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Sample records for air-liquid interface ali

  1. Critical Evaluation of Air-Liquid Interface Exposure Devices for In Vitro Assessment of Atmospheric Pollutants

    EPA Science Inventory

    Exposure of cells to atmospheric pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of attached cells submerged in liquid medium. However, there is still limited understanding of the ideal ALI device design features that permit reproducible a...

  2. Evaluation of air-liquid interface exposure systems for in vitro assessment of airborne pollutants

    EPA Science Inventory

    Exposure of cells to airborne pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of submerged cells. The published literature, however, describes irreproducible and/or unrealistic experimental conditions using ALI systems. We have compared fi...

  3. Hydrodynamical entrapment of ciliates at the air-liquid interface

    NASA Astrophysics Data System (ADS)

    Ferracci, Jonathan; Ueno, Hironori; Numayama-Tsuruta, Keiko; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

    2012-11-01

    We found the new phenomenon of the entrapment of ciliates at the air-water interface, though they are not trapped by a solid interface. We first characterize the behaviours of cells at the interface by comparing it to those away from interfaces. The results showed that the cell's swimming velocity is considerably reduced at the air-water interface. In order to experimentally verify the possible physiological causes of the entrapment, we observed their behaviours in absence of positive chemotaxis for oxygen and the negative geotaxis. The results illustrated that the entrapment phenomenon was not dependent on these physiological conditions. The experiments using surfactant revealed that the entrapment phenomenon was strongly affected by the velocity-stress conditions at the interface. This fact was confirmed numerically by a boundary element method, i.e. the stress-free condition at the air-liquid interface is one of the main mechanisms of the entrapment phenomenon found in the experiments. Since the entrapment phenomenon found in this study affects the cell-cell interactions and the mass transport at the interface, the knowledge obtained in this study is useful for better understanding the complex behaviours of swimming microorganisms in nature. PhD student in the Physiological Flow Studies Laboratory.

  4. Optimization of an air-liquid interface exposure system for assessing toxicity of airborne nanoparticles.

    PubMed

    Latvala, Siiri; Hedberg, Jonas; Möller, Lennart; Odnevall Wallinder, Inger; Karlsson, Hanna L; Elihn, Karine

    2016-10-01

    The use of refined toxicological methods is currently needed for characterizing the risks of airborne nanoparticles (NPs) to human health. To mimic pulmonary exposure, we have developed an air-liquid interface (ALI) exposure system for direct deposition of airborne NPs on to lung cell cultures. Compared to traditional submerged systems, this allows more realistic exposure conditions for characterizing toxicological effects induced by airborne NPs. The purpose of this study was to investigate how the deposition of silver NPs (AgNPs) is affected by different conditions of the ALI system. Additionally, the viability and metabolic activity of A549 cells was studied following AgNP exposure. Particle deposition increased markedly with increasing aerosol flow rate and electrostatic field strength. The highest amount of deposited particles (2.2 μg cm(-2) ) at cell-free conditions following 2 h exposure was observed for the highest flow rate (390 ml min(-1) ) and the strongest electrostatic field (±2 kV). This was estimated corresponding to deposition efficiency of 94%. Cell viability was not affected after 2 h exposure to clean air in the ALI system. Cells exposed to AgNPs (0.45 and 0.74 μg cm(-2) ) showed significantly (P < 0.05) reduced metabolic activities (64 and 46%, respectively). Our study shows that the ALI exposure system can be used for generating conditions that were more realistic for in vitro exposures, which enables improved mechanistic and toxicological studies of NPs in contact with human lung cells.Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd.

  5. Exposure of Mammalian Cells to Air-Pollutant Mixtures at the Air-Liquid Interface

    EPA Science Inventory

    It has been widely accepted that exposure of mammalian cells to air-pollutant mixtures at the air-liquid interface is a more realistic approach than exposing cell under submerged conditions. The VITROCELL systems, are commercially available systems for air-liquid interface expo...

