key role in this process. The PR HassOr14b is found to be tuned to (Z)−9-hexadecenal, the major sex-pheromone component, in Helicoverpa assulta. HassOr14b is co-localized with HassOr6 or HassOr16 in two olfactory sensory neurons within the same sensilla. As HarmOr14b, the ortholog of HassOr14b in the closely related species Helicoverpa armigera, is tuned to another chemical (Z)−9-tetradecenal, we study the amino acid residues that determine their ligand selectivity. Two amino acids located in the intracellular domains F232I and T355I together determine the functional difference between the two orthologs. We conclude that species-specific changes in the tuning specificity of the PRs in the two Helicoverpa moth species could be achieved with just a few amino acid substitutions, which provides new insights into the evolution of closely related moth species. PMID:29063835

Earth Without Life: A Systems Model of a Global Abiotic Nitrogen Cycle

NASA Astrophysics Data System (ADS)

Laneuville, M.; Kameya, M.; Cleaves, H. J.

2017-07-01

N is the major component of the atmosphere and plays important roles in biochemistry. Presently, the surface N-cycle is dominated by biology. However, before the origin of life, abiotic N-cycling would have set the stage for the origin of life.

Distributed Learning Metadata Standards

ERIC Educational Resources Information Center

McClelland, Marilyn

2004-01-01

Significant economies can be achieved in distributed learning systems architected with a focus on interoperability and reuse. The key building blocks of an efficient distributed learning architecture are the use of standards and XML technologies. The goal of plug and play capability among various components of a distributed learning system…

Game-theoretic strategies for asymmetric networked systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, Nageswara S.; Ma, Chris Y. T.; Hausken, Kjell

Abstract—We consider an infrastructure consisting of a network of systems each composed of discrete components that can be reinforced at a certain cost to guard against attacks. The network provides the vital connectivity between systems, and hence plays a critical, asymmetric role in the infrastructure operations. We characterize the system-level correlations using the aggregate failure correlation function that specifies the infrastructure failure probability given the failure of an individual system or network. The survival probabilities of systems and network satisfy first-order differential conditions that capture the component-level correlations. We formulate the problem of ensuring the infrastructure survival as a gamemore » between anattacker and a provider, using the sum-form and product-form utility functions, each composed of a survival probability term and a cost term. We derive Nash Equilibrium conditions which provide expressions for individual system survival probabilities, and also the expected capacity specified by the total number of operational components. These expressions differ only in a single term for the sum-form and product-form utilities, despite their significant differences.We apply these results to simplified models of distributed cloud computing infrastructures.« less

Increasing the Automation and Autonomy for Spacecraft Operations with Criteria Action Table

NASA Technical Reports Server (NTRS)

Li, Zhen-Ping; Savki, Cetin

2005-01-01

The Criteria Action Table (CAT) is an automation tool developed for monitoring real time system messages for specific events and processes in order to take user defined actions based on a set of user-defined rules. CAT was developed by Lockheed Martin Space Operations as a part of a larger NASA effort at the Goddard Space Flight Center (GSFC) to create a component-based, middleware-based, and standard-based general purpose ground system architecture referred as GMSEC - the GSFC Mission Services Evolution Center. CAT has been integrated into the upgraded ground systems for Tropical Rainfall Measuring Mission (TRMM) and Small Explorer (SMEX) satellites and it plays the central role in their automation effort to reduce the cost and increase the reliability for spacecraft operations. The GMSEC architecture provides a standard communication interface and protocol for components to publish/describe messages to an information bus. It also provides a standard message definition so components can send and receive messages to the bus interface rather than each other, thus reducing the component-to-component coupling, interface, protocols, and link (socket) management. With the GMSEC architecture, components can publish standard event messages to the bus for all nominal, significant, and surprising events in regard to satellite, celestial, ground system, or any other activity. In addition to sending standard event messages, each GMSEC compliant component is required to accept and process GMSEC directive request messages.

What’s in a game? A systems approach to enhancing performance analysis in football

PubMed Central

2017-01-01

Purpose Performance analysis (PA) in football is considered to be an integral component of understanding the requirements for optimal performance. Despite vast amounts of research in this area key gaps remain, including what comprises PA in football, and methods to minimise research-practitioner gaps. The aim of this study was to develop a model of the football match system in order to better describe and understand the components of football performance. Such a model could inform the design of new PA methods. Method Eight elite level football Subject Method Experts (SME’s) participated in two workshops to develop a systems model of the football match system. The model was developed using a first-of-its-kind application of Cognitive Work Analysis (CWA) in football. CWA has been used in many other non-sporting domains to analyse and understand complex systems. Result Using CWA, a model of the football match ‘system’ was developed. The model enabled identification of several PA measures not currently utilised, including communication between team members, adaptability of teams, playing at the appropriate tempo, as well as attacking and defending related measures. Conclusion The results indicate that football is characteristic of a complex sociotechnical system, and revealed potential new and unique PA measures regarded as important by SME’s, yet not currently measured. Importantly, these results have identified a gap between the current PA research and the information that is meaningful to football coaches and practitioners. PMID:28212392

Computational Methods for Biomolecular Electrostatics

PubMed Central

Dong, Feng; Olsen, Brett; Baker, Nathan A.

2008-01-01

An understanding of intermolecular interactions is essential for insight into how cells develop, operate, communicate and control their activities. Such interactions include several components: contributions from linear, angular, and torsional forces in covalent bonds, van der Waals forces, as well as electrostatics. Among the various components of molecular interactions, electrostatics are of special importance because of their long range and their influence on polar or charged molecules, including water, aqueous ions, and amino or nucleic acids, which are some of the primary components of living systems. Electrostatics, therefore, play important roles in determining the structure, motion and function of a wide range of biological molecules. This chapter presents a brief overview of electrostatic interactions in cellular systems with a particular focus on how computational tools can be used to investigate these types of interactions. PMID:17964951

The Integrated Safety-Critical Advanced Avionics Communication and Control (ISAACC) System Concept: Infrastructure for ISHM

NASA Technical Reports Server (NTRS)

Gwaltney, David A.; Briscoe, Jeri M.

2005-01-01

Integrated System Health Management (ISHM) architectures for spacecraft will include hard real-time, critical subsystems and soft real-time monitoring subsystems. Interaction between these subsystems will be necessary and an architecture supporting multiple criticality levels will be required. Demonstration hardware for the Integrated Safety-Critical Advanced Avionics Communication & Control (ISAACC) system has been developed at NASA Marshall Space Flight Center. It is a modular system using a commercially available time-triggered protocol, ?Tp/C, that supports hard real-time distributed control systems independent of the data transmission medium. The protocol is implemented in hardware and provides guaranteed low-latency messaging with inherent fault-tolerance and fault-containment. Interoperability between modules and systems of modules using the TTP/C is guaranteed through definition of messages and the precise message schedule implemented by the master-less Time Division Multiple Access (TDMA) communications protocol. "Plug-and-play" capability for sensors and actuators provides automatically configurable modules supporting sensor recalibration and control algorithm re-tuning without software modification. Modular components of controlled physical system(s) critical to control algorithm tuning, such as pumps or valve components in an engine, can be replaced or upgraded as "plug and play" components without modification to the ISAACC module hardware or software. ISAACC modules can communicate with other vehicle subsystems through time-triggered protocols or other communications protocols implemented over Ethernet, MIL-STD- 1553 and RS-485/422. Other communication bus physical layers and protocols can be included as required. In this way, the ISAACC modules can be part of a system-of-systems in a vehicle with multi-tier subsystems of varying criticality. The goal of the ISAACC architecture development is control and monitoring of safety critical systems of a manned spacecraft. These systems include spacecraft navigation and attitude control, propulsion, automated docking, vehicle health management and life support. ISAACC can integrate local critical subsystem health management with subsystems performing long term health monitoring. The ISAACC system and its relationship to ISHM will be presented.

A Framework for Enhancing Real-time Social Media Data to Improve Disaster Management Process

NASA Astrophysics Data System (ADS)

Attique Shah, Syed; Zafer Şeker, Dursun; Demirel, Hande

2018-05-01

Social Media datasets are playing a vital role to provide information that can support decision making in nearly all domains of technology. It is due to the fact that social media is a quick and economical approach for data collection from public through methods like crowdsourcing. It is already proved by existing research that in case of any disaster (natural or man-made) the information extracted from Social Media sites is very critical to Disaster Management Systems for response and reconstruction. This study comprises of two components, the first part proposes a framework that provides updated and filtered real time input data for the disaster management system through social media and the second part consists of a designed web user API for a structured and defined real time data input process. This study contributes to the discipline of design science for the information systems domain. The aim of this study is to propose a framework that can filter and organize data from the unstructured social media sources through recognized methods and to bring this retrieved data to the same level as that of taken through a structured and predefined mechanism of a web API. Both components are designed to a level such that they can potentially collaborate and produce updated information for a disaster management system to carry out accurate and effective.

Cascading Failures and Recovery in Networks of Networks

NASA Astrophysics Data System (ADS)

Havlin, Shlomo

Network science have been focused on the properties of a single isolated network that does not interact or depends on other networks. In reality, many real-networks, such as power grids, transportation and communication infrastructures interact and depend on other networks. I will present a framework for studying the vulnerability and the recovery of networks of interdependent networks. In interdependent networks, when nodes in one network fail, they cause dependent nodes in other networks to also fail. This is also the case when some nodes like certain locations play a role in two networks -multiplex. This may happen recursively and can lead to a cascade of failures and to a sudden fragmentation of the system. I will present analytical solutions for the critical threshold and the giant component of a network of n interdependent networks. I will show, that the general theory has many novel features that are not present in the classical network theory. When recovery of components is possible global spontaneous recovery of the networks and hysteresis phenomena occur and the theory suggests an optimal repairing strategy of system of systems. I will also show that interdependent networks embedded in space are significantly more vulnerable compared to non embedded networks. In particular, small localized attacks may lead to cascading failures and catastrophic consequences.Thus, analyzing data of real network of networks is highly required to understand the system vulnerability. DTRA, ONR, Israel Science Foundation.

Information management of a department of diagnostic imaging.

PubMed

Vincenzoni, M; Campioni, P; Vecchioli Scaldazza, A; Capocasa, G; Marano, P

1998-01-01

It is well-known that while RIS allows the management of all input and output data of a Radiology service, PACS plays a major role in the management of all radiologic images. However, the two systems should be closely integrated: scheduling of a radiologic exam requires direct automated integration with the system of image management for retrieval of previous exams and storage of the exam just completed. A modern information system of integration of data and radiologic images should be based on an automated work flow management in al its components, being at the same time flexible and compatible with the ward organization to support and computerize each stage of the working process. Similarly, standard protocols (DICOM 3.0, HL7) defined for interfacing with the Diagnostic Imaging (D.I.) department and the other components of modules of a modern HIS, should be used. They ensure the system to be expandable and accessible to ensure share and integration of information with HIS, emergency service or wards. Correct RIS/PACS integration allows a marked improvement in the efficiency of a modern D.I. department with a positive impact on the daily activity, prompt availability of previous data and images with sophisticated handling of diagnostic images to enhance the reporting quality. The increased diffusion of internet and intranet technology predicts future developments still to be discovered.

RegA Plays a Key Role in Oxygen-Dependent Establishment of Persistence and in Isocitrate Lyase Activity, a Critical Determinant of In vivo Brucella suis Pathogenicity

PubMed Central

Abdou, Elias; Jiménez de Bagüés, María P.; Martínez-Abadía, Ignacio; Ouahrani-Bettache, Safia; Pantesco, Véronique; Occhialini, Alessandra; Al Dahouk, Sascha; Köhler, Stephan; Jubier-Maurin, Véronique

2017-01-01

For aerobic human pathogens, adaptation to hypoxia is a critical factor for the establishment of persistent infections, as oxygen availability is low inside the host. The two-component system RegB/A of Brucella suis plays a central role in the control of respiratory systems adapted to oxygen deficiency, and in persistence in vivo. Using an original “in vitro model of persistence” consisting in gradual oxygen depletion, we compared transcriptomes and proteomes of wild-type and ΔregA strains to identify the RegA-regulon potentially involved in the set-up of persistence. Consecutive to oxygen consumption resulting in growth arrest, 12% of the genes in B. suis were potentially controlled directly or indirectly by RegA, among which numerous transcriptional regulators were up-regulated. In contrast, genes or proteins involved in envelope biogenesis and in cellular division were repressed, suggesting a possible role for RegA in the set-up of a non-proliferative persistence state. Importantly, the greatest number of the RegA-repressed genes and proteins, including aceA encoding the functional IsoCitrate Lyase (ICL), were involved in energy production. A potential consequence of this RegA impact may be the slowing-down of the central metabolism as B. suis progressively enters into persistence. Moreover, ICL is an essential determinant of pathogenesis and long-term interactions with the host, as demonstrated by the strict dependence of B. suis on ICL activity for multiplication and persistence during in vivo infection. RegA regulates gene or protein expression of all functional groups, which is why RegA is a key regulator of B. suis in adaptation to oxygen depletion. This function may contribute to the constraint of bacterial growth, typical of chronic infection. Oxygen-dependent activation of two-component systems that control persistence regulons, shared by several aerobic human pathogens, has not been studied in Brucella sp. before. This work therefore contributes significantly to the unraveling of persistence mechanisms in this important zoonotic pathogen. PMID:28573107

Integrated Geologic and Geophysical Approach for Establishing Geothermal Play Fairways and Discovering Blind Geothermal Systems in the Great Basin Region, Western USA: A Progress Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faulds, James E.; Hinz, Nicholas H.; Coolbaugh, Mark F.

We have undertaken an integrated geologic, geochemical, and geophysical study of a broad 240-km-wide, 400-km-long transect stretching from west-central to eastern Nevada in the Great Basin region of the western USA. The main goal of this study is to produce a comprehensive geothermal potential map that incorporates up to 11 parameters and identifies geothermal play fairways that represent potential blind or hidden geothermal systems. Our new geothermal potential map incorporates: 1) heat flow; 2) geochemistry from springs and wells; 3) structural setting; 4) recency of faulting; 5) slip rates on Quaternary faults; 6) regional strain rate; 7) slip and dilationmore » tendency on Quaternary faults; 8) seismologic data; 9) gravity data; 10) magnetotelluric data (where available); and 11) seismic reflection data (primarily from the Carson Sink and Steptoe basins). The transect is respectively anchored on its western and eastern ends by regional 3D modeling of the Carson Sink and Steptoe basins, which will provide more detailed geothermal potential maps of these two promising areas. To date, geological, geochemical, and geophysical data sets have been assembled into an ArcGIS platform and combined into a preliminary predictive geothermal play fairway model using various statistical techniques. The fairway model consists of the following components, each of which are represented in grid-cell format in ArcGIS and combined using specified weights and mathematical operators: 1) structural component of permeability; 2) regional-scale component of permeability; 3) combined permeability, and 4) heat source model. The preliminary model demonstrates that the multiple data sets can be successfully combined into a comprehensive favorability map. An initial evaluation using known geothermal systems as benchmarks to test interpretations indicates that the preliminary modeling has done a good job assigning relative ranks of geothermal potential. However, a major challenge is defining logical relative rankings of each parameter and how best to combine the multiple data sets into the geothermal potential/ permeability map. Ongoing feedback and data analysis are in use to revise the grouping and weighting of some parameters in order to develop a more robust, optimized, final model. The final product will incorporate more parameters into a geothermal potential map than any previous effort in the region and may serve as a prototype to develop comprehensive geothermal potential maps for other regions.« less

ITER Construction—Plant System Integration

NASA Astrophysics Data System (ADS)

Tada, E.; Matsuda, S.

2009-02-01

This brief paper introduces how the ITER will be built in the international collaboration. The ITER Organization plays a central role in constructing ITER and leading it into operation. Since most of the ITER components are to be provided in-kind from the member countries, integral project management should be scoped in advance of real work. Those include design, procurement, system assembly, testing, licensing and commissioning of ITER.

78 FR 31576 - Enforcement Proceeding; Certain Two-Way Global Satellite Communication Devices, System and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-24

...-Way Global Satellite Communication Devices, System and Components Thereof; Notice of Institution of...-confidential documents filed in connection with this investigation are or will be available for inspection... importation of certain two-way global satellite communication devices, system and components thereof by reason...

Social play in bonobos (Pan paniscus) and chimpanzees (Pan troglodytes): Implications for natural social systems and interindividual relationships.

PubMed

Palagi, Elisabetta

2006-03-01

This study compares adult play behavior in the two Pan species in order to test the effects of phylogenetic closeness and the nature of social systems on play distribution. The social play (both with fertile and immature subjects) performed by adults did not differ between the two species. In contrast, in bonobos, play levels among fertile subjects were higher than in chimpanzees. Findings regarding levels of undecided conflicts (more frequent in bonobos) and formal submission displays (lacking in bonobos) confirm, in the two colonies under study, that bonobos exhibit "egalitarianism" more than chimpanzees. Some authors emphasized the importance of play-fighting for social assessment when relationships among individuals are not codified and structured according to rank-rules. Indeed, adult bonobos played more roughly than chimpanzees. Moreover, adult bonobos displayed the full play-face at a high frequency especially during rough play sessions, whereas in chimpanzees, the frequency of play signals was not affected by roughness of play. The frequency of social play among bonobo females was higher than in any other sex combinations, whereas no difference was found for chimpanzees. As a matter of fact, social play can be viewed as a balance between cooperation and competition. Among bonobo females, characterized by social competence and affiliation, social play might enhance their behavioral flexibility and increase their socially symmetrical relationships which, after all, are the basis for their egalitarian society. (c) 2005 Wiley-Liss, Inc.

The Pseudomonas aeruginosa AlgZR two-component system coordinates multiple phenotypes

PubMed Central

Okkotsu, Yuta; Little, Alexander S.; Schurr, Michael J.

2014-01-01

Pseudomonas aeruginosa is an opportunistic pathogen that causes a multitude of infections. These infections can occur at almost any site in the body and are usually associated with a breach of the innate immune system. One of the prominent sites where P. aeruginosa causes chronic infections is within the lungs of cystic fibrosis patients. P. aeruginosa uses two-component systems that sense environmental changes to differentially express virulence factors that cause both acute and chronic infections. The P. aeruginosa AlgZR two component system is one of its global regulatory systems that affects the organism's fitness in a broad manner. This two-component system is absolutely required for two P. aeruginosa phenotypes: twitching motility and alginate production, indicating its importance in both chronic and acute infections. Additionally, global transcriptome analyses indicate that it regulates the expression of many different genes, including those associated with quorum sensing, type IV pili, type III secretion system, anaerobic metabolism, cyanide and rhamnolipid production. This review examines the complex AlgZR regulatory network, what is known about the structure and function of each protein, and how it relates to the organism's ability to cause infections. PMID:24999454

Comparative analysis of the Photorhabdus luminescens and the Yersinia enterocolitica genomes: uncovering candidate genes involved in insect pathogenicity

PubMed Central

Heermann, Ralf; Fuchs, Thilo M

2008-01-01

Background Photorhabdus luminescens and Yersinia enterocolitica are both enteric bacteria which are associated with insects. P. luminescens lives in symbiosis with soil nematodes and is highly pathogenic towards insects but not to humans. In contrast, Y. enterocolitica is widely found in the environment and mainly known to cause gastroenteritis in men, but has only recently been shown to be also toxic for insects. It is expected that both pathogens share an overlap of genetic determinants that play a role within the insect host. Results A selective genome comparison was applied. Proteins belonging to the class of two-component regulatory systems, quorum sensing, universal stress proteins, and c-di-GMP signalling have been analysed. The interorganismic synopsis of selected regulatory systems uncovered common and distinct signalling mechanisms of both pathogens used for perception of signals within the insect host. Particularly, a new class of LuxR-like regulators was identified, which might be involved in detecting insect-specific molecules. In addition, the genetic overlap unravelled a two-component system that is unique for the genera Photorhabdus and Yersinia and is therefore suggested to play a major role in the pathogen-insect relationship. Our analysis also highlights factors of both pathogens that are expressed at low temperatures as encountered in insects in contrast to higher (body) temperature, providing evidence that temperature is a yet under-investigated environmental signal for bacterial adaptation to various hosts. Common degradative metabolic pathways are described that might be used to explore nutrients within the insect gut or hemolymph, thus enabling the proliferation of P. luminescens and Y. enterocolitica in their invertebrate hosts. A strikingly higher number of genes encoding insecticidal toxins and other virulence factors in P. luminescens compared to Y. enterocolitica correlates with the higher virulence of P. luminescens towards insects, and suggests a putative broader insect host spectrum of this pathogen. Conclusion A set of factors shared by the two pathogens was identified including those that are involved in the host infection process, in persistence within the insect, or in host exploitation. Some of them might have been selected during the association with insects and then adapted to pathogenesis in mammalian hosts. PMID:18221513

Normalization of neuronal responses in cortical area MT across signal strengths and motion directions

PubMed Central

Xiao, Jianbo; Niu, Yu-Qiong; Wiesner, Steven

2014-01-01

Multiple visual stimuli are common in natural scenes, yet it remains unclear how multiple stimuli interact to influence neuronal responses. We investigated this question by manipulating relative signal strengths of two stimuli moving simultaneously within the receptive fields (RFs) of neurons in the extrastriate middle temporal (MT) cortex. Visual stimuli were overlapping random-dot patterns moving in two directions separated by 90°. We first varied the motion coherence of each random-dot pattern and characterized, across the direction tuning curve, the relationship between neuronal responses elicited by bidirectional stimuli and by the constituent motion components. The tuning curve for bidirectional stimuli showed response normalization and can be accounted for by a weighted sum of the responses to the motion components. Allowing nonlinear, multiplicative interaction between the two component responses significantly improved the data fit for some neurons, and the interaction mainly had a suppressive effect on the neuronal response. The weighting of the component responses was not fixed but dependent on relative signal strengths. When two stimulus components moved at different coherence levels, the response weight for the higher-coherence component was significantly greater than that for the lower-coherence component. We also varied relative luminance levels of two coherently moving stimuli and found that MT response weight for the higher-luminance component was also greater. These results suggest that competition between multiple stimuli within a neuron's RF depends on relative signal strengths of the stimuli and that multiplicative nonlinearity may play an important role in shaping the response tuning for multiple stimuli. PMID:24899674

Innate immunity of fish (overview).

PubMed

Magnadóttir, Bergljót

2006-02-01

The innate immune system is the only defence weapon of invertebrates and a fundamental defence mechanism of fish. The innate system also plays an instructive role in the acquired immune response and homeostasis and is therefore equally important in higher vertebrates. The innate system's recognition of non-self and danger signals is served by a limited number of germ-line encoded pattern recognition receptors/proteins, which recognise pathogen associated molecular patterns like bacterial and fungal glycoproteins and lipopolysaccharides and intracellular components released through injury or infection. The innate immune system is divided into physical barriers, cellular and humoral components. Humoral parameters include growth inhibitors, various lytic enzymes and components of the complement pathways, agglutinins and precipitins (opsonins, primarily lectins), natural antibodies, cytokines, chemokines and antibacterial peptides. Several external and internal factors can influence the activity of innate immune parameters. Temperature changes, handling and crowding stress can have suppressive effects on innate parameters, whereas several food additives and immunostimulants can enhance different innate factors. There is limited data available about the ontogenic development of the innate immunological system in fish. Active phagocytes, complement components and enzyme activity, like lysozyme and cathepsins, are present early in the development, before or soon after hatching.

Commonalities in the central nervous system's involvement with complementary medical therapies: limbic morphinergic processes.

PubMed

Esch, Tobias; Guarna, Massimo; Bianchi, Enrica; Zhu, Wei; Stefano, George B

2004-06-01

Currently, complementary and alternative medicine (CAM) are experiencing growing popularity, especially in former industrialized countries. However, most of the underlying physiological and molecular mechanisms as well as participating biological structures are still speculative. Specific and non-specific effects may play a role in CAM. Moreover, trust, belief, and expectation may be of importance, pointing towards common central nervous system (CNS) pathways involved in CAM. Four CAM approaches (acupuncture, meditation, music therapy, and massage therapy) were examined with regard to the CNS activity pattern involved. CNS commonalities between different approaches were investigated. Frontal/prefrontal and limbic brain structures play a role in CAM. Particularly, left-anterior regions of the brain and reward or motivation circuitry constituents are involved, indicating positive affect and emotion-related memory processing--accompanied by endocrinologic and autonomic functions--as crucial components of CAM effects. Thus, trust and belief in a therapist or positive therapy expectations seem to be important. However, besides common non-specific or subjective effects, specific (objective) physiological components also exist. Non-specific CNS commonalities are involved in various CAM therapies. Different therapeutic approaches physiologically overlap in the brain. However, molecular correspondents of the detected CNS analogies still have to be specified. In particular, fast acting autoregulatory signaling molecules presumably play a role. These may also be involved in the placebo response.

Gauging Disciplinary Engagement with Internationalization: A Survey of Geographers in the United States

ERIC Educational Resources Information Center

Ray, Waverly; Solem, Michael

2009-01-01

As higher education institutions worldwide seek to internationalize academic programmes, questions arise as to how institutions can effectively involve and support faculty in that process. The present study rests on the premise that professional development can play a decisive role in advancing two important components of…

THE ABCS OF SNOWMELT: A TOPOGRAPHICALLY FACTORIZED ENERGY COMPONENT SNOWMELT MODEL. (R824784)

EPA Science Inventory

Because of the crucial role snowmelt plays in many watersheds around the world, it is important to understand and accurately quantify the melt process. As such, numerous mathematical models attempting to describe and predict snowmelt have arisen. There are two main categories of ...

Nitric Oxide Mediates Biofilm Formation and Symbiosis in Silicibacter sp. Strain TrichCH4B.

PubMed

Rao, Minxi; Smith, Brian C; Marletta, Michael A

2015-05-05

Nitric oxide (NO) plays an important signaling role in all domains of life. Many bacteria contain a heme-nitric oxide/oxygen binding (H-NOX) protein that selectively binds NO. These H-NOX proteins often act as sensors that regulate histidine kinase (HK) activity, forming part of a bacterial two-component signaling system that also involves one or more response regulators. In several organisms, NO binding to the H-NOX protein governs bacterial biofilm formation; however, the source of NO exposure for these bacteria is unknown. In mammals, NO is generated by the enzyme nitric oxide synthase (NOS) and signals through binding the H-NOX domain of soluble guanylate cyclase. Recently, several bacterial NOS proteins have also been reported, but the corresponding bacteria do not also encode an H-NOX protein. Here, we report the first characterization of a bacterium that encodes both a NOS and H-NOX, thus resembling the mammalian system capable of both synthesizing and sensing NO. We characterized the NO signaling pathway of the marine alphaproteobacterium Silicibacter sp. strain TrichCH4B, determining that the NOS is activated by an algal symbiont, Trichodesmium erythraeum. NO signaling through a histidine kinase-response regulator two-component signaling pathway results in increased concentrations of cyclic diguanosine monophosphate, a key bacterial second messenger molecule that controls cellular adhesion and biofilm formation. Silicibacter sp. TrichCH4B biofilm formation, activated by T. erythraeum, may be an important mechanism for symbiosis between the two organisms, revealing that NO plays a previously unknown key role in bacterial communication and symbiosis. Bacterial nitric oxide (NO) signaling via heme-nitric oxide/oxygen binding (H-NOX) proteins regulates biofilm formation, playing an important role in protecting bacteria from oxidative stress and other environmental stresses. Biofilms are also an important part of symbiosis, allowing the organism to remain in a nutrient-rich environment. In this study, we show that in Silicibacter sp. strain TrichCH4B, NO mediates symbiosis with the alga Trichodesmium erythraeum, a major marine diazotroph. In addition, Silicibacter sp. TrichCH4B is the first characterized bacteria to harbor both the NOS and H-NOX proteins, making it uniquely capable of both synthesizing and sensing NO, analogous to mammalian NO signaling. Our study expands current understanding of the role of NO in bacterial signaling, providing a novel role for NO in bacterial communication and symbiosis. Copyright © 2015 Rao et al.

Theory and modeling of atmospheric turbulence, part 2

NASA Technical Reports Server (NTRS)

Chen, C. M.

1984-01-01

Two dimensional geostrophic turbulence driven by a random force is investigated. Based on the Liouville equation, which simulates the primitive hydrodynamical equations, a group-kinetic theory of turbulence is developed and the kinetic equation of the scaled singlet distribution is derived. The kinetic equation is transformed into an equation of spectral balance in the equilibrium and non-equilibrium states. Comparison is made between the propagators and the Green's functions in the case of the non-asymptotic quasi-linear equation to prove the equivalence of both kinds of approximations used to describe perturbed trajectories of plasma turbulence. The microdynamical state of fluid turbulence is described by a hydrodynamical system and transformed into a master equation analogous to the Vlasov equation for plasma turbulence. The spectral balance for the velocity fluctuations of individual components shows that the scaled pressure strain correlation and the cascade transfer are two transport functions that play the most important roles.

Multiple communication mechanisms between sensor kinases are crucial for virulence in Pseudomonas aeruginosa.

PubMed

Francis, Vanessa I; Waters, Elaine M; Finton-James, Sutharsan E; Gori, Andrea; Kadioglu, Aras; Brown, Alan R; Porter, Steven L

2018-06-07

Bacteria and many non-metazoan Eukaryotes respond to stresses and threats using two-component systems (TCSs) comprising sensor kinases (SKs) and response regulators (RRs). Multikinase networks, where multiple SKs work together, detect and integrate different signals to control important lifestyle decisions such as sporulation and virulence. Here, we study interactions between two SKs from Pseudomonas aeruginosa, GacS and RetS, which control the switch between acute and chronic virulence. We demonstrate three mechanisms by which RetS attenuates GacS signalling: RetS takes phosphoryl groups from GacS-P; RetS has transmitter phosphatase activity against the receiver domain of GacS-P; and RetS inhibits GacS autophosphorylation. These mechanisms play important roles in vivo and during infection, and exemplify an unprecedented degree of signal processing by SKs that may be exploited in other multikinase networks.

The possible role of human milk nucleotides as sleep inducers.

PubMed

Sánchez, Cristina L; Cubero, Javier; Sánchez, Javier; Chanclón, Belén; Rivero, Montserrat; Rodríguez, Ana B; Barriga, Carmen

2009-02-01

Breast-milk contains a potent mixture of diverse components, such as the non-protein nitrogen fraction which includes nucleotides, whose variation in levels is evident throughout lactation. In addition, these substances play an important role in sleep homeostasis. In the present study, human milk samples were analyzed using a capillary electrophoresis system. The rhythmicity of each nucleotide was studied by cosinor analysis. It was found that the nucleotides 5'AMP, 5'GMP, 5'CMP, and 5'IMP have significant (P < 0.05) circadian rhythms, the acrophases of the first two being during the night, and of the latter two during the day. While 5'UMP did not show a clear circadian rhythm, there was an increase in its levels at night. In conclusion, the rise in nocturnal levels of 5'AMP, 5'GMP, and 5'UMP could be involved in inducing the 'hypnotic' action of breast-milk at night in the infant.

Kinetics of the inhibitory interaction of organophosphorus neuropathy inducers and non-inducers in soluble esterases in the avian nervous system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mangas, Iris; Vilanova, Eugenio; Estevez, Jorge, E-mail: jorge.estevez@umh.es

2011-11-15

Some published studies suggest that low level exposure to organophosphorus esters (OPs) may cause neurological and neurobehavioral effects at long term exposure. These effects cannot be explained by action on known targets. In this work, the interactions (inhibition, spontaneous reactivation and 'ongoing inhibition') of two model OPs (paraoxon, non neuropathy-inducer, and mipafox, neuropathy-inducer) with the chicken brain soluble esterases were evaluated. The best-fitting kinetic model with both inhibitors was compatible with three enzymatic components. The amplitudes (proportions) of the components detected with mipafox were similar to those obtained with paraoxon. These observations confirm the consistency of the results and themore » model applied and may be considered an external validation. The most sensitive component (E{alpha}) for paraoxon (11-23% of activity, I{sub 50} (30 min) = 9-11 nM) is also the most sensitive for mipafox (I{sub 50} (30 min) = 4 nM). This component is spontaneously reactivated after inhibition with paraoxon. The second sensitive component to paraoxon (E{beta}, 71-84% of activity; I{sub 50} (30 min) = 1216 nM) is practically resistant to mipafox. The third component (E{gamma}, 5-8% of activity) is paraoxon resistant and has I{sub 50} (30 min) of 3.4 {mu}M with mipafox, similar to NTE (neuropathy target esterase). The role of these esterases remains unknown. Their high sensitivity suggests that they may either play a role in toxicity in low-level long-term exposure of organophosphate compounds or have a protective effect related with the spontaneous reactivation. They will have to be considered in further metabolic and toxicological studies. -- Research Highlights: Black-Right-Pointing-Pointer Paraoxon and mipafox interactions have been evaluated with chicken soluble brain esterases. Black-Right-Pointing-Pointer The paraoxon inhibition was analyzed considering the simultaneous spontaneous reactivation. Black-Right-Pointing-Pointer The best-fitting kinetic models were compatible with a three enzymatic components. Black-Right-Pointing-Pointer The amplitudes of the components were similar in paraoxon and mipafox experiments. Black-Right-Pointing-Pointer It is suggested they may play a role in toxicity in low-level long-term exposure of these compounds.« less

Durability and CMAS Resistance of Advanced Environmental Barrier Coatings Systems for SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming

2015-01-01

Environmental barrier coatings (EBCs) and SiCSiC ceramic matrix composites (CMCs) systems will play a crucial role in next generation turbine engines for hot-section component applications because of their ability to significantly increase engine operating temperatures with improved efficiency, reduce engine weight and cooling requirements. This paper will emphasize advanced environmental barrier coating developments for SiCSiC turbine airfoil components, by using advanced coating compositions and processing, in conjunction with mechanical and environment testing and durability validations. The coating-CMC degradations and durability in the laboratory simulated engine fatigue-creep and complex operating environments are being addressed. The effects of Calcium-Magnesium-Alumino-Silicate (CMAS) from road sand or volcano-ash deposits on the degradation mechanisms of the environmental barrier coating systems will be discussed. The results help understand the advanced EBC-CMC system performance, aiming at the durability improvements of more robust, prime-reliant environmental barrier coatings for successful applications of the component technologies and lifing methodologies.

Development and Property Evaluation of Selected HfO2-Silicon and Rare Earth-Silicon Based Bond Coats and Environmental Barrier Coating Systems for SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming

2016-01-01

Ceramic environmental barrier coatings (EBC) and SiC/SiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft propulsion systems because of their ability to significantly increase engine operating temperatures, improve component durability, reduce engine weight and cooling requirements. Advanced EBC systems for SiC/SiC CMC turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant material development challenges for the high temperature CMC components is to develop prime-reliant, high strength and high temperature capable environmental barrier coating bond coat systems, since the current silicon bond coat cannot meet the advanced EBC-CMC temperature and stability requirements. In this paper, advanced NASA HfO2-Si and rare earth Si based EBC bond coat EBC systems for SiC/SiC CMC combustor and turbine airfoil applications are investigated. High temperature properties of the advanced EBC systems, including the strength, fracture toughness, creep and oxidation resistance have been studied and summarized. The advanced NASA EBC systems showed some promise to achieve 1500C temperature capability, helping enable next generation turbine engines with significantly improved engine component temperature capability and durability.

Systems engineering at the nanoscale

NASA Astrophysics Data System (ADS)

Benkoski, Jason J.; Breidenich, Jennifer L.; Wei, Michael C.; Clatterbaughi, Guy V.; Keng, Pei Yuin; Pyun, Jeffrey

2012-06-01

Nanomaterials have provided some of the greatest leaps in technology over the past twenty years, but their relatively early stage of maturity presents challenges for their incorporation into engineered systems. Perhaps even more challenging is the fact that the underlying physics at the nanoscale often run counter to our physical intuition. The current state of nanotechnology today includes nanoscale materials and devices developed to function as components of systems, as well as theoretical visions for "nanosystems," which are systems in which all components are based on nanotechnology. Although examples will be given to show that nanomaterials have indeed matured into applications in medical, space, and military systems, no complete nanosystem has yet been realized. This discussion will therefore focus on systems in which nanotechnology plays a central role. Using self-assembled magnetic artificial cilia as an example, we will discuss how systems engineering concepts apply to nanotechnology.

How School Administrators Respond to Teacher Affect

ERIC Educational Resources Information Center

McQuestion, Rebecca J.

2016-01-01

The teacher-student relationship is a vital component to the social, emotional, and academic growth of students. Nationwide the one constant in teachers' classrooms are the observations by administrators. Administrators play a supporting role for students and teachers in our modern educational system. The present case study examined four middle…

Beneficial effects of Houttuynia cordata polysaccharides on "two-hit" acute lung injury and endotoxic fever in rats associated with anti-complementary activities.

PubMed

Lu, Yan; Jiang, Yun; Ling, Lijun; Zhang, Yunyi; Li, Hong; Chen, Daofeng

2018-03-01

Houttuynia cordata Thunb. is a traditional herb used for clearing heat and eliminating toxins, and has also been used for the treatment of severe acute respiratory syndrome (SARS). In vitro, the crude H. cordata polysaccharides (CHCP) exhibited potent anti-complementary activity through both the classical and alternative pathways by acting on components C3 and C4 of the complement system without interfering with the coagulation system. This study was to investigate the preventive effects of CHCP on acute lung injury (ALI) induced by hemorrhagic shock plus lipopolysaccharide (LPS) instillation (two-hit) and LPS-induced fever in rats. CHCP significantly attenuated pulmonary injury in the "two-hit" ALI model by reducing pulmonary edema and protein exudation in bronchoalveolar lavage fluid (BALF). In addition, it reduced the deposit of complement activation products in the lung and improved oxidant-antioxidant imbalance. Moreover, CHCP administration inhibited fever in rats, reduced the number of leukocytes and restored serum complement levels. The inhibition on the inappropriate activation of complement system by CHCP may play an important role in its beneficial effects on inflammatory diseases. The anti-complementary polysaccharides are likely to be among the key substances for the heat-clearing function of H. cordata .

Self-duality of the compactified Ruijsenaars-Schneider system from quasi-Hamiltonian reduction

NASA Astrophysics Data System (ADS)

Fehér, L.; Klimčík, C.

2012-07-01

The Delzant theorem of symplectic topology is used to derive the completely integrable compactified Ruijsenaars-Schneider IIIb system from a quasi-Hamiltonian reduction of the internally fused double SU(n)×SU(n). In particular, the reduced spectral functions depending respectively on the first and second SU(n) factor of the double engender two toric moment maps on the IIIb phase space CP(n-1) that play the roles of action-variables and particle-positions. A suitable central extension of the SL(2,Z) mapping class group of the torus with one boundary component is shown to act on the quasi-Hamiltonian double by automorphisms and, upon reduction, the standard generator S of the mapping class group is proved to descend to the Ruijsenaars self-duality symplectomorphism that exchanges the toric moment maps. We give also two new presentations of this duality map: one as the composition of two Delzant symplectomorphisms and the other as the composition of three Dehn twist symplectomorphisms realized by Goldman twist flows. Through the well-known relation between quasi-Hamiltonian manifolds and moduli spaces, our results rigorously establish the validity of the interpretation [going back to Gorsky and Nekrasov] of the IIIb system in terms of flat SU(n) connections on the one-holed torus.

Few-body resonances of unequal-mass systems with infinite interspecies two-body s-wave scattering length

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blume, D.; Daily, K. M.

Two-component Fermi and Bose gases with infinitely large interspecies s-wave scattering length a{sub s} exhibit a variety of intriguing properties. Among these are the scale invariance of two-component Fermi gases with equal masses, and the favorable scaling of Efimov features for two-component Bose gases and Bose-Fermi mixtures with unequal masses. This paper builds on our earlier work [Phys. Rev. Lett. 105, 170403 (2010)] and presents a detailed discussion of our studies of small unequal-mass two-component systems with infinite a{sub s} in the regime where three-body Efimov physics is absent. We report on nonuniversal few-body resonances. Just like with two-body systemsmore » on resonance, few-body systems have a zero-energy bound state in free space and a diverging generalized scattering length. Our calculations are performed within a nonperturbative microscopic framework and investigate the energetics and structural properties of small unequal-mass two-component systems as functions of the mass ratio {kappa}, and the numbers N{sub 1} and N{sub 2} of heavy and light atoms. For purely attractive Gaussian two-body interactions, we find that the (N{sub 1},N{sub 2})=(2,1) and (3,1) systems exhibit three-body and four-body resonances at mass ratios {kappa}=12.314(2) and 10.4(2), respectively. The three- and four-particle systems on resonance are found to be large. It seems feasible that the features discussed in this paper can be probed experimentally with present-day technology.« less

System and method for detecting cells or components thereof

DOEpatents

Porter, Marc D [Ames, IA; Lipert, Robert J [Ames, IA; Doyle, Robert T [Ames, IA; Grubisha, Desiree S [Corona, CA; Rahman, Salma [Ames, IA

2009-01-06

A system and method for detecting a detectably labeled cell or component thereof in a sample comprising one or more cells or components thereof, at least one cell or component thereof of which is detectably labeled with at least two detectable labels. In one embodiment, the method comprises: (i) introducing the sample into one or more flow cells of a flow cytometer, (ii) irradiating the sample with one or more light sources that are absorbed by the at least two detectable labels, the absorption of which is to be detected, and (iii) detecting simultaneously the absorption of light by the at least two detectable labels on the detectably labeled cell or component thereof with an array of photomultiplier tubes, which are operably linked to two or more filters that selectively transmit detectable emissions from the at least two detectable labels.

Chandler wobble: two more large phase jumps revealed

NASA Astrophysics Data System (ADS)

Malkin, Zinovy; Miller, Natalia

2010-12-01

Investigations of the anomalies in the Earth rotation, in particular, the polar motion components, play an important role in our understanding of the processes that drive changes in the Earth's surface, interior, atmosphere, and ocean. This paper is primarily aimed at investigation of the Chandler wobble (CW) at the whole available 163-year interval to search for the major CW amplitude and phase variations. First, the CW signal was extracted from the IERS (International Earth Rotation and Reference Systems Service) Pole coordinates time series using two digital filters: the singular spectrum analysis and Fourier transform. The CW amplitude and phase variations were examined by means of the wavelet transform and Hilbert transform. Results of our analysis have shown that, besides the well-known CW phase jump in the 1920s, two other large phase jumps have been found in the 1850s and 2000s. As in the 1920s, these phase jumps occurred contemporarily with a sharp decrease in the CW amplitude.

Modular Closed-Loop Control of Diabetes

PubMed Central

Magni, L.; Dassau, E.; Hughes-Karvetski, C.; Toffanin, C.; De Nicolao, G.; Del Favero, S.; Breton, M.; Man, C. Dalla; Renard, E.; Zisser, H.; Doyle, F. J.; Cobelli, C.; Kovatchev, B. P.

2015-01-01

Modularity plays a key role in many engineering systems, allowing for plug-and-play integration of components, enhancing flexibility and adaptability, and facilitating standardization. In the control of diabetes, i.e., the so-called “artificial pancreas,” modularity allows for the step-wise introduction of (and regulatory approval for) algorithmic components, starting with subsystems for assured patient safety and followed by higher layer components that serve to modify the patient’s basal rate in real time. In this paper, we introduce a three-layer modular architecture for the control of diabetes, consisting in a sensor/pump interface module (IM), a continuous safety module (CSM), and a real-time control module (RTCM), which separates the functions of insulin recommendation (postmeal insulin for mitigating hyperglycemia) and safety (prevention of hypoglycemia). In addition, we provide details of instances of all three layers of the architecture: the APS© serving as the IM, the safety supervision module (SSM) serving as the CSM, and the range correction module (RCM) serving as the RTCM. We evaluate the performance of the integrated system via in silico preclinical trials, demonstrating 1) the ability of the SSM to reduce the incidence of hypoglycemia under nonideal operating conditions and 2) the ability of the RCM to reduce glycemic variability. PMID:22481809

Oceanic response to tropical cyclone `Phailin' in the Bay of Bengal

NASA Astrophysics Data System (ADS)

Pant, V.; Prakash, K. R.

2016-02-01

Vertical mixing largely explains surface cooling induced by Tropical Cyclones (TCs). However, TC-induced upwelling of deeper waters plays an important role as it partly balances the warming of subsurface waters induced by vertical mixing. Below 100 m, vertical advection results in cooling that persists for a few days after the storm. The present study investigates the integrated ocean response to tropical cyclone `Phaillin' (10-14 October 2013) in the Bay of Bengal (BoB) through both coupled and stand-alone ocean-atmosphere models. Two numerical experiments with different coupling configurations between Regional Ocean Modelling System (ROMS) and Weather Research and Forecasting (WRF) were performed to investigate the impact of Phailin cyclone on the surface and sub-surface oceanic parameters. In the first experiment, ocean circulation model ROMS observe surface wind forcing from a mesoscale atmospheric model (WRF with nested damin setup), while rest forcing parameters are supplied to ROMS from NCEP data. In the second experiment, all surface forcing data to ROMS directly comes from WRF. The modeling components and data fields exchanged between atmospheric and oceanic models are described. The coupled modeling system is used to identify model sensitivity by exchanging prognostic variable fields between the two model components during simulation of Phallin cyclone (10-14 October 2013) in the BoB.In general, the simulated Phailin cyclone track and intensities agree well with observations in WRF simulations. Further, the inter-comparison between stand-alone and coupled model simulations validated against observations highlights better performance of coupled modeling system in simulating the oceanic conditions during the Phailin cyclone event.

Towards a Multifunctional Electrochemical Sensing and Niosome Generation Lab-on-Chip Platform Based on a Plug-and-Play Concept.

PubMed

Kara, Adnane; Rouillard, Camille; Mathault, Jessy; Boisvert, Martin; Tessier, Frédéric; Landari, Hamza; Melki, Imene; Laprise-Pelletier, Myriam; Boisselier, Elodie; Fortin, Marc-André; Boilard, Eric; Greener, Jesse; Miled, Amine

2016-05-28

In this paper, we present a new modular lab on a chip design for multimodal neurotransmitter (NT) sensing and niosome generation based on a plug-and-play concept. This architecture is a first step toward an automated platform for an automated modulation of neurotransmitter concentration to understand and/or treat neurodegenerative diseases. A modular approach has been adopted in order to handle measurement or drug delivery or both measurement and drug delivery simultaneously. The system is composed of three fully independent modules: three-channel peristaltic micropumping system, a three-channel potentiostat and a multi-unit microfluidic system composed of pseudo-Y and cross-shape channels containing a miniature electrode array. The system was wirelessly controlled by a computer interface. The system is compact, with all the microfluidic and sensing components packaged in a 5 cm × 4 cm × 4 cm box. Applied to serotonin, a linear calibration curve down to 0.125 mM, with a limit of detection of 31 μ M was collected at unfunctionalized electrodes. Added sensitivity and selectivity was achieved by incorporating functionalized electrodes for dopamine sensing. Electrode functionalization was achieved with gold nanoparticles and using DNA and o-phenylene diamine polymer. The as-configured platform is demonstrated as a central component toward an "intelligent" drug delivery system based on a feedback loop to monitor drug delivery.

Towards a Multifunctional Electrochemical Sensing and Niosome Generation Lab-on-Chip Platform Based on a Plug-and-Play Concept

PubMed Central

Kara, Adnane; Rouillard, Camille; Mathault, Jessy; Boisvert, Martin; Tessier, Frédéric; Landari, Hamza; Melki, Imene; Laprise-Pelletier, Myriam; Boisselier, Elodie; Fortin, Marc-André; Boilard, Eric; Greener, Jesse; Miled, Amine

2016-01-01

In this paper, we present a new modular lab on a chip design for multimodal neurotransmitter (NT) sensing and niosome generation based on a plug-and-play concept. This architecture is a first step toward an automated platform for an automated modulation of neurotransmitter concentration to understand and/or treat neurodegenerative diseases. A modular approach has been adopted in order to handle measurement or drug delivery or both measurement and drug delivery simultaneously. The system is composed of three fully independent modules: three-channel peristaltic micropumping system, a three-channel potentiostat and a multi-unit microfluidic system composed of pseudo-Y and cross-shape channels containing a miniature electrode array. The system was wirelessly controlled by a computer interface. The system is compact, with all the microfluidic and sensing components packaged in a 5 cm × 4 cm × 4 cm box. Applied to serotonin, a linear calibration curve down to 0.125 mM, with a limit of detection of 31 μM was collected at unfunctionalized electrodes. Added sensitivity and selectivity was achieved by incorporating functionalized electrodes for dopamine sensing. Electrode functionalization was achieved with gold nanoparticles and using DNA and o-phenylene diamine polymer. The as-configured platform is demonstrated as a central component toward an “intelligent” drug delivery system based on a feedback loop to monitor drug delivery. PMID:27240377

The Escherichia coli BarA-UvrY Two-Component System Is Needed for Efficient Switching between Glycolytic and Gluconeogenic Carbon Sources

PubMed Central

Pernestig, Anna-Karin; Georgellis, Dimitris; Romeo, Tony; Suzuki, Kazushi; Tomenius, Henrik; Normark, Staffan; Melefors, Öjar

2003-01-01

The Escherichia coli BarA and UvrY proteins were recently demonstrated to constitute a novel two-component system, although its function has remained largely elusive. Here we show that mutations in the sensor kinase gene, barA, or the response regulator gene, uvrY, in uropathogenic E. coli drastically affect survival in long-term competition cultures. Using media with gluconeogenic carbon sources, the mutants have a clear growth advantage when competing with the wild type, but using media with carbon sources feeding into the glycolysis leads to a clear growth advantage for the wild type. Results from competitions with mutants in the carbon storage regulation system, CsrA/B, known to be a master switch between glycolysis and gluconeogenesis, led us to propose that the BarA-UvrY two-component system controls the Csr system. Taking these results together, we propose the BarA-UvrY two-component system is crucial for efficient adaptation between different metabolic pathways, an essential function for adaptation to a new environment. PMID:12533459

Chemical characterization of polycyclic aromatic hydrocarbons (PAHs) in 2013 Rayong oil spill-affected coastal areas of Thailand.

PubMed

Pongpiachan, S; Hattayanone, M; Tipmanee, D; Suttinun, O; Khumsup, C; Kittikoon, I; Hirunyatrakul, P

2018-02-01

Among Southeast Asian countries, Thailand has gradually accustomed to extremely prompt urbanization, motorization, and industrialization. Chonburi and Rayong provinces are two provinces involved in "eastern seaboard" industrial zones, which is an emerging economic region that plays a key role in Thailand's economy. The 2013 Rayong oil spill did not only cause damages to the coastal and maritime environment, but also undermine trust in the overall safety system and negatively affect the investor confidence. In this study, 69 coastal soils collected around Koh Samed Island were chemically extracted and analyzed for 15 PAHs by using a Shimadzu GCMS-QP2010 Ultra system comprising a high-speed performance system with ASSP function. In this study, numerous diagnostic binary ratios were applied to identify potential sources of PAHs. Advanced statistical techniques such as hierarchical cluster analysis coupled with principal component analysis were also conducted for further investigations of source identifications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Earth to lunar CELSS evolution

NASA Technical Reports Server (NTRS)

1991-01-01

The comprehensive results of human activities on the environment, such as deforestation and ozone depletion, and the natural laws that govern the global environment have yet to be determined. Closed Ecological Life Support Systems (CELSS) research can play an instrumental role in dispelling these mysteries, as well as have the ability to support life in hostile environments, which the Earth one day may become. CELSS conclusions, such as the timescales in which plants fix carbon dioxide (CO2), will be the key to understanding each component and how it affects the ecological balance between plants and animals, the environment, and the biological engines that drive Earth's system. However, to understand how CELSS can be used as an investigative tool, the concept of a CELSS must be clearly defined. A definition of CELSS is given. The evolutionary establishment of a lunar base with a bioregenerative life support system in a Space Station Freedom (SSF) module to support a crew of four for two weeks duration was chosen as the design topic.

Analytical energy gradient for the two-component normalized elimination of the small component method

NASA Astrophysics Data System (ADS)

Zou, Wenli; Filatov, Michael; Cremer, Dieter

2015-06-01

The analytical gradient for the two-component Normalized Elimination of the Small Component (2c-NESC) method is presented. The 2c-NESC is a Dirac-exact method that employs the exact two-component one-electron Hamiltonian and thus leads to exact Dirac spin-orbit (SO) splittings for one-electron atoms. For many-electron atoms and molecules, the effect of the two-electron SO interaction is modeled by a screened nucleus potential using effective nuclear charges as proposed by Boettger [Phys. Rev. B 62, 7809 (2000)]. The effect of spin-orbit coupling (SOC) on molecular geometries is analyzed utilizing the properties of the frontier orbitals and calculated SO couplings. It is shown that bond lengths can either be lengthened or shortened under the impact of SOC where in the first case the influence of low lying excited states with occupied antibonding orbitals plays a role and in the second case the jj-coupling between occupied antibonding and unoccupied bonding orbitals dominates. In general, the effect of SOC on bond lengths is relatively small (≤5% of the scalar relativistic changes in the bond length). However, large effects are found for van der Waals complexes Hg2 and Cn2, which are due to the admixture of more bonding character to the highest occupied spinors.

Identification and purification of a soluble region of BubR1: a critical component of the mitotic checkpoint complex.

PubMed

Yoon, Jongchul; Kang, Yup; Kim, Kyunggon; Park, Jungeun; Kim, Youngsoo

2005-11-01

The mitotic checkpoint complex (MCC) ensures the fidelity of chromosomal segregation, by delaying the onset of anaphase until all sister chromatids have been properly attached to the mitotic spindle. In essence, this MCC-induced delay is achieved via the inhibition of the anaphase-promoting complex (APC). Among the components of the MCC, BubR1 plays two major roles in the functions of the mitotic checkpoint. First, BubR1 is able to inhibit APC activity, either by itself or as a component of the MCC, by sequestering a APC coactivator, known as Cdc20. Second, BubR1 activates mitotic checkpoint signaling cascades by binding to the centromere-associated protein E, a microtubule motor protein. Obtaining highly soluble BubR1 is a prerequisite for the study of its structure. BubR1 is a multi-domain protein, which includes a KEN box motif, a mad3-like region, a Bub3 binding domain, and a kinase domain. We obtained a soluble BubR1 construct using a three-step expression strategy. First, we obtained two constructs from BLAST sequence homology searches, both of which were expressed abundantly in the inclusion bodies. We then adjusted the lengths of the two constructs by secondary structure prediction, thereby generating partially soluble constructs. Third, we optimized the solubility of the two constructs by either chopping or adding a few residues at the C-terminus. Finally, we obtained a highly soluble BubR1 construct via the Escherichia coli expression system, which allowed for a yield of 10.8 mg/L culture. This report may provide insight into the design of highly soluble constructs of insoluble multi-domain proteins.

Enhancing reading performance through action video games: the role of visual attention span.

PubMed

Antzaka, A; Lallier, M; Meyer, S; Diard, J; Carreiras, M; Valdois, S

2017-11-06

Recent studies reported that Action Video Game-AVG training improves not only certain attentional components, but also reading fluency in children with dyslexia. We aimed to investigate the shared attentional components of AVG playing and reading, by studying whether the Visual Attention (VA) span, a component of visual attention that has previously been linked to both reading development and dyslexia, is improved in frequent players of AVGs. Thirty-six French fluent adult readers, matched on chronological age and text reading proficiency, composed two groups: frequent AVG players and non-players. Participants performed behavioural tasks measuring the VA span, and a challenging reading task (reading of briefly presented pseudo-words). AVG players performed better on both tasks and performance on these tasks was correlated. These results further support the transfer of the attentional benefits of playing AVGs to reading, and indicate that the VA span could be a core component mediating this transfer. The correlation between VA span and pseudo-word reading also supports the involvement of VA span even in adult reading. Future studies could combine VA span training with defining features of AVGs, in order to build a new generation of remediation software.

ISEE observations of low frequency waves and ion distribution function evolution in the plasma sheet boundary layer

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Gary, S. P.

1990-01-01

This paper describes ISEE plasma and magnetic fluctuation observations during two crossings of the plasma sheet boundary layer (PSBL) in the earth's magnetotail. Distribution function observations show that the counterstreaming ion components undergo pitch-angle scattering and evolve into a shell distribution in velocity space. This evolution is correlated with the development of low frequency, low amplitude magnetic fluctuations. However, the measured wave amplitudes are insufficient to accomplish the observed degree of ion pitch-angle scatttering locally; the near-earth distributions may be the result of processes occurring much farther down the magnetotail. Results show a clear correlation between the ion component beta and the relative streaming speed of the two components, suggesting that electromagnetic ion/ion instabilities do play an important role in the scattering of PSBL ions.

A revised HRD for individual components of binary systems from BaSeL BVRI synthetic photometry. Influence of interstellar extinction and stellar rotation

NASA Astrophysics Data System (ADS)

Lastennet, E.; Fernandes, J.; Lejeune, Th.

2002-06-01

Johnson BVRI photometric data for individual components of binary systems have been provided by ten Brummelaar et al. (\\cite{Brummelaar}). This is essential because non-interacting binaries can be considered as two single stars and therefore play a critical role in testing and calibrating single-star stellar evolution sets of isochrones and the implicit theory. While they derived the effective temperature (T_eff) from their estimated spectral type, we infer metallicity-dependent T_eff from a minimizing method fitting the B-V, V-R and V-I colours. For this purpose, a grid of 621 600 flux distributions were computed from the Basel Stellar Library (BaSeL 2.2) of model-atmosphere spectra, and their theoretical colours compared with the observed photometry. The BaSeL colours show a very good agreement with the BVRI metallicity-dependent empirical calibrations of Alonso et al. (\\cite{Alonso}), with the temperatures being different by 3+/-3% in the range 4000-8000 K for dwarf stars. Before deriving the metallicity-dependent T_eff from the BaSeL models, we paid particular attention to the influence of reddening and stellar rotation. We inferred the reddening from two different methods: (i) the MExcessNg code v1.1 (Méndez & van Altena \\cite{Mendez}) and (ii) neutral hydrogen column density data. A comparison of both methods shows a good agreement for the sample located inside a local sphere of ~ 500 pc, but we point out a few directions where the MExcess model overestimates the E(B-V) colour excess. Influence of stellar rotation on the BVRI colours can be neglected except for 5 stars with large v sin i, the maximum effect on temperature being less than 5%. Our final determinations provide effective temperature estimates for each component. They are in good agreement with previous spectroscopic determinations available for a few primary components, and with ten Brummelaar et al. below ~ 10 000 K. Nevertheless, we obtain an increasing disagreement with their temperatures beyond 10 000 K. Finally, we provide a revised Hertzsprung-Russell diagram (HRD) for the systems with the more accurately determined temperatures.

Promoting tissue regeneration by modulating the immune system.

PubMed

Julier, Ziad; Park, Anthony J; Briquez, Priscilla S; Martino, Mikaël M

2017-04-15

The immune system plays a central role in tissue repair and regeneration. Indeed, the immune response to tissue injury is crucial in determining the speed and the outcome of the healing process, including the extent of scarring and the restoration of organ function. Therefore, controlling immune components via biomaterials and drug delivery systems is becoming an attractive approach in regenerative medicine, since therapies based on stem cells and growth factors have not yet proven to be broadly effective in the clinic. To integrate the immune system into regenerative strategies, one of the first challenges is to understand the precise functions of the different immune components during the tissue healing process. While remarkable progress has been made, the immune mechanisms involved are still elusive, and there is indication for both negative and positive roles depending on the tissue type or organ and life stage. It is well recognized that the innate immune response comprising danger signals, neutrophils and macrophages modulates tissue healing. In addition, it is becoming evident that the adaptive immune response, in particular T cell subset activities, plays a critical role. In this review, we first present an overview of the basic immune mechanisms involved in tissue repair and regeneration. Then, we highlight various approaches based on biomaterials and drug delivery systems that aim at modulating these mechanisms to limit fibrosis and promote regeneration. We propose that the next generation of regenerative therapies may evolve from typical biomaterial-, stem cell-, or growth factor-centric approaches to an immune-centric approach. Most regenerative strategies have not yet proven to be safe or reasonably efficient in the clinic. In addition to stem cells and growth factors, the immune system plays a crucial role in the tissue healing process. Here, we propose that controlling the immune-mediated mechanisms of tissue repair and regeneration may support existing regenerative strategies or could be an alternative to using stem cells and growth factors. The first part of this review we highlight key immune mechanisms involved in the tissue healing process and marks them as potential target for designing regenerative strategies. In the second part, we discuss various approaches using biomaterials and drug delivery systems that aim at modulating the components of the immune system to promote tissue regeneration. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Co-culture-inducible bacteriocin production in lactic acid bacteria.

PubMed

Chanos, Panagiotis; Mygind, Tina

2016-05-01

It is common knowledge that microorganisms have capabilities, like the production of antimicrobial compounds, which do not normally appear in ideal laboratory conditions. Common antimicrobial discovery techniques require the isolation of monocultures and their individual screening against target microorganisms. One strategy to achieve expression of otherwise hidden antimicrobials is induction by co-cultures. In the area of bacteriocin-producing lactic acid bacteria, there has been some research focusing into the characteristics of co-culture-inducible bacteriocin production and particularly the molecular mechanism(s) of such interactions. No clear relationship has been seen between bacteriocin-inducing and bacteriocin-producing microorganisms. The three-component regulatory system seems to be playing a central role in the induction, but inducing compounds have not been identified or characterized. However, the presence of the universal messenger molecule autoinducer-2 has been associated in some cases with the co-culture-inducible bacteriocin phenotype and it may play the role in the additional regulation of the three-component regulatory system. Understanding the mechanisms of induction would facilitate the development of strategies for screening and development of co-culture bacteriocin-producing systems and novel products as well as the perseverance of such systems in food and down to the intestinal tract, possibly conferring a probiotic effect on the host.

Ecological Relationships Between Components in Closed Aquatic Ecosystems

NASA Astrophysics Data System (ADS)

Pisman, Tamara; Somova, Lydia

The work considers the problems of relationships between algae and other microorganisms in aquatic ecosystems. Using small-scale laboratory "autotroph-heterotroph" ecosystems with different types of closure, we showed the results of the investigation into the ecological relation-ships of algae in biocenoses. The autotrophic component was represented by green microalgae, and the heterotrophic component -by yeast and bacteria. An important role in functioning of algobacterial communities is played by 2 -2 (oxygen -carbon dioxide) exchange. The gas exchange between algae and yeast was studied in the "autotroph-heterotroph" gas-closed ecosystem with space-divided components. It was shown that the gas exchange closure of the components into a system prolongs its existence. Hav-ing increased the degree of the system closure by introducing two yeast species with positive metabolic interaction to the heterotrophic component, we observed a significant increase in the gas exchange between the components and thus in the biomass of algae and yeast. The most ancient and ecologically relevant symbioses known in nature are symbiotic associa-tions of algae and heterotrophic organisms. The main symbionts of algae in aquatic ecosystems are bacteria. The cenosis-forming role of algae is based on two characteristics: firstly, their mucous covers and membranes are able to absorb and retain large amounts of water; secondly, many algae evolve various organic substances during their lifetime. An example of algobacterial associations are microalgae Chlorella vulgaris and accompanying microbial flora. Experiments with non-sterile batch culture of algae showed that the increase in the algae biomass was accompanied by the increase in the bacterial biomass. As a result of theoretical and experi-mental investigation into their relationships, it was shown that the largest biomass of bacteria is achieved when using organic substances evolved by algae and having bacteria grow on dead algae; i.e. bacteria can also act as decomposers. It was demonstrated that the cenosis-forming role of algae and bacteria in an algobacterial cenosis is determined by accumulation of both organic matter and nitrogen which is included into the cycle of matter. Thus, the process of C-compound evolution by algae in an algobacterial cenosis is strongly connected with the process of consumption of these compounds by corresponding bacteria, which, in their turn, ensure photosynthesis and algae development by evolving 2 and nitrogen.

Parkinson disease: a role for autophagy?

PubMed

Yang, Qian; Mao, Zixu

2010-08-01

Autophagy is a term used to describe the process by which lysosomes degrade intracellular components. Known originally as an adaptive response to nutrient deprivation, autophagy has now been recognized to play important roles in several human disorders including neurodegenerative diseases. Experimental results from genetic, cellular, and toxicological studies indicate that many of the etiological factors associated with Parkinson disease (PD) can perturb the autophagic process in various model systems. Thus, the emerging data support the view that dysregulation of autophagy may play a critical role in the pathogenic process of PD.

What can volunteer co-providers contribute to health systems? The role of people living with HIV in the Thai paediatric HIV programme.

PubMed

Tulloch, Olivia; Taegtmeyer, Miriam; Ananworanich, Jintanat; Chasombat, Sanchai; Kosalaraksa, Pope; Theobald, Sally

2015-11-01

In Thailand people living with HIV (PLHIV) have played a major role in shaping policy and practice. They have acted as volunteer co-providers, although their potential in terms of paediatric service provision has seldom been explored from a health systems perspective. We describe the Thai paediatric HIV care system and use both demand- and supply-side perspectives to explore the impact, opportunities and challenges of PLHIV acting as volunteer co-providers. We employed qualitative methods to assess experiences and perceptions and triangulate stakeholder perspectives. Data were collected in Khon Kaen province, in the poorest Northeastern region of Thailand: three focus group discussions and two workshops (total participants n = 31) with co-providers and hospital staff; interviews with ART service-users (n = 35). Nationally, key informant interviews were conducted with policy actors (n = 20). Volunteer co-providers were found to be ideally placed to broker the link between clinic and communities for HIV infected children and played an important part in the vital psychosocial support component of HIV care. As co-providers they were recognized as having multiple roles linking and delivering services in clinics and communities. Clear emerging needs include strengthened coordination and training as well as strategies to support funding. Using motivated volunteers with a shared HIV status as co-providers for specific clinical services can contribute to strengthening health systems in Asia; they are critical players in delivering care (supply side) and being responsive to service-users needs (demand side). Co-providers blur the boundaries between these two spheres. Sustaining and optimising co-providers' contribution to health systems strengthening requires a health systems approach. Our findings help to guide policy makers and service providers on how to balance clinical priorities with psycho-social responsiveness and on how best to integrate the views and experience of volunteers into a holistic model of care. Copyright © 2014 Elsevier Ltd. All rights reserved.

Satellite Attitude Control Utilizing the Earth's Magnetic Field

NASA Technical Reports Server (NTRS)

White, John S.; Shigemoto, Fred H.; Bourquin, Kent

1961-01-01

A study was conducted to determine the feasibility of a satellite attitude fine-control system using the interaction of the earth's magnetic field with current-carrying coils to produce torque. The approximate intensity of the earth's magnetic field was determined as a function of the satellite coordinates. Components of the magnetic field were found to vary essentially sinusoidally at approximately twice orbital frequency. Amplitude and distortion of the sinusoidal components were a function of satellite orbit. Two systems for two-axis attitude control evolved from this study, one using three coils and the other using two coils. The torques developed by the two systems differ only when the component of magnetic field along the tracking line is zero. For this case the two-coil system develops no torque whereas the three-coil system develops some effective torque which allows partial control. The equations which describe the three-coil system are complex in comparison to those of the two-coil system and require the measurement of all three components of the magnetic field as compared with only one for the two-coil case. Intermittent three-axis torquing can also be achieved. This torquing can be used for coarse attitude control, or for dumping the stored momentum of inertia reaction wheels. Such a system has the advantage of requiring no fuel aboard the satellite. For any of these magnetic torquing schemes the power required to produce the magnetic moment and the weight of the coil seem reasonable.

454 Transcriptome sequencing suggests a role for two-component signalling in cellularization and differentiation of barley endosperm transfer cells.

PubMed

Thiel, Johannes; Hollmann, Julien; Rutten, Twan; Weber, Hans; Scholz, Uwe; Weschke, Winfriede

2012-01-01

Cell specification and differentiation in the endosperm of cereals starts at the maternal-filial boundary and generates the endosperm transfer cells (ETCs). Besides the importance in assimilate transfer, ETCs are proposed to play an essential role in the regulation of endosperm differentiation by affecting development of proximate endosperm tissues. We attempted to identify signalling elements involved in early endosperm differentiation by using a combination of laser-assisted microdissection and 454 transcriptome sequencing. 454 sequencing of the differentiating ETC region from the syncytial state until functionality in transfer processes captured a high proportion of novel transcripts which are not available in existing barley EST databases. Intriguingly, the ETC-transcriptome showed a high abundance of elements of the two-component signalling (TCS) system suggesting an outstanding role in ETC differentiation. All components and subfamilies of the TCS, including distinct kinds of membrane-bound receptors, have been identified to be expressed in ETCs. The TCS system represents an ancient signal transduction system firstly discovered in bacteria and has previously been shown to be co-opted by eukaryotes, like fungi and plants, whereas in animals and humans this signalling route does not exist. Transcript profiling of TCS elements by qRT-PCR suggested pivotal roles for specific phosphorelays activated in a coordinated time flow during ETC cellularization and differentiation. ETC-specificity of transcriptionally activated TCS phosphorelays was assessed for early differentiation and cellularization contrasting to an extension of expression to other grain tissues at the beginning of ETC maturation. Features of candidate genes of distinct phosphorelays and transcriptional activation of genes putatively implicated in hormone signalling pathways hint at a crosstalk of hormonal influences, putatively ABA and ethylene, and TCS signalling. Our findings suggest an integral function for the TCS in ETC differentiation possibly coupled to sequent hormonal regulation by ABA and ethylene.

454 Transcriptome Sequencing Suggests a Role for Two-Component Signalling in Cellularization and Differentiation of Barley Endosperm Transfer Cells

PubMed Central

Thiel, Johannes; Hollmann, Julien; Rutten, Twan; Weber, Hans; Scholz, Uwe; Weschke, Winfriede

2012-01-01

Background Cell specification and differentiation in the endosperm of cereals starts at the maternal-filial boundary and generates the endosperm transfer cells (ETCs). Besides the importance in assimilate transfer, ETCs are proposed to play an essential role in the regulation of endosperm differentiation by affecting development of proximate endosperm tissues. We attempted to identify signalling elements involved in early endosperm differentiation by using a combination of laser-assisted microdissection and 454 transcriptome sequencing. Principal Findings 454 sequencing of the differentiating ETC region from the syncytial state until functionality in transfer processes captured a high proportion of novel transcripts which are not available in existing barley EST databases. Intriguingly, the ETC-transcriptome showed a high abundance of elements of the two-component signalling (TCS) system suggesting an outstanding role in ETC differentiation. All components and subfamilies of the TCS, including distinct kinds of membrane-bound receptors, have been identified to be expressed in ETCs. The TCS system represents an ancient signal transduction system firstly discovered in bacteria and has previously been shown to be co-opted by eukaryotes, like fungi and plants, whereas in animals and humans this signalling route does not exist. Transcript profiling of TCS elements by qRT-PCR suggested pivotal roles for specific phosphorelays activated in a coordinated time flow during ETC cellularization and differentiation. ETC-specificity of transcriptionally activated TCS phosphorelays was assessed for early differentiation and cellularization contrasting to an extension of expression to other grain tissues at the beginning of ETC maturation. Features of candidate genes of distinct phosphorelays and transcriptional activation of genes putatively implicated in hormone signalling pathways hint at a crosstalk of hormonal influences, putatively ABA and ethylene, and TCS signalling. Significance Our findings suggest an integral function for the TCS in ETC differentiation possibly coupled to sequent hormonal regulation by ABA and ethylene. PMID:22848641

Research gaps and technology needs in development of PHM for passive AdvSMR components

NASA Astrophysics Data System (ADS)

Meyer, Ryan M.; Ramuhalli, Pradeep; Coble, Jamie B.; Hirt, Evelyn H.; Mitchell, Mark R.; Wootan, David W.; Berglin, Eric J.; Bond, Leonard J.; Henagar, Chuck H., Jr.

2014-02-01

Advanced small modular reactors (AdvSMRs), which are based on modularization of advanced reactor concepts, may provide a longer-term alternative to traditional light-water reactors and near-term small modular reactors (SMRs), which are based on integral pressurized water reactor (iPWR) concepts. SMRs are challenged economically because of losses in economy of scale; thus, there is increased motivation to reduce the controllable operations and maintenance costs through automation technologies including prognostics health management (PHM) systems. In this regard, PHM systems have the potential to play a vital role in supporting the deployment of AdvSMRs and face several unique challenges with respect to implementation for passive AdvSMR components. This paper presents a summary of a research gaps and technical needs assessment performed for implementation of PHM for passive AdvSMR components.

Remote health monitoring system for detecting cardiac disorders.

PubMed

Bansal, Ayush; Kumar, Sunil; Bajpai, Anurag; Tiwari, Vijay N; Nayak, Mithun; Venkatesan, Shankar; Narayanan, Rangavittal

2015-12-01

Remote health monitoring system with clinical decision support system as a key component could potentially quicken the response of medical specialists to critical health emergencies experienced by their patients. A monitoring system, specifically designed for cardiac care with electrocardiogram (ECG) signal analysis as the core diagnostic technique, could play a vital role in early detection of a wide range of cardiac ailments, from a simple arrhythmia to life threatening conditions such as myocardial infarction. The system that the authors have developed consists of three major components, namely, (a) mobile gateway, deployed on patient's mobile device, that receives 12-lead ECG signals from any ECG sensor, (b) remote server component that hosts algorithms for accurate annotation and analysis of the ECG signal and (c) point of care device of the doctor to receive a diagnostic report from the server based on the analysis of ECG signals. In the present study, their focus has been toward developing a system capable of detecting critical cardiac events well in advance using an advanced remote monitoring system. A system of this kind is expected to have applications ranging from tracking wellness/fitness to detection of symptoms leading to fatal cardiac events.

The biological component of the life support system for a Martian expedition.

PubMed

Sychev, V N; Levinskikh, M A; Shepelev, Ye Ya

2003-01-01

Ground-based experiments at RF SSC-IBMP RAS (State Science Center of Russian Federation--Institute of Biomedical Problems of Russian Academia of Science) were aimed at overall studies of a human-unicellular algae-mineralization LSS (life support system) model. The system was 15 m3 in volume. It contained 45 L of algal suspension with a dry substance density of 10-12 g per liter; water volume, including the algal suspension, was 59 L. More sophisticated model systems with partial substitution of unicellular algae with higher plates (crop area of 15 m2) were tested in three experiments from 1.5 to 2 months in duration. The experiments demonstrated that LSS employing the unicellular algae play not only a macrofunction (regeneration of atmosphere and water) but also carry some other functions (purification of atmosphere, formation of microbial cenosis etc.) providing an adequate human environment. It is also important that functional reliability of the algal regenerative subsystem is secured by a huge number of cells able, in the event of death of a part of population, to recover in the shortest possible time the size of population and, hence, functionality of the LSS autotrophic component. For a long period of time a Martian crew will be detached from Earth's biosphere and for this reason LSS of their vehicle must be highly reliable, robust and redundant. One of the approaches to LSS redundancy is installation of two systems with different but equally efficient regeneration technologies, i.e. physical-chemical and biological. At best, these two systems should operate in parallel sharing the function of regeneration of the human environment. In case of failure or a sharp deterioration in performance of one system the other will, by way of redundancy, increase its throughput to make up for the loss. This LSS design will enable simultaneous handling of a number of critical problems including adequate satisfaction of human environmental needs. c2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

The Development of Environmental Barrier Coatings for SiCSiC Ceramic Matrix Composites: Challenges and Opportunities

NASA Technical Reports Server (NTRS)

Zhu, Dongming

2014-01-01

Environmental barrier coatings (EBCs) and SiC/SiC ceramic matrix composites (CMCs) systems will play a crucial role in future turbine engines for hot-section component applications because of their ability to significantly increase engine operating temperatures, reduce engine weight and cooling requirements. The development of prime-reliant environmental barrier coatings is a key to enable the applications of the envisioned CMC components to help achieve next generation engine performance and durability goals. This paper will primarily address the performance requirements and design considerations of environmental barrier coatings for turbine engine applications. The emphasis is placed on current candidate environmental barrier coating systems for SiCSiC CMCs, their performance benefits and design limitations in long-term operation and combustion environments. Major technical barriers in developing advanced environmental barrier coating systems, the coating integrations with next generation CMC turbine components having improved environmental stability, cyclic durability and system performance will be described. The development trends for turbine environmental barrier coating systems by utilizing improved compositions, state-of-the-art processing methods, and simulated environment testing and durability modeling will be discussed.

Indigenous Peoples Involment At The Environmental Impact Assessment (EIA) Process in Tabi Mamta Area Of Papua Province

NASA Astrophysics Data System (ADS)

Dhiksawan, Ferdinand Saras; Hadi, Sudharto P.; Samekto, Adji; Sasongko, Dwi P.

2018-02-01

The purpose of this study is to find a picture of the involvement of Indigenous Peoples of Tabi Mamta in the process of environmental impact assessment (EIA) in Tabi Mamta customary territory. The method and type of research used is non-ethnographic qualitative research with data collection techniques using limited observation techniques. Data and information in the field will be analyzed using constructivism paradigm. The paradigm of constructivism is based on an interpretive understanding called hermeneutics (hermeneuien) in the sense of interpreting, giving understanding, translating data and information obtained in the research location as a result of social reality. The results of this study indicate that the customary community of Tabi Mamta is a unit of customary community that still has territorial customary territory, has a customary leadership structure, still visible relationship of kinship, cultural values as well as customary norms and sanctions, and has environmental wisdom in maintaining existence Natural resources. In the socio-cultural system of customary communities there are components such as customary stratification, permissiveness, communication, reciprocity, past history, cultural values, customary norms and sanctions, religious and customary leadership. Components in the socio-cultural system of indigenous and tribal peoples play a role in the EIA process in the Tabi Mamta customary area especially in the environmental feasibility decision making process. The components of custom stratification, cultural values and customary norms play a role in the EIA process. In customary stratification there is uncustomary structure in the ondoafi, Iram and Tribal Leadership. Components in a sociual cultural system is a unity resulting from interaction between individuals and groups to prevent environmental damage and disturbance of natural resources. Natural resources are considered as ancestral symbols passed down by ancestors from generation to generation

Evolution of complement as an effector system in innate and adaptive immunity.

PubMed

Sunyer, J Oriol; Boshra, Hani; Lorenzo, Gema; Parra, David; Freedman, Bruce; Bosch, Nina

2003-01-01

For a long time, the complement system in mammals has been regarded as a biological system that plays an essential role in innate immunity. More recently, it has been recognized that the complement system contributes heavily to the generation and development of an acquired immune response. In fact, this ancient mechanism of defense has evolved from a primitive mechanism of innate immune recognition in invertebrate species to that of an effector system that bridges the innate with the adaptive immune response in vertebrate species. When and how did complement evolve into a shared effector system between innate and adaptive immunity? To answer this question, our group is interested in understanding the role of complement in innate and adaptive immune responses in an evolutionary relevant species: the teleost fish. The attractiveness of this species as an animal model is based on two important facts. First, teleost fish are one of the oldest animal species to have developed an adaptive immune response. Second, the complement system of teleost fish offers a unique feature, which is the structural and functional diversity of its main effector protein, C3, the third component of the complement system.

Children's Comprehension of Live Theatre.

ERIC Educational Resources Information Center

Klein, Jeanne; Fitch, Marguerite

Two studies investigate the way in which children make sense of a play and the visual, aural, and psychological components of theatre which contribute to this comprehension. In the first study, 32 fifth graders saw "Don Quixote of La Mancha." In the second study, 45 third graders saw "Monkey, Monkey" (about the Chinese Monkey King). The day after…

Comparison of three-dimensional orthodontic load systems of different commercial archwires for space closure.

PubMed

Gajda, Steven; Chen, Jie

2012-03-01

To experimentally quantify the effects of the loop design on three-dimensional orthodontic load systems of two types of commercial closing loop archwires: Teardrop and Keyhole. An orthodontic force tester and custom-made dentoform were used to measure the load systems produced on two teeth during simulated space closure. The system included three force components along and three moment components about three clinically defined axes on two target teeth: the left maxillary canine and the lateral incisor. The archwires were attached to the dentoform and were activated following a standard clinical procedure. The resulting six load components produced by the two archwires were reported and compared. The results were also compared with those of the T-loop archwire published previously. The three designs deliver similar loading patterns; however, the component magnitudes are dependent on the design. All of the designs result in lingual tipping of the teeth, canine lingual-mesial displacement, canine crown-mesial-in rotation, and incisor crown-distal-in rotation.

Weighted Components of i-Government Enterprise Architecture

NASA Astrophysics Data System (ADS)

Budiardjo, E. K.; Firmansyah, G.; Hasibuan, Z. A.

2017-01-01

Lack of government performance, among others due to the lack of coordination and communication among government agencies. Whilst, Enterprise Architecture (EA) in the government can be use as a strategic planning tool to improve productivity, efficiency, and effectivity. However, the existence components of Government Enterprise Architecture (GEA) do not show level of importance, that cause difficulty in implementing good e-government for good governance. This study is to explore the weight of GEA components using Principal Component Analysis (PCA) in order to discovered an inherent structure of e-government. The results show that IT governance component of GEA play a major role in the GEA. The rest of components that consist of e-government system, e-government regulation, e-government management, and application key operational, contributed more or less the same. Beside that GEA from other countries analyzes using comparative base on comon enterprise architecture component. These weighted components use to construct i-Government enterprise architecture. and show the relative importance of component in order to established priorities in developing e-government.

Thermal design of spacecraft solar arrays using a polyimide foam

NASA Astrophysics Data System (ADS)

Bianco, N.; Iasiello, M.; Naso, V.

2015-11-01

The design of the Thermal Control System (TCS) of spacecraft solar arrays plays a fundamental role. Indeed, the spacecraft components must operate within a certain range of temperature. If this doesn't occur, their performance is reduced and they may even break. Solar arrays, which are employed to recharge batteries, are directly exposed to the solar heat flux, and they need to be insulated from the earth's surface irradiation. Insulation is currently provided either with a white paint coating or with a Multi Layer Insulation (MLI) system [1]. A configuration based on an open-cell polyimide foam has also been recently proposed [2]. Using polyimide foams in TCSs looks very attractive in terms of costs, weight and assembling. An innovative thermal analysis of the above cited TCS configurations is carried out in this paper, by solving the porous media energy equation, under the assumption of Local Thermal Equilibrium (LTE) between the two phases. Radiation effects through the solar array are also considered by using the Rosseland approximation. Under a stationary daylight condition, temperature profiles are obtained by means of the finite-element based code COMSOL Multiphysics®. Finally, since the weight plays an important role in aerospace applications, weights of the three TCS configurations are compared.

The Two-Phase, Two-Velocity Ionized Absorber in the Seyfert 1 Galaxy NGC 5548

NASA Astrophysics Data System (ADS)

Andrade-Velázquez, Mercedes; Krongold, Yair; Elvis, Martin; Nicastro, Fabrizio; Brickhouse, Nancy; Binette, Luc; Mathur, Smita; Jiménez-Bailón, Elena

2010-03-01

We present an analysis of X-ray high-quality grating spectra of the Seyfert 1 galaxy NGC 5548 using archival Chandra-High Energy Transmission Grating Spectrometer and Low Energy Transmission Grating Spectrometer observations for a total exposure time of 800 ks. The continuum emission (between 0.2 keV and 8 keV) is well represented by a power law (Γ = 1.6) plus a blackbody component (kT = 0.1 keV). We find that the well-known X-ray warm absorber (WA) in this source consists of two different outflow velocity systems. One absorbing system has a velocity of -1110 ± 150 km s-1 and the other of -490 ± 150 km s-1. Recognizing the presence of these kinematically distinct components allows each system to be fitted independently, each with two absorption components with different ionization levels. The high-velocity system consists of two components, one with a temperature of 2.7 ± 0.6 × 106 K, log U = 1.23, and another with a temperature of 5.8 ± 1.0 × 105 K, log U = 0.67. The high-velocity, high-ionization component produces absorption by charge states Fe XXI-XXIV, while the high-velocity, low-ionization component produces absorption by Ne IX-X, Fe XVII-XX, and O VII-VIII. The low-velocity system also required two absorbing components, one with a temperature of 5.8 ± 0.8 × 105 K, log U = 0.67, producing absorption by Ne IX-X, Fe XVII-XX, and O VII-VIII, and the other with a lower temperature of 3.5 ± 0.35 × 104 K and a lower ionization of log U = -0.49, producing absorption by O VI-VII and the Fe VII-XII M-shell Unresolved Transitions Array. Once these components are considered, the data do not require any further absorbers. In particular, a model consisting of a continuous radial range of ionization structures (as suggested by a previous analysis) is not required. The two absorbing components in each velocity system are in pressure equilibrium with each other. This suggests that each velocity system consists of a multi-phase medium. This is the first time that different outflow velocity systems have been modeled independently in the X-ray band for this source. The kinematic components and column densities found from the X-rays are in agreement with the main kinematic components found in the UV absorber. This supports the idea that the UV and X-ray absorbing gas is part of the same phenomenon. NGC 5548 can now be seen to fit in a pattern established for other WAs: two or three discrete phases in pressure equilibrium. There are no remaining cases of a well-studied WA in which a model consisting of a multi-phase medium is not viable.