  6. Usefulness of toxicological validation of VOCs catalytic degradation by air-liquid interface exposure system.

    PubMed

    Al Zallouha, Margueritta; Landkocz, Yann; Brunet, Julien; Cousin, Renaud; Genty, Eric; Courcot, Dominique; Siffert, Stéphane; Shirali, Pirouz; Billet, Sylvain

    2017-01-01

    Toluene is one of the most used Volatile Organic Compounds (VOCs) in the industry despite its major health impacts. Catalytic oxidation represents an efficient remediation technique in order to reduce its emission directly at the source, but it can release by-products. To complete the classical performance assessment using dedicated analytical chemistry methods, we propose to perform an untargeted toxicological validation on two efficient catalysts. Using biological system allows integrating synergy and antagonism in toxic effects of emitted VOCs and by-products, often described in case of multi-exposure condition. Catalysts Pd/α-Al2O3 and Pd/γ-Al2O3 developed for the oxidation of toluene were both coupled to a Vitrocell(®) Air-Liquid Interface (ALI) system, for exposure of human A549 lung cells during 1h to toluene or to catalysts exhaust before quantification of xenobiotics metabolizing enzymes. This study validated initially the Vitrocell(®) as an innovative, direct and dynamic model of ALI exposure in the assessment of the performances of new catalysts, showing the presence of chemically undetected by-products. The comparison of the two catalysts showed then that fewer organic compounds metabolizing genes were induced by Pd/γ-Al2O3 in comparison to Pd/α-Al2O3, suggesting that Pd/γ-Al2O3 is more efficient for toluene total oxidation from a toxicological point of view.

  7. Effects of Female Sex Hormones on Susceptibility to HSV-2 in Vaginal Cells Grown in Air-Liquid Interface

    PubMed Central

    Lee, Yung; Dizzell, Sara E.; Leung, Vivian; Nazli, Aisha; Zahoor, Muhammad A.; Fichorova, Raina N.; Kaushic, Charu

    2016-01-01

    The lower female reproductive tract (FRT) is comprised of the cervix and vagina, surfaces that are continuously exposed to a variety of commensal and pathogenic organisms. Sexually transmitted viruses, such as herpes simplex virus type 2 (HSV-2), have to traverse the mucosal epithelial lining of the FRT to establish infection. The majority of current culture systems that model the host-pathogen interactions in the mucosal epithelium have limitations in simulating physiological conditions as they employ a liquid-liquid interface (LLI), in which both apical and basolateral surfaces are submerged in growth medium. We designed the current study to simulate in vivo conditions by growing an immortalized vaginal epithelial cell line (Vk2/E6E7) in culture with an air-liquid interface (ALI) and examined the effects of female sex hormones on their growth, differentiation, and susceptibility to HSV-2 under these conditions, in comparison to LLI cultures. ALI conditions induced Vk2/E6E7 cells to grow into multi-layered cultures compared to the monolayers present in LLI conditions. Vk2 cells in ALI showed higher production of cytokeratin in the presence of estradiol (E2), compared to cells grown in progesterone (P4). Cells grown under ALI conditions were exposed to HSV-2-green fluorescent protein (GFP) and the highest infection and replication was observed in the presence of P4. Altogether, this study suggests that ALI cultures more closely simulate the in vivo conditions of the FRT compared to the conventional LLI cultures. Furthermore, under these conditions P4 was found to confer higher susceptibility to HSV-2 infection in vaginal cells. The vaginal ALI culture system offers a better alternative to study host-pathogen interactions. PMID:27589787

  8. Effects of Female Sex Hormones on Susceptibility to HSV-2 in Vaginal Cells Grown in Air-Liquid Interface.

    PubMed

    Lee, Yung; Dizzell, Sara E; Leung, Vivian; Nazli, Aisha; Zahoor, Muhammad A; Fichorova, Raina N; Kaushic, Charu

    2016-08-30

    The lower female reproductive tract (FRT) is comprised of the cervix and vagina, surfaces that are continuously exposed to a variety of commensal and pathogenic organisms. Sexually transmitted viruses, such as herpes simplex virus type 2 (HSV-2), have to traverse the mucosal epithelial lining of the FRT to establish infection. The majority of current culture systems that model the host-pathogen interactions in the mucosal epithelium have limitations in simulating physiological conditions as they employ a liquid-liquid interface (LLI), in which both apical and basolateral surfaces are submerged in growth medium. We designed the current study to simulate in vivo conditions by growing an immortalized vaginal epithelial cell line (Vk2/E6E7) in culture with an air-liquid interface (ALI) and examined the effects of female sex hormones on their growth, differentiation, and susceptibility to HSV-2 under these conditions, in comparison to LLI cultures. ALI conditions induced Vk2/E6E7 cells to grow into multi-layered cultures compared to the monolayers present in LLI conditions. Vk2 cells in ALI showed higher production of cytokeratin in the presence of estradiol (E2), compared to cells grown in progesterone (P4). Cells grown under ALI conditions were exposed to HSV-2-green fluorescent protein (GFP) and the highest infection and replication was observed in the presence of P4. Altogether, this study suggests that ALI cultures more closely simulate the in vivo conditions of the FRT compared to the conventional LLI cultures. Furthermore, under these conditions P4 was found to confer higher susceptibility to HSV-2 infection in vaginal cells. The vaginal ALI culture system offers a better alternative to study host-pathogen interactions.

  9. Cigarette smoke alters primary human bronchial epithelial cell differentiation at the air-liquid interface.

    PubMed

    Schamberger, Andrea C; Staab-Weijnitz, Claudia A; Mise-Racek, Nikica; Eickelberg, Oliver

    2015-02-02

    The differentiated human airway epithelium consists of different cell types forming a polarized and pseudostratified epithelium. This is dramatically altered in chronic obstructive pulmonary disease (COPD), characterized by basal and goblet cell hyperplasia, and squamous cell metaplasia. The effect of cigarette smoke on human bronchial epithelial cell (HBEC) differentiation remains to be elucidated. We analysed whether cigarette smoke extract (CSE) affected primary (p)HBEC differentiation and function. pHBEC were differentiated at the air-liquid interface (ALI) and differentiation was quantified after 7, 14, 21, or 28 days by assessing acetylated tubulin, CC10, or MUC5AC for ciliated, Clara, or goblet cells, respectively. Exposure of differentiating pHBEC to CSE impaired epithelial barrier formation, as assessed by resistance measurements (TEER). Importantly, CSE exposure significantly reduced the number of ciliated cells, while it increased the number of Clara and goblet cells. CSE-dependent cell number changes were reflected by a reduction of acetylated tubulin levels, an increased expression of the basal cell marker KRT14, and increased secretion of CC10, but not by changes in transcript levels of CC10, MUC5AC, or FOXJ1. Our data demonstrate that cigarette smoke specifically alters the cellular composition of the airway epithelium by affecting basal cell differentiation in a post-transcriptional manner.

  10. Cell deformation at the air-liquid interface induces Ca2+-dependent ATP release from lung epithelial cells.

    PubMed

    Ramsingh, Ronaldo; Grygorczyk, Alexandra; Solecki, Anna; Cherkaoui, Lalla Siham; Berthiaume, Yves; Grygorczyk, Ryszard

    2011-04-01

    Extracellular nucleotides regulate mucociliary clearance in the airways and surfactant secretion in alveoli. Their release is exquisitely mechanosensitive and may be induced by stretch as well as airflow shear stress acting on lung epithelia. We hypothesized that, in addition, tension forces at the air-liquid interface (ALI) may contribute to mechanosensitive ATP release in the lungs. Local depletion of airway surface liquid, mucins, and surfactants, which normally protect epithelial surfaces, facilitate such release and trigger compensatory mucin and fluid secretion processes. In this study, human bronchial epithelial 16HBE14o(-) and alveolar A549 cells were subjected to tension forces at the ALI by passing an air bubble over the cell monolayer in a flow-through chamber, or by air exposure while tilting the cell culture dish. Such stimulation induced significant ATP release not involving cell lysis, as verified by ethidium bromide staining. Confocal fluorescence microscopy disclosed reversible cell deformation in the monolayer part in contact with the ALI. Fura 2 fluorescence imaging revealed transient intracellular Ca(2+) elevation evoked by the ALI, which did not entail nonspecific Ca(2+) influx from the extracellular space. ATP release was reduced by ∼40 to ∼90% from cells loaded with the Ca(2+) chelator BAPTA-AM and was completely abolished by N-ethylmalemide (1 mM). These experiments demonstrate that in close proximity to the ALI, surface tension forces are transmitted directly on cells, causing their mechanical deformation and Ca(2+)-dependent exocytotic ATP release. Such a signaling mechanism may contribute to the detection of local deficiency of airway surface liquid and surfactants on the lung surface.