Robustness of Flexible Systems With Component-Level Uncertainties

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.

2000-01-01

Robustness of flexible systems in the presence of model uncertainties at the component level is considered. Specifically, an approach for formulating robustness of flexible systems in the presence of frequency and damping uncertainties at the component level is presented. The synthesis of the components is based on a modifications of a controls-based algorithm for component mode synthesis. The formulation deals first with robustness of synthesized flexible systems. It is then extended to deal with global (non-synthesized ) dynamic models with component-level uncertainties by projecting uncertainties from component levels to system level. A numerical example involving a two-dimensional simulated docking problem is worked out to demonstrate the feasibility of the proposed approach.

Cover cropping frequency is the main driver of soil microbial changes during six years of organic vegetable production

USDA-ARS?s Scientific Manuscript database

Soil microbes play a key role in soil health, and understanding the functional role of this living component of soil organic matter is critical to developing sustainable systems in major vegetable production regions like Salinas, California. Soil microbial community size and composition was evaluat...

Plant fluid proteomics: Delving into the xylem sap, phloem sap and apoplastic fluid proteomes

USDA-ARS?s Scientific Manuscript database

The phloem sap, xylem sap and apoplastic fluid play key roles in long and short distance transport of signals and nutrients, and act as a barrier against local and systemic pathogen infection. Among other components, these plant fluids contain proteins which are likely to be important players in the...

Online Series presents Cancer Prevention Through Immunomodulation. Does Diet Play a Role? | Division of Cancer Prevention

Cancer.gov

Scientists are increasingly harnessing the power of the immune system to prevent cancer. Nutrition provides an opportunity for a generalized immune activation and reduction of cancer risk in certain populations. Research on several foods and bioactive food components as immunologic modulators is showing promising results. |

Plant fluid proteomics: Delving into the xylem sap, phloem sap and apoplastic fluid proteomes

USDA-ARS?s Scientific Manuscript database

The phloem sap, xylem sap and apoplastic fluid play key roles in long and short distance transport of signals and nutrients, and act as a barrier against local and systemic pathogen infection. Among other components, these plant fluids contain proteins, which are likely to be important players in th...

A Core Plug and Play Architecture for Reusable Flight Software Systems

NASA Technical Reports Server (NTRS)

Wilmot, Jonathan

2006-01-01

The Flight Software Branch, at Goddard Space Flight Center (GSFC), has been working on a run-time approach to facilitate a formal software reuse process. The reuse process is designed to enable rapid development and integration of high-quality software systems and to more accurately predict development costs and schedule. Previous reuse practices have been somewhat successful when the same teams are moved from project to project. But this typically requires taking the software system in an all-or-nothing approach where useful components cannot be easily extracted from the whole. As a result, the system is less flexible and scalable with limited applicability to new projects. This paper will focus on the rationale behind, and implementation of the run-time executive. This executive is the core for the component-based flight software commonality and reuse process adopted at Goddard.

On Some Troubles with the Metaphysics of Fermionic Compositions

NASA Astrophysics Data System (ADS)

Bigaj, Tomasz

2016-09-01

In this paper I discuss some metaphysical consequences of an unorthodox approach to the problem of the identity and individuality of "indistinguishable" quantum particles. This approach is based on the assumption that the only admissible way of individuating separate components of a given system is with the help of the permutation-invariant qualitative properties of the total system. Such a method of individuation, when applied to fermionic compositions occupying so-called GMW-nonentangled states, yields highly implausible consequences regarding the number of distinct components of a given composite system. I specify the problem (which I call the problem of fermionic inflation) in detail, and I consider several strategies of solving it. The preferred solution of the problem is based on the premise that spatial location should play a privileged role in identifying and making reference to quantum-mechanical systems.

Screening of the two-component-system histidine kinases of Listeria monocytogenes EGD-e. LiaS is needed for growth under heat, acid, alkali, osmotic, ethanol and oxidative stresses.

PubMed

Pöntinen, Anna; Lindström, Miia; Skurnik, Mikael; Korkeala, Hannu

2017-08-01

To study the role of each two-component system (TCS) histidine kinase (HK) in stress tolerance of Listeria monocytogenes EGD-e, we monitored the growth of individual HK deletion mutant strains under heat (42.5 °C), acid (pH 5.6), alkali (pH 9.4), osmotic (6% NaCl), ethanol (3.5 vol%), and oxidative (5 mM H 2 O 2 ) stresses. The growth of ΔliaS (Δlmo1021) strain was impaired under each stress, with the most notable decrease under heat and osmotic stresses. The ΔvirS (Δlmo1741) strain showed nearly completely restricted growth at high temperature and impaired growth in ethanol. The growth of ΔagrC (Δlmo0050) strain was impaired under osmotic stress and slightly under oxidative stress. We successfully complemented the HK mutations using a novel allelic exchange based approach. This approach avoided the copy-number problems associated with in trans complementation from a plasmid. The mutant phenotypes were restored to the wild-type level in the complemented strains. This study reveals novel knowledge on the HKs needed for growth of L. monocytogenes EGD-e under abovementioned stress conditions, with LiaS playing multiple roles in stress tolerance of L. monocytogenes EGD-e. Copyright © 2017 Elsevier Ltd. All rights reserved.

The SaeRS Two-Component System Controls Survival of Staphylococcus aureus in Human Blood through Regulation of Coagulase

PubMed Central

Guo, Haiyong; Hall, Jeffrey W.; Yang, Junshu; Ji, Yinduo

2017-01-01

The SaeRS two-component system plays important roles in regulation of key virulence factors and pathogenicity. In this study, however, we found that the deletion mutation of saeRS enhanced bacterial survival in human blood, whereas complementation of the mutant with SaeRS returned survival to wild-type levels. Moreover, these phenomena were observed in different MRSA genetic background isolates, including HA-MRSA WCUH29, CA-MRSA 923, and MW2. To elucidate which gene(s) regulated by SaeRS contribute to the effect, we conducted a series of complementation studies with selected known SaeRS target genes in trans. We found coagulase complementation abolished the enhanced survival of the SaeRS mutant in human blood. The coa and saeRS deletion mutants exhibited a similar survival phenotype in blood. Intriguingly, heterologous expression of coagulase decreased survival of S. epidermidis in human blood. Further, the addition of recombinant coagulase to blood significantly decreased the survival of S. aureus. Further, analysis revealed staphylococcal resistance to killing by hydrogen peroxide was partially dependent on the presence or absence of coagulase. Furthermore, complementation with coagulase, but not SaeRS, returned saeRS/coa double mutant survival in blood to wild-type levels. These data indicate SaeRS modulates bacterial survival in blood in coagulase-dependent manner. Our results provide new insights into the role of staphylococcal SaeRS and coagulase on bacterial survival in human blood. PMID:28611950

The Race Toward Becoming Operationally Responsive in Space

NASA Astrophysics Data System (ADS)

Nagy, J.; Hernandez, V.; Strunce, R.

The US Air Force Research Laboratory (AFRL) is currently supporting the joint Operationally Responsive Space (ORS) program with two aggressive research space programs. The goal of the ORS program is to improve the responsiveness of space capabilities to meet national security requirements. ORS systems aim to provide operational space capabilities as well as flexibility and responsiveness to the theater that do not exist today. ORS communication, navigation, and Intelligence, Surveillance and Reconnaissance (ISR) satellites are being designed to rapidly meet near term space needs of in-theater tactical forces by supporting contingency operations, such as increased communication bandwidth, and ISR imagery over the theater for a limited period to support air, ground, and naval force missions. This paper will discuss how AFRL/RHA is supporting the ORS effort and describe the hardware and software being developed with a particular focus on the Satellite Design Tool for plug-n-play satellites (SDT). AFRLs Space Vehicles Directorate together with the Scientific Simulation, Inc. was the first to create the Plug-and-play (PnP) satellite design for rapid construction through modular components that encompass the structural panels, as well as the guidance and health/status components. Expansion of the PnP technology is currently being led by AFRL's Human Effectiveness Directorate and Star Technologies Corp. by pushing the boundaries of mobile hardware and software technology through the development of the teams "Training and Tactical ORS Operations (TATOO) Laboratory located in Great Falls, VA. The TATOO Laboratory provides a computer-based simulation environment directed at improving Warfighters space capability responsiveness by delivering the means to create and exercise methods of in-theater tactical satellite tasking for and by the Warfighter. In an effort to further support the evolution of ORS technologies with Warfighters involvement, Star recently started coordinating the integration of the TATOO Laboratory with a satellite robotics test bed. Accessible via the TATOO Lab, the robotics test bed will be used to demonstrate and evaluate leading edge satellite technologies, such as Guidance Navigation and Control, attitude control, formation flying, and plug-and-play electronics. The test bed will consist of a Mission Control Center with wireless control and telemetry, an exceptionally flat and smooth floor area, and two robotic satellite simulators equipped with next generation plug-and-play hardware.

Extracellular proteome analysis of Leptospira interrogans serovar Lai.

PubMed

Zeng, Lingbing; Zhang, Yunyi; Zhu, Yongzhang; Yin, Haidi; Zhuang, Xuran; Zhu, Weinan; Guo, Xiaokui; Qin, Jinhong

2013-10-01

Abstract Leptospirosis is one of the most important zoonoses. Leptospira interrogans serovar Lai is a pathogenic spirochete that is responsible for leptospirosis. Extracellular proteins play an important role in the pathogenicity of this bacterium. In this study, L. interrogans serovar Lai was grown in protein-free medium; the supernatant was collected and subsequently analyzed as the extracellular proteome. A total of 66 proteins with more than two unique peptides were detected by MS/MS, and 33 of these were predicted to be extracellular proteins by a combination of bioinformatics analyses, including Psortb, cello, SoSuiGramN and SignalP. Comparisons of the transcriptional levels of these 33 genes between in vivo and in vitro conditions revealed that 15 genes were upregulated and two genes were downregulated in vivo compared to in vitro. A BLAST search for the components of secretion system at the genomic and proteomic levels revealed the presence of the complete type I secretion system and type II secretion system in this strain. Moreover, this strain also exhibits complete Sec translocase and Tat translocase systems. The extracellular proteome analysis of L. interrogans will supplement the previously generated whole proteome data and provide more information for studying the functions of specific proteins in the infection process and for selecting candidate molecules for vaccines or diagnostic tools for leptospirosis.

Systems and methods for measuring component matching

NASA Technical Reports Server (NTRS)

Courter, Kelly J. (Inventor); Slenk, Joel E. (Inventor)

2006-01-01

Systems and methods for measuring a contour match between adjacent components are disclosed. In one embodiment, at least two pressure sensors are located between adjacent components. Each pressure sensor is adapted to obtain a pressure measurement at a location a predetermined distance away from the other pressure sensors, and to output a pressure measurement for each sensor location. An output device is adapted to receive the pressure measurements from at least two pressure sensors and display the pressure measurements. In one aspect, the pressure sensors include flexible thin film pressure sensors. In accordance with other aspects of the invention, a method is provided for measuring a contour match between two interfacing components including measuring at least one pressure applied to at least one sensor between the interfacing components.

Enhancement of increments in spectral amplitude: further evidence for a mechanism based on central adaptation.

PubMed

Carcagno, Samuele; Semal, Catherine; Demany, Laurent

2013-01-01

The threshold for detecting a tone in a multitone masker is lower when the masker-plus-signal stimulus is preceded by a copy of the masker. One potential explanation of this "enhancement" phenomenon is that the -precursor stimulus acts as a "template" of the subsequent masker, thus helping listeners to segregate the signal from the masker. To assess this idea, we measured enhancement for precursors that were perceptually similar to the masker and for precursors that were made dissimilar to the masker by gating their components asynchronously. We found that the two types of precursor produced similar amounts of enhancement. This was true not only when the precursor and the subsequent test stimulus were presented to the same ear but also when they were presented to opposite ears. In a second experiment, we checked that the precursors with asynchronously gated components were perceptually poor templates of the subsequent maskers. Listeners now had to discriminate between test stimuli -containing the same components as the precursor and test stimuli containing all but one of the precursor components. We found that in this experimental situation, where enhancement could play no role, gating the precursor components asynchronously disrupted performance. Overall, our results are inconsistent with the hypothesis that precursors producing enhancement are beneficial because they are used as perceptual templates of the masker. Our results are instead consistent with an -explanation of enhancement based on selective neural adaptation taking place at a central locus of the auditory system.

Robust high-performance control for robotic manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1989-01-01

Model-based and performance-based control techniques are combined for an electrical robotic control system. Thus, two distinct and separate design philosophies were merged into a single control system having a control law formulation including two distinct and separate components, each of which yields a respective signal componet that is combined into a total command signal for the system. Those two separate system components include a feedforward controller and feedback controller. The feedforward controller is model-based and contains any known part of the manipulator dynamics that can be used for on-line control to produce a nominal feedforward component of the system's control signal. The feedback controller is performance-based and consists of a simple adaptive PID controller which generates an adaptive control signal to complement the nomical feedforward signal.

The development of an autonomous gust insensitive unmanned aerial vehicle

NASA Astrophysics Data System (ADS)

Pisano, William James

The study of a small Unmanned Aerial Vehicle (UAV) that is designed towards eventual operation in harsh storm-like conditions is presented. Investigation of the aircraft equations of motion shows that the selection of certain aerodynamic derivatives has a significant effect on the gust response of a small unmanned aircraft. Analytical comparison of this newly formulated Autonomous Gust Insensitive Aircraft (AGIA) to a conventionally designed aircraft shows a significant reduction in undesirable roll motion caused by gusts. A simulation is presented showing that the AGIA is capable of operating in more extreme environments than a conventional aircraft, and puts less strain on the control system components in both extreme and calm environments. The role that aircraft size plays in gust response is also studied. Pilot instinct dictates that smaller aircraft are more difficult to fly in windy environments than larger ones. This phenomenon is investigated using an analytic approach, providing insight into why smaller aircraft are indeed more difficult to fly in more challenging environments. As an aircraft gets smaller, its natural aerodynamic modes and response get faster. In an ideal system, this does not limit small aircraft to poor performance (in fact it will be shown that idealized small aircraft theoretically perform better than their larger counterparts). A more realistic system is presented that includes not only aerodynamics, but also realistic sensor and actuator dynamics. It is shown that these additional dynamics become a limiting factor in control system performance, and thus limit the closed-loop flight performance of small aircraft in turbulent environments. It is shown that the AGIA design approach plays a more significant role the as an aircraft gets smaller. To provide experimental validation of the gust insensitive theory presented herein, a representative small conventional aircraft was built alongside a similar aircraft that incorporated the AGIA design characteristics. These two aircraft were flown simultaneously and autonomously using the autopilot developed by the Author. Data from this experiment strongly supports the hypothesis that the AGIA is less sensitive to gusts than its conventional counterpart, and that flight of the AGIA puts less strain on the control system components in flight.

Functional Features of TonB Energy Transduction Systems of Acinetobacter baumannii

PubMed Central

Zimbler, Daniel L.; Arivett, Brock A.; Beckett, Amber C.; Menke, Sharon M.

2013-01-01

Acinetobacter baumannii is an opportunistic pathogen that causes severe nosocomial infections. Strain ATCC 19606T utilizes the siderophore acinetobactin to acquire iron under iron-limiting conditions encountered in the host. Accordingly, the genome of this strain has three tonB genes encoding proteins for energy transduction functions needed for the active transport of nutrients, including iron, through the outer membrane. Phylogenetic analysis indicates that these tonB genes, which are present in the genomes of all sequenced A. baumannii strains, were acquired from different sources. Two of these genes occur as components of tonB-exbB-exbD operons and one as a monocistronic copy; all are actively transcribed in ATCC 19606T. The abilities of components of these TonB systems to complement the growth defect of Escherichia coli W3110 mutants KP1344 (tonB) and RA1051 (exbBD) under iron-chelated conditions further support the roles of these TonB systems in iron acquisition. Mutagenesis analysis of ATCC 19606T tonB1 (subscripted numbers represent different copies of genes or proteins) and tonB2 supports this hypothesis: their inactivation results in growth defects in iron-chelated media, without affecting acinetobactin biosynthesis or the production of the acinetobactin outer membrane receptor protein BauA. In vivo assays using Galleria mellonella show that each TonB protein is involved in, but not essential for, bacterial virulence in this infection model. Furthermore, we observed that TonB2 plays a role in the ability of bacteria to bind to fibronectin and to adhere to A549 cells by uncharacterized mechanisms. Taken together, these results indicate that A. baumannii ATCC 19606T produces three independent TonB proteins, which appear to provide the energy-transducing functions needed for iron acquisition and cellular processes that play a role in the virulence of this pathogen. PMID:23817614

Broad-Band Analysis of Polar Motion Excitations

NASA Astrophysics Data System (ADS)

Chen, J.

2016-12-01

Earth rotational changes, i.e. polar motion and length-of-day (LOD), are driven by two types of geophysical excitations: 1) mass redistribution within the Earth system, and 2) angular momentum exchange between the solid Earth (more precisely the crust) and other components of the Earth system. Accurate quantification of Earth rotational excitations has been difficult, due to the lack of global-scale observations of mass redistribution and angular momentum exchange. The over 14-years time-variable gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) have provided a unique means for quantifying Earth rotational excitations from mass redistribution in different components of the climate system. Comparisons between observed Earth rotational changes and geophysical excitations estimated from GRACE, satellite laser ranging (SLR) and climate models show that GRACE-derived excitations agree remarkably well with polar motion observations over a broad-band of frequencies. GRACE estimates also suggest that accelerated polar region ice melting in recent years and corresponding sea level rise have played an important role in driving long-term polar motion as well. With several estimates of polar motion excitations, it is possible to estimate broad-band noise variance and noise power spectra in each, given reasonable assumptions about noise independence. Results based on GRACE CSR RL05 solutions clearly outperform other estimates with the lowest noise levels over a broad band of frequencies.

The Effects of an Abolishing Operation Intervention Component on Play Skills, Challenging Behavior, and Stereotypy

ERIC Educational Resources Information Center

Lang, Russell; O'Reilly, Mark; Sigafoos, Jeff; Machalicek, Wendy; Rispoli, Mandy; Lancioni, Giulio E.; Aguilar, Jeannie; Fragale, Christina

2010-01-01

The purpose of this study was to reduce stereotypy and challenging behavior during play skills instruction by adding an abolishing operation component (AOC) to the intervention strategy. An alternating treatments design compared one condition in which participants were allowed to engage in stereotypy freely before beginning the play skills…

Systems biology of cellular membranes: a convergence with biophysics.

PubMed

Chabanon, Morgan; Stachowiak, Jeanne C; Rangamani, Padmini

2017-09-01

Systems biology and systems medicine have played an important role in the last two decades in shaping our understanding of biological processes. While systems biology is synonymous with network maps and '-omics' approaches, it is not often associated with mechanical processes. Here, we make the case for considering the mechanical and geometrical aspects of biological membranes as a key step in pushing the frontiers of systems biology of cellular membranes forward. We begin by introducing the basic components of cellular membranes, and highlight their dynamical aspects. We then survey the functions of the plasma membrane and the endomembrane system in signaling, and discuss the role and origin of membrane curvature in these diverse cellular processes. We further give an overview of the experimental and modeling approaches to study membrane phenomena. We close with a perspective on the converging futures of systems biology and membrane biophysics, invoking the need to include physical variables such as location and geometry in the study of cellular membranes. WIREs Syst Biol Med 2017, 9:e1386. doi: 10.1002/wsbm.1386 For further resources related to this article, please visit the WIREs website. © 2017 Wiley Periodicals, Inc.

Native structure of a type IV secretion system core complex essential for Legionella pathogenesis.

PubMed

Kubori, Tomoko; Koike, Masafumi; Bui, Xuan Thanh; Higaki, Saori; Aizawa, Shin-Ichi; Nagai, Hiroki

2014-08-12

Bacterial type IV secretion systems are evolutionarily related to conjugation systems and play a pivotal role in infection by delivering numerous virulence factors into host cells. Using transmission electron microscopy, we report the native molecular structure of the core complex of the Dot/Icm type IV secretion system encoded by Legionella pneumophila, an intracellular human pathogen. The biochemically isolated core complex, composed of at least five proteins--DotC, DotD, DotF, DotG, and DotH--has a ring-shaped structure. Intriguingly, morphologically distinct premature complexes are formed in the absence of DotG or DotF. Our data suggest that DotG forms a central channel spanning inner and outer membranes. DotF, a component dispensable for type IV secretion, plays a role in efficient embedment of DotG into the functional core complex. These results highlight a common scheme for the biogenesis of transport machinery.

Remarks on the regularity criteria of three-dimensional magnetohydrodynamics system in terms of two velocity field components

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamazaki, Kazuo

2014-03-15

We study the three-dimensional magnetohydrodynamics system and obtain its regularity criteria in terms of only two velocity vector field components eliminating the condition on the third component completely. The proof consists of a new decomposition of the four nonlinear terms of the system and estimating a component of the magnetic vector field in terms of the same component of the velocity vector field. This result may be seen as a component reduction result of many previous works [C. He and Z. Xin, “On the regularity of weak solutions to the magnetohydrodynamic equations,” J. Differ. Equ. 213(2), 234–254 (2005); Y. Zhou,more » “Remarks on regularities for the 3D MHD equations,” Discrete Contin. Dyn. Syst. 12(5), 881–886 (2005)].« less

MoRFchibi SYSTEM: software tools for the identification of MoRFs in protein sequences.

PubMed

Malhis, Nawar; Jacobson, Matthew; Gsponer, Jörg

2016-07-08

Molecular recognition features, MoRFs, are short segments within longer disordered protein regions that bind to globular protein domains in a process known as disorder-to-order transition. MoRFs have been found to play a significant role in signaling and regulatory processes in cells. High-confidence computational identification of MoRFs remains an important challenge. In this work, we introduce MoRFchibi SYSTEM that contains three MoRF predictors: MoRFCHiBi, a basic predictor best suited as a component in other applications, MoRFCHiBi_ Light, ideal for high-throughput predictions and MoRFCHiBi_ Web, slower than the other two but best for high accuracy predictions. Results show that MoRFchibi SYSTEM provides more than double the precision of other predictors. MoRFchibi SYSTEM is available in three different forms: as HTML web server, RESTful web server and downloadable software at: http://www.chibi.ubc.ca/faculty/joerg-gsponer/gsponer-lab/software/morf_chibi/. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Reinforced dynamics for enhanced sampling in large atomic and molecular systems

NASA Astrophysics Data System (ADS)

Zhang, Linfeng; Wang, Han; E, Weinan

2018-03-01

A new approach for efficiently exploring the configuration space and computing the free energy of large atomic and molecular systems is proposed, motivated by an analogy with reinforcement learning. There are two major components in this new approach. Like metadynamics, it allows for an efficient exploration of the configuration space by adding an adaptively computed biasing potential to the original dynamics. Like deep reinforcement learning, this biasing potential is trained on the fly using deep neural networks, with data collected judiciously from the exploration and an uncertainty indicator from the neural network model playing the role of the reward function. Parameterization using neural networks makes it feasible to handle cases with a large set of collective variables. This has the potential advantage that selecting precisely the right set of collective variables has now become less critical for capturing the structural transformations of the system. The method is illustrated by studying the full-atom explicit solvent models of alanine dipeptide and tripeptide, as well as the system of a polyalanine-10 molecule with 20 collective variables.

Modelling of Biometric Identification System with Given Parameters Using Colored Petri Nets

NASA Astrophysics Data System (ADS)

Petrosyan, G.; Ter-Vardanyan, L.; Gaboutchian, A.

2017-05-01

Biometric identification systems use given parameters and function on the basis of Colored Petri Nets as a modelling language developed for systems in which communication, synchronization and distributed resources play an important role. Colored Petri Nets combine the strengths of Classical Petri Nets with the power of a high-level programming language. Coloured Petri Nets have both, formal intuitive and graphical presentations. Graphical CPN model consists of a set of interacting modules which include a network of places, transitions and arcs. Mathematical representation has a well-defined syntax and semantics, as well as defines system behavioural properties. One of the best known features used in biometric is the human finger print pattern. During the last decade other human features have become of interest, such as iris-based or face recognition. The objective of this paper is to introduce the fundamental concepts of Petri Nets in relation to tooth shape analysis. Biometric identification systems functioning has two phases: data enrollment phase and identification phase. During the data enrollment phase images of teeth are added to database. This record contains enrollment data as a noisy version of the biometrical data corresponding to the individual. During the identification phase an unknown individual is observed again and is compared to the enrollment data in the database and then system estimates the individual. The purpose of modeling biometric identification system by means of Petri Nets is to reveal the following aspects of the functioning model: the efficiency of the model, behavior of the model, mistakes and accidents in the model, feasibility of the model simplification or substitution of its separate components for more effective components without interfering system functioning. The results of biometric identification system modeling and evaluating are presented and discussed.

Business logic for geoprocessing of distributed geodata

NASA Astrophysics Data System (ADS)

Kiehle, Christian

2006-12-01

This paper describes the development of a business-logic component for the geoprocessing of distributed geodata. The business logic acts as a mediator between the data and the user, therefore playing a central role in any spatial information system. The component is used in service-oriented architectures to foster the reuse of existing geodata inventories. Based on a geoscientific case study of groundwater vulnerability assessment and mapping, the demands for such architectures are identified with special regard to software engineering tasks. Methods are derived from the field of applied Geosciences (Hydrogeology), Geoinformatics, and Software Engineering. In addition to the development of a business logic component, a forthcoming Open Geospatial Consortium (OGC) specification is introduced: the OGC Web Processing Service (WPS) specification. A sample application is introduced to demonstrate the potential of WPS for future information systems. The sample application Geoservice Groundwater Vulnerability is described in detail to provide insight into the business logic component, and demonstrate how information can be generated out of distributed geodata. This has the potential to significantly accelerate the assessment and mapping of groundwater vulnerability. The presented concept is easily transferable to other geoscientific use cases dealing with distributed data inventories. Potential application fields include web-based geoinformation systems operating on distributed data (e.g. environmental planning systems, cadastral information systems, and others).

A Proven Ground System Architecture for Promoting Collaboration and Common Solutions at NASA

NASA Technical Reports Server (NTRS)

Smith, Danford

2005-01-01

Requirement: Improve how NASA develops and maintains ground data systems for dozens of missions, with a couple new missions always in the development phase. Decided in 2001 on enhanced message-bus architecture. Users offered choices for major components. They plug and play because key interfaces are all the same. Can support COTS, heritage, and new software. Even the middleware can be switched. Project name: GMSEC. Goddard Mission Services Evolution Center.

Development of the prototype pneumatic transfer system for ITER neutron activation system.

PubMed

Cheon, M S; Seon, C R; Pak, S; Lee, H G; Bertalot, L

2012-10-01

The neutron activation system (NAS) measures neutron fluence at the first wall and the total neutron flux from the ITER plasma, providing evaluation of the fusion power for all operational phases. The pneumatic transfer system (PTS) is one of the key components of the NAS for the proper operation of the system, playing a role of transferring encapsulated samples between the capsule loading machine, irradiation stations, counting stations, and disposal bin. For the validation and the optimization of the design, a prototype of the PTS was developed and capsule transfer tests were performed with the developed system.

Expanding the Reach of Physics-Engaging Students in Interdisciplinary Research Involving complex, real-world situation

NASA Astrophysics Data System (ADS)

Bililign, Solomon

2014-03-01

Physics plays a very important role in most interdisciplinary efforts and can provide a solid foundation for students. Retention of students in STEM areas can be facilitated by enhanced interdisciplinary education and research since students are strongly attracted to research with societal relevance and show increasing enthusiasm about problems that have practical consequences. One such area of research is a collaborative Earth System Science. The Earth System is dynamic and complex. It is comprised of diverse components that interact. By providing students the opportunities to work in interdisciplinary groups on a problem that reflects a complex, real-world situation they can see the linkages between components of the Earth system that encompass climate and all its components (weather precipitation, temperature, etc.) and technology development and deployment of sensors and sensor networks and social impacts. By involving students in the creation of their own personalized professional development plan, students are more focused and engaged and are more likely to remain in the program.

Dynamic energy budget modeling reveals the potential of future growth and calcification for the coccolithophore Emiliania huxleyi in an acidified ocean.

PubMed

Muller, Erik B; Nisbet, Roger M

2014-06-01

Ocean acidification is likely to impact the calcification potential of marine organisms. In part due to the covarying nature of the ocean carbonate system components, including pH and CO2 and CO3(2-) levels, it remains largely unclear how each of these components may affect calcification rates quantitatively. We develop a process-based bioenergetic model that explains how several components of the ocean carbonate system collectively affect growth and calcification rates in Emiliania huxleyi, which plays a major role in marine primary production and biogeochemical carbon cycling. The model predicts that under the IPCC A2 emission scenario, its growth and calcification potential will have decreased by the end of the century, although those reductions are relatively modest. We anticipate that our model will be relevant for many other marine calcifying organisms, and that it can be used to improve our understanding of the impact of climate change on marine systems. © 2014 John Wiley & Sons Ltd.

Growth phase-dependent activation of the DccRS regulon of Campylobacter jejuni

USDA-ARS?s Scientific Manuscript database

Two-component systems are widespread prokaryotic signal transduction devices which allow the regulation of cellular functions in response to changing environmental conditions. The two-component system DccRS (Cj1223-Cj1222) of Campylobacter jejuni is important for the colonization of chickens. Here w...

Localised Nonlinear Waves in the Three-Component Coupled Hirota Equations

NASA Astrophysics Data System (ADS)

Xu, Tao; Chen, Yong

2017-10-01

We construct the Lax pair and Darboux transformation for the three-component coupled Hirota equations including higher-order effects such as third-order dispersion, self-steepening, and stimulated Raman scattering. A special vector solution of the Lax pair with 4×4 matrices for the three-component Hirota system is elaborately generated, based on this vector solution, various types of mixed higher-order localised waves are derived through the generalised Darboux transformation. Instead of considering various arrangements of the three potential functions q1, q2, and q3, here, the same combination is considered as the same type solution. The first- and second-order localised waves are mainly discussed in six mixed types: (1) the hybrid solutions degenerate to the rational ones and three components are all rogue waves; (2) two components are hybrid solutions between rogue wave (RW) and breather (RW+breather), and one component is interactional solution between RW and dark soliton (RW+dark soliton); (3) two components are RW+dark soliton, and one component is RW+bright soliton; (4) two components are RW+breather, and one component is RW+bright soliton; (5) two components are RW+dark soliton, and one component is RW+bright soliton; (6) three components are all RW+breather. Moreover, these nonlinear localised waves merge with each other by increasing the absolute values of two free parameters α, β. These results further uncover some striking dynamic structures in the multicomponent coupled system.

Deepwater seismic acquisition technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caldwell, J.

1996-09-01

Although truly new technology is not required for successful acquisition of seismic data in deep Gulf of Mexico waters, it is helpful to review some basic aspects of these seismic surveys. Additionally, such surveys are likely to see early use of some emerging new technology which can improve data quality. Because such items as depth imaging, borehole seismic, 4-D and marine 3-component recording were mentioned in the May 1996 issue of World Oil, they are not discussed again here. However, these technologies will also play some role in the deepwater seismic activities. What is covered in this paper are somemore » new considerations for: (1) longer data records needed in deeper water, (2) some pros and cons of very long steamer use, and (3) two new commercial systems for quantifying data quality.« less

Yogic exercises and health--a psycho-neuro immunological approach.

PubMed

Kulkarni, D D; Bera, T K

2009-01-01

Relaxation potential of yogic exercises seems to play a vital role in establishing psycho-physical health in reversing the psycho-immunology of emotions under stress based on breath and body awareness. However, mechanism of yogic exercises for restoring health and fitness components operating through psycho-neuro-immunological pathways is unknown. Therefore, a hybrid model of human information processing-psycho-neuroendocrine (HIP-PNE) network has been proposed to reveal the importance of yogic information processing. This study focuses on two major pathways of information processing involving cortical and hypothalamo-pituitary-adrenal axis (HPA) interactions with a deep reach molecular action on cellular, neuro-humoral and immune system in reversing stress mediated diseases. Further, the proposed HIP-PNE model has ample of experimental potential for objective evaluation of yogic view of health and fitness.

The Neuroendocrinology of the Microbiota-Gut-Brain Axis: A Behavioural Perspective.

PubMed

Cussotto, Sofia; Sandhu, Kiran V; Dinan, Timothy G; Cryan, John F

2018-05-10

The human gut harbours trillions of symbiotic bacteria that play a key role in programming different aspects of host physiology in health and disease. These intestinal microbes are also key components of the gut-brain axis, the bidirectional communication pathway between the gut and the central nervous system (CNS). In addition, the CNS is closely interconnected with the endocrine system to regulate many physiological processes. An expanding body of evidence is supporting the notion that gut microbiota modifications and/or manipulations may also play a crucial role in the manifestation of specific behavioural responses regulated by neuroendocrine pathways. In this review, we will focus on how the intestinal microorganisms interact with elements of the host neuroendocrine system to modify behaviours relevant to stress, eating behaviour, sexual behaviour, social behaviour, cognition and addiction. Copyright © 2018. Published by Elsevier Inc.

[Research progress on carbon sink function of agroforestry system under climate change].

PubMed

Xie, Ting-Ting; Su, Pei-Xi; Zhou, Zi-Juan; Shan, Li-Shan

2014-10-01

As a land comprehensive utilization system, agroforestry system can absorb and fix CO2 effectively to increase carbon storage, and also reduces greenhouse effect convincingly while reaching the aim of harvest. The regulatory role in CO2 makes humans realize that agroforestry systems have significant superiority compared with single cropping systems, therefore, understanding the carbon sinks of different components in an agroforestry system and its influencing factors play an important role in studying global carbon cycle and accurate evaluation of carbon budget. This paper reviewed the concept and classification of agroforestry system, and then the carbon sequestration potentials of different components in agroforestry systems and influencing factors. It was concluded that the carbon sequestration rate of plants from different agroforestry systems in different regions are highly variable, ranging from 0.59 to 11.08 t C · hm(-2) · a(-1), and it is mainly influenced by climatic factors and the characteristics of agroforestry systems (species composition, tree density and stand age). The soil C sequestration of any agroforestry system is influenced by the amount and quality of biomass input provided by tree and nontree components of the system and the soil properties such as soil texture and soil structure. Overall the amount of carbon storage in any agroforestry system depends on the structure and function of its each component. The future studies should focus on the carbon sink functions of structurally optimized agroforestry systems, the temporal variation and spatial distribution pattern of carbon storage in agroforestry system and its carbon sequestration mechanism in a long time.

Toward a social-ecological theory of forest macrosystems for improved ecosystem management

USGS Publications Warehouse

Kleindl, William J.; Stoy, Paul C.; Binford, Michael W.; Desai, Ankur R.; Dietze, Michael C.; Schultz, Courtney A.; Starr, Gregory; Staudhammer, Christina; Wood, David J. A.

2018-01-01

The implications of cumulative land-use decisions and shifting climate on forests, require us to integrate our understanding of ecosystems, markets, policy, and resource management into a social-ecological system. Humans play a central role in macrosystem dynamics, which complicates ecological theories that do not explicitly include human interactions. These dynamics also impact ecological services and related markets, which challenges economic theory. Here, we use two forest macroscale management initiatives to develop a theoretical understanding of how management interacts with ecological functions and services at these scales and how the multiple large-scale management goals work either in consort or conflict with other forest functions and services. We suggest that calling upon theories developed for organismal ecology, ecosystem ecology, and ecological economics adds to our understanding of social-ecological macrosystems. To initiate progress, we propose future research questions to add rigor to macrosystem-scale studies: (1) What are the ecosystem functions that operate at macroscales, their necessary structural components, and how do we observe them? (2) How do systems at one scale respond if altered at another scale? (3) How do we both effectively measure these components and interactions, and communicate that information in a meaningful manner for policy and management across different scales?

Enhanced Color Mercury Map

NASA Image and Video Library

2017-12-08

This colorful view of Mercury was produced by using images from the color base map imaging campaign during MESSENGER's primary mission. These colors are not what Mercury would look like to the human eye, but rather the colors enhance the chemical, mineralogical, and physical differences between the rocks that make up Mercury's surface. This specific color combination places the second principle component in the red channel, the first principle component in the green channel, and the ratio of the 430 nm/1000 nm filters in the blue channel. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Capillary thermoconcentration instability and processes of heat and mass transfer in laser technology

NASA Astrophysics Data System (ADS)

Maiorov, Vladimir S.

2002-04-01

The paper gives a description of the phenomenon that has a considerable, and often a decisive, influence on the course of physical processes under laser radiation interaction with a substance having at least one liquid phase. The explanation of the essence of this phenomenon lies at the intersection of two branches of science: mechanics of liquids and gases, and physical chemistry (thermodynamics of heterogeneous systems). Capillary thermo-concentration instability (CTCI) is present at any non-isotropic input of energy to a heterogeneous thermodynamical system having several phases. This instability manifests itself at the phase boundary and causes processes of mass transfer, redistribution of components, emergence of new phases, relaxation vibrations. This phenomenon is most pronounced in local processes at interaction of laser radiation with matter. The theory and practice of this phenomenon unite and describe a new class of effects widely spread in nature, which play a decisive role in many physical and chemical processes and find even more various spheres of practical application. A number of examples of capillary thermo- concentration instability application are given: separation of liquid mixtures to components under thermal action of laser beam; a new method of thermal silver-free photography; control of liquid metal convection in laser alloying.

Recent Advances in Macrocyclic Fluorescent Probes for Ion Sensing.

PubMed

Wong, Joseph K-H; Todd, Matthew H; Rutledge, Peter J

2017-01-25

Small-molecule fluorescent probes play a myriad of important roles in chemical sensing. Many such systems incorporating a receptor component designed to recognise and bind a specific analyte, and a reporter or transducer component which signals the binding event with a change in fluorescence output have been developed. Fluorescent probes use a variety of mechanisms to transmit the binding event to the reporter unit, including photoinduced electron transfer (PET), charge transfer (CT), Förster resonance energy transfer (FRET), excimer formation, and aggregation induced emission (AIE) or aggregation caused quenching (ACQ). These systems respond to a wide array of potential analytes including protons, metal cations, anions, carbohydrates, and other biomolecules. This review surveys important new fluorescence-based probes for these and other analytes that have been reported over the past five years, focusing on the most widely exploited macrocyclic recognition components, those based on cyclam, calixarenes, cyclodextrins and crown ethers; other macrocyclic and non-macrocyclic receptors are also discussed.

GeoNetwork powered GI-cat: a geoportal hybrid solution

NASA Astrophysics Data System (ADS)

Baldini, Alessio; Boldrini, Enrico; Santoro, Mattia; Mazzetti, Paolo

2010-05-01

To the aim of setting up a Spatial Data Infrastructures (SDI) the creation of a system for the metadata management and discovery plays a fundamental role. An effective solution is the use of a geoportal (e.g. FAO/ESA geoportal), that has the important benefit of being accessible from a web browser. With this work we present a solution based integrating two of the available frameworks: GeoNetwork and GI-cat. GeoNetwork is an opensource software designed to improve accessibility of a wide variety of data together with the associated ancillary information (metadata), at different scale and from multidisciplinary sources; data are organized and documented in a standard and consistent way. GeoNetwork implements both the Portal and Catalog components of a Spatial Data Infrastructure (SDI) defined in the OGC Reference Architecture. It provides tools for managing and publishing metadata on spatial data and related services. GeoNetwork allows harvesting of various types of web data sources e.g. OGC Web Services (e.g. CSW, WCS, WMS). GI-cat is a distributed catalog based on a service-oriented framework of modular components and can be customized and tailored to support different deployment scenarios. It can federate a multiplicity of catalogs services, as well as inventory and access services in order to discover and access heterogeneous ESS resources. The federated resources are exposed by GI-cat through several standard catalog interfaces (e.g. OGC CSW AP ISO, OpenSearch, etc.) and by the GI-cat extended interface. Specific components implement mediation services for interfacing heterogeneous service providers, each of which exposes a specific standard specification; such components are called Accessors. These mediating components solve providers data modelmultiplicity by mapping them onto the GI-cat internal data model which implements the ISO 19115 Core profile. Accessors also implement the query protocol mapping; first they translate the query requests expressed according to the interface protocols exposed by GI-cat into the multiple query dialects spoken by the resource service providers. Currently, a number of well-accepted catalog and inventory services are supported, including several OGC Web Services, THREDDS Data Server, SeaDataNet Common Data Index, GBIF and OpenSearch engines. A GeoNetwork powered GI-cat has been developed in order to exploit the best of the two frameworks. The new system uses a modified version of GeoNetwork web interface in order to add the capability of querying also the specified GI-cat catalog and not only the GeoNetwork internal database. The resulting system consists in a geoportal in which GI-cat plays the role of the search engine. This new system allows to distribute the query on the different types of data sources linked to a GI-cat. The metadata results of the query are then visualized by the Geonetwork web interface. This configuration was experimented in the framework of GIIDA, a project of the Italian National Research Council (CNR) focused on data accessibility and interoperability. A second advantage of this solution is achieved setting up a GeoNetwork catalog amongst the accessors of the GI-cat instance. Such a configuration will allow in turn GI-cat to run the query against the internal GeoNetwork database. This allows to have both the harvesting and the metadata editor functionalities provided by GeoNetwork and the distributed search functionality of GI-cat available in a consistent way through the same web interface.

Optimal read/write memory system components

NASA Technical Reports Server (NTRS)

Kozma, A.; Vander Lugt, A.; Klinger, D.

1972-01-01

Two holographic data storage and display systems, voltage gradient ionization system, and linear strain manipulation system are discussed in terms of creating fast, high bit density, storage device. Components described include: novel mounting fixture for photoplastic arrays; corona discharge device; and block data composer.

Programming of respiratory health in childhood: influence of outdoor air pollution.