  11. Particle separation by a moving air-liquid interface in a microchannel.

    PubMed

    Wang, Fengkun; Chon, Chan Hee; Li, Dongqing

    2010-12-15

    Particle separation is an important topic in microfluidic field and has recently gained significant attention in sample preparations for biological and chemical studies. In this paper, a novel particle separation method was proposed. In this method, the particles were separated by the air-liquid interface in a microchannel. The motion of the air-liquid interface was controlled with a syringe pump. Depending on the air-liquid interface speed, the liquid film thickness and the viscous force on particles were changed and the particles were separated by sizes. We observed the separation of 1.01 μm particles from the larger particles when the air-liquid interface speed was less than 11 μm/s, and the separation of both 1.01 μm and 5.09 μm particles from the larger particles when the interface speed was between 11 μm/s and 120 μm/s. When the speed was higher than 120 μm/s, the drag force of the liquid flow generated by the advancing interface on particles was so strong that the flow removed all particles off from the bottom channel wall and there were no particles left behind the advancing interface.

  12. Determinative factors of competitive advantage between aerobic bacteria for niches at the air-liquid interface.

    PubMed

    Yamamoto, Kyosuke; Haruta, Shin; Kato, Souichiro; Ishii, Masaharu; Igarashi, Yasuo

    2010-01-01

    We focused on bacterial interspecies relationships at the air-liquid interface where the formation of pellicles by aerobes was observed. Although an obligate aerobe (Brevibacillus sp. M1-5) was initially dominant in the pellicle population, a facultative aerobe (Pseudoxanthomonas sp. M1-3) emerged and the viability of M1-5 rapidly decreased due to severe competition for oxygen. Supplementation of the medium with carbohydrates allowed the two species to coexist at the air-liquid interface. These results indicate that the population dynamics within pellicles are primarily governed by oxygen utilization which was affected by a combination of carbon sources.

  13. Self-assembly of a surfactin nanolayer at solid-liquid and air-liquid interfaces.

    PubMed

    Onaizi, Sagheer A; Nasser, M S; Al-Lagtah, Nasir M A

    2016-05-01

    Surfactin, a sustainable and environmentally friendly surface active agent, is used as a model to study the adsorption of biosurfactants at hydrophobic and hydrophilic solid-liquid interfaces as well as the air-liquid interface. Surfactin adsorption was monitored as a function of time and concentration using surface plasmon resonance (SPR) technique in the case of the solid-liquid interfaces or the drop shape analysis (DSA) technique in the case of the air-liquid interface. The results obtained in this study showed that surfactin adsorption at the "hard" hydrophobic (functionalized with octadecanethiol) solid-liquid and the "soft" air-liquid interface were 1.12 ± 0.01 mg m(-2) (area per molecule of 157 ± 2 Å(2)) and 1.11 ± 0.05 mg m(-2) (area per molecule of 159 ± 7 Å(2)), respectively, demonstrating the negligible effect of the interface "hardness" on surfactin adsorption. The adsorption of surfactin at the hydrophilic (functionalized with β-mercaptoethanol) solid-liquid interface was about threefold lower than its adsorption at the hydrophobic-liquid interfaces, revealing the importance of hydrophobic interaction in surfactin adsorption process. The affinity constant of surfactin for the investigated interfaces follows the following order: air > octadecanethiol > β-mercaptoethanol. Biosurfactants, such as surfactin, are expected to replace the conventional fossil-based surfactants in several applications, and therefore the current study is a contribution towards the fundamental understanding of biosurfactant behavior, on a molecular level, at hydrophobic and hydrophilic solid-liquid interfaces in addition to the air-liquid interface. Such understanding might aid further optimization of the utilization of surfactin in a number of industrial applications such as enhanced oil recovery, bioremediation, and detergency.