PubMed

Wright, Rosalind J; Brunst, Kelly J

2013-04-01

This overview highlights recent experimental and epidemiological evidence for the programming effects of outdoor air pollution exposures during early development on lung function and chronic respiratory disorders, such as asthma and related allergic disorders. Air pollutants may impact anatomy and/or physiological functioning of the lung and interrelated systems. Programming effects may result from pollutant-induced shifts in a number of molecular, cellular, and physiological states and their interacting systems. Specific key regulatory systems susceptible to programming may influence lung development and vulnerability to respiratory diseases, including both central and peripheral components of neuroendocrine pathways and autonomic nervous system (ANS) functioning which, in turn, influence the immune system. Starting in utero, environmental factors, including air pollutants, may permanently organize these systems toward trajectories of enhanced pediatric (e.g., asthma, allergy) as well as adult disease risk (e.g., chronic obstructive pulmonary disease). Evidence supports a central role of oxidative stress in the toxic effects of air pollution. Additional research suggests xenobiotic metabolism and subcellular components, such as mitochondria are targets of ambient air pollution and play a role in asthma and allergy programming. Mechanisms operating at the level of the placenta are being elucidated. Epigenetic mechanisms may be at the roots of adaptive developmental programming. Optimal coordinated functioning of many complex processes and their networks of interaction are necessary for normal lung development and the maintenance of respiratory health. Outdoor air pollution may play an important role in early programming of respiratory health and is potentially amenable to intervention.

Characterization of mediators of microbial virulence and innate immunity using the Caenorhabditis elegans host-pathogen model.

PubMed

Alegado, Rosanna A; Campbell, Marianne C; Chen, Will C; Slutz, Sandra S; Tan, Man-Wah

2003-07-01

The soil-borne nematode, Caenorhabditis elegans, is emerging as a versatile model in which to study host-pathogen interactions. The worm model has shown to be particularly effective in elucidating both microbial and animal genes involved in toxin-mediated killing. In addition, recent work on worm infection by a variety of bacterial pathogens has shown that a number of virulence regulatory genes mediate worm susceptibility. Many of these regulatory genes, including the PhoP/Q two-component regulators in Salmonella and LasR in Pseudomonas aeruginosa, have also been implicated in mammalian models suggesting that findings in the worm model will be relevant to other systems. In keeping with this concept, experiments aimed at identifying host innate immunity genes have also implicated pathways that have been suggested to play a role in plants and animals, such as the p38 MAP kinase pathway. Despite rapid forward progress using this model, much work remains to be done including the design of more sensitive methods to find effector molecules and further characterization of the exact interaction between invading pathogens and C. elegans' cellular components.

The Ser/Thr Protein Kinase Protein-Protein Interaction Map of M. tuberculosis.

PubMed

Wu, Fan-Lin; Liu, Yin; Jiang, He-Wei; Luan, Yi-Zhao; Zhang, Hai-Nan; He, Xiang; Xu, Zhao-Wei; Hou, Jing-Li; Ji, Li-Yun; Xie, Zhi; Czajkowsky, Daniel M; Yan, Wei; Deng, Jiao-Yu; Bi, Li-Jun; Zhang, Xian-En; Tao, Sheng-Ce

2017-08-01

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis, the leading cause of death among all infectious diseases. There are 11 eukaryotic-like serine/threonine protein kinases (STPKs) in Mtb, which are thought to play pivotal roles in cell growth, signal transduction and pathogenesis. However, their underlying mechanisms of action remain largely uncharacterized. In this study, using a Mtb proteome microarray, we have globally identified the binding proteins in Mtb for all of the STPKs, and constructed the first STPK protein interaction (KPI) map that includes 492 binding proteins and 1,027 interactions. Bioinformatics analysis showed that the interacting proteins reflect diverse functions, including roles in two-component system, transcription, protein degradation, and cell wall integrity. Functional investigations confirmed that PknG regulates cell wall integrity through key components of peptidoglycan (PG) biosynthesis, e.g. MurC. The global STPK-KPIs network constructed here is expected to serve as a rich resource for understanding the key signaling pathways in Mtb, thus facilitating drug development and effective control of Mtb. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

A weighted information criterion for multiple minor components and its adaptive extraction algorithms.

PubMed

Gao, Yingbin; Kong, Xiangyu; Zhang, Huihui; Hou, Li'an

2017-05-01

Minor component (MC) plays an important role in signal processing and data analysis, so it is a valuable work to develop MC extraction algorithms. Based on the concepts of weighted subspace and optimum theory, a weighted information criterion is proposed for searching the optimum solution of a linear neural network. This information criterion exhibits a unique global minimum attained if and only if the state matrix is composed of the desired MCs of an autocorrelation matrix of an input signal. By using gradient ascent method and recursive least square (RLS) method, two algorithms are developed for multiple MCs extraction. The global convergences of the proposed algorithms are also analyzed by the Lyapunov method. The proposed algorithms can extract the multiple MCs in parallel and has advantage in dealing with high dimension matrices. Since the weighted matrix does not require an accurate value, it facilitates the system design of the proposed algorithms for practical applications. The speed and computation advantages of the proposed algorithms are verified through simulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

A shared resource between declarative memory and motor memory.

PubMed

Keisler, Aysha; Shadmehr, Reza

2010-11-03

The neural systems that support motor adaptation in humans are thought to be distinct from those that support the declarative system. Yet, during motor adaptation changes in motor commands are supported by a fast adaptive process that has important properties (rapid learning, fast decay) that are usually associated with the declarative system. The fast process can be contrasted to a slow adaptive process that also supports motor memory, but learns gradually and shows resistance to forgetting. Here we show that after people stop performing a motor task, the fast motor memory can be disrupted by a task that engages declarative memory, but the slow motor memory is immune from this interference. Furthermore, we find that the fast/declarative component plays a major role in the consolidation of the slow motor memory. Because of the competitive nature of declarative and nondeclarative memory during consolidation, impairment of the fast/declarative component leads to improvements in the slow/nondeclarative component. Therefore, the fast process that supports formation of motor memory is not only neurally distinct from the slow process, but it shares critical resources with the declarative memory system.

A shared resource between declarative memory and motor memory

PubMed Central

Keisler, Aysha; Shadmehr, Reza

2010-01-01

The neural systems that support motor adaptation in humans are thought to be distinct from those that support the declarative system. Yet, during motor adaptation changes in motor commands are supported by a fast adaptive process that has important properties (rapid learning, fast decay) that are usually associated with the declarative system. The fast process can be contrasted to a slow adaptive process that also supports motor memory, but learns gradually and shows resistance to forgetting. Here we show that after people stop performing a motor task, the fast motor memory can be disrupted by a task that engages declarative memory, but the slow motor memory is immune from this interference. Furthermore, we find that the fast/declarative component plays a major role in the consolidation of the slow motor memory. Because of the competitive nature of declarative and non-declarative memory during consolidation, impairment of the fast/declarative component leads to improvements in the slow/non-declarative component. Therefore, the fast process that supports formation of motor memory is not only neurally distinct from the slow process, but it shares critical resources with the declarative memory system. PMID:21048140

Independent active and thermodynamic processes govern the nucleolus assembly in vivo

PubMed Central

Falahati, Hanieh; Wieschaus, Eric

2017-01-01

Membraneless organelles play a central role in the organization of protoplasm by concentrating macromolecules, which allows efficient cellular processes. Recent studies have shown that, in vitro, certain components in such organelles can assemble through phase separation. Inside the cell, however, such organelles are multicomponent, with numerous intermolecular interactions that can potentially affect the demixing properties of individual components. In addition, the organelles themselves are inherently active, and it is not clear how the active, energy-consuming processes that occur constantly within such organelles affect the phase separation behavior of the constituent macromolecules. Here, we examine the phase separation model for the formation of membraneless organelles in vivo by assessing the two features that collectively distinguish it from active assembly, namely temperature dependence and reversibility. We use a microfluidic device that allows accurate and rapid manipulation of temperature and examine the quantitative dynamics by which six different nucleolar proteins assemble into the nucleoli of Drosophila melanogaster embryos. Our results indicate that, although phase separation is the main mode of recruitment for four of the studied proteins, the assembly of the other two is irreversible and enhanced at higher temperatures, behaviors indicative of active recruitment to the nucleolus. These two subsets of components differ in their requirements for ribosomal DNA; the two actively assembling components fail to assemble in the absence of ribosomal DNA, whereas the thermodynamically driven components assemble but lose temporal and spatial precision. PMID:28115706

Analytical energy gradient for the two-component normalized elimination of the small component method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zou, Wenli; Filatov, Michael; Cremer, Dieter, E-mail: dcremer@smu.edu

2015-06-07

The analytical gradient for the two-component Normalized Elimination of the Small Component (2c-NESC) method is presented. The 2c-NESC is a Dirac-exact method that employs the exact two-component one-electron Hamiltonian and thus leads to exact Dirac spin-orbit (SO) splittings for one-electron atoms. For many-electron atoms and molecules, the effect of the two-electron SO interaction is modeled by a screened nucleus potential using effective nuclear charges as proposed by Boettger [Phys. Rev. B 62, 7809 (2000)]. The effect of spin-orbit coupling (SOC) on molecular geometries is analyzed utilizing the properties of the frontier orbitals and calculated SO couplings. It is shown thatmore » bond lengths can either be lengthened or shortened under the impact of SOC where in the first case the influence of low lying excited states with occupied antibonding orbitals plays a role and in the second case the jj-coupling between occupied antibonding and unoccupied bonding orbitals dominates. In general, the effect of SOC on bond lengths is relatively small (≤5% of the scalar relativistic changes in the bond length). However, large effects are found for van der Waals complexes Hg{sub 2} and Cn{sub 2}, which are due to the admixture of more bonding character to the highest occupied spinors.« less

Fabrication of micromechanical and microoptical systems by two-photon polymerization

NASA Astrophysics Data System (ADS)

Reinhardt, Carsten; Ovsianikov, A.; Passinger, Sven; Chichkov, Boris N.

2007-01-01

The recently developed two-photon polymerisation technique is used for the fabrication of two- and three-dimensional structures in photosensitive inorganic-organic hybrid material (ORMOCER), in SU8 , and in positive tone resist with resolutions down to 100nm. In this contribution we present applications of this powerful technology for the realization of micromechanical systems and microoptical components. We will demonstrate results on the fabrication of complex movable three-dimensional micromechanical systems and microfluidic components which cannot be realized by other technologies. This approach of structuring photosensitive materials also provides unique possibilities for the fabrication of different microoptical components such as arbitrary shaped microlenses, microprisms, and 3D-photonic crystals with high optical quality.

Structural analysis of health-relevant policy-making information exchange networks in Canada.

PubMed

Contandriopoulos, Damien; Benoît, François; Bryant-Lukosius, Denise; Carrier, Annie; Carter, Nancy; Deber, Raisa; Duhoux, Arnaud; Greenhalgh, Trisha; Larouche, Catherine; Leclerc, Bernard-Simon; Levy, Adrian; Martin-Misener, Ruth; Maximova, Katerina; McGrail, Kimberlyn; Nykiforuk, Candace; Roos, Noralou; Schwartz, Robert; Valente, Thomas W; Wong, Sabrina; Lindquist, Evert; Pullen, Carolyn; Lardeux, Anne; Perroux, Melanie

2017-09-20

Health systems worldwide struggle to identify, adopt, and implement in a timely and system-wide manner the best-evidence-informed-policy-level practices. Yet, there is still only limited evidence about individual and institutional best practices for fostering the use of scientific evidence in policy-making processes The present project is the first national-level attempt to (1) map and structurally analyze-quantitatively-health-relevant policy-making networks that connect evidence production, synthesis, interpretation, and use; (2) qualitatively investigate the interaction patterns of a subsample of actors with high centrality metrics within these networks to develop an in-depth understanding of evidence circulation processes; and (3) combine these findings in order to assess a policy network's "absorptive capacity" regarding scientific evidence and integrate them into a conceptually sound and empirically grounded framework. The project is divided into two research components. The first component is based on quantitative analysis of ties (relationships) that link nodes (participants) in a network. Network data will be collected through a multi-step snowball sampling strategy. Data will be analyzed structurally using social network mapping and analysis methods. The second component is based on qualitative interviews with a subsample of the Web survey participants having central, bridging, or atypical positions in the network. Interviews will focus on the process through which evidence circulates and enters practice. Results from both components will then be integrated through an assessment of the network's and subnetwork's effectiveness in identifying, capturing, interpreting, sharing, reframing, and recodifying scientific evidence in policy-making processes. Knowledge developed from this project has the potential both to strengthen the scientific understanding of how policy-level knowledge transfer and exchange functions and to provide significantly improved advice on how to ensure evidence plays a more prominent role in public policies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hagen, Lea M. Z.; Hagen, Alex; Seibert, Mark

We provide evidence that UGC 1382, long believed to be a passive elliptical galaxy, is actually a giant low surface brightness (GLSB) galaxy that rivals the archetypical GLSB Malin 1 in size. Like other GLSB galaxies, it has two components: a high surface brightness disk galaxy surrounded by an extended low surface brightness (LSB) disk. For UGC 1382, the central component is a lenticular system with an effective radius of 6 kpc. Beyond this, the LSB disk has an effective radius of ∼38 kpc and an extrapolated central surface brightness of ∼26 mag arcsec{sup 2}. Both components have a combinedmore » stellar mass of ∼8 × 10{sup 10} M {sub ⊙}, and are embedded in a massive (10{sup 10} M {sub ⊙}) low-density (<3 M {sub ⊙} pc{sup 2}) HI disk with a radius of 110 kpc, making this one of the largest isolated disk galaxies known. The system resides in a massive dark matter halo of at least 2 × 10{sup 12} M {sub ⊙}. Although possibly part of a small group, its low-density environment likely plays a role in the formation and retention of the giant LSB and HI disks. We model the spectral energy distributions and find that the LSB disk is likely older than the lenticular component. UGC 1382 has UV–optical colors typical of galaxies transitioning through the green valley. Within the LSB disk are spiral arms forming stars at extremely low efficiencies. The gas depletion timescale of ∼10{sup 11} years suggests that UGC 1382 may be a very-long-term resident of the green valley. We find that the formation and evolution of the LSB disk in UGC 1382 is best explained by the accretion of gas-rich LSB dwarf galaxies.« less

Computer-supported games and role plays in teaching water management

NASA Astrophysics Data System (ADS)

Hoekstra, A. Y.

2012-08-01

There is an increasing demand for an interdisciplinary approach in teaching water management. Computer-supported games and role plays offer the potential of creating an environment in which different disciplines come together and in which students are challenged to develop integrated understanding. Two examples are discussed. The River Basin Game is a common-pool resource game in which participants experience the risk of over-abstractions of water in a river basin and learn how this risk relates to the complexity of the system, the conflict between individual and group optimums and the difficulty in achieving good cooperation. The Globalization of Water Role Play makes participants familiar with the global dimension of water management by letting them experience how national governments can integrate considerations of water scarcity and domestic water productivities into decisions on international trade in commodities like food, cotton and bio-energy. The two examples illustrate that play sessions inspire participants to think about the functioning of systems as a whole and to develop good cooperative courses of action, whereby both uncertainties about the system and the presence of different values and perspectives among participants play a role.

Three-Dimensional Visualization of Interfacial Phenomena Using Confocal Microscopy

NASA Astrophysics Data System (ADS)

Shieh, Ian C.

Surfactants play an integral role in numerous functions ranging from stabilizing the emulsion in a favorite salad dressing to organizing the cellular components that make life possible. We are interested in lung surfactant, which is a mixture of lipids and proteins essential for normal respiration because it modulates the surface tension of the air-liquid interface of the thin fluid lining in the lungs. Through this surface tension modulation, lung surfactant ensures effortless lung expansion and prevents lung collapse during exhalation, thereby effecting proper oxygenation of the bloodstream. The function of lung surfactant, as well as numerous interfacial lipid systems, is not solely dictated by the behavior of materials confined to the two-dimensional interface. Rather, the distributions of materials in the liquid subphase also greatly influence the performance of interfacial films of lung surfactant. Therefore, to better understand the behavior of lung surfactant and other interfacial lipid systems, we require a three-dimensional characterization technique. In this dissertation, we have developed a novel confocal microscopy methodology for investigating the interfacial phenomena of surfactants at the air-liquid interface of a Langmuir trough. Confocal microscopy provides the excellent combination of in situ, fast, three-dimensional visualization of multiple components of the lung surfactant system that other characterization techniques lack. We detail the solutions to the numerous challenges encountered when imaging a dynamic air-liquid interface with a high-resolution technique like confocal microscopy. We then use confocal microscopy to elucidate the distinct mechanisms by which a polyelectrolyte (chitosan) and nonadsorbing polymer (polyethylene glycol) restore the function of lung surfactant under inhibitory conditions mimicking the effects of lung trauma. Beyond this physiological model, we also investigate several one- and two-component interfacial films of the various lipid constituents of lung surfactant. Confocal microscopy allows us to use a water-soluble, cationic fluorophore that partitions into the disordered phases of lipid monolayers. By exploiting the properties of this water-soluble fluorophore, we investigate both the phase behavior and electrostatics of the interfacial lipid systems. Overall, we believe the work presented in this dissertation provides the building blocks for establishing confocal microscopy as a ubiquitous characterization technique in the interfacial and surface sciences.

The Ca2+ induced two-component system, CvsSR regulates the Type III secretion system and the extracytoplasmic function sigma-factor AlgU in Pseudomonas syringae pv. tomato DC3000

USDA-ARS?s Scientific Manuscript database

Two-component systems (TCSs) of bacteria regulate many different aspects of the bacterial life cycle including pathogenesis. Most TCSs remain uncharacterized with no information about the signal(s) or regulatory targets and/or role in bacterial pathogenesis. Here, we characterize a TCS in the plant-...

A modeling framework for exposing risks in complex systems.

PubMed

Sharit, J

2000-08-01

This article introduces and develops a modeling framework for exposing risks in the form of human errors and adverse consequences in high-risk systems. The modeling framework is based on two components: a two-dimensional theory of accidents in systems developed by Perrow in 1984, and the concept of multiple system perspectives. The theory of accidents differentiates systems on the basis of two sets of attributes. One set characterizes the degree to which systems are interactively complex; the other emphasizes the extent to which systems are tightly coupled. The concept of multiple perspectives provides alternative descriptions of the entire system that serve to enhance insight into system processes. The usefulness of these two model components derives from a modeling framework that cross-links them, enabling a variety of work contexts to be exposed and understood that would otherwise be very difficult or impossible to identify. The model components and the modeling framework are illustrated in the case of a large and comprehensive trauma care system. In addition to its general utility in the area of risk analysis, this methodology may be valuable in applications of current methods of human and system reliability analysis in complex and continually evolving high-risk systems.

Pathogenesis of Systemic Sclerosis

PubMed Central

Pattanaik, Debendra; Brown, Monica; Postlethwaite, Bradley C.; Postlethwaite, Arnold E.

2015-01-01

Systemic scleroderma (SSc) is one of the most complex systemic autoimmune diseases. It targets the vasculature, connective tissue-producing cells (namely fibroblasts/myofibroblasts), and components of the innate and adaptive immune systems. Clinical and pathologic manifestations of SSc are the result of: (1) innate/adaptive immune system abnormalities leading to production of autoantibodies and cell-mediated autoimmunity, (2) microvascular endothelial cell/small vessel fibroproliferative vasculopathy, and (3) fibroblast dysfunction generating excessive accumulation of collagen and other matrix components in skin and internal organs. All three of these processes interact and affect each other. The disease is heterogeneous in its clinical presentation that likely reflects different genetic or triggering factor (i.e., infection or environmental toxin) influences on the immune system, vasculature, and connective tissue cells. The roles played by other ubiquitous molecular entities (such as lysophospholipids, endocannabinoids, and their diverse receptors and vitamin D) in influencing the immune system, vasculature, and connective tissue cells are just beginning to be realized and studied and may provide insights into new therapeutic approaches to treat SSc. PMID:26106387

A numerical study of blood flow using mixture theory

PubMed Central

Wu, Wei-Tao; Aubry, Nadine; Massoudi, Mehrdad; Kim, Jeongho; Antaki, James F.

2014-01-01

In this paper, we consider the two dimensional flow of blood in a rectangular microfluidic channel. We use Mixture Theory to treat this problem as a two-component system: One component is the red blood cells (RBCs) modeled as a generalized Reiner–Rivlin type fluid, which considers the effects of volume fraction (hematocrit) and influence of shear rate upon viscosity. The other component, plasma, is assumed to behave as a linear viscous fluid. A CFD solver based on OpenFOAM® was developed and employed to simulate a specific problem, namely blood flow in a two dimensional micro-channel, is studied. Finally to better understand this two-component flow system and the effects of the different parameters, the equations are made dimensionless and a parametric study is performed. PMID:24791016

A numerical study of blood flow using mixture theory.

PubMed

Wu, Wei-Tao; Aubry, Nadine; Massoudi, Mehrdad; Kim, Jeongho; Antaki, James F

2014-03-01

In this paper, we consider the two dimensional flow of blood in a rectangular microfluidic channel. We use Mixture Theory to treat this problem as a two-component system: One component is the red blood cells (RBCs) modeled as a generalized Reiner-Rivlin type fluid, which considers the effects of volume fraction (hematocrit) and influence of shear rate upon viscosity. The other component, plasma, is assumed to behave as a linear viscous fluid. A CFD solver based on OpenFOAM ® was developed and employed to simulate a specific problem, namely blood flow in a two dimensional micro-channel, is studied. Finally to better understand this two-component flow system and the effects of the different parameters, the equations are made dimensionless and a parametric study is performed.

Summer Camp: Language Learning beyond the Walls--A Grassroots Model for Summer Immersion Camp

ERIC Educational Resources Information Center

Seewald, Amanda

2012-01-01

In efforts to improve, expand and inspire language learning to become a basic and essential component of the landscape of the educational system, one must reach out beyond the walls of the classroom to engage learners early. Real-world learning and energized, playful, interactive language experiences that inspire can drastically change the…

A National Assessment of the Urban Forest: An Overview

Treesearch

John F. Dwyer; David J. Nowak

2000-01-01

Urban forest management promises to play a critical role in the management of .... our nation's forest resources in the 21st century. Urban forests are significant and diverse ecosystems with intricate connections among their physical, biological, and social components; as well as with other elements of urban and natural resource systems. Urban forests are also...

A Role-Playing Game for a Software Engineering Lab: Developing a Product Line

ERIC Educational Resources Information Center

Zuppiroli, Sara; Ciancarini, Paolo; Gabbrielli, Maurizio

2012-01-01

Software product line development refers to software engineering practices and techniques for creating families of similar software systems from a basic set of reusable components, called shared assets. Teaching how to deal with software product lines in a university lab course is a challenging task, because there are several practical issues that…

Role-Playing and Problem-Based Learning: The Use of Cross-Functional Student Teams in Business Application Development

ERIC Educational Resources Information Center

Pike, Jacqueline C.; Spangler, William; Williams, Valerie; Kollar, Robert

2017-01-01

To create a learning experience which replicates the process by which consultants, systems developers and business end users collaborate to design and implement a business application, a cross-functional student team project was developed and is described. The overall learning experience was distinguished by specific components and characteristics…

Are Amygdalar Volume Alterations in Children with Tourette Syndrome Due to ADHD Comorbidity?

ERIC Educational Resources Information Center

Ludolph, Andrea G.; Pinkhardt, Elmar H.; van Elst, Ludger Tebartz; Libal, Gerhard; Ludolph, Albert C.; Fegert, Jorg M.; Kassubek, Jan

2008-01-01

Recent studies have shown that changes in the basal ganglia circuitry and limbic loops may play an important role both in Tourette syndrome (TS) and attention-deficit-hyperactivity disorder (ADHD). This study aimed to investigate in vivo possible morphological alterations of the amygdala as a key component of the limbic system. Amygdalar and total…

Plastic Transcriptomes Stabilize Immunity to Pathogen Diversity: The Jasmonic Acid and Salicylic Acid Networks within the Arabidopsis/Botrytis Pathosystem[OPEN

PubMed Central

Eshbaugh, Robert; Chen, Fang; Atwell, Susana

2017-01-01

To respond to pathogen attack, selection and associated evolution has led to the creation of plant immune system that are a highly effective and inducible defense system. Central to this system are the plant defense hormones jasmonic acid (JA) and salicylic acid (SA) and crosstalk between the two, which may play an important role in defense responses to specific pathogens or even genotypes. Here, we used the Arabidopsis thaliana-Botrytis cinerea pathosystem to test how the host’s defense system functions against genetic variation in a pathogen. We measured defense-related phenotypes and transcriptomic responses in Arabidopsis wild-type Col-0 and JA- and SA-signaling mutants, coi1-1 and npr1-1, individually challenged with 96 diverse B. cinerea isolates. Those data showed genetic variation in the pathogen influences on all components within the plant defense system at the transcriptional level. We identified four gene coexpression networks and two vectors of defense variation triggered by genetic variation in B. cinerea. This showed that the JA and SA signaling pathways functioned to constrain/canalize the range of virulence in the pathogen population, but the underlying transcriptomic response was highly plastic. These data showed that plants utilize major defense hormone pathways to buffer disease resistance, but not the metabolic or transcriptional responses to genetic variation within a pathogen. PMID:29042403

Plastic Transcriptomes Stabilize Immunity to Pathogen Diversity: The Jasmonic Acid and Salicylic Acid Networks within the Arabidopsis/Botrytis Pathosystem.

PubMed

Zhang, Wei; Corwin, Jason A; Copeland, Daniel; Feusier, Julie; Eshbaugh, Robert; Chen, Fang; Atwell, Susana; Kliebenstein, Daniel J

2017-11-01

To respond to pathogen attack, selection and associated evolution has led to the creation of plant immune system that are a highly effective and inducible defense system. Central to this system are the plant defense hormones jasmonic acid (JA) and salicylic acid (SA) and crosstalk between the two, which may play an important role in defense responses to specific pathogens or even genotypes. Here, we used the Arabidopsis thaliana - Botrytis cinerea pathosystem to test how the host's defense system functions against genetic variation in a pathogen. We measured defense-related phenotypes and transcriptomic responses in Arabidopsis wild-type Col-0 and JA- and SA-signaling mutants, coi1-1 and npr1-1 , individually challenged with 96 diverse B. cinerea isolates. Those data showed genetic variation in the pathogen influences on all components within the plant defense system at the transcriptional level. We identified four gene coexpression networks and two vectors of defense variation triggered by genetic variation in B. cinerea This showed that the JA and SA signaling pathways functioned to constrain/canalize the range of virulence in the pathogen population, but the underlying transcriptomic response was highly plastic. These data showed that plants utilize major defense hormone pathways to buffer disease resistance, but not the metabolic or transcriptional responses to genetic variation within a pathogen. © 2017 American Society of Plant Biologists. All rights reserved.

Nonlinear processing of a multicomponent communication signal by combination-sensitive neurons in the anuran inferior colliculus.

PubMed

Lee, Norman; Schrode, Katrina M; Bee, Mark A

2017-09-01

Diverse animals communicate using multicomponent signals. How a receiver's central nervous system integrates multiple signal components remains largely unknown. We investigated how female green treefrogs (Hyla cinerea) integrate the multiple spectral components present in male advertisement calls. Typical calls have a bimodal spectrum consisting of formant-like low-frequency (~0.9 kHz) and high-frequency (~2.7 kHz) components that are transduced by different sensory organs in the inner ear. In behavioral experiments, only bimodal calls reliably elicited phonotaxis in no-choice tests, and they were selectively chosen over unimodal calls in two-alternative choice tests. Single neurons in the inferior colliculus of awake, passively listening subjects were classified as combination-insensitive units (27.9%) or combination-sensitive units (72.1%) based on patterns of relative responses to the same bimodal and unimodal calls. Combination-insensitive units responded similarly to the bimodal call and one or both unimodal calls. In contrast, combination-sensitive units exhibited both linear responses (i.e., linear summation) and, more commonly, nonlinear responses (e.g., facilitation, compressive summation, or suppression) to the spectral combination in the bimodal call. These results are consistent with the hypothesis that nonlinearities play potentially critical roles in spectral integration and in the neural processing of multicomponent communication signals.

The Emerging Role of Insulin and Insulin-Like Growth Factor Signaling in Cancer Stem Cells

PubMed Central

Malaguarnera, Roberta; Belfiore, Antonino

2014-01-01

Cancer cells frequently exploit the IGF signaling, a fundamental pathway mediating development, cell growth, and survival. As a consequence, several components of the IGF signaling are deregulated in cancer and sustain cancer progression. However, specific targeting of IGF-IR in humans has resulted efficacious only in small subsets of cancers, making researches wondering whether IGF system targeting is still worth pursuing in the clinical setting. Although no definite answer is yet available, it has become increasingly clear that other components of the IGF signaling pathway, such as IR-A, may substitute for the lack of IGF-IR, and induce cancer resistance and/or clonal selection. Moreover, accumulating evidence now indicates that IGF signaling is a central player in the induction/maintenance of epithelial mesenchymal transition (EMT) and cell stemness, two strictly related programs, which play a key role in metastatic spread and resistance to cancer treatments. Here we review the evidences indicating that IGF signaling enhances the expression of transcription factors implicated in the EMT program and has extensive cross-talk with specific pathways involved in cell pluripotency and stemness maintenance. In turn, EMT and cell stemness activate positive feed-back mechanisms causing up-regulation of various IGF signaling components. These findings may have novel translational implications. PMID:24550888

Comparison of three-dimensional orthodontic load systems of different commercial archwires for space closure

PubMed Central

Gajda, Steven; Chen, Jie

2014-01-01

Objective To experimentally quantify the effects of the loop design on three-dimensional orthodontic load systems of two types of commercial closing loop archwires: Teardrop and Keyhole. Materials and Methods An orthodontic force tester and custom-made dentoform were used to measure the load systems produced on two teeth during simulated space closure. The system included three force components along and three moment components about three clinically defined axes on two target teeth: the left maxillary canine and the lateral incisor. The archwires were attached to the dentoform and were activated following a standard clinical procedure. Results The resulting six load components produced by the two archwires were reported and compared. The results were also compared with those of the T-loop archwire published previously. Conclusions The three designs deliver similar loading patterns; however, the component magnitudes are dependent on the design. All of the designs result in lingual tipping of the teeth, canine lingual-mesial displacement, canine crown-mesial-in rotation, and incisor crown-distal-in rotation. PMID:21879793

Modelling Cosmic-Ray Effects in the Protosolar Disk

NASA Technical Reports Server (NTRS)

Wilson, Thomas L.

2010-01-01

The role that Galactic cosmic rays (GCRs) and solar energetic particles (SEPs) play in the dynamic evolution of protosolar disks and the origin of our Solar System is a fundamental one. The GCRs are an important component of the interstellar medium (ISM), and even play a role in correcting the age determinations of some irons versus CAIs (calcium-aluminum inclusions) in meteoroids . Because CRs also are one of the energy transport mechanisms in a planetary nebula, the question of modelling their effect upon this broad subject is a serious topic for planetary science. The problem is addressed here.

A genome-wide study of two-component signal transduction systems in eight newly sequenced mutans streptococci strains

PubMed Central

2012-01-01

Background Mutans streptococci are a group of gram-positive bacteria including the primary cariogenic dental pathogen Streptococcus mutans and closely related species. Two component systems (TCSs) composed of a signal sensing histidine kinase (HK) and a response regulator (RR) play key roles in pathogenicity, but have not been comparatively studied for these oral bacterial pathogens. Results HKs and RRs of 8 newly sequenced mutans streptococci strains, including S. sobrinus DSM20742, S. ratti DSM20564 and six S. mutans strains, were identified and compared to the TCSs of S. mutans UA159 and NN2025, two previously genome sequenced S. mutans strains. Ortholog analysis revealed 18 TCS clusters (HK-RR pairs), 2 orphan HKs and 2 orphan RRs, of which 8 TCS clusters were common to all 10 strains, 6 were absent in one or more strains, and the other 4 were exclusive to individual strains. Further classification of the predicted HKs and RRs revealed interesting aspects of their putative functions. While TCS complements were comparable within the six S. mutans strains, S. sobrinus DSM20742 lacked TCSs possibly involved in acid tolerance and fructan catabolism, and S. ratti DSM20564 possessed 3 unique TCSs but lacked the quorum-sensing related TCS (ComDE). Selected computational predictions were verified by PCR experiments. Conclusions Differences in the TCS repertoires of mutans streptococci strains, especially those of S. sobrinus and S. ratti in comparison to S. mutans, imply differences in their response mechanisms for survival in the dynamic oral environment. This genomic level study of TCSs should help in understanding the pathogenicity of these mutans streptococci strains. PMID:22475007

The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx): Goals, platforms, and field operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, R.; Springston, S.; Mechoso, C. R.

2011-01-21

The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was an international field program designed to make observations of poorly understood but critical components of the coupled climate system of the southeast Pacific. This region is characterized by strong coastal upwelling, the coolest SSTs in the tropical belt, and is home to the largest subtropical stratocumulus deck on Earth. The field intensive phase of VOCALS-REx took place during October and November 2008 and constitutes a critical part of a broader CLIVAR program (VOCALS) designed to develop and promote scientific activities leading to improved understanding, model simulations, and predictions of the southeastern Pacificmore » (SEP) coupled ocean-atmosphere-land system, on diurnal to interannual timescales. The other major components of VOCALS are a modeling program with a model hierarchy ranging from the local to global scales, and a suite of extended observations from regular research cruises, instrumented moorings, and satellites. The two central themes of VOCALS-REx focus upon (a) links between aerosols, clouds and precipitation and their impacts on marine stratocumulus radiative properties, and (b) physical and chemical couplings between the upper ocean and the lower atmosphere, including the role that mesoscale ocean eddies play. A set of hypotheses designed to be tested with the combined field, monitoring and modeling work in VOCALS is presented here. A further goal of VOCALS-REx is to provide datasets for the evaluation and improvement of large-scale numerical models. VOCALS-REx involved five research aircraft, two ships and two surface sites in northern Chile. We describe the instrument payloads and key mission strategies for these platforms and give a summary of the missions conducted.« less

The contribution of qualitative research in designing a complex intervention for secondary prevention of coronary heart disease in two different healthcare systems.

PubMed

Corrrigan, Mairead; Cupples, Margaret E; Smith, Susan M; Byrne, Molly; Leathem, Claire S; Clerkin, Pauline; Murphy, Andrew W

2006-07-18

Developing complex interventions for testing in randomised controlled trials is of increasing importance in healthcare planning. There is a need for careful design of interventions for secondary prevention of coronary heart disease (CHD). It has been suggested that integrating qualitative research in the development of a complex intervention may contribute to optimising its design but there is limited evidence of this in practice. This study aims to examine the contribution of qualitative research in developing a complex intervention to improve the provision and uptake of secondary prevention of CHD within primary care in two different healthcare systems. In four general practices, one rural and one urban, in Northern Ireland and the Republic of Ireland, patients with CHD were purposively selected. Four focus groups with patients (N = 23) and four with staff (N = 29) informed the development of the intervention by exploring how it could be tailored and integrated with current secondary prevention activities for CHD in the two healthcare settings. Following an exploratory trial the acceptability and feasibility of the intervention were discussed in four focus groups (17 patients) and 10 interviews (staff). The data were analysed using thematic analysis. Integrating qualitative research into the development of the intervention provided depth of information about the varying impact, between the two healthcare systems, of different funding and administrative arrangements, on their provision of secondary prevention and identified similar barriers of time constraints, training needs and poor patient motivation. The findings also highlighted the importance to patients of stress management, the need for which had been underestimated by the researchers. The qualitative evaluation provided depth of detail not found in evaluation questionnaires. It highlighted how the intervention needed to be more practical by minimising administration, integrating role plays into behaviour change training, providing more practical information about stress management and removing self-monitoring of lifestyle change. Qualitative research is integral to developing the design detail of a complex intervention and tailoring its components to address individuals' needs in different healthcare systems. The findings highlight how qualitative research may be a valuable component of the preparation for complex interventions and their evaluation.

RDS-SL VS Communication System

DOE Office of Scientific and Technical Information (OSTI.GOV)

2012-09-12

The RDS-SL VS Communication System is a component of the Radiation Detection System for Strategic, Low-Volume Seaports. Its purpose is to acquire real-time data from radiation portal monitors and cameras, record that data in a database, and make it available to system operators and administrators via a web interface. The software system contains two components: a standalone data acquisition and storage component and an ASP.NETweb application that implements the web interface.

Playing a violent television game affects heart rate variability.

PubMed

Ivarsson, Malena; Anderson, Martin; Akerstedt, Torbjörn; Lindblad, Frank

2009-01-01

To investigate how playing a violent/nonviolent television game during the evening affects sympathetic and parasympathetic reactions during and after playing as well as sleep quality during the night after playing. In total, 19 boys, 12-15 years of age, played television games on two occasions in their homes and participated once without gaming. Heart rate, heart rate variability (HRV) and physical activity were measured during gaming/participating and the night to follow using a portable combined heart rate and movement sensor. A sleep diary and questionnaires about gaming experiences and session-specific experiences were filled in. Criteria for Selection of Games: Violent game involves/rewards direct physical violence (no handguns) against another person, and nonviolent game involves/rewards no violence; same game design ('third-person game'); conducted in the same manner; no differences concerning motor activity; similar sound and light effects; no sexual content, violence against women or racial overtones. During violent (vs. nonviolent) gaming, there was significantly higher activity of the very low frequency component of the HRV and total power. During the night after playing, very low frequency, low frequency and high frequency components were significantly higher during the violent (vs. nonviolent) condition, just as total power. There were no significant differences between the three conditions (violent/nonviolent/no gaming) with respect to an index reflecting subjectively perceived sleep difficulties. Nor was there any difference between violent and nonviolent condition for any single sleep item. Violent gaming induces different autonomic responses in boys compared to nonviolent gaming--during playing and during the following night--suggesting different emotional responses. Subjectively perceived sleep quality is not influenced after a single gaming experience. Future studies should address the development of the autonomic balance after gaming over longer time than a night, physiological adaptation to frequent gaming and potential gender differences.

Characterizing the role benthos plays in large coastal seas and estuaries: A modular approach

USGS Publications Warehouse

Tenore, K.R.; Zajac, R.N.; Terwin, J.; Andrade, F.; Blanton, J.; Boynton, W.; Carey, D.; Diaz, R.; Holland, Austin F.; Lopez-Jamar, E.; Montagna, P.; Nichols, F.; Rosenberg, R.; Queiroga, H.; Sprung, M.; Whitlatch, R.B.

2006-01-01

Ecologists studying coastal and estuarine benthic communities have long taken a macroecological view, by relating benthic community patterns to environmental factors across several spatial scales. Although many general ecological patterns have been established, often a significant amount of the spatial and temporal variation in soft-sediment communities within and among systems remains unexplained. Here we propose a framework that may aid in unraveling the complex influence of environmental factors associated with the different components of coastal systems (i.e. the terrestrial and benthic landscapes, and the hydrological seascape) on benthic communities, and use this information to assess the role played by benthos in coastal ecosystems. A primary component of the approach is the recognition of system modules (e.g. marshes, dendritic systems, tidal rivers, enclosed basins, open bays, lagoons). The modules may differentially interact with key forcing functions (e.g. temperature, salinity, currents) that influence system processes and in turn benthic responses and functions. Modules may also constrain benthic characteristics and related processes within certain ecological boundaries and help explain their overall spatio-temporal variation. We present an example of how benthic community characteristics are related to the modular structure of 14 coastal seas and estuaries, and show that benthic functional group composition is significantly related to the modular structure of these systems. We also propose a framework for exploring the role of benthic communities in coastal systems using this modular approach and offer predictions of how benthic communities may vary depending on the modular composition and characteristics of a coastal system. ?? 2006 Elsevier B.V. All rights reserved.

Creep Behavior of Hafnia and Ytterbium Silicate Environmental Barrier Coating Systems on SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Fox, Dennis S.; Ghosn, Louis J.; Harder, Bryan

2011-01-01

Environmental barrier coatings will play a crucial role in future advanced gas turbine engines because of their ability to significantly extend the temperature capability and stability of SiC/SiC ceramic matrix composite (CMC) engine components, thus improving the engine performance. In order to develop high performance, robust coating systems for engine components, appropriate test approaches simulating operating temperature gradient and stress environments for evaluating the critical coating properties must be established. In this paper, thermal gradient mechanical testing approaches for evaluating creep and fatigue behavior of environmental barrier coated SiC/SiC CMC systems will be described. The creep and fatigue behavior of Hafnia and ytterbium silicate environmental barrier coatings on SiC/SiC CMC systems will be reported in simulated environmental exposure conditions. The coating failure mechanisms will also be discussed under the heat flux and stress conditions.

Stellar populations, stellar masses and the formation of galaxy bulges and discs at z < 3 in CANDELS

NASA Astrophysics Data System (ADS)

Margalef-Bentabol, Berta; Conselice, Christopher J.; Mortlock, Alice; Hartley, Will; Duncan, Kenneth; Kennedy, Rebecca; Kocevski, Dale D.; Hasinger, Guenther

2018-02-01

We present a multicomponent structural analysis of the internal structure of 1074 high-redshift massive galaxies at 1 < z < 3 from the CANDELS HST Survey. In particular, we examine galaxies best fitted by two structural components, and thus likely forming discs and bulges. We examine the stellar mass, star formation rates (SFRs) and colours of both the inner 'bulge' and outer 'disc' components for these systems using Spectral Energy Distribution (SED) information from the resolved ACS+WFC3 HST imaging. We find that the majority of both inner and outer components lie in the star-forming region of UVJ space (68 and 90 per cent, respectively). However, the inner portions, or the likely forming bulges, are dominated by dusty star formation. Furthermore, we show that the outer components of these systems have a higher SFR than their inner regions, and the ratio of SFR between 'disc' and 'bulge' increases at lower redshifts. Despite the higher SFR of the outer component, the stellar mass ratio of inner to outer component remains constant through this epoch. This suggests that there is mass transfer from the outer to inner components for typical two-component-forming systems, thus building bulges from discs. Finally, using Chandra data we find that the presence of an active galactic nucleus is more common in both one-component spheroid-like galaxies and two-component systems (13 ± 3 and 11 ± 2 per cent) than in one-component disc-like galaxies (3 ± 1 per cent), demonstrating that the formation of a central inner component likely triggers the formation of central massive black holes in these galaxies.

Coiled-Coil Antagonism Regulates Activity of Venus Flytrap-Domain-Containing Sensor Kinases of the BvgS Family

PubMed Central

Lesne, Elodie; Dupré, Elian; Lensink, Marc F.; Locht, Camille

2018-01-01

ABSTRACT Bordetella pertussis controls the expression of its virulence regulon through the two-component system BvgAS. BvgS is a prototype for a family of multidomain sensor kinases. In BvgS, helical linkers connect periplasmic Venus flytrap (VFT) perception domains to a cytoplasmic Per-Arnt-Sim (PAS) domain and the PAS domain to the dimerization/histidine phosphotransfer (DHp) domain of the kinase. The two linkers can adopt coiled-coil structures but cannot do so simultaneously. The first linker forms a coiled coil in the kinase mode and the second in the phosphatase mode, with the other linker in both cases showing an increase in dynamic behavior. The intervening PAS domain changes its quaternary structure between the two modes. In BvgS homologues without a PAS domain, a helical “X” linker directly connects the VFT and DHp domains. Here, we used BvgS as a platform to characterize regulation in members of the PAS-less subfamily. BvgS chimeras of homologues with natural X linkers displayed various regulation phenotypes. We identified two distinct coiled-coil registers in the N- and C-terminal portions of the X linkers. Stable coil formation in the C-terminal moiety determines the phosphatase mode, similarly to BvgS; in contrast, coil formation in the N-terminal moiety along the other register leads to the kinase mode. Thus, antagonism between two registers in the VFT-DHp linker forms the basis for activity regulation in the absence of the PAS domain. The N and C moieties of the X linker play roles similar to those played by the two independent linkers in sensor kinases with a PAS domain, providing a unified mechanism of regulation for the entire family. PMID:29487240

Dynamic characteristics of otolith ocular response during counter rotation about dual yaw axes in mice

PubMed Central

Shimizu, Naoki; Wood, Scott; Kushiro, Keisuke; Yanai, Shuichi; Perachio, Adrian; Makishima, Tomoko

2014-01-01

The central vestibular system plays an important role in higher neural functions such as self-motion perception and spatial orientation. Its ability to store head angular velocity is called velocity storage mechanism (VSM), which has been thoroughly investigated across a wide range of species. However, little is known about the mouse VSM, because the mouse lacks typical ocular responses such as optokinetic after nystagmus or a dominant time constant of vestibulo-ocular reflex for which the VSM is critical. Experiments were conducted to examine the otolith-driven eye movements related to the VSM and verify its characteristics in mice. We used a novel approach to generate a similar rotating vector as a traditional off-vertical axis rotation (OVAR) but with a larger resultant gravito-inertial force (>1 g) by using counter rotation centrifugation. Similar to results previously described in other animals during OVAR, two components of eye movements were induced, i.e. a sinusoidal modulatory eye movement (modulation component) on which a unidirectional nystagmaus (bias component) was superimposed. Each response is considered to derive from different mechanisms; modulations arise predominantly through linear vestibulo-ocular reflex, whereas for the bias, the VSM is responsible. Data indicate that the mouse also has a well-developed vestibular system through otoliths inputs, showing its highly conserved nature across mammalian species. On the other hand, to reach a plateau state of bias, a higher frequency rotation or a larger gravito-inertial force was considered to be necessary than other larger animals. Compared with modulation, the bias had a more variable profile, suggesting an inherent complexity of higher-order neural processes in the brain. Our data provides the basis for further study of the central vestibular system in mice, however, the underlying individual variability should be taken into consideration. PMID:25446357

DAISY-DAMP: A distributed AI system for the dynamic allocation and management of power

NASA Technical Reports Server (NTRS)

Hall, Steven B.; Ohler, Peter C.

1988-01-01

One of the critical parameters that must be addressed when designing a loosely coupled Distributed AI SYstem (DAISY) has to do with the degree to which authority is centralized or decentralized. The decision to implement the Dynamic Allocation and Management of Power (DAMP) system as a network of cooperating agents mandated this study. The DAISY-DAMP problem is described; the component agents of the system are characterized; and the communication protocols system elucidated. The motivations and advantages in designing the system with authority decentralized is discussed. Progress in the area of Speech Act theory is proposed as playing a role in constructing decentralized systems.

Many-body physics in two-component Bose–Einstein condensates in a cavity: fragmented superradiance and polarization

NASA Astrophysics Data System (ADS)

Lode, Axel U. J.; Diorico, Fritz S.; Wu, RuGway; Molignini, Paolo; Papariello, Luca; Lin, Rui; Lévêque, Camille; Exl, Lukas; Tsatsos, Marios C.; Chitra, R.; Mauser, Norbert J.

2018-05-01

We consider laser-pumped one-dimensional two-component bosons in a parabolic trap embedded in a high-finesse optical cavity. Above a threshold pump power, the photons that populate the cavity modify the effective atom trap and mediate a coupling between the two components of the Bose–Einstein condensate. We calculate the ground state of the laser-pumped system and find different stages of self-organization depending on the power of the laser. The modified potential and the laser-mediated coupling between the atomic components give rise to rich many-body physics: an increase of the pump power triggers a self-organization of the atoms while an even larger pump power causes correlations between the self-organized atoms—the BEC becomes fragmented and the reduced density matrix acquires multiple macroscopic eigenvalues. In this fragmented superradiant state, the atoms can no longer be described as two-level systems and the mapping of the system to the Dicke model breaks down.

Kinetics of homogeneous nucleation on many-component systems

NASA Technical Reports Server (NTRS)

Hirschfelder, J. O.

1974-01-01

Reiss's (1950) classical treatment of the kinetics of homogeneous nucleation in a system containing two chemical components is extended to many-component systems. The formulation is analogous to the pseudostationary-state theory of chemical reaction rates, with the free energy as a function of the composition of the embryo taking the place of the potential energy as a function of interatomic distances.

Kinetics of homogeneous nucleation in many component systems

NASA Technical Reports Server (NTRS)

Hirschfelder, J. O.

1974-01-01

Reiss's classical treatment of the kinetics of homogeneous nucleation in a system containing two chemical components is extended to many-component systems. The formulation is analogous to the pseudo-stationary state theory of chemical reaction rates with the free energy as a function of the composition of the embryo taking the place of the potential energy as a function of interatomic distances.

Casual Games and Casual Learning About Human Biological Systems

NASA Astrophysics Data System (ADS)

Price, C. Aaron; Gean, Katherine; Christensen, Claire G.; Beheshti, Elham; Pernot, Bryn; Segovia, Gloria; Person, Halcyon; Beasley, Steven; Ward, Patricia

2016-02-01

Casual games are everywhere. People play them throughout life to pass the time, to engage in social interactions, and to learn. However, their simplicity and use in distraction-heavy environments can attenuate their potential for learning. This experimental study explored the effects playing an online, casual game has on awareness of human biological systems. Two hundred and forty-two children were given pretests at a Museum and posttests at home after playing either a treatment or control game. Also, 41 children were interviewed to explore deeper meanings behind the test results. Results show modest improvement in scientific attitudes, ability to identify human biological systems and in the children's ability to describe how those systems work together in real-world scenarios. Interviews reveal that children drew upon their prior school learning as they played the game. Also, on the surface they perceived the game as mainly entertainment but were easily able to discern learning outcomes when prompted. Implications for the design of casual games and how they can be used to enhance transfer of knowledge from the classroom to everyday life are discussed.

The Prediction of Key Cytoskeleton Components Involved in Glomerular Diseases Based on a Protein-Protein Interaction Network.

PubMed

Ding, Fangrui; Tan, Aidi; Ju, Wenjun; Li, Xuejuan; Li, Shao; Ding, Jie

2016-01-01

Maintenance of the physiological morphologies of different types of cells and tissues is essential for the normal functioning of each system in the human body. Dynamic variations in cell and tissue morphologies depend on accurate adjustments of the cytoskeletal system. The cytoskeletal system in the glomerulus plays a key role in the normal process of kidney filtration. To enhance the understanding of the possible roles of the cytoskeleton in glomerular diseases, we constructed the Glomerular Cytoskeleton Network (GCNet), which shows the protein-protein interaction network in the glomerulus, and identified several possible key cytoskeletal components involved in glomerular diseases. In this study, genes/proteins annotated to the cytoskeleton were detected by Gene Ontology analysis, and glomerulus-enriched genes were selected from nine available glomerular expression datasets. Then, the GCNet was generated by combining these two sets of information. To predict the possible key cytoskeleton components in glomerular diseases, we then examined the common regulation of the genes in GCNet in the context of five glomerular diseases based on their transcriptomic data. As a result, twenty-one cytoskeleton components as potential candidate were highlighted for consistently down- or up-regulating in all five glomerular diseases. And then, these candidates were examined in relation to existing known glomerular diseases and genes to determine their possible functions and interactions. In addition, the mRNA levels of these candidates were also validated in a puromycin aminonucleoside(PAN) induced rat nephropathy model and were also matched with existing Diabetic Nephropathy (DN) transcriptomic data. As a result, there are 15 of 21 candidates in PAN induced nephropathy model were consistent with our predication and also 12 of 21 candidates were matched with differentially expressed genes in the DN transcriptomic data. By providing a novel interaction network and prediction, GCNet contributes to improving the understanding of normal glomerular function and will be useful for detecting target cytoskeleton molecules of interest that may be involved in glomerular diseases in future studies.

The Prediction of Key Cytoskeleton Components Involved in Glomerular Diseases Based on a Protein-Protein Interaction Network

PubMed Central

Ju, Wenjun; Li, Xuejuan; Li, Shao; Ding, Jie

2016-01-01

Maintenance of the physiological morphologies of different types of cells and tissues is essential for the normal functioning of each system in the human body. Dynamic variations in cell and tissue morphologies depend on accurate adjustments of the cytoskeletal system. The cytoskeletal system in the glomerulus plays a key role in the normal process of kidney filtration. To enhance the understanding of the possible roles of the cytoskeleton in glomerular diseases, we constructed the Glomerular Cytoskeleton Network (GCNet), which shows the protein-protein interaction network in the glomerulus, and identified several possible key cytoskeletal components involved in glomerular diseases. In this study, genes/proteins annotated to the cytoskeleton were detected by Gene Ontology analysis, and glomerulus-enriched genes were selected from nine available glomerular expression datasets. Then, the GCNet was generated by combining these two sets of information. To predict the possible key cytoskeleton components in glomerular diseases, we then examined the common regulation of the genes in GCNet in the context of five glomerular diseases based on their transcriptomic data. As a result, twenty-one cytoskeleton components as potential candidate were highlighted for consistently down- or up-regulating in all five glomerular diseases. And then, these candidates were examined in relation to existing known glomerular diseases and genes to determine their possible functions and interactions. In addition, the mRNA levels of these candidates were also validated in a puromycin aminonucleoside(PAN) induced rat nephropathy model and were also matched with existing Diabetic Nephropathy (DN) transcriptomic data. As a result, there are 15 of 21 candidates in PAN induced nephropathy model were consistent with our predication and also 12 of 21 candidates were matched with differentially expressed genes in the DN transcriptomic data. By providing a novel interaction network and prediction, GCNet contributes to improving the understanding of normal glomerular function and will be useful for detecting target cytoskeleton molecules of interest that may be involved in glomerular diseases in future studies. PMID:27227331

Why Does Behavioral Instruction Work? A Component Analysis of Performance and Motivational Outcomes.

ERIC Educational Resources Information Center

Omelich, Carol L.; Covington, Martin V.

Two fundamental components of behavioral instruction were investigated: the reported testing feature and absolute performance standards. The component analysis was conducted by offering an undergraduate psychology course simultaneously along two dimensions: grading systems and number of study/test cycles. The 425 college student subjects were…

A combination strategy for extraction and isolation of multi-component natural products by systematic two-phase solvent extraction-(13)C nuclear magnetic resonance pattern recognition and following conical counter-current chromatography separation: Podophyllotoxins and flavonoids from Dysosma versipellis (Hance) as examples.

PubMed

Yang, Zhi; Wu, Youqian; Wu, Shihua

2016-01-29

Despite of substantial developments of extraction and separation techniques, isolation of natural products from natural resources is still a challenging task. In this work, an efficient strategy for extraction and isolation of multi-component natural products has been successfully developed by combination of systematic two-phase liquid-liquid extraction-(13)C NMR pattern recognition and following conical counter-current chromatography separation. A small-scale crude sample was first distributed into 9 systematic hexane-ethyl acetate-methanol-water (HEMWat) two-phase solvent systems for determination of the optimum extraction solvents and partition coefficients of the prominent components. Then, the optimized solvent systems were used in succession to enrich the hydrophilic and lipophilic components from the large-scale crude sample. At last, the enriched components samples were further purified by a new conical counter-current chromatography (CCC). Due to the use of (13)C NMR pattern recognition, the kinds and structures of major components in the solvent extracts could be predicted. Therefore, the method could collect simultaneously the partition coefficients and the structural information of components in the selected two-phase solvents. As an example, a cytotoxic extract of podophyllotoxins and flavonoids from Dysosma versipellis (Hance) was selected. After the systematic HEMWat system solvent extraction and (13)C NMR pattern recognition analyses, the crude extract of D. versipellis was first degreased by the upper phase of HEMWat system (9:1:9:1, v/v), and then distributed in the two phases of the system of HEMWat (2:8:2:8, v/v) to obtain the hydrophilic lower phase extract and lipophilic upper phase extract, respectively. These extracts were further separated by conical CCC with the HEMWat systems (1:9:1:9 and 4:6:4:6, v/v). As results, total 17 cytotoxic compounds were isolated and identified. In general, whole results suggested that the strategy was very efficient for the systematic extraction and isolation of biological active components from the complex biomaterials. Copyright © 2016 Elsevier B.V. All rights reserved.

Laboratory models for central nervous system tumor stem cell research.

PubMed

Khan, Imad Saeed; Ehtesham, Moneeb

2015-01-01

Central nervous system (CNS) tumors are complex organ systems comprising of a neoplastic component with associated vasculature, inflammatory cells, and reactive cellular and extracellular components. Research has identified a subset of cells in CNS tumors that portray defining properties of neural stem cells, namely, that of self-renewal and multi-potency. Growing evidence suggests that these tumor stem cells (TSC) play an important role in the maintenance and growth of the tumor. Furthermore, these cells have also been shown to be refractory to conventional therapy and may be crucial for tumor recurrence and metastasis. Current investigations are focusing on isolating these TSC from CNS tumors to investigate their unique biological processes. This understanding will help identify and develop more effective and comprehensive treatment strategies. This chapter provides an overview of some of the most commonly used laboratory models for CNSTSC research.

Model-Based Sensor Placement for Component Condition Monitoring and Fault Diagnosis in Fossil Energy Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mobed, Parham; Pednekar, Pratik; Bhattacharyya, Debangsu

Design and operation of energy producing, near “zero-emission” coal plants has become a national imperative. This report on model-based sensor placement describes a transformative two-tier approach to identify the optimum placement, number, and type of sensors for condition monitoring and fault diagnosis in fossil energy system operations. The algorithms are tested on a high fidelity model of the integrated gasification combined cycle (IGCC) plant. For a condition monitoring network, whether equipment should be considered at a unit level or a systems level depends upon the criticality of the process equipment, its likeliness to fail, and the level of resolution desiredmore » for any specific failure. Because of the presence of a high fidelity model at the unit level, a sensor network can be designed to monitor the spatial profile of the states and estimate fault severity levels. In an IGCC plant, besides the gasifier, the sour water gas shift (WGS) reactor plays an important role. In view of this, condition monitoring of the sour WGS reactor is considered at the unit level, while a detailed plant-wide model of gasification island, including sour WGS reactor and the Selexol process, is considered for fault diagnosis at the system-level. Finally, the developed algorithms unify the two levels and identifies an optimal sensor network that maximizes the effectiveness of the overall system-level fault diagnosis and component-level condition monitoring. This work could have a major impact on the design and operation of future fossil energy plants, particularly at the grassroots level where the sensor network is yet to be identified. In addition, the same algorithms developed in this report can be further enhanced to be used in retrofits, where the objectives could be upgrade (addition of more sensors) and relocation of existing sensors.« less

Pragmatic Language Outcomes of Children With Attention Deficit Hyperactivity Disorder After Therapist- and Parent-Delivered Play-Based Interventions: Two One-Group Pretest-Posttest Studies With a Longitudinal Component.

PubMed

Wilkes-Gillan, Sarah; Munro, Natalie; Cordier, Reinie; Cantrill, Alycia; Pearce, Wendy

The pragmatic language outcomes of children with attention deficit hyperactivity disorder (ADHD) were explored across two feasibility studies. Five children with ADHD (ages 6-11 yr), their parents, and 5 typically developing peers completed an assessment 18 mo after a therapist-delivered intervention (Study 1). Participants then completed a parent-delivered intervention (Study 2). Blinded ratings of peer-to-peer play interactions documented changes in children's pragmatic language 18 mo after the Study 1 intervention and before, immediately after, and 1 mo after the Study 2 intervention. Nonparametric statistics and Cohen's d were used to measure change. Children's pragmatic language outcomes were maintained 18 mo after the therapist-delivered intervention and significantly improved from before to 1 mo after the parent-delivered intervention. Interventions involving occupational therapist and speech-language pathologist collaboration, play, and parent and peer involvement may facilitate children's pragmatic language skills. Copyright © 2017 by the American Occupational Therapy Association, Inc.

Solitons of the coupled Schrödinger-Korteweg-de Vries system with arbitrary strengths of the nonlinearity and dispersion

NASA Astrophysics Data System (ADS)

Gromov, Evgeny; Malomed, Boris

2017-11-01

New two-component soliton solutions of the coupled high-frequency (HF)—low-frequency (LF) system, based on Schrödinger-Korteweg-de Vries (KdV) system with the Zakharov's coupling, are obtained for arbitrary relative strengths of the nonlinearity and dispersion in the LF component. The complex HF field is governed by the linear Schrödinger equation with a potential generated by the real LF component, which, in turn, is governed by the KdV equation including the ponderomotive coupling term, representing the feedback of the HF field onto the LF component. First, we study the evolution of pulse-shaped pulses by means of direct simulations. In the case when the dispersion of the LF component is weak in comparison to its nonlinearity, the input gives rise to several solitons in which the HF component is much broader than its LF counterpart. In the opposite case, the system creates a single soliton with approximately equal widths of both components. Collisions between stable solitons are studied too, with a conclusion that the collisions are inelastic, with a greater soliton getting still stronger, and the smaller one suffering further attenuation. Robust intrinsic modes are excited in the colliding solitons. A new family of approximate analytical two-component soliton solutions with two free parameters is found for an arbitrary relative strength of the nonlinearity and dispersion of the LF component, assuming weak feedback of the HF field onto the LF component. Further, a one-parameter (non-generic) family of exact bright-soliton solutions, with mutually proportional HF and LF components, is produced too. Intrinsic dynamics of the two-component solitons, induced by a shift of their HF component against the LF one, is also studied, by means of numerical simulations, demonstrating excitation of a robust intrinsic mode. In addition to the above-mentioned results for LF-dominated two-component solitons, which always run in one (positive) velocities, we produce HF-dominated soliton complexes, which travel in the opposite (negative) direction. They are obtained in a numerical form and by means of a quasi-adiabatic analytical approximation. The solutions with positive and negative velocities correspond, respectively, to super- and subsonic Davydov-Scott solitons.

Flow pumping system for physiological waveforms.

PubMed

Tsai, William; Savaş, Omer

2010-02-01

A pulsatile flow pumping system is developed to replicate flow waveforms with reasonable accuracy for experiments simulating physiological blood flows at numerous points in the body. The system divides the task of flow waveform generation between two pumps: a gear pump generates the mean component and a piston pump generates the oscillatory component. The system is driven by two programmable servo controllers. The frequency response of the system is used to characterize its operation. The system has been successfully tested in vascular flow experiments where sinusoidal, carotid, and coronary flow waveforms are replicated.

Combined Thermomechanical and Environmental Durability of Environmental Barrier Coating Systems on SiC/SiC Ceramic Matrix Composites

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Harder, Bryan; Bhatt, Ramakrishna

2016-01-01

Environmental barrier coatings (EBCs) and SiC/SiC ceramic matrix composites (CMCs) will play a crucial role in next generation turbine engines for hot-section component applications. The development of prime-reliant environmental barrier coatings is essential to the EBC-CMC system durability, ensuring the successful implementations of the high temperature and lightweight engine component technologies for engine applications.This paper will emphasize recent NASA environmental barrier coating and CMC developments for SiC/SiC turbine airfoil components, utilizing advanced coating compositions and processing methods. The emphasis has been particularly placed on thermomechanical and environment durability evaluations of EBC-CMC systems. We have also addressed the integration of the EBCs with advanced SiC/SiC CMCs, and studied the effects of combustion environments and Calcium-Magnesium-Alumino-Silicate (CMAS) deposits on the durability of the EBC-CMC systems under thermal gradient and mechanical loading conditions. Advanced environmental barrier coating systems, including multicomponent rare earth silicate EBCs and HfO2-Si based bond coats, will be discussed for the performance improvements to achieve better temperature capability and CMAS resistance for future engine operating conditions.

A Systems Approach to the Physiology of Weightlessness

NASA Technical Reports Server (NTRS)

White, Ronald J.; Leonard, Joel I.; Rummel, John A.; Leach, Carolyn S.

1991-01-01

A systems approach to the unraveling of the complex response pattern of the human subjected to weightlessness is presented. The major goal of this research is to obtain an understanding of the role that each of the major components of the human system plays following the transition to and from space. The cornerstone of this approach is the utilization of a variety of mathematical models in order to pose and test alternative hypotheses concerned with the adaptation process. An integrated hypothesis for the human physiological response to weightlessness is developed.

A systems approach to the physiology of weightlessness

NASA Technical Reports Server (NTRS)

White, Ronald J.; Leonard, Joel I.; Rummel, John A.; Leach, Carolyn S.

1991-01-01

A general systems approach to conducting and analyzing research on the human adaptation to weightlessness is presented. The research is aimed at clarifying the role that each of the major components of the human system plays following the transition to and from space. The approach utilizes a variety of mathematical models in order to pose and test alternative hypotheses concerned with the adaptation process. Certain aspects of the problem of fluid and electrolyte shifts in weightlessnes are considered, and an integrated hypothesis based on numerical simulation studies and experimental data is presented.

Coherent gradient sensing method and system for measuring surface curvature

NASA Technical Reports Server (NTRS)

Rosakis, Ares J. (Inventor); Moore, Jr., Nicholas R. (Inventor); Singh, Ramen P. (Inventor); Kolawa, Elizabeth (Inventor)

2000-01-01

A system and method for determining a curvature of a specularly reflective surface based on optical interference. Two optical gratings are used to produce a spatial displacement in an interference field of two different diffraction components produced by one grating from different diffraction components produced by another grating. Thus, the curvature of the surface can be determined.

Advanced Simulation in Undergraduate Pilot Training: Systems Integration. Final Report (February 1972-March 1975).

ERIC Educational Resources Information Center

Larson, D. F.; Terry, C.

The Advanced Simulator for Undergraduate Pilot Training (ASUPT) was designed to investigate the role of simulation in the future Undergraduate Pilot Training (UPT) program. The problem addressed in this report was one of integrating two unlike components into one synchronized system. These two components were the Basic T-37 Simulators and their…

Analysis of the activity and regulon of the two-component regulatory system encoded by Cjj1484 and Cjj1483 of Campylobacter jejuni

USDA-ARS?s Scientific Manuscript database

Campylobacter jejuni is a leading cause of bacterial diarrheal disease throughout the world and a frequent commensal in the intestinal tract of poultry and many other animals. For maintaining optimal growth and ability to colonize various hosts, C. jejuni depends upon two-component regulatory system...

Development of a simultaneous SANS / FTIR measuring system and its application to polymer cocrystals

NASA Astrophysics Data System (ADS)

Kaneko, F.; Seto, N.; Sato, S.; Radulescu, A.; Schiavone, M. M.; Allgaier, J.; Ute, K.

2016-09-01

In order to provide plenty of structure information which would assist in the analysis and interpretation of small angle neutron scattering (SANS) profile, a novel method for the simultaneous time-resolved measurement of SANS and Fourier transform infrared (FTIR) spectroscopy has been developed. The method was realized by building a device consisting of a portable FTIR spectrometer and an optical system equipped with two aluminum coated quartz plates that are fully transparent to neutron beams but play as mirrors for infrared radiation. The optical system allows both a neutron beam and an infrared beam pass through the same position of a test specimen coaxially. The device was installed on a small angle neutron diffractometer, KWS2 of the Jülich Centre for Neutron Science (JCNS) outstation at Heinz Maier-Leibnitz Center (MLZ) in Garching, Germany. In order to check the performance of this simultaneous measuring system, the structural changes in the cocrystals of syndiotactic polystyrene during the course of heating were followed. It has been confirmed that FTIR spectra measured in parallel are able to provide information about the behavior of each component and also useful to grasp in real time what is actually happening in the sample system.

Giant gain from spontaneously generated coherence in Y-type double quantum dot structure

NASA Astrophysics Data System (ADS)

Al-Nashy, B.; Razzaghi, Sonia; Al-Musawi, Muwaffaq Abdullah; Rasooli Saghai, H.; Al-Khursan, Amin H.

A theoretical model was presented for linear susceptibility using density matrix theory for Y-configuration of double quantum dots (QDs) system including spontaneously generated coherence (SGC). Two SGC components are included for this system: V, and Λ subsystems. It is shown that at high V-component, the system have a giga gain. At low Λ-system component; it is possible to controls the light speed between superluminal and subluminal using one parameter by increasing SGC component of the V-system. This have applications in quantum information storage and spatially-varying temporal clock.

A new flexible plug and play scheme for modeling, simulating, and predicting gastric emptying

PubMed Central

2014-01-01

Background In-silico models that attempt to capture and describe the physiological behavior of biological organisms, including humans, are intrinsically complex and time consuming to build and simulate in a computing environment. The level of detail of description incorporated in the model depends on the knowledge of the system’s behavior at that level. This knowledge is gathered from the literature and/or improved by knowledge obtained from new experiments. Thus model development is an iterative developmental procedure. The objective of this paper is to describe a new plug and play scheme that offers increased flexibility and ease-of-use for modeling and simulating physiological behavior of biological organisms. Methods This scheme requires the modeler (user) first to supply the structure of the interacting components and experimental data in a tabular format. The behavior of the components described in a mathematical form, also provided by the modeler, is externally linked during simulation. The advantage of the plug and play scheme for modeling is that it requires less programming effort and can be quickly adapted to newer modeling requirements while also paving the way for dynamic model building. Results As an illustration, the paper models the dynamics of gastric emptying behavior experienced by humans. The flexibility to adapt the model to predict the gastric emptying behavior under varying types of nutrient infusion in the intestine (ileum) is demonstrated. The predictions were verified with a human intervention study. The error in predicting the half emptying time was found to be less than 6%. Conclusions A new plug-and-play scheme for biological systems modeling was developed that allows changes to the modeled structure and behavior with reduced programming effort, by abstracting the biological system into a network of smaller sub-systems with independent behavior. In the new scheme, the modeling and simulation becomes an automatic machine readable and executable task. PMID:24917054

Human performance under two different command and control paradigms.

PubMed

Walker, Guy H; Stanton, Neville A; Salmon, Paul M; Jenkins, Daniel P

2014-05-01

The paradoxical behaviour of a new command and control concept called Network Enabled Capability (NEC) provides the motivation for this paper. In it, a traditional hierarchical command and control organisation was pitted against a network centric alternative on a common task, played thirty times, by two teams. Multiple regression was used to undertake a simple form of time series analysis. It revealed that whilst the NEC condition ended up being slightly slower than its hierarchical counterpart, it was able to balance and optimise all three of the performance variables measured (task time, enemies neutralised and attrition). From this it is argued that a useful conceptual response is not to consider NEC as an end product comprised of networked computers and standard operating procedures, nor to regard the human system interaction as inherently stable, but rather to view it as a set of initial conditions from which the most adaptable component of all can be harnessed: the human. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Brief Note :Variability in the cathelicidin 6 (CATHL-6) gene in Tianzhu white yak from Tibetan area in China.

PubMed

E, G X; Na, R S; Zhao, Y J; Chen, L P; Qiu, X Y; Huang, Y F

2015-04-10

Cathelicidins are a major family of antimicrobial peptides (AMPs), an important component of innate immune system, playing a critical role in host defense and disease resistance in virtually all living species. Polymorphism and functional studies on cathelicidin of Tianzhu white yak contribute to understanding the specific innate immune mechanism in animals living at high altitudes in comparison to cattle and domesticated white yak. Thirty-six individuals of Tianzhu white yak, originating from the area of three ecotypes (Gansu in China), were investigated. The total length of the aligned Yak cathelicidin 6 (CATHL-6) sequences was 1923 bp, including six single nucleotide polymorphisms and one indel. Ten haplotypes were identified, and phylogenetic analyses resolved those 10 haplotypes in two clusters. The results indicate that the white yak originated from two domestication sites. In addition, lack of significant pairwise difference between sequences (Tajima's D = 0.92865, P > 0.10) in the CATHL-6 region indicates absence of population size expansion in current white yak population.

Basic components of connective tissues and extracellular matrix: elastin, fibrillin, fibulins, fibrinogen, fibronectin, laminin, tenascins and thrombospondins.

PubMed

Halper, Jaroslava; Kjaer, Michael

2014-01-01

Collagens are the most abundant components of the extracellular matrix and many types of soft tissues. Elastin is another major component of certain soft tissues, such as arterial walls and ligaments. Many other molecules, though lower in quantity, function as essential components of the extracellular matrix in soft tissues. Some of these are reviewed in this chapter. Besides their basic structure, biochemistry and physiology, their roles in disorders of soft tissues are discussed only briefly as most chapters in this volume deal with relevant individual compounds. Fibronectin with its muldomain structure plays a role of "master organizer" in matrix assembly as it forms a bridge between cell surface receptors, e.g., integrins, and compounds such collagen, proteoglycans and other focal adhesion molecules. It also plays an essential role in the assembly of fibrillin-1 into a structured network. Laminins contribute to the structure of the extracellular matrix (ECM) and modulate cellular functions such as adhesion, differentiation, migration, stability of phenotype, and resistance towards apoptosis. Though the primary role of fibrinogen is in clot formation, after conversion to fibrin by thrombin, it also binds to a variety of compounds, particularly to various growth factors, and as such fibrinogen is a player in cardiovascular and extracellular matrix physiology. Elastin, an insoluble polymer of the monomeric soluble precursor tropoelastin, is the main component of elastic fibers in matrix tissue where it provides elastic recoil and resilience to a variety of connective tissues, e.g., aorta and ligaments. Elastic fibers regulate activity of TGFβs through their association with fibrillin microfibrils. Elastin also plays a role in cell adhesion, cell migration, and has the ability to participate in cell signaling. Mutations in the elastin gene lead to cutis laxa. Fibrillins represent the predominant core of the microfibrils in elastic as well as non-elastic extracellular matrixes, and interact closely with tropoelastin and integrins. Not only do microfibrils provide structural integrity of specific organ systems, but they also provide a scaffold for elastogenesis in elastic tissues. Fibrillin is important for the assembly of elastin into elastic fibers. Mutations in the fibrillin-1 gene are closely associated with Marfan syndrome. Fibulins are tightly connected with basement membranes, elastic fibers and other components of extracellular matrix and participate in formation of elastic fibers. Tenascins are ECM polymorphic glycoproteins found in many connective tissues in the body. Their expression is regulated by mechanical stress both during development and in adulthood. Tenascins mediate both inflammatory and fibrotic processes to enable effective tissue repair and play roles in pathogenesis of Ehlers-Danlos, heart disease, and regeneration and recovery of musculo-tendinous tissue. One of the roles of thrombospondin 1 is activation of TGFβ. Increased expression of thrombospondin and TGFβ activity was observed in fibrotic skin disorders such as keloids and scleroderma. Cartilage oligomeric matrix protein (COMP) or thrombospondin-5 is primarily present in the cartilage. High levels of COMP are present in fibrotic scars and systemic sclerosis of the skin, and in tendon, especially with physical activity, loading and post-injury. It plays a role in vascular wall remodeling and has been found in atherosclerotic plaques as well.

Experimental characterization of novel microdiffuser elements

NASA Astrophysics Data System (ADS)

Ehrlich, L.; Punch, J.; Jeffers, N.; Stafford, J.

2014-07-01

Micropumps can play a significant role in thermal management applications, as a component of microfluidic cooling systems. For next-generation high density optical communication systems, in particular, heat flux levels are sufficiently high to require a microfluidic circuit for cooling. Valveless piezoelectrically-actuated micropumps are a particularly promising technology to be deployed for this application. These pumps exploit the asymmetric flow behaviour of microdiffusers to achieve net flow. They feature no rotating or contacting parts, which make them intrinsically reliable in comparison to micropumps with active valves. In this paper, two novel microdiffuser elements are reported and characterized. The micropumps were fabricated using a 3D Printer. Each single diffuser had a length of 1800 pm and a depth of 400 pm. An experimental characterization was conducted in which the flow rate and differential pressure were measured as a function of operating frequency. In comparison with standard diffuser, both elements showed an increase in differential pressure in the range of 40 - 280 %, but only one of the elements exhibited an improved flow rate, of about 85 %.

Modelling and Bibliotherapy as Tools to Enhance Pro-Social Interactions during English Language Arts Lessons with First Graders

ERIC Educational Resources Information Center

Nguyen, Neal; Lyons, Catherine; Gelfer, Jeff; Leytham, Patrick; Nelson, Leslie; Krasch, Delilah; O'Hara, Katie

2016-01-01

Play is one of the essential components in proper development of first-grade students. Since the adoption by various states of the Common Core State Standards (CCSS), two outcomes have developed: (a) increased instructional time and (b) decreased public school recess periods across school districts. Given the complex nature of daily instructional…

Phonological and Executive Working Memory in L2 Task-Based Speech Planning and Performance

ERIC Educational Resources Information Center

Wen, Zhisheng

2016-01-01

The present study sets out to explore the distinctive roles played by two working memory (WM) components in various aspects of L2 task-based speech planning and performance. A group of 40 post-intermediate proficiency level Chinese EFL learners took part in the empirical study. Following the tenets and basic principles of the…

The Contribution of "Cool" and "Hot" Components of Decision-Making in Adolescence: Implications for Developmental Psychopathology

ERIC Educational Resources Information Center

Seguin, Jean R.; Arseneault, Louise; Tremblay, Richard E.

2007-01-01

Impairments in either "cool" or "hot" processes may represent two pathways to deficient decision-making. Whereas cool processes are associated with cognitive and rational decisions, hot processes are associated with emotional, affective, and visceral processes. In this study, 168 boys were administered a card-playing task at ages 13 and 14 years…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sparks, W.E. Jr.

One of Exxon`s goals is to pursue the highest quality exploration opportunities worldwide. To accomplish this goal, we use an approach that allows us to systematically compare the different exploration areas worldwide in order to identify and focus on the highest quality basins and plays, prioritize investment opportunities that are identified in these areas, and allocate our resources appropriately. The process begins with the development of a list of basins that are ranked according to their assessed undiscovered potential and the geotechnical characteristics of their hydrocarbon systems. This basin scale seriatim or rank list is then used to identify themore » highest quality {open_quotes}focus{close_quotes} plays within the higher potential basins and hydrocarbon systems. The ranked list of basins and plays becomes the foundation for development of an {open_quotes}Opportunity Seriatim.{close_quotes} There are three principal components incorporated into Exxon`s Opportunity Seriatim: (1) Geotechnical appraisal - How good is the resource?, (2) Accessibility - Can we or will we be able to access the resource?, and (3) Economics - will we make an acceptable profit if we access the resource? After these components are considered, additional adjustments are made to the Opportunity Seriatim. The Opportunity Seriatim is then used to develop strategies which are globally consistent to build and maintain a broad portfolio of the highest quality opportunities, and finally, to select the best quality prospects in our highest quality plays for funding. Prospects are selected based on risk vs. reward ratio, drilling commitments, and appropriate economic yardsticks. Using this process, Exxon has steadily improved its exploration performance. Over the last ten years, the volume of reserves Exxon discovers has increased, our drilling success rate has improved substantially, and our finding costs have continued to fall.« less

NASA's Earth Science Data Systems

NASA Technical Reports Server (NTRS)

Ramapriyan, H. K.

2015-01-01

NASA's Earth Science Data Systems (ESDS) Program has evolved over the last two decades, and currently has several core and community components. Core components provide the basic operational capabilities to process, archive, manage and distribute data from NASA missions. Community components provide a path for peer-reviewed research in Earth Science Informatics to feed into the evolution of the core components. The Earth Observing System Data and Information System (EOSDIS) is a core component consisting of twelve Distributed Active Archive Centers (DAACs) and eight Science Investigator-led Processing Systems spread across the U.S. The presentation covers how the ESDS Program continues to evolve and benefits from as well as contributes to advances in Earth Science Informatics.

The social play, social skills and parent-child relationships of children with ADHD 12 months following a RCT of a play-based intervention.

PubMed

Barnes, Gabrielle; Wilkes-Gillan, Sarah; Bundy, Anita; Cordier, Reinie

2017-12-01

There is an urgent need to investigate the long-term impact of social skill interventions for children with attention deficit hyperactivity disorder (ADHD). Interventions targeting the social skills of children with ADHD have limited short-term effectiveness and rarely investigate the long-term impact. Furthermore, these interventions are most frequently conducted in the clinic setting, without including the child's natural settings and interactants, such as their regular playmates and parents. The present study investigated the social play, social skills and parent-child relationships of children with ADHD and their playmates (n = 13/group) aged 5-13 years. A two-group before and after design with a longitudinal component was applied. Participant data compared over two time points, immediately following a randomised, controlled trial (RCT) of a play-based intervention and 12 months post-RCT. From immediately following the RCT to the 12-month follow-up, children with ADHD maintained social play skill gains in the home environment. Playmates maintained social play skill gains across the home and clinic environments. Children scored within a developmentally appropriate range, falling within 1 standard deviation of the mean for social skills and most parent-child relationship scales using norm-based assessments. Results support the long-term effectiveness of the intervention. © 2017 Occupational Therapy Australia.

Simple waves in a two-component Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Ivanov, S. K.; Kamchatnov, A. M.

2018-04-01

We study the dynamics of so-called simple waves in a two-component Bose-Einstein condensate. The evolution of the condensate is described by Gross-Pitaevskii equations which can be reduced for these simple wave solutions to a system of ordinary differential equations which coincide with those derived by Ovsyannikov for the two-layer fluid dynamics. We solve the Ovsyannikov system for two typical situations of large and small difference between interspecies and intraspecies nonlinear interaction constants. Our analytic results are confirmed by numerical simulations.

Estimation procedures to measure and monitor failure rates of components during thermal-vacuum testing

NASA Technical Reports Server (NTRS)

Williams, R. E.; Kruger, R.

1980-01-01

Estimation procedures are described for measuring component failure rates, for comparing the failure rates of two different groups of components, and for formulating confidence intervals for testing hypotheses (based on failure rates) that the two groups perform similarly or differently. Appendix A contains an example of an analysis in which these methods are applied to investigate the characteristics of two groups of spacecraft components. The estimation procedures are adaptable to system level testing and to monitoring failure characteristics in orbit.

Fast principal component analysis for stacking seismic data

NASA Astrophysics Data System (ADS)

Wu, Juan; Bai, Min

2018-04-01

Stacking seismic data plays an indispensable role in many steps of the seismic data processing and imaging workflow. Optimal stacking of seismic data can help mitigate seismic noise and enhance the principal components to a great extent. Traditional average-based seismic stacking methods cannot obtain optimal performance when the ambient noise is extremely strong. We propose a principal component analysis (PCA) algorithm for stacking seismic data without being sensitive to noise level. Considering the computational bottleneck of the classic PCA algorithm in processing massive seismic data, we propose an efficient PCA algorithm to make the proposed method readily applicable for industrial applications. Two numerically designed examples and one real seismic data are used to demonstrate the performance of the presented method.

Inactivation of DNA-Binding Response Regulator Sak189 Abrogates β-Antigen Expression and Affects Virulence of Streptococcus agalactiae

PubMed Central

Rozhdestvenskaya, Anastasia S.; Totolian, Artem A.; Dmitriev, Alexander V.

2010-01-01

Background Streptococcus agalactiae is able to colonize numerous tissues employing different mechanisms of gene regulation, particularly via two-component regulatory systems. These systems sense the environmental stimuli and regulate expression of the genes including virulence genes. Recently, the novel two-component regulatory system Sak188/Sak189 was identified. In S. agalactiae genome, it was adjacent to the bac gene encoding for β-antigen, an important virulence factor. Methodology/Principal Findings In this study, the sak188 and sak189 genes were inactivated, and the functional role of Sak188/Sak189 two-component system in regulation of the β-antigen expression was investigated. It was demonstrated that both transcription of bac gene and expression of encoded β-antigen were controlled by Sak189 response regulator, but not Sak188 histidine kinase. It was also found that the regulation occurred at transcriptional level. Finally, insertional inactivation of sak189 gene, but not sak188 gene, significantly affected virulent properties of S. agalactiae. Conclusions/Significance Sak189 response regulator is necessary for activation of bac gene transcription. It also controls the virulent properties of S. agalactiae. Given that the primary functional role of Sak188/Sak189 two-component systems is a control of bac gene transcription, this system can be annotated as BgrR/S (bac gene regulatory system). PMID:20419089

Microemulsions for Colorectal Cancer Treatments. General Considerations and Formulation of Methotrexate.

PubMed

Flores, Sergio E; Rial-Hermida, M Isabel; Ramirez, Jorge C; Pazos, Alejandro; Concheiro, Angel; Alvarez-Lorenzo, Carmen; Peralta, René D

2016-01-01

Microemulsions combine the advantages of emulsions with those of nanocarriers, overcoming the stability problems of the former and providing facile scalable systems with compartments adequate for high drug loadings. Recently, microemulsions are gaining attention in the formulation of anticancer drugs not only for topical treatment, but also for systemic delivery as well as for the development of theranostic systems. The aim of this paper is two-fold. First, an updated review about general features, preparation, characterization and pharmaceutical applications, with a special focus on colorectal cancer, is provided. Second, a case study of formulation of methotrexate in microemulsions is presented. Various essential oils (menthol, trans-anethole, α-tocopherol) and surfactants (TPGS-1000, Maxemul 6112, Noigen RN-20) were investigated for the preparation of o/w microemulsions for the delivery of methotrexate, and the ability of methotrexate-loaded microemulsions to inhibit cancer cell growth was then evaluated. Disregarding the surfactants used, menthol and trans-anethole led to cytotoxic microemulsions, whereas α-tocopherol based-formulations induced cell proliferation. These findings highlight the role that the oily component may play in the efficacy and safety of the microemulsions.

Detection of retromer assembly in Plasmodium falciparum by immunosensing coupled to Surface Plasmon Resonance.