  14. A Method To Measure Protein Unfolding at an Air-Liquid Interface.

    PubMed

    Leiske, Danielle L; Shieh, Ian C; Tse, Martha Lovato

    2016-10-04

    Proteins are surface-active molecules that have a propensity to adsorb to hydrophobic interfaces, such as the air-liquid interface. Surface flow can increase aggregation of adsorbed proteins, which may be an undesirable consequence depending on the application. As changes in protein conformation upon adsorption are thought to induce aggregation, the ability to measure the folded state of proteins at interfaces is of particular interest. However, few techniques currently exist to measure protein conformation at interfaces. Here we describe a technique capable of measuring the hydrophobicity, and therefore the conformation and folded state, of proteins at air-liquid interfaces by exploiting the environmentally sensitive fluorophore Nile red. Two monoclonal antibodies (mAbs) with high (mAb1) and low (mAb2) surface activity were used to highlight the technique. Both mAbs showed low background fluorescence of Nile red in the liquid subphase and at a glass-liquid interface. In contrast, at the air-liquid interface Nile red fluorescence for mAb1 increased immediately after protein adsorption, whereas the Nile red fluorescence of the mAb2 film evolved more slowly in time even though the adsorbed quantity of protein remained constant. The results demonstrate that hydrophobicity upon mAb adsorption to the air-liquid interface evolves in a time-dependent manner. Interfacial hydrophobicity may be indicative of protein conformation or folded state, where rapid unfolding of mAb1 upon adsorption would be consistent with increased protein aggregation compared to mAb2. The ability to measure protein hydrophobicity at interfaces using Nile red, combined with small sample requirements and minimal sample preparation, fills a gap in existing interfacial techniques.

  15. Aerosol generation and characterization of multi-walled carbon nanotubes exposed to cells cultured at the air-liquid interface.

    PubMed

    Polk, William W; Sharma, Monita; Sayes, Christie M; Hotchkiss, Jon A; Clippinger, Amy J

    2016-04-23

    Aerosol generation and characterization are critical components in the assessment of the inhalation hazards of engineered nanomaterials (NMs). An extensive review was conducted on aerosol generation and exposure apparatus as part of an international expert workshop convened to discuss the design of an in vitro testing strategy to assess pulmonary toxicity following exposure to aerosolized particles. More specifically, this workshop focused on the design of an in vitro method to predict the development of pulmonary fibrosis in humans following exposure to multi-walled carbon nanotubes (MWCNTs). Aerosol generators, for dry or liquid particle suspension aerosolization, and exposure chambers, including both commercially available systems and those developed by independent researchers, were evaluated. Additionally, characterization methods that can be used and the time points at which characterization can be conducted in order to interpret in vitro exposure results were assessed. Summarized below is the information presented and discussed regarding the relevance of various aerosol generation and characterization techniques specific to aerosolized MWCNTs exposed to cells cultured at the air-liquid interface (ALI). The generation of MWCNT aerosols relevant to human exposures and their characterization throughout exposure in an ALI system is critical for extrapolation of in vitro results to toxicological outcomes in humans.

  16. Swimming of a model ciliate near an air-liquid interface

    NASA Astrophysics Data System (ADS)

    Wang, S.; Ardekani, A. M.

    2013-06-01

    In this work, the role of the hydrodynamic forces on a swimming microorganism near an air-liquid interface is studied. The lubrication theory is utilized to analyze hydrodynamic effects within the narrow gap between a flat interface and a small swimmer. By using an archetypal low-Reynolds-number swimming model called “squirmer,” we find that the magnitude of the vertical swimming velocity is on the order of O(ɛlnɛ), where ɛ is the ratio of the gap width to the swimmer's body size. The reduced swimming velocity near an interface can explain experimental observations of the aggregation of microorganisms near a liquid interface.

  17. Swimming of a model ciliate near an air-liquid interface.

    PubMed

    Wang, S; Ardekani, A M

    2013-06-01

    In this work, the role of the hydrodynamic forces on a swimming microorganism near an air-liquid interface is studied. The lubrication theory is utilized to analyze hydrodynamic effects within the narrow gap between a flat interface and a small swimmer. By using an archetypal low-Reynolds-number swimming model called "squirmer," we find that the magnitude of the vertical swimming velocity is on the order of O(εlnε), where ε is the ratio of the gap width to the swimmer's body size. The reduced swimming velocity near an interface can explain experimental observations of the aggregation of microorganisms near a liquid interface.

  18. Aerosolized ZnO nanoparticles induce toxicity in alveolar type II epithelial cells at the air-liquid interface

    SciTech Connect

    Xie, Yumei; Williams, Nolann G.; Tolic, Ana; Chrisler, William B.; Teeguarden, Justin G.; Maddux, Bettye L.; Pounds, Joel G.; Laskin, Alexander; Orr, Galya

    2012-01-20

    The majority of in vitro studies characterizing the impact of engineered nanoparticles (NPs) on cells that line the respiratory tract were conducted in cells exposed to NPs in suspension. This approach introduces processes that are unlikely to occur during inhaled NP exposures in vivo, such as the shedding of toxic doses of dissolved ions. ZnO NPs are used extensively and pose significant sources for human exposure. Exposures to airborne ZnO NPs can induce adverse effects, but the relevance of the dissolved Zn2+ to the observed effects in vivo is still unclear. Our goal was to mimic in vivo exposures to airborne NPs and decipher the contribution of the intact NP from the contribution of the dissolved ions to airborne ZnO NP toxicity. We established the exposure of alveolar type II epithelial cells to aerosolized NPs at the air-liquid interface (ALI), and compared the impact of aerosolized ZnO NPs and NPs in suspension at the same cellular doses, measured as the number of particles per cell. By evaluating membrane integrity and cell viability 6 and 24 hours post exposure we found that aerosolized NPs induced toxicity at the ALI at doses that were in the same order of magnitude as doses required to induce toxicity in submersed cultures. In addition, distinct patterns of oxidative stress were observed in the two exposure systems. These observations unravel the ability of airborne ZnO NPs to induce toxicity without the contribution of dissolved Zn2+ and suggest distinct mechanisms at the ALI and in submersed cultures.

  19. Air-liquid interface cultures enhance the oxygen supply and trigger the structural and functional differentiation of intestinal porcine epithelial cells (IPEC).

    PubMed

    Nossol, Constanze; Diesing, A-K; Walk, N; Faber-Zuschratter, H; Hartig, R; Post, A; Kluess, J; Rothkötter, H-J; Kahlert, S

    2011-07-01

    The specific function of the epithelium as critical barrier between the intestinal lumen and the organism's internal microenvironment is reflected by permanent maintenance of intercellular junctions and cellular polarity. The intestinal epithelial cells are responsible for absorption of nutritional components, facing mechanical stress and a changing oxygen supplementation via blood stream. Oxygen itself can regulate the barrier and the absorptive function of the epithelium. Therefore, we compared the dish cell culture, the transwell-like membrane culture and the oxygen enriched air-liquid interface (ALI) culture. We demonstrated strong influence of the different culture conditions on morphology and function of intestinal porcine epithelial cell lines in vitro. ALI culture resulted in a significant increase in cell number, epithelial cell layer thickness and expression as well as apical localisation of the microvilli-associated protein villin. Remarkable similarities regarding the morphological parameters were observed between ALI cultures and intestinal epithelial cells in vivo. Furthermore, the functional analysis of protein uptake and degradation by the epithelial cells demonstrated the necessity of sufficient oxygen supply as achieved in ALI cultures. Our study is the first report providing marked evidence that optimised oxygen supply using ALI cultures directly affects the morphological differentiation and functional properties of intestinal epithelial cells in vitro.