PubMed

Iqbal, Mohd Shameel; Siddiqui, Asim Azhar; Banerjee, Chinmoy; Nag, Shiladitya; Mazumder, Somnath; De, Rudranil; Saha, Shubhra Jyoti; Karri, Suresh Kumar; Bandyopadhyay, Uday

Retromer complex plays a crucial role in intracellular protein trafficking and is conserved throughout the eukaryotes including malaria parasite, Plasmodium falciparum, where it is partially conserved. The assembly of retromer complex in RBC stages of malarial parasite is extremely difficult to explore because of its complicated physiology, small size, and intra-erythrocytic location. Nonetheless, understanding of retromer assembly may pave new ways for the development of novel antimalarials targeting parasite-specific protein trafficking pathways. Here, we investigated the assembly of retromer complex in P. falciparum, by an immunosensing method through highly sensitive Surface Plasmon Resonance (SPR) technique. After taking leads from the bioinformatics search and literature, different interacting proteins were identified and specific antibodies were raised against them. The sensor chip was prepared by covalently linking antibody specific to one component and the whole cell lysate was passed through it in order to trap the interacting complex. Antibodies raised against other interacting components were used to detect them in the trapped complex on the SPR chip. We were able to detect three different components in the retromer complex trapped by the immobilized antibody specific against a different component on a sensor chip. The assay was reproduced and validated in a different two-component CD74-MIF system in mammalian cells. We, thus, illustrate the assembly of retromer complex in P. falciparum through a bio-sensing approach that combines SPR with immunosensing requiring a very small amount of sample from the native source. Copyright © 2018 Elsevier B.V. All rights reserved.

The Community Climate System Model Version 4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gent, Peter R.; Danabasoglu, Gokhan; Donner, Leo J.

The fourth version of the Community Climate System Model (CCSM4) was recently completed and released to the climate community. This paper describes developments to all the CCSM components, and documents fully coupled pre-industrial control runs compared to the previous version, CCSM3. Using the standard atmosphere and land resolution of 1{sup o} results in the sea surface temperature biases in the major upwelling regions being comparable to the 1.4{sup o} resolution CCSM3. Two changes to the deep convection scheme in the atmosphere component result in the CCSM4 producing El Nino/Southern Oscillation variability with a much more realistic frequency distribution than themore » CCSM3, although the amplitude is too large compared to observations. They also improve the representation of the Madden-Julian Oscillation, and the frequency distribution of tropical precipitation. A new overflow parameterization in the ocean component leads to an improved simulation of the deep ocean density structure, especially in the North Atlantic. Changes to the CCSM4 land component lead to a much improved annual cycle of water storage, especially in the tropics. The CCSM4 sea ice component uses much more realistic albedos than the CCSM3, and the Arctic sea ice concentration is improved in the CCSM4. An ensemble of 20th century simulations runs produce an excellent match to the observed September Arctic sea ice extent from 1979 to 2005. The CCSM4 ensemble mean increase in globally-averaged surface temperature between 1850 and 2005 is larger than the observed increase by about 0.4 C. This is consistent with the fact that the CCSM4 does not include a representation of the indirect effects of aerosols, although other factors may come into play. The CCSM4 still has significant biases, such as the mean precipitation distribution in the tropical Pacific Ocean, too much low cloud in the Arctic, and the latitudinal distributions of short-wave and long-wave cloud forcings.« less

Genome plasticity and systems evolution in Streptomyces

PubMed Central

2012-01-01

Background Streptomycetes are filamentous soil-dwelling bacteria. They are best known as the producers of a great variety of natural products such as antibiotics, antifungals, antiparasitics, and anticancer agents and the decomposers of organic substances for carbon recycling. They are also model organisms for the studies of gene regulatory networks, morphological differentiation, and stress response. The availability of sets of genomes from closely related Streptomyces strains makes it possible to assess the mechanisms underlying genome plasticity and systems adaptation. Results We present the results of a comprehensive analysis of the genomes of five Streptomyces species with distinct phenotypes. These streptomycetes have a pan-genome comprised of 17,362 orthologous families which includes 3,096 components in the core genome, 5,066 components in the dispensable genome, and 9,200 components that are uniquely present in only one species. The core genome makes up about 33%-45% of each genome repertoire. It contains important genes for Streptomyces biology including those involved in gene regulation, secretion, secondary metabolism and morphological differentiation. Abundant duplicate genes have been identified, with 4%-11% of the whole genomes composed of lineage-specific expansions (LSEs), suggesting that frequent gene duplication or lateral gene transfer events play a role in shaping the genome diversification within this genus. Two patterns of expansion, single gene expansion and chromosome block expansion are observed, representing different scales of duplication. Conclusions Our results provide a catalog of genome components and their potential functional roles in gene regulatory networks and metabolic networks. The core genome components reveal the minimum requirement for streptomycetes to sustain a successful lifecycle in the soil environment, reflecting the effects of both genome evolution and environmental stress acting upon the expressed phenotypes. A better understanding of the LSE gene families will, on the other hand, bring a wealth of new insights into the mechanisms underlying strain-specific phenotypes, such as the production of novel antibiotics, pathogenesis, and adaptive response to environmental challenges. PMID:22759432

Comparison of O-Antigen gene clusters of all O-Serogroups of Escherichia coli and proposal for adopting a new nomenclature for O-Typing

USDA-ARS?s Scientific Manuscript database

Escherichia coli strains are classified based on O-antigens that are components of the lipopolysaccharide (LPS) in the cell envelope. O-antigens are important virulence factors, targets of both the innate and adaptive immune system, and play a role in host-pathogen interaction. Because they are hi...

Identification of Genes Controlled by the Essential YycFG Two-Component System Reveals a Role for Biofilm Modulation in Staphylococcus epidermidis.

PubMed

Xu, Tao; Wu, Yang; Lin, Zhiwei; Bertram, Ralph; Götz, Friedrich; Zhang, Ying; Qu, Di

2017-01-01

Biofilms play a crucial role in the pathogenicity of Staphylococcus epidermidis , while little is known about whether the essential YycFG two-component signal transduction system (TCS) is involved in biofilm formation. We used antisense RNA (asRNA) to silence the yycFG TCS in order to study its regulatory functions in S. epidermidis . Strain 1457 expressing asRNA yycF exhibited a significant delay (~4-5 h) in entry to log phase, which was partially complemented by overexpressing ssaA . The expression of asRNA yycF and asRNA yycG resulted in a 68 and 50% decrease in biofilm formation at 6 h, respectively, while they had no significant inhibitory effect on 12 h biofilm formation. The expression of asRNA yycF led to a ~5-fold increase in polysaccharide intercellular adhesion (PIA) production, but it did not affect the expression of accumulation-associated protein (Aap) or the release of extracellular DNA. Consistently, quantitative real-time PCR showed that silencing yycF resulted in an increased transcription of biofilm-related genes, including icaA, arlR, sarA, sarX , and sbp . An in silico search of the YycF regulon for the conserved YycF recognition pattern and a modified motif in S. epidermidis , along with additional gel shift and DNase I footprinting assays, showed that arlR, sarA, sarX , and icaA are directly regulated by YycF. Our data suggests that YycFG modulates S. epidermidis biofilm formation in an ica-dependent manner.

Identification of Genes Controlled by the Essential YycFG Two-Component System Reveals a Role for Biofilm Modulation in Staphylococcus epidermidis

PubMed Central

Xu, Tao; Wu, Yang; Lin, Zhiwei; Bertram, Ralph; Götz, Friedrich; Zhang, Ying; Qu, Di

2017-01-01

Biofilms play a crucial role in the pathogenicity of Staphylococcus epidermidis, while little is known about whether the essential YycFG two-component signal transduction system (TCS) is involved in biofilm formation. We used antisense RNA (asRNA) to silence the yycFG TCS in order to study its regulatory functions in S. epidermidis. Strain 1457 expressing asRNAyycF exhibited a significant delay (~4–5 h) in entry to log phase, which was partially complemented by overexpressing ssaA. The expression of asRNAyycF and asRNAyycG resulted in a 68 and 50% decrease in biofilm formation at 6 h, respectively, while they had no significant inhibitory effect on 12 h biofilm formation. The expression of asRNAyycF led to a ~5-fold increase in polysaccharide intercellular adhesion (PIA) production, but it did not affect the expression of accumulation-associated protein (Aap) or the release of extracellular DNA. Consistently, quantitative real-time PCR showed that silencing yycF resulted in an increased transcription of biofilm-related genes, including icaA, arlR, sarA, sarX, and sbp. An in silico search of the YycF regulon for the conserved YycF recognition pattern and a modified motif in S. epidermidis, along with additional gel shift and DNase I footprinting assays, showed that arlR, sarA, sarX, and icaA are directly regulated by YycF. Our data suggests that YycFG modulates S. epidermidis biofilm formation in an ica-dependent manner. PMID:28491057

Molecular and genetic characterization of the rhizopine catabolism (mocABRC) genes of Rhizobium meliloti L5-30.

PubMed

Rossbach, S; Kulpa, D A; Rossbach, U; de Bruijn, F J

1994-10-17

Rhizopine (L-3-O-methyl-scyllo-inosamine, 3-O-MSI) is a symbiosis-specific compound, which is synthesized in nitrogen-fixing nodules of Medicago sativa induced by Rhizobium meliloti strain L5-30. 3-O-MSI is thought to function as an unusual growth substrate for R. meliloti L5-30, which carries a locus (mos) responsible for its synthesis closely linked to a locus (moc) responsible for its degradation. Here, the essential moc genes were delimited by Tn5 mutagenesis and shown to be organized into two regions, separated by 3 kb of DNA. The DNA sequence of a 9-kb fragment spanning the two moc regions was determined, and four genes were identified that play an essential role in rhizopine catabolism (mocABC and mocR). The analysis of the DNA sequence and the amino acid sequence of the deduced protein products revealed that MocA resembles NADH-dependent dehydrogenases. MocB exhibits characteristic features of periplasmic-binding proteins that are components of high-affinity transport systems. MocC does not share significant homology with any protein in the database. MocR shows homology with the GntR class of bacterial regulator proteins. These results suggest that the mocABC genes are involved in the uptake and subsequent degradation of rhizopine, whereas mocR is likely to play a regulatory role.

The putative hydrolase YycJ (WalJ) affects the coordination of cell division with DNA replication in Bacillus subtilis and may play a conserved role in cell wall metabolism.

PubMed

Biller, Steven J; Wayne, Kyle J; Winkler, Malcolm E; Burkholder, William F

2011-02-01

Bacteria must accurately replicate and segregate their genetic information to ensure the production of viable daughter cells. The high fidelity of chromosome partitioning is achieved through mechanisms that coordinate cell division with DNA replication. We report that YycJ (WalJ), a predicted member of the metallo-β-lactamase superfamily found in most low-G+C Gram-positive bacteria, contributes to the fidelity of cell division in Bacillus subtilis. B. subtilis ΔwalJ (ΔwalJ(Bsu)) mutants divide over unsegregated chromosomes more frequently than wild-type cells, and this phenotype is exacerbated when DNA replication is inhibited. Two lines of evidence suggest that WalJ(Bsu) and its ortholog in the Gram-positive pathogen Streptococcus pneumoniae, WalJ(Spn) (VicX), play a role in cell wall metabolism: (i) strains of B. subtilis and S. pneumoniae lacking walJ exhibit increased sensitivity to a narrow spectrum of cephalosporin antibiotics, and (ii) reducing the expression of a two-component system that regulates genes involved in cell wall metabolism, WalRK (YycFG), renders walJ essential for growth in B. subtilis, as observed previously with S. pneumoniae. Together, these results suggest that the enzymatic activity of WalJ directly or indirectly affects cell wall metabolism and is required for accurate coordination of cell division with DNA replication.

A Novel Aerobic Degradation Pathway for Thiobencarb Is Initiated by the TmoAB Two-Component Flavin Mononucleotide-Dependent Monooxygenase System in Acidovorax sp. Strain T1

PubMed Central

Chu, Cui-Wei; Liu, Bin; Li, Na; Yao, Shi-Gang; Cheng, Dan; Zhao, Jia-Dong; Qiu, Ji-Guo; Yan, Xin; He, Jian

2017-01-01

ABSTRACT Thiobencarb is a thiocarbamate herbicide used in rice paddies worldwide. Microbial degradation plays a crucial role in the dissipation of thiobencarb in the environment. However, the physiological and genetic mechanisms underlying thiobencarb degradation remain unknown. In this study, a novel thiobencarb degradation pathway was proposed in Acidovorax sp. strain T1. Thiobencarb was oxidized and cleaved at the C—S bond, generating diethylcarbamothioic S-acid and 4-chlorobenzaldehyde (4CDA). 4CDA was then oxidized to 4-chlorobenzoic acid (4CBA) and hydrolytically dechlorinated to 4-hydroxybenzoic acid (4HBA). The identification of catabolic genes suggested further hydroxylation to protocatechuic acid (PCA) and finally degradation through the protocatechuate 4,5-dioxygenase pathway. A novel two-component monooxygenase system identified in the strain, TmoAB, was responsible for the initial catabolic reaction. TmoA shared 28 to 32% identity with the oxygenase components of pyrimidine monooxygenase from Agrobacterium fabrum, alkanesulfonate monooxygenase from Pseudomonas savastanoi, and dibenzothiophene monooxygenase from Rhodococcus sp. TmoB shared 25 to 37% identity with reported flavin reductases and oxidized NADH but not NADPH. TmoAB is a flavin mononucleotide (FMN)-dependent monooxygenase and catalyzed the C—S bond cleavage of thiobencarb. Introduction of tmoAB into cells of the thiobencarb degradation-deficient mutant T1m restored its ability to degrade and utilize thiobencarb. A dehydrogenase gene, tmoC, was located 7,129 bp downstream of tmoAB, and its transcription was clearly induced by thiobencarb. The purified TmoC catalyzed the dehydrogenation of 4CDA to 4CBA using NAD+ as a cofactor. A gene cluster responsible for the complete 4CBA metabolic pathway was also cloned, and its involvement in thiobencarb degradation was preliminarily verified by transcriptional analysis. IMPORTANCE Microbial degradation is the main factor in thiobencarb dissipation in soil. In previous studies, thiobencarb was degraded initially via N-deethylation, sulfoxidation, hydroxylation, and dechlorination. However, enzymes and genes involved in the microbial degradation of thiobencarb have not been studied. This study revealed a new thiobencarb degradation pathway in Acidovorax sp. strain T1 and identified a novel two-component FMN-dependent monooxygenase system, TmoAB. Under TmoAB-mediated catalysis, thiobencarb was cleaved at the C—S bond, producing diethylcarbamothioic S-acid and 4CDA. Furthermore, the downstream degradation pathway of thiobencarb was proposed. Our study provides the physiological, biochemical, and genetic foundation of thiobencarb degradation in this microorganism. PMID:28939603

A Novel Aerobic Degradation Pathway for Thiobencarb Is Initiated by the TmoAB Two-Component Flavin Mononucleotide-Dependent Monooxygenase System in Acidovorax sp. Strain T1.

PubMed

Chu, Cui-Wei; Liu, Bin; Li, Na; Yao, Shi-Gang; Cheng, Dan; Zhao, Jia-Dong; Qiu, Ji-Guo; Yan, Xin; He, Qin; He, Jian

2017-12-01

Thiobencarb is a thiocarbamate herbicide used in rice paddies worldwide. Microbial degradation plays a crucial role in the dissipation of thiobencarb in the environment. However, the physiological and genetic mechanisms underlying thiobencarb degradation remain unknown. In this study, a novel thiobencarb degradation pathway was proposed in Acidovorax sp. strain T1. Thiobencarb was oxidized and cleaved at the C-S bond, generating diethylcarbamothioic S -acid and 4-chlorobenzaldehyde (4CDA). 4CDA was then oxidized to 4-chlorobenzoic acid (4CBA) and hydrolytically dechlorinated to 4-hydroxybenzoic acid (4HBA). The identification of catabolic genes suggested further hydroxylation to protocatechuic acid (PCA) and finally degradation through the protocatechuate 4,5-dioxygenase pathway. A novel two-component monooxygenase system identified in the strain, TmoAB, was responsible for the initial catabolic reaction. TmoA shared 28 to 32% identity with the oxygenase components of pyrimidine monooxygenase from Agrobacterium fabrum , alkanesulfonate monooxygenase from Pseudomonas savastanoi , and dibenzothiophene monooxygenase from Rhodococcus sp. TmoB shared 25 to 37% identity with reported flavin reductases and oxidized NADH but not NADPH. TmoAB is a flavin mononucleotide (FMN)-dependent monooxygenase and catalyzed the C-S bond cleavage of thiobencarb. Introduction of tmoAB into cells of the thiobencarb degradation-deficient mutant T1m restored its ability to degrade and utilize thiobencarb. A dehydrogenase gene, tmoC , was located 7,129 bp downstream of tmoAB , and its transcription was clearly induced by thiobencarb. The purified TmoC catalyzed the dehydrogenation of 4CDA to 4CBA using NAD + as a cofactor. A gene cluster responsible for the complete 4CBA metabolic pathway was also cloned, and its involvement in thiobencarb degradation was preliminarily verified by transcriptional analysis. IMPORTANCE Microbial degradation is the main factor in thiobencarb dissipation in soil. In previous studies, thiobencarb was degraded initially via N -deethylation, sulfoxidation, hydroxylation, and dechlorination. However, enzymes and genes involved in the microbial degradation of thiobencarb have not been studied. This study revealed a new thiobencarb degradation pathway in Acidovorax sp. strain T1 and identified a novel two-component FMN-dependent monooxygenase system, TmoAB. Under TmoAB-mediated catalysis, thiobencarb was cleaved at the C-S bond, producing diethylcarbamothioic S -acid and 4CDA. Furthermore, the downstream degradation pathway of thiobencarb was proposed. Our study provides the physiological, biochemical, and genetic foundation of thiobencarb degradation in this microorganism. Copyright © 2017 American Society for Microbiology.

Multimode fiber optic wavelength division multiplexing

NASA Technical Reports Server (NTRS)

Spencer, J. L.

1982-01-01

Optical wavelength division multiplexing (WDM) systems, with signals transmitted on different wavelengths through a single optical fiber, can have increased bandwidth and fault isolation properties over single wavelength optical systems. Two WDM system designs that might be used with multimode fibers are considered and a general description of the components which could be used to implement the system are given. The components described are sources, multiplexers, demultiplexers, and detectors. Emphasis is given to the demultiplexer technique which is the major developmental component in the WDM system.

Absorption and fluorescence properties of colored dissolved organic matter in the Ross Sea during austral summer

NASA Astrophysics Data System (ADS)

D'Sa, E. J.; Kim, H. C.; Ha, S. Y.

2016-12-01

Colored dissolved organic matter (CDOM) spectral absorption and excitation-emission matrix (EEMs) fluorescence with parallel factor analysis (PARAFAC) were examined in the Ross Sea during a survey conducted on board the R/V Araon in the austral summer of 14/15. CDOM absorption at 355 nm ranged from 0.06 to 1.14 m-1 while spectral slope S calculated between 275-295 nm wavelength ranged from 18.83 to 33.32 µm-1 with water masses playing an important role in its variability. Spectral slope S decreased with increasing CDOM absorption indicating the strong role of photo-oxidation on CDOM abundance during the summer. PARAFAC analysis of EEM data identified two humic-like (terrestrial and marine-like) and a protein-like (tryptophan-like) component. The two humic-like components were well correlated with little variability spatially and across the water column ( 0-100 m) likely indicating more refractory material. The protein-like fluorescent component was relatively quite variable supporting the autochthonous production of this fluorescent component in the highly productive Ross Sea waters.

Enhanced Spectral Anisotropies Near the Proton-Cyclotron Scale: Possible Two-Component Structure in Hall-FLR MHD Turbulence Simulations

NASA Technical Reports Server (NTRS)

Ghosh, Sanjoy; Goldstein, Melvyn L.

2011-01-01

Recent analysis of the magnetic correlation function of solar wind fluctuations at 1 AU suggests the existence of two-component structure near the proton-cyclotron scale. Here we use two-and-one-half dimensional and three-dimensional compressible MHD models to look for two-component structure adjacent the proton-cyclotron scale. Our MHD system incorporates both Hall and Finite Larmor Radius (FLR) terms. We find that strong spectral anisotropies appear adjacent the proton-cyclotron scales depending on selections of initial condition and plasma beta. These anisotropies are enhancements on top of related anisotropies that appear in standard MHD turbulence in the presence of a mean magnetic field and are suggestive of one turbulence component along the inertial scales and another component adjacent the dissipative scales. We compute the relative strengths of linear and nonlinear accelerations on the velocity and magnetic fields to gauge the relative influence of terms that drive the system with wave-like (linear) versus turbulent (nonlinear) dynamics.

Shotgun proteomic analysis of Bombyx mori brain: emphasis on regulation of behavior and development of the nervous system.

PubMed

Wang, Guo-Bao; Zheng, Qin; Shen, Yun-Wang; Wu, Xiao-Feng

2016-02-01

The insect brain plays crucial roles in the regulation of growth and development and in all types of behavior. We used sodium dodecyl sulfate polyacrylamide gel electrophoresis and high-performance liquid chromatography - electron spray ionization tandem mass spectrometry (ESI-MS/MS) shotgun to identify the proteome of the silkworm brain, to investigate its protein composition and to understand their biological functions. A total of 2210 proteins with molecular weights in the range of 5.64-1539.82 kDa and isoelectric points in the range of 3.78-12.55 were identified. These proteins were annotated according to Gene Ontology Annotation into the categories of molecular function, biological process and cellular component. We characterized two categories of proteins: one includes behavior-related proteins involved in the regulation of behaviors, such as locomotion, reproduction and learning; the other consists of proteins related to the development or function of the nervous system. The identified proteins were classified into 283 different pathways according to KEGG analysis, including the PI3K-Akt signaling pathway which plays a crucial role in mediating survival signals in a wide range of neuronal cell types. This extensive protein profile provides a basis for further understanding of the physiological functions in the silkworm brain. © 2014 Institute of Zoology, Chinese Academy of Sciences.

An Investigation into Soft Error Detection Efficiency at Operating System Level

PubMed Central

Taheri, Hassan

2014-01-01

Electronic equipment operating in harsh environments such as space is subjected to a range of threats. The most important of these is radiation that gives rise to permanent and transient errors on microelectronic components. The occurrence rate of transient errors is significantly more than permanent errors. The transient errors, or soft errors, emerge in two formats: control flow errors (CFEs) and data errors. Valuable research results have already appeared in literature at hardware and software levels for their alleviation. However, there is the basic assumption behind these works that the operating system is reliable and the focus is on other system levels. In this paper, we investigate the effects of soft errors on the operating system components and compare their vulnerability with that of application level components. Results show that soft errors in operating system components affect both operating system and application level components. Therefore, by providing endurance to operating system level components against soft errors, both operating system and application level components gain tolerance. PMID:24574894

An investigation into soft error detection efficiency at operating system level.

PubMed

Asghari, Seyyed Amir; Kaynak, Okyay; Taheri, Hassan

2014-01-01

Electronic equipment operating in harsh environments such as space is subjected to a range of threats. The most important of these is radiation that gives rise to permanent and transient errors on microelectronic components. The occurrence rate of transient errors is significantly more than permanent errors. The transient errors, or soft errors, emerge in two formats: control flow errors (CFEs) and data errors. Valuable research results have already appeared in literature at hardware and software levels for their alleviation. However, there is the basic assumption behind these works that the operating system is reliable and the focus is on other system levels. In this paper, we investigate the effects of soft errors on the operating system components and compare their vulnerability with that of application level components. Results show that soft errors in operating system components affect both operating system and application level components. Therefore, by providing endurance to operating system level components against soft errors, both operating system and application level components gain tolerance.

Transformational Systems Concepts and Technologies for Our Future in Space

NASA Technical Reports Server (NTRS)

Howell, J. T.; George,P.; Mankins, J. C. (Editor); Christensen, C. B.

2004-01-01

NASA is constantly searching for new ideas and approaches yielding opportunities for assuring maximum returns on space infrastructure investments. Perhaps the idea of transformational innovation in developing space systems is long overdue. However, the concept of utilizing modular space system designs combined with stepping-stone development processes has merit and promises to return several times the original investment since each new space system or component is not treated as a unique and/or discrete design and development challenge. New space systems can be planned and designed so that each builds on the technology of previous systems and provides capabilities to support future advanced systems. Subsystems can be designed to use common modular components and achieve economies of scale, production, and operation. Standards, interoperability, and "plug and play" capabilities, when implemented vigorously and consistently, will result in systems that can be upgraded effectively with new technologies. This workshop explored many building-block approaches via way of example across a broad spectrum of technology discipline areas for potentially transforming space systems and inspiring future innovation. Details describing the workshop structure, process, and results are contained in this Conference Publication.

Stress Testing of Data-Communication Networks

NASA Technical Reports Server (NTRS)

Leucht, Kurt; Bedette, Guy

2006-01-01

NetStress is a computer program that stress-tests a data-communication network and components thereof. NetStress comprises two components running, respectively, in a transmitting system and a receiving system connected to a network under test

Role of the Renin-Angiotensin System, Renal Sympathetic Nerve System, and Oxidative Stress in Chronic Foot Shock-Induced Hypertension in Rats

PubMed Central

Dong, Tao; Chen, Jing-Wei; Tian, Li-Li; Wang, Lin-Hui; Jiang, Ren-Di; Zhang, Zhe; Xu, Jian-Bing; Zhao, Xiao-Dong; Zhu, Wei; Wang, Guo-Qing; Sun, Wan-Ping; Zhang, Guo-Xing

2015-01-01

Objective: The renin-angiotensin system (RAS) and renal sympathetic nerve system (RSNS) are involved in the development of hypertension. The present study is designed to explore the possible roles of the RAS and the RSNS in foot shock-induced hypertension. Methods: Male Sprague-Dawley rats were divided into six groups: control, foot shock, RSNS denervation, denervation plus foot shock, Captopril (angiotensin I converting enzyme inhibitor, ACE inhibitor) plus foot shock, and Tempol (superoxide dismutase mimetic) plus foot shock. Rats received foot shock for 14 days. We measured the quantity of thiobarbituric acid reactive substances (TBARS), corticosterone, renin, and angiotensin II (Ang II) in plasma, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and renal noradrenaline content. RAS component mRNA and protein levels were quantified in the cerebral cortex and hypothalamus. Results: The two week foot shock treatment significantly increased systolic blood pressure, which was accompanied by an increase in angiotensinogen, renin, ACE1, and AT1a mRNA and protein expression in the cerebral cortex and hypothalamus, an increase of the plasma concentrations of renin, Ang II, corticosterone, and TBARS, as well as a decrease in plasma SOD and GSH-Px activities. Systolic blood pressure increase was suppressed by denervation of the RSNS or treatment with Captopril or Tempol. Interestingly, denervation or Tempol treatment both decreased main RAS components not only in the circulatory system, but also in the central nervous system. In addition, decreased antioxidant levels and increased TBARS and corticosterone levels were also partially restored by denervation or treatment with Tempol or Captopril. Conclusions: RAS, RSNS and oxidative stress reciprocally potentiate to play important roles in the development of foot shock-induced hypertension. PMID:25999788

Role of the renin-angiotensin system, renal sympathetic nerve system, and oxidative stress in chronic foot shock-induced hypertension in rats.

PubMed

Dong, Tao; Chen, Jing-Wei; Tian, Li-Li; Wang, Lin-Hui; Jiang, Ren-Di; Zhang, Zhe; Xu, Jian-Bing; Zhao, Xiao-Dong; Zhu, Wei; Wang, Guo-Qing; Sun, Wan-Ping; Zhang, Guo-Xing

2015-01-01

The renin-angiotensin system (RAS) and renal sympathetic nerve system (RSNS) are involved in the development of hypertension. The present study is designed to explore the possible roles of the RAS and the RSNS in foot shock-induced hypertension. Male Sprague-Dawley rats were divided into six groups: control, foot shock, RSNS denervation, denervation plus foot shock, Captopril (angiotensin I converting enzyme inhibitor, ACE inhibitor) plus foot shock, and Tempol (superoxide dismutase mimetic) plus foot shock. Rats received foot shock for 14 days. We measured the quantity of thiobarbituric acid reactive substances (TBARS), corticosterone, renin, and angiotensin II (Ang II) in plasma, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and renal noradrenaline content. RAS component mRNA and protein levels were quantified in the cerebral cortex and hypothalamus. The two week foot shock treatment significantly increased systolic blood pressure, which was accompanied by an increase in angiotensinogen, renin, ACE1, and AT1a mRNA and protein expression in the cerebral cortex and hypothalamus, an increase of the plasma concentrations of renin, Ang II, corticosterone, and TBARS, as well as a decrease in plasma SOD and GSH-Px activities. Systolic blood pressure increase was suppressed by denervation of the RSNS or treatment with Captopril or Tempol. Interestingly, denervation or Tempol treatment both decreased main RAS components not only in the circulatory system, but also in the central nervous system. In addition, decreased antioxidant levels and increased TBARS and corticosterone levels were also partially restored by denervation or treatment with Tempol or Captopril. RAS, RSNS and oxidative stress reciprocally potentiate to play important roles in the development of foot shock-induced hypertension.

The effects of divergent and nondivergent winds on the kinetic energy budget of a mid-latitude cyclone - A case study

NASA Technical Reports Server (NTRS)

Chen, T.-C.; Alpert, J. C.; Schlatter, T. W.

1978-01-01

The magnitude of the divergent component of the wind is relatively small compared to that of the nondivergent component in large-scale atmospheric flows; nevertheless, it plays an important role in the case of explosive cyclogenesis examined here. The kinetic energy budget for the life cycle of an intense, developing cyclone over North America is calculated. The principal kinetic energy source is the net horizontal transport across the boundaries of the region enclosing the cyclone. By investigating the relative importance of the divergent and nondivergent wind components in the kinetic energy budget, it was found, as expected, that neglecting the divergent wind component in calculating the magnitude of the kinetic energy is of little consequence, but that the horizontal flux convergence and generation of kinetic energy depend crucially upon the divergent component. Modification of the divergent wind component can result in significant changes in the kinetic energy budget of the synoptic system.

Characterization and expression analysis of a complement component gene in sea cucumber ( Apostichopus japonicus)

NASA Astrophysics Data System (ADS)

Chen, Zhong; Zhou, Zunchun; Yang, Aifu; Dong, Ying; Guan, Xiaoyan; Jiang, Bei; Wang, Bai

2015-12-01

The complement system plays a crucial role in the innate immune system of animals. It can be activated by distinct yet overlapping classical, alternative and lectin pathways. In the alternative pathway, complement factor B (Bf) serves as the catalytic subunit of complement component 3 (C3) convertase, which plays the central role among three activation pathways. In this study, the Bf gene in sea cucumber ( Apostichopus japonicus), termed AjBf, was obtained by rapid amplification of cDNA ends (RACE). The full-length cDNA of AjBf was 3231 bp in length barring the poly (A) tail. It contained an open reading frame (ORF) of 2742 bp encoding 913 amino acids, a 105 bp 5'-UTR (5'-terminal untranslated region) and a 384 bp 3'-UTR. AjBf was a mosaic protein with six CCP (complement control protein) domains, a VWA (von Willebrand factor A) domain, and a serine protease domain. The deduced molecular weight of AjBf protein was 101 kDa. Quantitative real time PCR (qRT-PCR) analysis indicated that the expression level of AjBf in A. japonicus was obviously higher at larval stage than that at embryonic stage. Expression detection in different tissues showed that AjBf expressed higher in coelomocytes than in other four tissues. In addation, AjBf expression in different tissues was induced significantly after LPS or PolyI:C challenge. These results indicated that AjBf plays an important role in immune responses to pathogen infection.

Squeezing effects applied in nonclassical superposition states for quantum nanoelectronic circuits

NASA Astrophysics Data System (ADS)

Choi, Jeong Ryeol

2017-06-01

Quantum characteristics of a driven series RLC nanoelectronic circuit whose capacitance varies with time are studied using an invariant operator method together with a unitary transformation approach. In particular, squeezing effects and nonclassical properties of a superposition state composed of two displaced squeezed number states of equal amplitude, but 180° out of phase, are investigated in detail. We applied our developments to a solvable specific case obtained from a suitable choice of time-dependent parameters. The pattern of mechanical oscillation of the amount of charges stored in the capacitor, which are initially displaced, has exhibited more or less distortion due to the influence of the time-varying parameters of the system. We have analyzed squeezing effects of the system from diverse different angles and such effects are illustrated for better understanding. It has been confirmed that the degree of squeezing is not constant, but varies with time depending on specific situations. We have found that quantum interference occurs whenever the two components of the superposition meet together during the time evolution of the probability density. This outcome signifies the appearance of nonclassical features of the system. Nonclassicality of dynamical systems can be a potential resource necessary for realizing quantum information technique. Indeed, such nonclassical features of superposition states are expected to play a key role in upcoming information science which has attracted renewed attention recently.

Epidemics in interconnected small-world networks.

PubMed

Liu, Meng; Li, Daqing; Qin, Pengju; Liu, Chaoran; Wang, Huijuan; Wang, Feilong

2015-01-01

Networks can be used to describe the interconnections among individuals, which play an important role in the spread of disease. Although the small-world effect has been found to have a significant impact on epidemics in single networks, the small-world effect on epidemics in interconnected networks has rarely been considered. Here, we study the susceptible-infected-susceptible (SIS) model of epidemic spreading in a system comprising two interconnected small-world networks. We find that the epidemic threshold in such networks decreases when the rewiring probability of the component small-world networks increases. When the infection rate is low, the rewiring probability affects the global steady-state infection density, whereas when the infection rate is high, the infection density is insensitive to the rewiring probability. Moreover, epidemics in interconnected small-world networks are found to spread at different velocities that depend on the rewiring probability.

A review on interleukins: The key manipulators in rheumatoid arthritis.

PubMed

Sharma, Jatin; Bhar, Sutonuka; Devi, C Subathra

2017-09-01

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease associated with weakening of bones and joint pain. It primarily involves autoimmunity, matrix destruction, osteoclastogenesis, inflammation, and angiogenesis. Numerous cellular and humoral components of the immune system are involved in the etiology of diseases; however, the cardinal part is played by the inter-cellular signaling messengers called cytokines. Interleukins is a vaguely defined sub-class of cytokines that are abundantly found in the RA patients. The multifariousness and diversity in the function of the interleukins make them very likely to be associated with the pathogenesis in multiple ways. Nonetheless, the variety in opinions of researchers globally has led to contentious inferences. Ergo, in this review we have amalgamated the views of researchers from the past two decades till date to provide a comprehensive report about the role of interleukins in rheumatoid arthritis.

A comparative study on the histological structure of the spleen in the ostrich (Struthio camelus), the kestrel (Falco tinnunculus) and the osprey (Pandion haliaetus).

PubMed

Kozlu, Tolunay; Karadag Sari, Ebru; Akaydin Bozkurt, Yesim; Altunay, H

2011-06-01

The spleen structurally and functionally belongs to the hematopoietic organs and is also an important component of the reticuloendothelial system, which is known to play a major role in host defense. The histological structure of the spleen was investigated in the ostrich, a non-flying bird, the kestrel, a raptor, and the osprey, a fish-eating bird of prey (fish eagle). For this purpose, Mallory's modified triple stain, methyl green-pyronin and silver stain were used. Germinal centers were not present in the spleen of the osprey. In the spleen of the kestrel, penicillar arterioles and the surrounding lymphoid tissue were markedly dense. Compared to the other two birds, the red and white pulps were clearly distinguishable in the spleen of the ostrich.

Piano jacket for perceiving and playing music for patients with cerebral palsy.

PubMed

Lampe, Renée; Turova, Varvara; Alves-Pinto, Ana

2017-12-23

Patients with cerebral palsy with severe motor disabilities are limited not only in everyday life activities but also in choice of their hobbies. Playing a musical instrument is for the majority not possible, even though music constitutes a central component of many relaxation activities for people with disabilities. To give affected patients the opportunity to make music and to learn piano playing through somatosensory perception, a prototype of piano jacket was developed. A cycling jacket was equipped with boxes, each representing a musical note, incorporated into the sleeves. Each box contains vibration motors and LEDs. These can be used to translate the sequences of piano key presses performed at an external E-piano. An additional operation mode allows the user to actively play a melody himself by touching the same boxes that also incorporate touch sensor components. A working prototype of the piano jacket was developed. The sensory piano jacket provides patients with cerebral palsy and contractures the possibility to develop sensorimotor skills, motor abilities and participation in music-related activities. The jacket is planned to be used in music lessons. Implications for Rehabilitation The system is suitable even for patients with severe motor disabilities and especially joint contractures. Excellent handling through large easily accessible communication buttons. All building blocks are held in a garment, which allows for easy portability and gripping comfort.

Condition monitoring of distributed systems using two-stage Bayesian inference data fusion

NASA Astrophysics Data System (ADS)

Jaramillo, Víctor H.; Ottewill, James R.; Dudek, Rafał; Lepiarczyk, Dariusz; Pawlik, Paweł

2017-03-01

In industrial practice, condition monitoring is typically applied to critical machinery. A particular piece of machinery may have its own condition monitoring system that allows the health condition of said piece of equipment to be assessed independently of any connected assets. However, industrial machines are typically complex sets of components that continuously interact with one another. In some cases, dynamics resulting from the inception and development of a fault can propagate between individual components. For example, a fault in one component may lead to an increased vibration level in both the faulty component, as well as in connected healthy components. In such cases, a condition monitoring system focusing on a specific element in a connected set of components may either incorrectly indicate a fault, or conversely, a fault might be missed or masked due to the interaction of a piece of equipment with neighboring machines. In such cases, a more holistic condition monitoring approach that can not only account for such interactions, but utilize them to provide a more complete and definitive diagnostic picture of the health of the machinery is highly desirable. In this paper, a Two-Stage Bayesian Inference approach allowing data from separate condition monitoring systems to be combined is presented. Data from distributed condition monitoring systems are combined in two stages, the first data fusion occurring at a local, or component, level, and the second fusion combining data at a global level. Data obtained from an experimental rig consisting of an electric motor, two gearboxes, and a load, operating under a range of different fault conditions is used to illustrate the efficacy of the method at pinpointing the root cause of a problem. The obtained results suggest that the approach is adept at refining the diagnostic information obtained from each of the different machine components monitored, therefore improving the reliability of the health assessment of each individual element, as well as the entire piece of machinery.

Two-component duality and flavoring in the P+f model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dash, J.W.; Jones, S.T.; Martin, A.

We show that modern Regge fits to rising ..pi..N total cross sections sigma/sub piN/ using the Harari-Freund P+f model of diffraction are not consistent with two-component duality. If a conventional Pomeron is chosen (dominant j-plane pole plus weak cuts), the resulting f is ''dual'' to the resonances plus one-half the background. Conversely, constraining the f-pole amplitude by duality does not allow a reasonable fit to sigma/sub piN/. In contrast, the P-f identity model of diffraction is shown to satisfy a modified form of two-component duality. We show that by incorporating flavoring renormalization, the P+f picture can be made consistent withmore » duality. The unflavored P intercept is 0.91 and the flavored P intercept is 1.1. Significant absorptive j-plane cuts are also required, though these are small enough to be consistent with dominant short-range order. Thus flavoring, which is so essential in P-f identity phenomenology, seems to play a positive role in diffraction scattering generally.« less

Detection of histological anaplasia in gliomas with oligodendroglial components using positron emission tomography with (18)F-FDG and (11)C-methionine: report of two cases.

PubMed

Yamaguchi, Shigeru; Kobayashi, Hiroyuki; Hirata, Kenji; Shiga, Tohru; Tanaka, Shinya; Murata, Junichi; Terasaka, Shunsuke

2011-01-01

Gliomas are regionally heterogeneous tumors. Positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) and (11)C-methionine (MET) evaluates the heterogeneity of histological malignancy within the tumor. We present two patients with oligodendrocytic tumors that showed discrepancies in the highest uptake areas with these two tracers. PET studies with MET and FDG were performed on the same day, 2 weeks before surgery. In both cases, biopsy specimens were separately obtained from the highest MET and FDG uptake areas guided by intraoperative neuronavigation. Histological examinations demonstrated that the specimens from the highest MET uptake area revealed low-grade oligoastrocytoma or oligodendroglioma, whereas histological anaplasias were contained in the specimens from the highest FDG uptake area. With gliomas with oligodendroglial components, the MET uptake ratio does not always correspond to histological anaplasia, which can be detected only by FDG PET. Sole application of MET PET for preoperative evaluation may lead to misunderstanding of histological heterogeneity in gliomas, especially those with oligodendroglial components. FDG and MET tracers play complementary roles in preoperative evaluation of gliomas.

Divide and conquer: The Pseudomonas aeruginosa two-component hybrid SagS enables biofilm formation and recalcitrance of biofilm cells to antimicrobial agents via distinct regulatory circuits

PubMed Central

Petrova, Olga E.; Gupta, Kajal; Liao, Julie; Goodwine, James S.; Sauer, Karin

2017-01-01

The opportunistic pathogen Pseudomonas aeruginosa forms antimicrobial resistant biofilms through sequential steps requiring several two-component regulatory systems. The sensor-regulator hybrid SagS plays a central role in biofilm development by enabling the switch from the planktonic to the biofilm mode of growth, and by facilitating the transition of biofilm cells to a highly tolerant state. However, the mechanism by which SagS accomplishes both functions is unknown. SagS harbors a periplasmic sensory HmsP, and phosphorelay HisKA and Rec domains. We used SagS domain constructs and site-directed mutagenesis to elucidate how SagS performs its dual functions. We demonstrate that HisKA-Rec and the phospho-signaling between SagS and BfiS contribute to the switch to the biofilm mode of growth, but not to the tolerant state. Instead, expression of SagS domain constructs harboring HmsP rendered ΔsagS biofilm cells as recalcitrant to antimicrobial agents as wild-type biofilms, likely by restoring BrlR production and cellular c-di-GMP levels to wild-type levels. Restoration of biofilm tolerance by HmsP was independent of biofilm biomass accumulation, RsmA, RsmYZ, HptB, and BfiSR-downstream targets. Our findings thus suggest that SagS likely makes use of a “divide-and-conquer” mechanism to regulate its dual switch function, by activating two distinct regulatory networks via its individual domains. PMID:28263038

The critical role of the central nervous system (pro)renin receptor in regulating systemic blood pressure

PubMed Central

Xu, Quanbin; Jensen, Dane D.; Peng, Hua; Feng, Yumei

2016-01-01

The systemic renin–angiotensin system (RAS) has long been recognized as a critically important system in blood pressure (BP) regulation. However, extensive evidence has shown that a majority of RAS components are also present in many tissues and play indispensable roles in BP regulation. Here, we review evidence that RAS components, notably including the newly identified (pro)renin receptor (PRR), are present in the brain and are essential for the central regulation of BP. Binding of the PRR to its ligand, prorenin or renin, increases BP and promotes progression of cardiovascular diseases in an angiotensin II-dependent and -independent manner, establishing the PRR a promising antihypertensive drug target. We also review the existing PRR blockers, including handle region peptide and PRO20, and propose a rationale for blocking prorenin/PRR activation as a therapeutic approach that does not affect the actions of the PRR in vacuolar H+-ATPase and development. Finally, we summarize categories of currently available antihypertensive drugs and consider future perspectives. PMID:27113409

Template identification technology of nuclear warheads and components

NASA Astrophysics Data System (ADS)

Liu, Su-Ping; Gong, Jian; Hao, Fan-Hua; Hu, Guang-Chun

2008-02-01

Template identification technology (TIT) is designed for the scenarios where a batch of disarmed nuclear weapons or components would be dismantled to observe a nuclear disarmament treaty. The core function played by the TIT is to make a judgment on whether the verified item belongs to a certain kind of nuclear weapons or component (NW/NC) or to which kind the verified item belongs. This paper analyses the functions played by the TIT in the process of NW/NC dismantlement, and proposes that two phases would be followed when applying the TIT: firstly to establish NW/NC templates with a sample of size n drawn from a certain kind of disarmament NW; secondly to authenticate NW/NC by means of the TIT. This paper also expatiates some terms related to the concept of the TIT and investigates on the development status of NW/NC TIT based on radiation signatures. The study concludes that the design of template structure is crucial to the establishment of an effective TIT and that starting from different research angles and aiming at the same goal of classification different template structures and corresponding template identification methods can be built up to meet specific identification requirements.

Dissecting the regulon of the two-component system CvsSR: Identifying new virulence genes in Pseudomonas syringae pv. tomato DC3000

USDA-ARS?s Scientific Manuscript database

Recognition of environmental changes and regulation of genes that allow for adaption to those changes is essential for survival of bacteria. Two-component systems (TCSs) allow bacteria to sense and adapt to their environment. We previously identified the TCS CvsSR in the bacterial plant pathogen Pse...

The effects of an abolishing operation intervention component on play skills, challenging behavior, and stereotypy.

PubMed

Lang, Russell; O'Reilly, Mark; Sigafoos, Jeff; Machalicek, Wendy; Rispoli, Mandy; Lancioni, Giulio E; Aguilar, Jeannie; Fragale, Christina

2010-07-01

The purpose of this study was to reduce stereotypy and challenging behavior during play skills instruction by adding an abolishing operation component (AOC) to the intervention strategy. An alternating treatments design compared one condition in which participants were allowed to engage in stereotypy freely before beginning the play skills intervention (AOC condition) to a second condition without this free access period (No AOC condition). Across 4 participants with autism spectrum disorders (ASD), levels of stereotypy and challenging behavior were lower and functional play was higher during play intervention sessions that followed the AOC. These data provided support for the inclusion of an AOC in interventions aimed at increasing the play skills of children with ASD who present with stereotypy.

The multivariate egg: quantifying within- and among-clutch correlations between maternally derived yolk immunoglobulins and yolk androgens using multivariate mixed models.

PubMed

Postma, Erik; Siitari, Heli; Schwabl, Hubert; Richner, Heinz; Tschirren, Barbara

2014-03-01

Egg components are important mediators of prenatal maternal effects in birds and other oviparous species. Because different egg components can have opposite effects on offspring phenotype, selection is expected to favour their mutual adjustment, resulting in a significant covariation between egg components within and/or among clutches. Here we tested for such correlations between maternally derived yolk immunoglobulins and yolk androgens in great tit (Parus major) eggs using a multivariate mixed-model approach. We found no association between yolk immunoglobulins and yolk androgens within clutches, indicating that within clutches the two egg components are deposited independently. Across clutches, however, there was a significant negative relationship between yolk immunoglobulins and yolk androgens, suggesting that selection has co-adjusted their deposition. Furthermore, an experimental manipulation of ectoparasite load affected patterns of covariance among egg components. Yolk immunoglobulins are known to play an important role in nestling immune defence shortly after hatching, whereas yolk androgens, although having growth-enhancing effects under many environmental conditions, can be immunosuppressive. We therefore speculate that variation in the risk of parasitism may play an important role in shaping optimal egg composition and may lead to the observed pattern of yolk immunoglobulin and yolk androgen deposition across clutches. More generally, our case study exemplifies how multivariate mixed-model methodology presents a flexible tool to not only quantify, but also test patterns of (co)variation across different organisational levels and environments, allowing for powerful hypothesis testing in ecophysiology.

Aquarius' Object-Oriented, Plug and Play Component-Based Flight Software

NASA Technical Reports Server (NTRS)

Murray, Alexander; Shahabuddin, Mohammad

2013-01-01

The Aquarius mission involves a combined radiometer and radar instrument in low-Earth orbit, providing monthly global maps of Sea Surface Salinity. Operating successfully in orbit since June, 2011, the spacecraft bus was furnished by the Argentine space agency, Comision Nacional de Actividades Espaciales (CONAE). The instrument, built jointly by NASA's Caltech/JPL and Goddard Space Flight Center, has been successfully producing expectation-exceeding data since it was powered on in August of 2011. In addition to the radiometer and scatterometer, the instrument contains an command & data-handling subsystem with a computer and flight software (FSW) that is responsible for managing the instrument, its operation, and its data. Aquarius' FSW is conceived and architected as a Component-based system, in which the running software consists of a set of Components, each playing a distinctive role in the subsystem, instantiated and connected together at runtime. Component architectures feature a well-defined set of interfaces between the Components, visible and analyzable at the architectural level (see [1]). As we will describe, this kind of an architecture offers significant advantages over more traditional FSW architectures, which often feature a monolithic runtime structure. Component-based software is enabled by Object-Oriented (OO) techniques and languages, the use of which again is not typical in space mission FSW. We will argue in this paper that the use of OO design methods and tools (especially the Unified Modeling Language), as well as the judicious usage of C++, are very well suited to FSW applications, and we will present Aquarius FSW, describing our methods, processes, and design, as a successful case in point.

Separation of musical instruments based on amplitude and frequency comodulation

NASA Astrophysics Data System (ADS)

Jacobson, Barry D.; Cauwenberghs, Gert; Quatieri, Thomas F.

2002-05-01

In previous work, amplitude comodulation was investigated as a basis for monaural source separation. Amplitude comodulation refers to similarities in amplitude envelopes of individual spectral components emitted by particular types of sources. In many types of musical instruments, amplitudes of all resonant modes rise/fall, and start/stop together during the course of normal playing. We found that under certain well-defined conditions, a mixture of constant frequency, amplitude comodulated sources can unambiguously be decomposed into its constituents on the basis of these similarities. In this work, system performance was improved by relaxing the constant frequency requirement. String instruments, for example, which are normally played with vibrato, are both amplitude and frequency comodulated sources, and could not be properly tracked under the constant frequency assumption upon which our original algorithm was based. Frequency comodulation refers to similarities in frequency variations of individual harmonics emitted by these types of sources. The analytical difficulty is in defining a representation of the source which properly tracks frequency varying components. A simple, fixed filter bank can only track an individual spectral component for the duration in which it is within the passband of one of the filters. Alternatives are therefore explored which are amenable to real-time implementation.

Systematic mapping of two component response regulators to gene targets in a model sulfate reducing bacterium.

PubMed

Rajeev, Lara; Luning, Eric G; Dehal, Paramvir S; Price, Morgan N; Arkin, Adam P; Mukhopadhyay, Aindrila

2011-10-12

Two component regulatory systems are the primary form of signal transduction in bacteria. Although genomic binding sites have been determined for several eukaryotic and bacterial transcription factors, comprehensive identification of gene targets of two component response regulators remains challenging due to the lack of knowledge of the signals required for their activation. We focused our study on Desulfovibrio vulgaris Hildenborough, a sulfate reducing bacterium that encodes unusually diverse and largely uncharacterized two component signal transduction systems. We report the first systematic mapping of the genes regulated by all transcriptionally acting response regulators in a single bacterium. Our results enabled functional predictions for several response regulators and include key processes of carbon, nitrogen and energy metabolism, cell motility and biofilm formation, and responses to stresses such as nitrite, low potassium and phosphate starvation. Our study also led to the prediction of new genes and regulatory networks, which found corroboration in a compendium of transcriptome data available for D. vulgaris. For several regulators we predicted and experimentally verified the binding site motifs, most of which were discovered as part of this study. The gene targets identified for the response regulators allowed strong functional predictions to be made for the corresponding two component systems. By tracking the D. vulgaris regulators and their motifs outside the Desulfovibrio spp. we provide testable hypotheses regarding the functions of orthologous regulators in other organisms. The in vitro array based method optimized here is generally applicable for the study of such systems in all organisms.

Compact electrochemical sensor system and method for field testing for metals in saliva or other fluids

DOEpatents

Lin, Yuehe; Bennett, Wendy D.; Timchalk, Charles; Thrall, Karla D.

2004-03-02

Microanalytical systems based on a microfluidics/electrochemical detection scheme are described. Individual modules, such as microfabricated piezoelectrically actuated pumps and a microelectrochemical cell were integrated onto portable platforms. This allowed rapid change-out and repair of individual components by incorporating "plug and play" concepts now standard in PC's. Different integration schemes were used for construction of the microanalytical systems based on microfluidics/electrochemical detection. In one scheme, all individual modules were integrated in the surface of the standard microfluidic platform based on a plug-and-play design. Microelectrochemical flow cell which integrated three electrodes based on a wall-jet design was fabricated on polymer substrate. The microelectrochemical flow cell was then plugged directly into the microfluidic platform. Another integration scheme was based on a multilayer lamination method utilizing stacking modules with different functionality to achieve a compact microanalytical device. Application of the microanalytical system for detection of lead in, for example, river water and saliva samples using stripping voltammetry is described.

[New idea of traditional Chinese medicine quality control based on "composition structure" theory].

PubMed

Liu, Dan; Jia, Xiaobin; Yu, Danhong

2012-03-01

On the road of the modern Chinese medicine developing internationally, there is a key issues that setting up a reasonable, accurate and be quantified quality evaluation system which is comply with the basic theory of Chinese medicine. Based on the overall understanding of the role of traditional Chinese medicine components, author suggested that the idea of "structural components" theory should be embedded into the system and thought the Chinese medicine play a multi-target, multi-channel pharmacodynamic effects founded on the specific microcosmic structural relationship between the components and the components within the group. At present, the way of Chinese pharmacopoeia checking the quality of Chinese medicine is mainly depends on controlling the single or multiple targets of ingredients. In fact, this way is out of the overall effectiveness of the Chinese medicine, so we can not thoroughly controlling the quality of Chinese medicine from the essence of the Chinese medicine. Secondly, it's only macro-structural quantity that the Chinese pharmacopoeia just controlling the less effective ingredients, this is not enough to reflect the internal microstructure of the integrity and systematic. In other words, this cannot reflect the structural components of the Chinese medicine (the essence of traditional Chinese medicine). In view of above mentioned reasons, the author propose the new idea on the quality control in the medicine that quantify the ratio structural relationship in component and the ingredients of the components, set the optimal controlling proportion between the components and ingredients. At the same time, author thought we should conduct the depth study in the micro-quantified the multi-component and multi-ingredient, in the process of studying the material basis of Chinese medicine. Therefore, it could establish a more rational basis for the Chinese medicine quality controlling system.

ROCK inhibition abolishes the establishment of the aquiferous system in Ephydatia muelleri (Porifera, Demospongiae).

PubMed

Schenkelaars, Quentin; Quintero, Omar; Hall, Chelsea; Fierro-Constain, Laura; Renard, Emmanuelle; Borchiellini, Carole; Hill, April L

2016-04-15

The Rho associated coiled-coil protein kinase (ROCK) plays crucial roles in development across bilaterian animals. The fact that the Rho/Rock pathway is required to initiate epithelial morphogenesis and thus to establish body plans in bilaterians makes this conserved signaling pathway key for studying the molecular mechanisms that may control early development of basally branching metazoans. The purpose of this study was to evaluate whether or not the main components of this signaling pathway exist in sponges, and if present, to investigate the possible role of the regulatory network in an early branching non-bilaterian species by evaluating ROCK function during Ephydatia muelleri development. Molecular phylogenetic analyses and protein domain predictions revealed the existence of Rho/Rock components in all studied poriferan lineages. Binding assays revealed that both Y-27632 and GSK429286A are capable of inhibiting Em-ROCK activity in vitro. Treatment with both drugs leads to impairment of growth and formation of the basal pinacoderm layer in the developing sponge. Furthermore, inhibition of Em-Rock prevents the establishment of a functional aquiferous system, including the absence of an osculum. In contrast, no effect of ROCK inhibition was observed in juvenile sponges that already possess a fully developed and functional aquiferous system. Thus, the Rho/Rock pathway appears to be essential for the proper development of the freshwater sponge, and may play a role in various cell behaviors (e.g. cell proliferation, cell adhesion and cell motility). Taken together, these data are consistent with an ancestral function of Rho/Rock signaling in playing roles in early developmental processes and may provide a new framework to study the interaction between Wnt signaling and the Rho/Rock pathway. Copyright © 2016 Elsevier Inc. All rights reserved.

Low-Dimensional Models for Physiological Systems: Nonlinear Coupling of Gas and Liquid Flows

NASA Astrophysics Data System (ADS)

Staples, A. E.; Oran, E. S.; Boris, J. P.; Kailasanath, K.

2006-11-01

Current computational models of biological organisms focus on the details of a specific component of the organism. For example, very detailed models of the human heart, an aorta, a vein, or part of the respiratory or digestive system, are considered either independently from the rest of the body, or as interacting simply with other systems and components in the body. In actual biological organisms, these components and systems are strongly coupled and interact in complex, nonlinear ways leading to complicated global behavior. Here we describe a low-order computational model of two physiological systems, based loosely on a circulatory and respiratory system. Each system is represented as a one-dimensional fluid system with an interconnected series of mass sources, pumps, valves, and other network components, as appropriate, representing different physical organs and system components. Preliminary results from a first version of this model system are presented.

Reliability demonstration test for load-sharing systems with exponential and Weibull components

PubMed Central

Hu, Qingpei; Yu, Dan; Xie, Min

2017-01-01

Conducting a Reliability Demonstration Test (RDT) is a crucial step in production. Products are tested under certain schemes to demonstrate whether their reliability indices reach pre-specified thresholds. Test schemes for RDT have been studied in different situations, e.g., lifetime testing, degradation testing and accelerated testing. Systems designed with several structures are also investigated in many RDT plans. Despite the availability of a range of test plans for different systems, RDT planning for load-sharing systems hasn’t yet received the attention it deserves. In this paper, we propose a demonstration method for two specific types of load-sharing systems with components subject to two distributions: exponential and Weibull. Based on the assumptions and interpretations made in several previous works on such load-sharing systems, we set the mean time to failure (MTTF) of the total system as the demonstration target. We represent the MTTF as a summation of mean time between successive component failures. Next, we introduce generalized test statistics for both the underlying distributions. Finally, RDT plans for the two types of systems are established on the basis of these test statistics. PMID:29284030

Reliability demonstration test for load-sharing systems with exponential and Weibull components.

PubMed

Xu, Jianyu; Hu, Qingpei; Yu, Dan; Xie, Min

2017-01-01

Conducting a Reliability Demonstration Test (RDT) is a crucial step in production. Products are tested under certain schemes to demonstrate whether their reliability indices reach pre-specified thresholds. Test schemes for RDT have been studied in different situations, e.g., lifetime testing, degradation testing and accelerated testing. Systems designed with several structures are also investigated in many RDT plans. Despite the availability of a range of test plans for different systems, RDT planning for load-sharing systems hasn't yet received the attention it deserves. In this paper, we propose a demonstration method for two specific types of load-sharing systems with components subject to two distributions: exponential and Weibull. Based on the assumptions and interpretations made in several previous works on such load-sharing systems, we set the mean time to failure (MTTF) of the total system as the demonstration target. We represent the MTTF as a summation of mean time between successive component failures. Next, we introduce generalized test statistics for both the underlying distributions. Finally, RDT plans for the two types of systems are established on the basis of these test statistics.

Feasibility Study of a Generalized Framework for Developing Computer-Aided Detection Systems-a New Paradigm.

PubMed

Nemoto, Mitsutaka; Hayashi, Naoto; Hanaoka, Shouhei; Nomura, Yukihiro; Miki, Soichiro; Yoshikawa, Takeharu

2017-10-01

We propose a generalized framework for developing computer-aided detection (CADe) systems whose characteristics depend only on those of the training dataset. The purpose of this study is to show the feasibility of the framework. Two different CADe systems were experimentally developed by a prototype of the framework, but with different training datasets. The CADe systems include four components; preprocessing, candidate area extraction, candidate detection, and candidate classification. Four pretrained algorithms with dedicated optimization/setting methods corresponding to the respective components were prepared in advance. The pretrained algorithms were sequentially trained in the order of processing of the components. In this study, two different datasets, brain MRA with cerebral aneurysms and chest CT with lung nodules, were collected to develop two different types of CADe systems in the framework. The performances of the developed CADe systems were evaluated by threefold cross-validation. The CADe systems for detecting cerebral aneurysms in brain MRAs and for detecting lung nodules in chest CTs were successfully developed using the respective datasets. The framework was shown to be feasible by the successful development of the two different types of CADe systems. The feasibility of this framework shows promise for a new paradigm in the development of CADe systems: development of CADe systems without any lesion specific algorithm designing.

Identification of a two-component signal transduction system involved in fimbriation of Porphyromonas gingivalis.

PubMed

Hayashi, J; Nishikawa, K; Hirano, R; Noguchi, T; Yoshimura, F

2000-01-01

Porphyromonas gingivalis, a periodontopathogen, is an oral anaerobic gram-negative bacterium with numerous fimbriae on the cell surface. Fimbriae have been considered to be an important virulence factor in this organism. We analyzed the genomic DNA of transposon-induced, fimbria-deficient mutants derived from ATCC 33277 and found that seven independent mutants had transposon insertions within the same restriction fragment. Cloning and sequencing of the disrupted region from one of the mutants revealed two adjacent open reading frames (ORFs) which seemed to encode a two-component signal transduction system. We also found that six of the mutants had insertions in a gene, fimS, a homologue of the genes encoding sensor kinase, and that the insertion in the remaining one disrupted the gene immediately downstream, fimR, a homologue of the response regulator genes in other bacteria. These findings suggest that this two-component regulatory system is involved in fimbriation of P. gingivalis.

A complex network-based importance measure for mechatronics systems

NASA Astrophysics Data System (ADS)

Wang, Yanhui; Bi, Lifeng; Lin, Shuai; Li, Man; Shi, Hao

2017-01-01

In view of the negative impact of functional dependency, this paper attempts to provide an alternative importance measure called Improved-PageRank (IPR) for measuring the importance of components in mechatronics systems. IPR is a meaningful extension of the centrality measures in complex network, which considers usage reliability of components and functional dependency between components to increase importance measures usefulness. Our work makes two important contributions. First, this paper integrates the literature of mechatronic architecture and complex networks theory to define component network. Second, based on the notion of component network, a meaningful IPR is brought into the identifying of important components. In addition, the IPR component importance measures, and an algorithm to perform stochastic ordering of components due to the time-varying nature of usage reliability of components and functional dependency between components, are illustrated with a component network of bogie system that consists of 27 components.

Disordered hyperuniformity in two-component nonadditive hard-disk plasmas

NASA Astrophysics Data System (ADS)

Lomba, Enrique; Weis, Jean-Jacques; Torquato, Salvatore

2017-12-01

We study the behavior of a classical two-component ionic plasma made up of nonadditive hard disks with additional logarithmic Coulomb interactions between them. Due to the Coulomb repulsion, long-wavelength total density fluctuations are suppressed and the system is globally hyperuniform. Short-range volume effects lead to phase separation or to heterocoordination for positive or negative nonadditivities, respectively. These effects compete with the hidden long-range order imposed by hyperuniformity. As a result, the critical behavior of the mixture is modified, with long-wavelength concentration fluctuations partially damped when the system is charged. It is also shown that the decrease of configurational entropy due to hyperuniformity originates from contributions beyond the two-particle level. Finally, despite global hyperuniformity, we show that in our system the spatial configuration associated with each component separately is not hyperuniform, i.e., the system is not "multihyperuniform."

Personalized USB Biosensor Module for Effective ECG Monitoring.

PubMed

Sladojević, Srdjan; Arsenović, Marko; Lončar-Turukalo, Tatjana; Sladojević, Miroslava; Ćulibrk, Dubravko

2016-01-01

The burden of chronic disease and associated disability present a major threat to financial sustainability of healthcare delivery systems. The need for cost-effective early diagnosis and disease prevention is evident driving the development of personalized home health solutions. The proposed solution presents an easy to use ECG monitoring system. The core hardware component is a biosensor dongle with sensing probes at one end, and micro USB interface at the other end, offering reliable and unobtrusive sensing, preprocessing and storage. An additional component is a smart phone, providing both the biosensor's power supply and an intuitive user application for the real-time data reading. The system usage is simplified, with innovative solutions offering plug and play functionality avoiding additional driver installation. Personalized needs could be met with different sensor combinations enabling adequate monitoring in chronic disease, during physical activity and in the rehabilitation process.

Coarse-graining as a downward causation mechanism

NASA Astrophysics Data System (ADS)

Flack, Jessica C.

2017-11-01

Downward causation is the controversial idea that `higher' levels of organization can causally influence behaviour at `lower' levels of organization. Here I propose that we can gain traction on downward causation by being operational and examining how adaptive systems identify regularities in evolutionary or learning time and use these regularities to guide behaviour. I suggest that in many adaptive systems components collectively compute their macroscopic worlds through coarse-graining. I further suggest we move from simple feedback to downward causation when components tune behaviour in response to estimates of collectively computed macroscopic properties. I introduce a weak and strong notion of downward causation and discuss the role the strong form plays in the origins of new organizational levels. I illustrate these points with examples from the study of biological and social systems and deep neural networks. This article is part of the themed issue 'Reconceptualizing the origins of life'.

Coarse-graining as a downward causation mechanism

PubMed Central

2017-01-01

Downward causation is the controversial idea that ‘higher’ levels of organization can causally influence behaviour at ‘lower’ levels of organization. Here I propose that we can gain traction on downward causation by being operational and examining how adaptive systems identify regularities in evolutionary or learning time and use these regularities to guide behaviour. I suggest that in many adaptive systems components collectively compute their macroscopic worlds through coarse-graining. I further suggest we move from simple feedback to downward causation when components tune behaviour in response to estimates of collectively computed macroscopic properties. I introduce a weak and strong notion of downward causation and discuss the role the strong form plays in the origins of new organizational levels. I illustrate these points with examples from the study of biological and social systems and deep neural networks. This article is part of the themed issue ‘Reconceptualizing the origins of life’. PMID:29133440

Combined CT-based and image-free navigation systems in TKA reduces postoperative outliers of rotational alignment of the tibial component.

PubMed

Mitsuhashi, Shota; Akamatsu, Yasushi; Kobayashi, Hideo; Kusayama, Yoshihiro; Kumagai, Ken; Saito, Tomoyuki

2018-02-01

Rotational malpositioning of the tibial component can lead to poor functional outcome in TKA. Although various surgical techniques have been proposed, precise rotational placement of the tibial component was difficult to accomplish even with the use of a navigation system. The purpose of this study is to assess whether combined CT-based and image-free navigation systems replicate accurately the rotational alignment of tibial component that was preoperatively planned on CT, compared with the conventional method. We compared the number of outliers for rotational alignment of the tibial component using combined CT-based and image-free navigation systems (navigated group) with those of conventional method (conventional group). Seventy-two TKAs were performed between May 2012 and December 2014. In the navigated group, the anteroposterior axis was prepared using CT-based navigation system and the tibial component was positioned under control of the navigation. In the conventional group, the tibial component was placed with reference to the Akagi line that was determined visually. Fisher's exact probability test was performed to evaluate the results. There was a significant difference between the two groups with regard to the number of outliers: 3 outliers in the navigated group compared with 12 outliers in the conventional group (P < 0.01). We concluded that combined CT-based and image-free navigation systems decreased the number of rotational outliers of tibial component, and was helpful for the replication of the accurate rotational alignment of the tibial component that was preoperatively planned.

Development Of Autonomous Systems

NASA Astrophysics Data System (ADS)

Kanade, Takeo

1989-03-01

In the last several years at the Robotics Institute of Carnegie Mellon University, we have been working on two projects for developing autonomous systems: Nablab for Autonomous Land Vehicle and Ambler for Mars Rover. These two systems are for different purposes: the Navlab is a four-wheeled vehicle (van) for road and open terrain navigation, and the Ambler is a six-legged locomotor for Mars exploration. The two projects, however, share many common aspects. Both are large-scale integrated systems for navigation. In addition to the development of individual components (eg., construction and control of the vehicle, vision and perception, and planning), integration of those component technologies into a system by means of an appropriate architecture is a major issue.

Interfaces - Weak Links, Yet Great Opportunities

NASA Technical Reports Server (NTRS)

Hendricks, Robert C.; Dimofte, Florin; Chupp, Raymond E.; Steinetz, Bruce M.

2011-01-01

Inadequate turbomachine interface design can rapidly degrade system performance, yet provide great opportunity for improvements. Engineered coatings of seals and bearing interfaces are major issues in the operational life of power systems. Coatings, films, and combined use of both metals and ceramics play a major role in maintaining component life. Interface coatings, like lubricants, are sacrificial for the benefit of the component. Bearing and sealing surfaces are routinely protected by tribologically paired coatings such as silicon diamond like coatings (SiDLC) in combination with an oil lubricated wave bearing that prolongs bearing operational life. Likewise, of several methods used or researched for detecting interface failures, dopants within coatings show failures in functionally graded ceramic coatings. The Bozzolo-Ferrante-Smith (BFS) materials models and quantum mechanical tools, employed in interface design, are discussed.

40 CFR Appendix E to Part 63 - Monitoring Procedure for Nonthoroughly Mixed Open Biological Treatment Systems at Kraft Pulp...

Code of Federal Regulations, 2010 CFR

2010-07-01

... two separate components. The first data collection component demonstrates that the open biological... each zone of the open biological treatment unit. After the first two components of data collection are... determined using actual sampling data from the open biological treatment unit. This is done during the...

40 CFR Appendix E to Part 63 - Monitoring Procedure for Nonthoroughly Mixed Open Biological Treatment Systems at Kraft Pulp...

Code of Federal Regulations, 2011 CFR

2011-07-01

... two separate components. The first data collection component demonstrates that the open biological... each zone of the open biological treatment unit. After the first two components of data collection are... determined using actual sampling data from the open biological treatment unit. This is done during the...

Two-dimensional symbiotic solitons and vortices in binary condensates with attractive cross-species interaction

PubMed Central

Ma, Xuekai; Driben, Rodislav; Malomed, Boris A.; Meier, Torsten; Schumacher, Stefan

2016-01-01

We consider a two-dimensional (2D) two-component spinor system with cubic attraction between the components and intra-species self-repulsion, which may be realized in atomic Bose-Einstein condensates, as well as in a quasi-equilibrium condensate of microcavity polaritons. Including a 2D spatially periodic potential, which is necessary for the stabilization of the system against the critical collapse, we use detailed numerical calculations and an analytical variational approximation (VA) to predict the existence and stability of several types of 2D symbiotic solitons in the spinor system. Stability ranges are found for symmetric and asymmetric symbiotic fundamental solitons and vortices, including hidden-vorticity (HV) modes, with opposite vorticities in the two components. The VA produces exceptionally accurate predictions for the fundamental solitons and vortices. The fundamental solitons, both symmetric and asymmetric ones, are completely stable, in either case when they exist as gap solitons or regular ones. The symmetric and asymmetric vortices are stable if the inter-component attraction is stronger than the intra-species repulsion, while the HV modes have their stability region in the opposite case. PMID:27703235

A Second Quorum-Sensing System Regulates Cell Surface Properties but Not Phenazine Antibiotic Production in Pseudomonas aureofaciens

PubMed Central

Zhang, Zhongge; Pierson, Leland S.

2001-01-01

The root-associated biological control bacterium Pseudomonas aureofaciens 30-84 produces a range of exoproducts, including protease and phenazines. Phenazine antibiotic biosynthesis by phzXYFABCD is regulated in part by the PhzR-PhzI quorum-sensing system. Mutants defective in phzR or phzI produce very low levels of phenazines but wild-type levels of exoprotease. In the present study, a second genomic region of strain 30-84 was identified that, when present in trans, increased β-galactosidase activity in a genomic phzB::lacZ reporter and partially restored phenazine production to a phzR mutant. Sequence analysis identified two adjacent genes, csaR and csaI, that encode members of the LuxR-LuxI family of regulatory proteins. No putative promoter region is present upstream of the csaI start codon and no lux box-like element was found in either the csaR promoter or the 30-bp intergenic region between csaR and csaI. Both the PhzR-PhzI and CsaR-CsaI systems are regulated by the GacS-GacA two-component regulatory system. In contrast to the multicopy effects of csaR and csaI in trans, a genomic csaR mutant (30-84R2) and a csaI mutant (30-84I2) did not exhibit altered phenazine production in vitro or in situ, indicating that the CsaR-CsaI system is not involved in phenazine regulation in strain 30-84. Both mutants also produced wild-type levels of protease. However, disruption of both csaI and phzI or both csaR and phzR eliminated both phenazine and protease production completely. Thus, the two quorum-sensing systems do not interact for phenazine regulation but do interact for protease regulation. Additionally, the CsaI N-acylhomoserine lactone (AHL) signal was not recognized by the phenazine AHL reporter 30-84I/Z but was recognized by the AHL reporters Chromobacterium violaceum CV026 and Agrobacterium tumefaciens A136(pCF240). Inactivation of csaR resulted in a smooth mucoid colony phenotype and formation of cell aggregates in broth, suggesting that CsaR is involved in regulating biosynthesis of cell surface components. Strain 30-84I/I2 exhibited mucoid colony and clumping phenotypes similar to those of 30-84R2. Both phenotypes were reversed by complementation with csaR-csaI or by the addition of the CsaI AHL signal. Both quorum-sensing systems play a role in colonization by strain 30-84. Whereas loss of PhzR resulted in a 6.6-fold decrease in colonization by strain 30-84 on wheat roots in natural soil, a phzR csaR double mutant resulted in a 47-fold decrease. These data suggest that gene(s) regulated by the CsaR-CsaI system also plays a role in the rhizosphere competence of P. aureofaciens 30-84. PMID:11526037

Phylogenetic aspects of the complement system.

PubMed

Zarkadis, I K; Mastellos, D; Lambris, J D

2001-01-01

During evolution two general systems of immunity have emerged: innate or, natural immunity and adaptive (acquired), or specific immunity. The innate system is phylogenetically older and is found in some form in all multicellular organisms, whereas the adaptive system appeared about 450 million years ago and is found in all vertebrates except jawless fish. The complement system in higher vertebrates plays an important role as an effector of both the innate and the acquired immune response, and also participates in various immunoregulatory processes. In lower vertebrates complement is activated by the alternative and lectin pathways and is primarily involved in the opsonization of foreign material. The Agnatha (the most primitive vertebrate species) possess the alternative and lectin pathways while cartilaginous fish are the first species in which the classical pathway appears following the emergence of immunoglobulins. The rest of the poikilothermic species, ranging from teleosts to reptilians, appear to contain a well-developed complement system resembling that of the homeothermic vertebrates. It seems that most of the complement components have appeared after the duplication of primordial genes encoding C3/C4/C5, fB/C2, C1s/C1r/MASP-1/MASP-2, and C6/C7/C8/C9 molecules, in a process that led to the formation of distinct activation pathways. However, unlike homeotherms, several species of poikilotherms (e.g. trout) have recently been shown to possess multiple forms of complement components (C3, factor B) that are structurally and functionally more diverse than those of higher vertebrates. We hypothesize that this remarkable diversity has allowed these animals to expand their innate capacity for immune recognition and response. Recent studies have also indicated the possible presence of complement receptors in protochordates and lower vertebrates. In conclusion, there is considerable evidence suggesting that the complement system is present in the entire lineage of deuterostomes, and regulatory complement components have been identified in all species beyond the protochordates, indicating that the mechanisms of complement activation and regulation have developed in parallel.

Self-powered switch-controlled nucleic acid extraction system.

PubMed

Han, Kyungsup; Yoon, Yong-Jin; Shin, Yong; Park, Mi Kyoung

2016-01-07

Over the past few decades, lab-on-a-chip (LOC) technologies have played a great role in revolutionizing the way in vitro medical diagnostics are conducted and transforming bulky and expensive laboratory instruments and labour-intensive tests into easy to use, cost-effective miniaturized systems with faster analysis time, which can be used for near-patient or point-of-care (POC) tests. Fluidic pumps and valves are among the key components for LOC systems; however, they often require on-line electrical power or batteries and make the whole system bulky and complex, therefore limiting its application to POC testing especially in low-resource setting. This is particularly problematic for molecular diagnostics where multi-step sample processing (e.g. lysing, washing, elution) is necessary. In this work, we have developed a self-powered switch-controlled nucleic acid extraction system (SSNES). The main components of SSNES are a powerless vacuum actuator using two disposable syringes and a switchgear made of PMMA blocks and an O-ring. In the vacuum actuator, an opened syringe and a blocked syringe are bound together and act as a working syringe and an actuating syringe, respectively. The negative pressure in the opened syringe is generated by a restoring force of the compressed air inside the blocked syringe and utilized as the vacuum source. The Venus symbol shape of the switchgear provides multiple functions including being a reagent reservoir, a push-button for the vacuum actuator, and an on-off valve. The SSNES consists of three sets of vacuum actuators, switchgears and microfluidic components. The entire system can be easily fabricated and is fully disposable. We have successfully demonstrated DNA extraction from a urine sample using a dimethyl adipimidate (DMA)-based extraction method and the performance of the DNA extraction has been confirmed by genetic (HRAS) analysis of DNA biomarkers from the extracted DNAs using the SSNES. Therefore, the SSNES can be widely used as a powerless and disposable system for DNA extraction and the syringe-based vacuum actuator would be easily utilized for diverse applications with various microchannels as a powerless fluidic pump.

Systems biology approaches to understand the effects of nutrition and promote health.

PubMed

Badimon, Lina; Vilahur, Gemma; Padro, Teresa

2017-01-01

Within the last years the implementation of systems biology in nutritional research has emerged as a powerful tool to understand the mechanisms by which dietary components promote health and prevent disease as well as to identify the biologically active molecules involved in such effects. Systems biology, by combining several '-omics' disciplines (mainly genomics/transcriptomics, proteomics and metabolomics), creates large data sets that upon computational integration provide in silico predictive networks that allow a more extensive analysis of the individual response to a nutritional intervention and provide a more global comprehensive understanding of how diet may influence health and disease. Numerous studies have demonstrated that diet and particularly bioactive food components play a pivotal role in helping to counteract environmental-related oxidative damage. Oxidative stress is considered to be strongly implicated in ageing and the pathophysiology of numerous diseases including neurodegenerative disease, cancers, metabolic disorders and cardiovascular diseases. In the following review we will provide insights into the role of systems biology in nutritional research and focus on transcriptomic, proteomic and metabolomics studies that have demonstrated the ability of functional foods and their bioactive components to fight against oxidative damage and contribute to health benefits. © 2016 The British Pharmacological Society.

Fabrication and installation of the Solar Two central receiver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Litwin, R.Z.; Rogers, R.D.

The heart of the Solar Two power plant is the molten salt central receiver that has been designed, fabricated, and installed over an 18 month schedule. During this time, the receiver system from Solar One was also completely disassembled and removed. The receiver tower structure, for the most part, was left intact because Solar Two was designed to fit this structure such that construction time and costs could be minimized. In order to meet this aggressive schedule, receiver panel fabrication required the parallel production of many components. The sequence for assembly of the four major receiver panel components (i.e., tubes,more » header assembly, strongback, and header oven covers) and key fabrication activities such as welding are described. Once the receiver panels were complete, their installation at the site was begun, and the order in which receiver system components were installed in the tower is described. The completion of the Solar Two receiver proved the fabricability of this important system. However, successful operation of the system at Solar Two is needed to demonstrate the technical feasibility of the molten salt central receiver concept.« less

The contribution of temporary storage and executive processes to category learning.

PubMed

Wang, Tengfei; Ren, Xuezhu; Schweizer, Karl

2015-09-01

Three distinctly different working memory processes, temporary storage, mental shifting and inhibition, were proposed to account for individual differences in category learning. A sample of 213 participants completed a classic category learning task and two working memory tasks that were experimentally manipulated for tapping specific working memory processes. Fixed-links models were used to decompose data of the category learning task into two independent components representing basic performance and improvement in performance in category learning. Processes of working memory were also represented by fixed-links models. In a next step the three working memory processes were linked to components of category learning. Results from modeling analyses indicated that temporary storage had a significant effect on basic performance and shifting had a moderate effect on improvement in performance. In contrast, inhibition showed no effect on any component of the category learning task. These results suggest that temporary storage and the shifting process play different roles in the course of acquiring new categories. Copyright © 2015 Elsevier B.V. All rights reserved.

Enhancing links between visual short term memory, visual attention and cognitive control processes through practice: An electrophysiological insight.

PubMed

Fuggetta, Giorgio; Duke, Philip A

2017-05-01

The operation of attention on visible objects involves a sequence of cognitive processes. The current study firstly aimed to elucidate the effects of practice on neural mechanisms underlying attentional processes as measured with both behavioural and electrophysiological measures. Secondly, it aimed to identify any pattern in the relationship between Event-Related Potential (ERP) components which play a role in the operation of attention in vision. Twenty-seven participants took part in two recording sessions one week apart, performing an experimental paradigm which combined a match-to-sample task with a memory-guided efficient visual-search task within one trial sequence. Overall, practice decreased behavioural response times, increased accuracy, and modulated several ERP components that represent cognitive and neural processing stages. This neuromodulation through practice was also associated with an enhanced link between behavioural measures and ERP components and with an enhanced cortico-cortical interaction of functionally interconnected ERP components. Principal component analysis (PCA) of the ERP amplitude data revealed three components, having different rostro-caudal topographic representations. The first component included both the centro-parietal and parieto-occipital mismatch triggered negativity - involved in integration of visual representations of the target with current task-relevant representations stored in visual working memory - loaded with second negative posterior-bilateral (N2pb) component, involved in categorising specific pop-out target features. The second component comprised the amplitude of bilateral anterior P2 - related to detection of a specific pop-out feature - loaded with bilateral anterior N2, related to detection of conflicting features, and fronto-central mismatch triggered negativity. The third component included the parieto-occipital N1 - related to early neural responses to the stimulus array - which loaded with the second negative posterior-contralateral (N2pc) component, mediating the process of orienting and focusing covert attention on peripheral target features. We discussed these three components as representing different neurocognitive systems modulated with practice within which the input selection process operates. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Identification of Quorum Sensing Signal Molecule of Lactobacillus delbrueckii subsp. bulgaricus.

PubMed

Pang, Xiaoyang; Liu, Cuiping; Lyu, Pengcheng; Zhang, Shuwen; Liu, Lu; Lu, Jing; Ma, Changlu; Lv, Jiaping

2016-12-14

Many bacteria in nature use quorum sensing (QS) to regulate gene expression. The quorum sensing system plays critical roles in the adaptation of bacteria to the surrounding environment. Previous studies have shown that during high-density fermentation, the autolysis of lactic acid bacteria was regulated by the QS system, and the two-component system (TCS, LBUL_RS00115/LBUL_RS00110) is involved in the autolysis of Lactobacillus delbrueckii subsp. bulgaricus. However, the QS signal molecule, which regulates this pathway, has not been identified. In this study, we compared the genome of Lactobacillus bulgaricus ATCC BAA-365 with the locus of seven lactobacillus QS systems; the position of the QS signal molecule of Lactobacillus bulgaricus ATCC BAA-365 was predicted by bioinformatics tool. Its function was identified by in vitro experiments. Construction of TCS mutant by gene knockout of LBUL_RS00115 confirmed that the signal molecule regulates the density of the flora by the TCS (LBUL_RS00115/LBUL_RS00110). This study indicated that quorum quenching and inhibition based on the signal molecule might serve as an approach to reduce the rate of autolysis of LAB and increase the number of live bacteria in fermentation.

Development of a Bio-nanobattery for Distributed Power Storage Systems

NASA Technical Reports Server (NTRS)

King, Glen C.; Choi, Sang H.; Chu, Sang-Hyon; Kim, Jae-Woo; Park, Yeonjoon; Lillehei, Peter; Watt, Gerald D.; Davis, Robert; Harb, John N.

2004-01-01

Currently available power storage systems, such as those used to supply power to microelectronic devices, typically consist of a single centralized canister and a series of wires to supply electrical power to where it is needed in a circuit. As the size of electrical circuits and components become smaller, there exists a need for a distributed power system to reduce Joule heating, wiring, and to allow autonomous operation of the various functions performed by the circuit. Our research is being conducted to develop a bio-nanobattery using ferritins reconstituted with both an iron core (Fe-ferritin) and a cobalt core (Co-ferritin). Both Co-ferritin and Fe-ferritin were synthesized and characterized as candidates for the bio-nanobattery. The reducing capability was determined as well as the half-cell electrical potentials, indicating an electrical output of nearly 0.5 V for the battery cell. Ferritins having other metallic cores are also being investigated, in order to increase the overall electrical output. Two dimensional ferritin arrays were also produced on various substrates, demonstrating the necessary building blocks for the bio-nanobattery. The bio-nanobattery will play a key role in moving to a distributed power storage system for electronic applications.

Prescribed burning consumes key forest structural components: implications for landscape heterogeneity.

PubMed

Holland, Greg J; Clarke, Michael F; Bennett, Andrew F

2017-04-01

Prescribed burning to achieve management objectives is a common practice in fire-prone regions worldwide. Structural components of habitat that are combustible and slow to develop are particularly susceptible to change associated with prescribed burning. We used an experimental, "whole-landscape" approach to investigate the effect of differing patterns of prescribed burning on key habitat components (logs, stumps, dead trees, litter cover, litter depth, and understorey vegetation). Twenty-two landscapes (each ~100 ha) were selected in a dry forest ecosystem in southeast Australia. Experimental burns were conducted in 16 landscapes (stratified by burn extent) while six served as untreated controls. We measured habitat components prior to and after burning. Landscape burn extent ranged from 22% to 89% across the 16 burn treatments. With the exception of dead standing trees (no change), all measures of habitat components declined as a consequence of burning. The degree of loss increased as the extent to which a landscape was burned also increased. Prescribed burning had complex effects on the spatial heterogeneity (beta diversity) of structural components within landscapes. Landscapes that were more heterogeneous pre-fire were homogenized by burning, while those that were more homogenous pre-fire tended to display greater differentiation post-burning. Thus, the notion that patch mosaic burning enhances heterogeneity at the landscape-scale depends on prior conditions. These findings have important management implications. Where prescribed burns must be undertaken, effects on important resources can be moderated via control of burn characteristics (e.g., burn extent). Longer-term impacts of prescribed burning will be strongly influenced by the return interval, given the slow rate at which some structural components accumulate (decades to centuries). Management of habitat structural components is important given the critical role they play in (1) provision of habitat resources for diverse organisms, (2) retention of moisture and nutrients in otherwise dry, low-productivity systems, and (3) carbon storage. © 2016 by the Ecological Society of America.

Design of biomass management systems and components for closed loop life support systems

NASA Technical Reports Server (NTRS)

Nevill, Gale E., Jr.

1991-01-01

The design of a biomass management system (BMS) for use in a closed loop support system is presented by University of Florida students as the culmination of two design courses. The report is divided into two appendixes, each presenting the results of one of the design courses. The first appendix discusses the preliminary design of the biomass management system and is subdivided into five subsystems: (1) planting and harvesting, (2) food management, (3) resource recovery, (4) refurbishing, and (5) transport. Each subsystem is investigated for possible solutions to problems, and recommendations and conclusions for an integrated BMS are discussed. The second appendix discusses the specific design of components for the BMS and is divided into three sections: (1) a sectored plant growth unit with support systems, (2) a container and receiving mechanism, and (3) an air curtain system for fugitive particle control. In this section components are designed, fabricated, and tested.

Playful Learning and Montessori Education

ERIC Educational Resources Information Center

Lillard, Angeline S.

2013-01-01

Although Montessori education is often considered a form of playful learning, Maria Montessori herself spoke negatively about a major component of playful learning--pretend play, or fantasy--for young children. In this essay, the author discusses this apparent contradiction: how and why Montessori education includes elements of playful learning…

Two-path plasmonic interferometer with integrated detector

DOEpatents

Dyer, Gregory Conrad; Shaner, Eric A.; Aizin, Gregory

2016-03-29

An electrically tunable terahertz two-path plasmonic interferometer with an integrated detection element can down convert a terahertz field to a rectified DC signal. The integrated detector utilizes a resonant plasmonic homodyne mixing mechanism that measures the component of the plasma waves in-phase with an excitation field that functions as the local oscillator in the mixer. The plasmonic interferometer comprises two independently tuned electrical paths. The plasmonic interferometer enables a spectrometer-on-a-chip where the tuning of electrical path length plays an analogous role to that of physical path length in macroscopic Fourier transform interferometers.

A Proposed Information Architecture for Telehealth System Interoperability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Warren, S.; Craft, R.L.; Parks, R.C.

1999-04-07

Telemedicine technology is rapidly evolving. Whereas early telemedicine consultations relied primarily on video conferencing, consultations today may utilize video conferencing, medical peripherals, store-and-forward capabilities, electronic patient record management software, and/or a host of other emerging technologies. These remote care systems rely increasingly on distributed, collaborative information technology during the care delivery process, in its many forms. While these leading-edge systems are bellwethers for highly advanced telemedicine, the remote care market today is still immature. Most telemedicine systems are custom-designed and do not interoperate with other commercial offerings. Users are limited to a set of functionality that a single vendor providesmore » and must often pay high prices to obtain this functionality, since vendors in this marketplace must deliver entire systems in order to compete. Besides increasing corporate research and development costs, this inhibits the ability of the user to make intelligent purchasing decisions regarding best-of-breed technologies. We propose a secure, object-oriented information architecture for telemedicine systems that promotes plug-and-play interaction between system components through standardized interfaces, communication protocols, messaging formats, and data definitions. In this architecture, each component functions as a black box, and components plug together in a lego-like fashion to achieve the desired device or system functionality. The architecture will support various ongoing standards work in the medical device arena.« less

The Arabidopsis endoplasmic reticulum associated degradation pathways are involved in the regulation of heat stress response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Lin-Mao; University of Chinese Academy of Sciences, Beijing; Lü, Shi-You

Abstracts: The Cytosolic Protein Response (CPR) in the cytosol and the Unfolded Protein Response (UPR) and ER-associated degradation (ERAD) in the endoplasmic reticulum are major pathways of the cellular proteostasis network. However, despite years of effort, how these protein quality control systems coordinated in vivo remains largely unknown, particularly in plants. In this study, the roles of two evolutionarily conserved ERAD pathways (DOA10 and HRD1) in heat stress response were investigated through reverse genetic approaches in Arabidopsis. Phenotypic analysis of the mutants showed that the two ERAD pathways additively play negative roles in heat tolerance, which was demonstrated by higher survivalmore » rate and lower electrolyte leakage in the loss of function mutants compared to the wild type plants. Importantly, gene expression analysis revealed that the mutant plants showed elevated transcriptional regulation of several downstream genes, including those encoding CPR and UPR marker genes, under both basal and heat stress conditions. Finally, multiple components of ERAD genes exhibited rapid response to increasing temperature. Taken together, our data not only unravels key insights into the crosstalk between different protein quality control processes, but also provides candidate genes to genetically improve plant heat tolerance in the future. - Highlights: • ERAD pathways cooperatively regulate plant thermotolerance. • ERAD pathways cooperatively regulate UPR and CPR. • ERAD components gene expression are upregulated by heat stress.« less

Dynamics of dissolved organic matter (DOM) in a typical inland lake of the Three Gorges Reservoir area: Fluorescent properties and their implications for dissolved mercury species.

PubMed

Jiang, Tao; Chen, Xueshuang; Wang, Dingyong; Liang, Jian; Bai, Weiyang; Zhang, Cheng; Wang, Qilei; Wei, Shiqiang

2018-01-15

Dissolved organic matter (DOM) plays an important environmental and ecological role in inland aquatic systems, including lakes. In this study, using fluorescence analysis, we investigated the seasonal dynamics of DOM characteristics in Changshou Lake, which is a typical inland lake in the Three Gorges Reservoir (TGR) area. We also discuss the environmental implications of DOM for mercury (Hg) dynamics. Based on the origins of two end-members, the variations in DOM observed in this study in Changshou Lake suggest that hydrological processes (e.g., terrestrial inputs resulting from runoff and humic-like component residences) and biological activities (e.g., microbial and algae growth) are the two main principal components controlling the seasonal dynamics of DOM characteristics. Furthermore, the dynamics of dissolved Hg co-varied with variations in DOM properties, rather than with dissolved organic carbon (DOC) concentrations. This indicates that the previously reported simple correlations between DOC and Hg were not comprehensive and may lead to misunderstanding the interactions between DOM and Hg. Therefore, we recommend that when using DOM-Hg correlations to evaluate the role of DOM in the environmental fate of Hg, especially in field investigations of the spatial and temporal distribution of Hg, the properties of DOM must be taken into account. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of L-serine uptake by human placental microvillous membrane vesicles and placental villous fragments.

PubMed

Brand, A P; Greenwood, S L; Glazier, J D; Bennett, E J; Godfrey, K M; Sibley, C P; Hanson, M A; Lewis, R M

2010-05-01

Both syncytiotrophoblast microvillous plasma membrane vesicles (MVM) and placental villous fragments are used to characterize the placental uptake of maternal substrate and to investigate changes in uptake associated with pathological conditions. However, the two techniques have not been directly compared. In this study uptake of (14)C-L-serine was compared in placental villous fragments and in MVM prepared from the same placentas. (14)C-L-serine uptake into MVM vesicles was mediated by System L and System A and smaller unidentified Na(+)-dependent and Na(+)-independent components. In villous fragments an unidentified Na(+)-dependent component mediated the majority of (14)C-L-serine uptake followed by System A and System L. The unidentified Na(+)-independent component of L-serine uptake was not detected in villous fragments. The ratio of System A activity to System L activity was similar in villous fragments and MVM vesicles. However, the unidentified Na(+)-dependent component in villous fragments was significantly higher than that in MVM vesicles. This indicates that the main differences in serine uptake mechanisms identified using the two techniques were not due to differences in System A and System L activity but to differences in the unidentified Na(+)-dependent component. This study suggests that uptake of L-serine into MVM vesicles and villous fragments via Systems A and L is comparable, but that this is not true for all components of L-serine uptake. (c) 2010 Elsevier Ltd. All rights reserved.

The β Pictoris association low-mass members: Membership assessment, rotation period distribution, and dependence on multiplicity

NASA Astrophysics Data System (ADS)

Messina, S.; Lanzafame, A. C.; Malo, L.; Desidera, S.; Buccino, A.; Zhang, L.; Artemenko, S.; Millward, M.; Hambsch, F.-J.

2017-10-01

Context. Low-mass members of young loose stellar associations and open clusters exhibit a wide spread of rotation periods. Such a spread originates from the distributions of masses and initial rotation periods. However, multiplicity can also play a significant role. Aims: We aim to investigate the role played by physical companions in multiple systems in shortening the primordial disk lifetime, anticipating the rotation spin up with respect to single stars. Methods: We have compiled the most extensive list to date of low-mass bona fide and candidate members of the young 25-Myr β Pictoris association. We have measured from our own photometric time series or from archival time series the rotation periods of almost all members. In a few cases the rotation periods were retrieved from the literature. We used updated UVWXYZ components to assess the membership of the whole stellar sample. Thanks to the known basic properties of most members we built the rotation period distribution distinguishing between bona fide members and candidate members and according to their multiplicity status. Results: We find that single stars and components of multiple systems in wide orbits (>80 AU) have rotation periods that exhibit a well defined sequence arising from mass distribution with some level of spread likely arising from initial rotation period distribution. All components of multiple systems in close orbits (<80 AU) have rotation periods that are significantly shorter than their equal-mass single counterparts. For these close components of multiple systems a linear dependence of rotation rate on separation is only barely detected. A comparison with the younger 13 Myr h Per cluster and with the older 40-Myr open clusters and stellar associations NGC 2547, IC 2391, Argus, and IC 2602 and the 130-Myr Pleiades shows that whereas the evolution of F-G stars is well reproduced by angular momentum evolution models, this is not the case for the slow K and early-M stars. Finally, we find that the amplitude of their light curves is correlated neither with rotation nor with mass. Conclusions: Once single stars and wide components of multiple systems are separated from close components of multiple systems, the rotation period distributions exhibit a well defined dependence on mass that allows us to make a meaningful comparison with similar distributions of either younger or older associations and clusters. Such cleaned distributions allow us to use the stellar rotation period meaningfully as an age indicator for F and G type stars. Tables 2 and 3 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/607/A3

The Cascadia Paradox: Understanding Mantle Flow in the Cascadia Subduction System

NASA Astrophysics Data System (ADS)

Long, M. D.

2015-12-01

The pattern of mantle flow in subduction systems, and the processes that control the mantle flow field, is a fundamental but still poorly understood aspect of subduction dynamics. Mantle flow plays a key role in controlling the transport of volatiles and melt in the wedge, deformation of the overriding plate, mass transfer between the upper and lower mantle, and the morphology and dynamics of slabs. The Cascadia subduction zone provides a compelling system in which to understand the controls on mantle flow, particularly given the dense geophysical observations provided by EarthScope, GeoPRISMS, the Cascadia Initiative, and related efforts. Cascadia is a particularly intriguing system because observations of seismic anisotropy, which provide relatively direct constraints on mantle flow, seem to yield contradictory views of the mantle flow field in different parts of the system. Observations of seismic anisotropy on the overriding plate apparently require a significant component of three-dimensional, toroidal flow around the slab edge, while new observations from offshore stations are compellingly explained with a simple two-dimensional entrained flow model. Recent evidence from seismic tomography for the fragmentation of the Cascadia slab at depth provides a further puzzle: how can a fragmented slab provide a driving force for either two-dimensional entrained flow or three-dimensional toroidal flow due to slab rollback? I will present a synthesis of recent observations of seismic anisotropy in the Cascadia subduction system, and how they can be integrated with constraints from geodynamical modeling, geochemistry, and the history and timing of Pacific Northwest volcanism. I will discuss the compelling but contradictory evidence for each of the endmember mantle flow models (two-dimensional entrained flow vs. three-dimensional toroidal flow) and explore possible avenues for resolving the Cascadia Paradox.

A closed-loop control-loading system

NASA Technical Reports Server (NTRS)

Ashworth, B. R.; Parrish, R. V.

1979-01-01

Langley Differential Maneuvering Simulator (DMS) realistically simulates two aircraft operating in differential mode. It consists of two identical fixed-base cockpits and dome projection systems. Each projection system consists of sky/Earth projector and target-image generator and projector. Although programmable control forces are small part of overall system, they play large role in providing pilot with kinesthetic cues.

Strategy Revealing Phenotypic Differences among Synthetic Oscillator Designs

PubMed Central

2015-01-01

Considerable progress has been made in identifying and characterizing the component parts of genetic oscillators, which play central roles in all organisms. Nonlinear interaction among components is sufficiently complex that mathematical models are required to elucidate their elusive integrated behavior. Although natural and synthetic oscillators exhibit common architectures, there are numerous differences that are poorly understood. Utilizing synthetic biology to uncover basic principles of simpler circuits is a way to advance understanding of natural circadian clocks and rhythms. Following this strategy, we address the following questions: What are the implications of different architectures and molecular modes of transcriptional control for the phenotypic repertoire of genetic oscillators? Are there designs that are more realizable or robust? We compare synthetic oscillators involving one of three architectures and various combinations of the two modes of transcriptional control using a methodology that provides three innovations: a rigorous definition of phenotype, a procedure for deconstructing complex systems into qualitatively distinct phenotypes, and a graphical representation for illuminating the relationship between genotype, environment, and the qualitatively distinct phenotypes of a system. These methods provide a global perspective on the behavioral repertoire, facilitate comparisons of alternatives, and assist the rational design of synthetic gene circuitry. In particular, the results of their application here reveal distinctive phenotypes for several designs that have been studied experimentally as well as a best design among the alternatives that has yet to be constructed and tested. PMID:25019938

Optical Flares and a Long-lived Dark Spot on a Cool Shallow Contact Binary

NASA Astrophysics Data System (ADS)

Qian, S.-B.; Wang, J.-J.; Zhu, L.-Y.; Snoonthornthum, B.; Wang, L.-Z.; Zhao, E. G.; Zhou, X.; Liao, W.-P.; Liu, N.-P.

2014-05-01

W UMa-type stars are contact systems where both cool components fill the critical Roche lobes and share a common convective envelope. Long and unbroken time-series photometry is expected to play an important role in their origin and activity. The newly discovered short-period W UMa-type star, CSTAR 038663, was monitored continuously by Chinese Small Telescope ARray (CSTAR) in Antarctica during the winters of 2008 and 2010. There were 15 optical flares recorded in the i band during the winter of 2010. This was the first time such flares were detected from a W UMa-type star. By analyzing the nearly unbroken photometric data from 2008, it is discovered that CSTAR 038663 is a W-type shallow contact binary system (f = 10.6(± 2.9)%) with a high mass ratio of q = 1.12(± 0.01), where the less massive component is slightly hotter than the more massive one. The asymmetric light curves are explained by the presence of a dark spot on the more massive component. Its temperature is about 800 K lower than the stellar photosphere and it covers 2.1% of the total photospheric surface. The lifetime of the dark spot is longer than 116 days. Using 725 eclipse times, we found that the observed-calculated (O-C) curve may show a cyclic variation that is explained by the presence of a close-in third body. Both the shallow contact configuration and the extremely high mass ratio suggest that CSTAR 038663 is presently evolving into a contact system with little mass transfer. The formation and evolution is driven by the loss of angular momentum via magnetic braking, and the close-in companion star is expected to play an important role, removing angular momentum from the central eclipsing binary.

Assessing spatial coupling in complex population dynamics using mutual prediction and continuity statistics

USGS Publications Warehouse

Nichols, J.M.; Moniz, L.; Nichols, J.D.; Pecora, L.M.; Cooch, E.

2005-01-01

A number of important questions in ecology involve the possibility of interactions or ?coupling? among potential components of ecological systems. The basic question of whether two components are coupled (exhibit dynamical interdependence) is relevant to investigations of movement of animals over space, population regulation, food webs and trophic interactions, and is also useful in the design of monitoring programs. For example, in spatially extended systems, coupling among populations in different locations implies the existence of redundant information in the system and the possibility of exploiting this redundancy in the development of spatial sampling designs. One approach to the identification of coupling involves study of the purported mechanisms linking system components. Another approach is based on time series of two potential components of the same system and, in previous ecological work, has relied on linear cross-correlation analysis. Here we present two different attractor-based approaches, continuity and mutual prediction, for determining the degree to which two population time series (e.g., at different spatial locations) are coupled. Both approaches are demonstrated on a one-dimensional predator?prey model system exhibiting complex dynamics. Of particular interest is the spatial asymmetry introduced into the model as linearly declining resource for the prey over the domain of the spatial coordinate. Results from these approaches are then compared to the more standard cross-correlation analysis. In contrast to cross-correlation, both continuity and mutual prediction are clearly able to discern the asymmetry in the flow of information through this system.

Immediate and heterogeneous response of the LiaFSR two-component system of Bacillus subtilis to the peptide antibiotic bacitracin.

PubMed

Kesel, Sara; Mader, Andreas; Höfler, Carolin; Mascher, Thorsten; Leisner, Madeleine

2013-01-01

Two-component signal transduction systems are one means of bacteria to respond to external stimuli. The LiaFSR two-component system of Bacillus subtilis consists of a regular two-component system LiaRS comprising the core Histidine Kinase (HK) LiaS and the Response Regulator (RR) LiaR and additionally the accessory protein LiaF, which acts as a negative regulator of LiaRS-dependent signal transduction. The complete LiaFSR system was shown to respond to various peptide antibiotics interfering with cell wall biosynthesis, including bacitracin. Here we study the response of the LiaFSR system to various concentrations of the peptide antibiotic bacitracin. Using quantitative fluorescence microscopy, we performed a whole population study analyzed on the single cell level. We investigated switching from the non-induced 'OFF' state into the bacitracin-induced 'ON' state by monitoring gene expression of a fluorescent reporter from the RR-regulated liaI promoter. We found that switching into the 'ON' state occurred within less than 20 min in a well-defined switching window, independent of the bacitracin concentration. The switching rate and the basal expression rate decreased at low bacitracin concentrations, establishing clear heterogeneity 60 min after bacitracin induction. Finally, we performed time-lapse microscopy of single cells confirming the quantitative response as obtained in the whole population analysis for high bacitracin concentrations. The LiaFSR system exhibits an immediate, heterogeneous and graded response to the inducer bacitracin in the exponential growth phase.

Comprehensive Review of Nutritional Components for Occupational Health Nurses-Part 1.

PubMed

Toothaker, Rebecca; Chikotas, Noreen

2018-05-01

This article, the first in a two-part series, reviews and examines the components of clinical nutrition. In Part 1, the authors introduce the concept of nutrition and the role it plays in supporting healthy employees, current guidelines, and recommendations for determining healthy eating and the nutritional component of carbohydrates. In Part 2, the components of fats, proteins, vitamins, minerals, and water, and a resource guide are provided for the occupational health nurse to assist in the implementation of employee education in the area of healthy nutrition. The intent of the articles is to acquaint and inform occupational health nurses on the current guidelines for healthy eating so they can better appraise their employee population, thus creating a healthier workforce. The information provided is not all-inclusive on the topics discussed, but provides a foundation to understand the requirements for a healthier workforce.

Ultrasonic Fluid Quality Sensor System

DOEpatents

Gomm, Tyler J.; Kraft, Nancy C.; Phelps, Larry D.; Taylor, Steven C.

2003-10-21

A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.

Ultrasonic fluid quality sensor system

DOEpatents

Gomm, Tyler J.; Kraft, Nancy C.; Phelps, Larry D.; Taylor, Steven C.

2002-10-08

A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.

Automated Grading of Rough Hardwood Lumber

Treesearch

Richard W. Conners; Tai-Hoon Cho; Philip A. Araman

1989-01-01

Any automatic hardwood grading system must have two components. The first of these is a computer vision system for locating and identifying defects on rough lumber. The second is a system for automatically grading boards based on the output of the computer vision system. This paper presents research results aimed at developing the first of these components. The...

Neutrophil Extracellular Traps and Its Implications in Inflammation: An Overview

PubMed Central

Delgado-Rizo, Vidal; Martínez-Guzmán, Marco A.; Iñiguez-Gutierrez, Liliana; García-Orozco, Alejandra; Alvarado-Navarro, Anabell; Fafutis-Morris, Mary

2017-01-01

In addition to physical barriers, neutrophils are considered a part of the first line of immune defense. They can be found in the bloodstream, with a lifespan of 6–8 h, and in tissue, where they can last up to 7 days. The mechanisms that neutrophils utilize for host defense are phagocytosis, degranulation, cytokine production, and, the most recently described, neutrophil extracellular trap (NET) production. NETs are DNA structures released due to chromatin decondensation and spreading, and they thus occupy three to five times the volume of condensed chromatin. Several proteins adhere to NETs, including histones and over 30 components of primary and secondary granules, among them components with bactericidal activity such as elastase, myeloperoxidase, cathepsin G, lactoferrin, pentraxin 3, gelatinase, proteinase 3, LL37, peptidoglycan-binding proteins, and others with bactericidal activity able to destroy virulence factors. Three models for NETosis are known to date. (a) Suicidal NETosis, with a duration of 2–4 h, is the best described model. (b) In vital NETosis with nuclear DNA release, neutrophils release NETs without exhibiting loss of nuclear or plasma membrane within 5–60 min, and it is independent of reactive oxygen species (ROS) and the Raf/MERK/ERK pathway. (c) The final type is vital NETosis with release of mitochondrial DNA that is dependent on ROS and produced after stimuli with GM-CSF and lipopolysaccharide. Recent research has revealed neutrophils as more sophisticated immune cells that are able to precisely regulate their granular enzymes release by ion fluxes and can release immunomodulatory cytokines and chemokines that interact with various components of the immune system. Therefore, they can play a key role in autoimmunity and in autoinflammatory and metabolic diseases. In this review, we intend to show the two roles played by neutrophils: as a first line of defense against microorganisms and as a contributor to the pathogenesis of various illnesses, such as autoimmune, autoinflammatory, and metabolic diseases. PMID:28220120

The autophagy interaction network of the aging model Podospora anserina.

PubMed

Philipp, Oliver; Hamann, Andrea; Osiewacz, Heinz D; Koch, Ina

2017-03-27

Autophagy is a conserved molecular pathway involved in the degradation and recycling of cellular components. It is active either as response to starvation or molecular damage. Evidence is emerging that autophagy plays a key role in the degradation of damaged cellular components and thereby affects aging and lifespan control. In earlier studies, it was found that autophagy in the aging model Podospora anserina acts as a longevity assurance mechanism. However, only little is known about the individual components controlling autophagy in this aging model. Here, we report a biochemical and bioinformatics study to detect the protein-protein interaction (PPI) network of P. anserina combining experimental and theoretical methods. We constructed the PPI network of autophagy in P. anserina based on the corresponding networks of yeast and human. We integrated PaATG8 interaction partners identified in an own yeast two-hybrid analysis using ATG8 of P. anserina as bait. Additionally, we included age-dependent transcriptome data. The resulting network consists of 89 proteins involved in 186 interactions. We applied bioinformatics approaches to analyze the network topology and to prove that the network is not random, but exhibits biologically meaningful properties. We identified hub proteins which play an essential role in the network as well as seven putative sub-pathways, and interactions which are likely to be evolutionary conserved amongst species. We confirmed that autophagy-associated genes are significantly often up-regulated and co-expressed during aging of P. anserina. With the present study, we provide a comprehensive biological network of the autophagy pathway in P. anserina comprising PPI and gene expression data. It is based on computational prediction as well as experimental data. We identified sub-pathways, important hub proteins, and evolutionary conserved interactions. The network clearly illustrates the relation of autophagy to aging processes and enables further specific studies to understand autophagy and aging in P. anserina as well as in other systems.

Building technolgies program. 1994 annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selkowitz, S.E.

1995-04-01

The objective of the Building Technologies program is to assist the U.S. building industry in achieving substantial reductions in building sector energy use and associated greenhouse gas emissions while improving comfort, amenity, health, and productivity in the building sector. We have focused our past efforts on two major building systems, windows and lighting, and on the simulation tools needed by researchers and designers to integrate the full range of energy efficiency solutions into achievable, cost-effective design solutions for new and existing buildings. In addition, we are now taking more of an integrated systems and life cycle perspective to create cost-effectivemore » solutions for more energy efficient, comfortable, and productive work and living environments. More than 30% of all energy use in buildings is attributable to two sources: windows and lighting. Together they account for annual consumer energy expenditures of more than $50 billion. Each affects not only energy use by other major building systems, but also comfort and productivity-factors that influence building economics far more than does direct energy consumption alone. Windows play a unique role in the building envelope, physically separating the conditioned space from the world outside without sacrificing vital visual contact. Throughout every space in a building, lighting systems facilitate a variety of tasks associated with a wide range of visual requirements while defining the luminous qualities of the indoor environment. Window and lighting systems are thus essential components of any comprehensive building science program.« less

FOREIGN BODY REACTION TO BIOMATERIALS

PubMed Central

Anderson, James M.; Rodriguez, Analiz; Chang, David T.

2008-01-01

The foreign body reaction composed of macrophages and foreign body giant cells is the end-stage response of the inflammatory and wound healing responses following implantation of a medical device, prosthesis, or biomaterial. A brief, focused overview of events leading to the foreign body reaction is presented. The major focus of this review is on factors that modulate the interaction of macrophages and foreign body giant cells on synthetic surfaces where the chemical, physical, and morphological characteristics of the synthetic surface are considered to play a role in modulating cellular events. These events in the foreign body reaction include protein adsorption, monocyte/macrophage adhesion, macrophage fusion to form foreign body giant cells, consequences of the foreign body response on biomaterials, and cross-talk between macrophages/foreign body giant cells and inflammatory/wound healing cells. Biomaterial surface properties play an important role in modulating the foreign body reaction in the first two to four weeks following implantation of a medical device, even though the foreign body reaction at the tissue/material interface is present for the in vivo lifetime of the medical device. An understanding of the foreign body reaction is important as the foreign body reaction may impact the biocompatibility (safety) of the medical device, prosthesis, or implanted biomaterial and may significantly impact short- and long-term tissue responses with tissue-engineered constructs containing proteins, cells, and other biological components for use in tissue engineering and regenerative medicine. Our perspective has been on the inflammatory and wound healing response to implanted materials, devices, and tissue-engineered constructs. The incorporation of biological components of allogeneic or xenogeneic origin as well as stem cells into tissue-engineered or regenerative approaches opens up a myriad of other challenges. An in depth understanding of how the immune system interacts with these cells and how biomaterials or tissue-engineered constructs influences these interactions may prove pivotal to the safety, biocompatibility, and function of the device or system under consideration. PMID:18162407

Team Training for Command and Control Systems. Volume IV. Recommendations for Simulation Facility.

DTIC Science & Technology

1982-04-01

free - play war gaming exercises. The tactical situation models should allow the researcher to specify certain relevant environmental conditions: weather...emphasizes dynamic free - play and task-oriented responses. The individualized CBT exercises would not necessarily replace or even reduce the amount of time...intercept exercises and bump-heads free - play , but they cannot currently be used to simulate larger-scale, two-sided, free - play engagements. 69 . All

Uptake of raft components into amyloid β-peptide aggregates and membrane damage.

PubMed

Sasahara, Kenji; Morigaki, Kenichi; Mori, Yasuko

2015-07-15

Amyloid aggregation and deposition of amyloid β-peptide (Aβ) are pathologic characteristics of Alzheimer's disease (AD). Recent reports have shown that the association of Aβ with membranes containing ganglioside GM1 (GM1) plays a pivotal role in amyloid deposition and the pathogenesis of AD. However, the molecular interactions responsible for membrane damage associated with Aβ deposition are not fully understood. In this study, we microscopically observed amyloid aggregation of Aβ in the presence of lipid vesicles and on a substrate-supported planar membrane containing raft components and GM1. The experimental system enabled us to observe lipid-associated aggregation of Aβ, uptake of the raft components into Aβ aggregates, and relevant membrane damage. The results indicate that uptake of raft components from the membrane into Aβ deposits induces macroscopic heterogeneity of the membrane structure. Copyright © 2015 Elsevier Inc. All rights reserved.

Sense and avoid technologies with applications to unmanned aircraft systems: Review and prospects

NASA Astrophysics Data System (ADS)

Yu, Xiang; Zhang, Youmin

2015-04-01

Unmanned Aircraft Systems (UASs) are becoming ever more promising over the last decade. The Sense and Avoid (S&A) system plays a profoundly important role in integrating UASs into the National Airspace System (NAS) with reliable and safe operations. After analyzing the manner of S&A system, this paper systematically presents an overview on the recent progress in S&A technologies in the sequence of fundamental functions/components of S&A in sensing techniques, decision making, path planning, and path following. The approaches to these four aspects are outlined and summarized, based on which the existing challenges and potential solutions are highlighted for facilitating the development of S&A systems.

Current Pressure Transducer Application of Model-based Prognostics Using Steady State Conditions

NASA Technical Reports Server (NTRS)

Teubert, Christopher; Daigle, Matthew J.

2014-01-01

Prognostics is the process of predicting a system's future states, health degradation/wear, and remaining useful life (RUL). This information plays an important role in preventing failure, reducing downtime, scheduling maintenance, and improving system utility. Prognostics relies heavily on wear estimation. In some components, the sensors used to estimate wear may not be fast enough to capture brief transient states that are indicative of wear. For this reason it is beneficial to be capable of detecting and estimating the extent of component wear using steady-state measurements. This paper details a method for estimating component wear using steady-state measurements, describes how this is used to predict future states, and presents a case study of a current/pressure (I/P) Transducer. I/P Transducer nominal and off-nominal behaviors are characterized using a physics-based model, and validated against expected and observed component behavior. This model is used to map observed steady-state responses to corresponding fault parameter values in the form of a lookup table. This method was chosen because of its fast, efficient nature, and its ability to be applied to both linear and non-linear systems. Using measurements of the steady state output, and the lookup table, wear is estimated. A regression is used to estimate the wear propagation parameter and characterize the damage progression function, which are used to predict future states and the remaining useful life of the system.

Chemical composition and antimicrobial activity of Satureja hortensis and Trachyspermum copticum essential oil

PubMed Central

Mahboubi, M; Kazempour, N

2011-01-01

Background and Objectives The aim of this study was to evaluate the chemical composition and antimicrobial activity of Satureja hortensis and Trachyspermum copticum essential oils against different kinds of microorganisms in vitro. Material and Methods The antimicrobial activity was evaluated by micro broth dilution assay and the chemical composition of essential oils was analyzed by GC and GC/MS. Results Thymol, p-cymene, γ-terpinene and carvacrol were the main components of S. hortensis oil while thymol, γ-terpinene, and o-cymene were the major components of T. copticum oil. Two essential oils exhibited strong antimicrobial activity but the antimicrobial activity of T. copticum oil was higher than that of S. hortensis oil. Conclusion Thymol as a main component of oils plays an important role in antimicrobial activity. PMID:22530088

The musculature and pupillary response of the great horned owl iris.

PubMed

Oliphant, L W; Johnson, M R; Murphy, C; Howland, H

1983-12-01

There is considerable confusion in the literature regarding the nature of the musculature of the avian iris. The most commonly held view is that both the sphincter and dilator are striated. The iris of the Great Horned Owl (Bubo virginianus) has a complex iridial musculature consisting of three circumferential components (a myoepithelium, smooth muscle and striated muscle) and two radial components (a well-developed myoepithelium and a few striated fibers). On the basis of the anatomy and relative development of these components, and a quantitative analysis of the pupillary reflex, it is proposed that the circumferential striated muscle is the primary pupillary constrictor and radial myoepithelium is the primary dilator. The annular band of smooth muscle may play an important role in maintaining pupillary size.

Two Components of Aversive Memory in Drosophila, Anesthesia-Sensitive and Anesthesia-Resistant Memory, Require Distinct Domains Within the Rgk1 Small GTPase.

PubMed

Murakami, Satoshi; Minami-Ohtsubo, Maki; Nakato, Ryuichiro; Shirahige, Katsuhiko; Tabata, Tetsuya

2017-05-31

Multiple components have been identified that exhibit different stabilities for aversive olfactory memory in Drosophila These components have been defined by behavioral and genetic studies and genes specifically required for a specific component have also been identified. Intermediate-term memory generated after single cycle conditioning is divided into anesthesia-sensitive memory (ASM) and anesthesia-resistant memory (ARM), with the latter being more stable. We determined that the ASM and ARM pathways converged on the Rgk1 small GTPase and that the N-terminal domain-deleted Rgk1 was sufficient for ASM formation, whereas the full-length form was required for ARM formation. Rgk1 is specifically accumulated at the synaptic site of the Kenyon cells (KCs), the intrinsic neurons of the mushroom bodies, which play a pivotal role in olfactory memory formation. A higher than normal Rgk1 level enhanced memory retention, which is consistent with the result that Rgk1 suppressed Rac-dependent memory decay; these findings suggest that rgk1 bolsters ASM via the suppression of forgetting. We propose that Rgk1 plays a pivotal role in the regulation of memory stabilization by serving as a molecular node that resides at KC synapses, where the ASM and ARM pathway may interact. SIGNIFICANCE STATEMENT Memory consists of multiple components. Drosophila olfactory memory serves as a fundamental model with which to investigate the mechanisms that underlie memory formation and has provided genetic and molecular means to identify the components of memory, namely short-term, intermediate-term, and long-term memory, depending on how long the memory lasts. Intermediate memory is further divided into anesthesia-sensitive memory (ASM) and anesthesia-resistant memory (ARM), with the latter being more stable. We have identified a small GTPase in Drosophila , Rgk1, which plays a pivotal role in the regulation of olfactory memory stability. Rgk1 is required for both ASM and ARM. Moreover, N-terminal domain-deleted Rgk1 was sufficient for ASM formation, whereas the full-length form was required for ARM formation. Copyright © 2017 the authors 0270-6474/17/375496-•$15.00/0.

Phase Diagram of Fractional Quantum Hall Effect of Composite Fermions in Multi-Component Systems

NASA Astrophysics Data System (ADS)

Coimbatore Balram, Ajit; Töke, Csaba; Wójs, Arkadiusz; Jain, Jainendra

2015-03-01

The fractional quantum Hall effect (FQHE) of composite fermions (CFs) produces delicate states arising from a weak residual interaction between CFs. We study the spin phase diagram of these states, motivated by the recent experimental observation by Liu et al. of several spin-polarization transitions at 4/5, 5/7, 6/5, 9/7, 7/9, 8/11 and 10/13 in GaAs systems. We show that the FQHE of CFs is much more prevalent in multicomponent systems, and consider the feasibility of such states for systems with N components for an SU(N) symmetric interaction. Our results apply to GaAs quantum wells, wherein electrons have two components, to AlAs quantum wells and graphene, wherein electrons have four components (two spins and two valleys), and to an H-terminated Si(111) surface, which can have six components. We provide a fairly comprehensive list of possible incompressible FQH states of CFs, their SU(N) spin content, their energies, and their phase diagram as a function of the generalized ``Zeeman'' energy. The results are in good agreement with available experiments. DOE Grant No. DE-SC0005042, Hungarian Scientific Research Funds No. K105149 (CT), the Polish NCN grant 2011/01/B/ST3/04504 and the EU Marie Curie Grant PCIG09-GA-2011-294186.

Toddlers' Complex Communication: Playfulness from a Secure Base

ERIC Educational Resources Information Center

Alcock, Sophie

2013-01-01

Attachment theory is presented in this article as involving embodied relational processes within complex relational systems. Two narrative-like "events" are represented to illustrate very young children playfully relating -- connecting and communicating inter- and intrasubjectively. The ethnographic-inspired research methods included…

The sulfiredoxin-peroxiredoxin (Srx-Prx) axis in cell signal transduction and cancer development.

PubMed

Mishra, Murli; Jiang, Hong; Wu, Lisha; Chawsheen, Hedy A; Wei, Qiou

2015-10-01

Redox signaling is a critical component of cell signaling pathways that are involved in the regulation of cell growth, metabolism, hormone signaling, immune regulation and variety of other physiological functions. Peroxiredoxin (Prx) is a family of thiol-based peroxidase that acts as a regulator of redox signaling. Members of Prx family can act as antioxidants and chaperones. Sulfiredoxin (Srx) is an antioxidant protein that exclusively reduces over-oxidized typical 2-Cys Prx. Srx has different affinities for individual Prx and it also catalyzes the deglutathionylation of variety of substrates. Individual component of the Srx-Prx system plays critical role in carcinogenesis by modulating cell signaling pathways involved in cell proliferation, migration and metastasis. Expression levels of individual component of the Srx-Prx axis have been correlated with patient survival outcome in multiple cancer types. This review will summarize the molecular basis of differences in the affinity of Srx for individual Prx and the role of individual component of the Srx-Prx system in tumor progression and metastasis. This enhanced understanding of molecular aspects of Srx-Prx interaction and its role in cell signal transduction will help define the Srx-Prx system as a future therapeutic target in human cancer. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Speciation and Sources of Brown Carbon in Precipitation at Seoul, Korea: Insights from Excitation-Emission Matrix Spectroscopy and Carbon Isotopic Analysis.

PubMed

Yan, Ge; Kim, Guebuem

2017-10-17

Brown carbon (BrC) plays a significant role in the Earth's radiative balance, yet its sources and chemical composition remain poorly understood. In this work, we investigated BrC in the atmospheric environment of Seoul by characterizing dissolved organic matter in precipitation using excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC). The two independent fluorescent components identified by PARAFAC were attributed to humic-like substance (HULIS) and biologically derived material based on their significant correlations with measured HULIS isolated using solid-phase extraction and total hydrolyzable tyrosine. The year-long observation shows that HULIS contributes to 66 ± 13% of total fluorescence intensity of our samples on average. By using dual carbon ( 13 C and 14 C) isotopic analysis conducted on isolated HULIS, the HULIS fraction of BrC was found to be primarily derived from biomass burning and emission of terrestrial biogenic gases and particles (>70%), with minor contributions from fossil-fuel combustion. The knowledge derived from this study could contribute to the establishment of a characterizing system of BrC components identified by EEM spectroscopy. Our work demonstrates that, EEM fluorescence spectroscopy is a powerful tool in BrC study, on the basis of its chromophore resolving power, allowing investigation into individual components of BrC by other organic matter characterization techniques.

Comparative Analysis of Predicted Plastid-Targeted Proteomes of Sequenced Higher Plant Genomes

PubMed Central

Schaeffer, Scott; Harper, Artemus; Raja, Rajani; Jaiswal, Pankaj; Dhingra, Amit

2014-01-01

Plastids are actively involved in numerous plant processes critical to growth, development and adaptation. They play a primary role in photosynthesis, pigment and monoterpene synthesis, gravity sensing, starch and fatty acid synthesis, as well as oil, and protein storage. We applied two complementary methods to analyze the recently published apple genome (Malus × domestica) to identify putative plastid-targeted proteins, the first using TargetP and the second using a custom workflow utilizing a set of predictive programs. Apple shares roughly 40% of its 10,492 putative plastid-targeted proteins with that of the Arabidopsis (Arabidopsis thaliana) plastid-targeted proteome as identified by the Chloroplast 2010 project and ∼57% of its entire proteome with Arabidopsis. This suggests that the plastid-targeted proteomes between apple and Arabidopsis are different, and interestingly alludes to the presence of differential targeting of homologs between the two species. Co-expression analysis of 2,224 genes encoding putative plastid-targeted apple proteins suggests that they play a role in plant developmental and intermediary metabolism. Further, an inter-specific comparison of Arabidopsis, Prunus persica (Peach), Malus × domestica (Apple), Populus trichocarpa (Black cottonwood), Fragaria vesca (Woodland Strawberry), Solanum lycopersicum (Tomato) and Vitis vinifera (Grapevine) also identified a large number of novel species-specific plastid-targeted proteins. This analysis also revealed the presence of alternatively targeted homologs across species. Two separate analyses revealed that a small subset of proteins, one representing 289 protein clusters and the other 737 unique protein sequences, are conserved between seven plastid-targeted angiosperm proteomes. Majority of the novel proteins were annotated to play roles in stress response, transport, catabolic processes, and cellular component organization. Our results suggest that the current state of knowledge regarding plastid biology, preferentially based on model systems is deficient. New plant genomes are expected to enable the identification of potentially new plastid-targeted proteins that will aid in studying novel roles of plastids. PMID:25393533

[Comparative analysis of the efficacy of a playful-narrative program to teach mathematics at pre-school level].

PubMed

Gil Llario, M D; Vicent Catalá, Consuelo

2009-02-01

Comparative analysis of the efficacy of a playful-narrative program to teach mathematics at pre-school level. In this paper, the effectiveness of a programme comprising several components that are meant to consolidate mathematical concepts and abilities at the pre-school level is analyzed. The instructional methodology of this programme is compared to other methodologies. One-hundred 5-6 year-old children made up the sample that was distributed in the following conditions: (1) traditional methodology; (2) methodology with perceptual and manipulative components, and (3) methodology with language and playful components. Mathematical competence was assessed with the Mathematical Criterial Pre-school Test and the subtest of quantitative-numeric concepts of BADyG. Participants were evaluated before and after the academic course during which they followed one of these methodologies. The results show that the programme with language and playful components is more effective than the traditional methodology (p<.000) and also more effective than the perceptual and manipulative methodology (p<.000). Implications of the results for instructional practices are analyzed.

Liquid-vapor phase equilibria of three-component systems of propanol-2-propanoic acid esters

NASA Astrophysics Data System (ADS)

Suntsov, Yu. K.; Goryunov, V. A.; Chuikov, A. M.

2017-12-01

The boiling points of solutions of three-component systems formed by propanol-2 and propanoic acid esters are measured at different pressures by means of ebulliometry. The coefficients of the activity of the solutions' components are measured using Wilson and nonrandom two-liquid (NRTL) equations. The results from calculations are in line with the experimental data.

The Dynamic Systems Approach as Metatheory for Developmental Psychology

ERIC Educational Resources Information Center

Witherington, David C.

2007-01-01

The dynamic systems perspective has been touted as an integrative metatheoretical framework for the study of stability and change in development. However, two dynamic systems camps exist with respect to the role higher-order form, once emergent, plays in the process of development. This paper evaluates these two camps in terms of the overarching…