  20. Quantitative assessment of radiation force effect at the dielectric air-liquid interface

    PubMed Central

    Capeloto, Otávio Augusto; Zanuto, Vitor Santaella; Malacarne, Luis Carlos; Baesso, Mauro Luciano; Lukasievicz, Gustavo Vinicius Bassi; Bialkowski, Stephen Edward; Astrath, Nelson Guilherme Castelli

    2016-01-01

    We induce nanometer-scale surface deformation by exploiting momentum conservation of the interaction between laser light and dielectric liquids. The effect of radiation force at the air-liquid interface is quantitatively assessed for fluids with different density, viscosity and surface tension. The imparted pressure on the liquids by continuous or pulsed laser light excitation is fully described by the Helmholtz electromagnetic force density. PMID:26856622

  1. UV-Vis reflection spectroscopy under variable angle incidence at the air-liquid interface.

    PubMed

    Roldán-Carmona, Cristina; Rubia-Payá, Carlos; Pérez-Morales, Marta; Martín-Romero, María T; Giner-Casares, Juan J; Camacho, Luis

    2014-03-07

    The UV-Vis reflection spectroscopy (UV-Vis-RS) in situ at the air-liquid interface provides information about tilt and aggregation of chromophores in Langmuir monolayers. This information is particularly important given in most cases the chromophore is located at the polar region of the Langmuir monolayer. This region of the Langmuir monolayers has been hardly accessible by other experimental techniques. In spite of its enormous potential, the application of UV-Vis-RS has been limited mainly to reflection measurements under light normal incidence or at lower incidence angles than the Brewster angle. Remarkably, this technique is quite sensitive to the tilt of the chromophores at values of incidence angles close to or larger than the Brewster angle. Therefore, a novel method to obtain the order parameter of the chromophores at the air-liquid interface by using s- and p-polarized radiation at different incidence angles is proposed. This method allowed for the first time the experimental observation of the two components with different polarization properties of a single UV-Vis band at the air-liquid interface. The method of UV-Vis spectroscopy under variable angle incidence is presented as a new tool for obtaining rich detailed information on Langmuir monolayers.

  2. Biofilm formation at the solid-liquid and air-liquid interfaces by Acinetobacter species

    PubMed Central

    2011-01-01

    Background The members of the genus Acinetobacter are Gram-negative cocobacilli that are frequently found in the environment but also in the hospital setting where they have been associated with outbreaks of nosocomial infections. Among them, Acinetobacter baumannii has emerged as the most common pathogenic species involved in hospital-acquired infections. One reason for this emergence may be its persistence in the hospital wards, in particular in the intensive care unit; this persistence could be partially explained by the capacity of these microorganisms to form biofilm. Therefore, our main objective was to study the prevalence of the two main types of biofilm formed by the most relevant Acinetobacter species, comparing biofilm formation between the different species. Findings Biofilm formation at the air-liquid and solid-liquid interfaces was investigated in different Acinetobacter spp. and it appeared to be generally more important at 25°C than at 37°C. The biofilm formation at the solid-liquid interface by the members of the ACB-complex was at least 3 times higher than the other species (80-91% versus 5-24%). In addition, only the isolates belonging to this complex were able to form biofilm at the air-liquid interface; between 9% and 36% of the tested isolates formed this type of pellicle. Finally, within the ACB-complex, the biofilm formed at the air-liquid interface was almost 4 times higher for A. baumannii and Acinetobacter G13TU than for Acinetobacter G3 (36%, 27% & 9% respectively). Conclusions Overall, this study has shown the capacity of the Acinetobacter spp to form two different types of biofilm: solid-liquid and air-liquid interfaces. This ability was generally higher at 25°C which might contribute to their persistence in the inanimate hospital environment. Our work has also demonstrated for the first time the ability of the members of the ACB-complex to form biofilm at the air-liquid interface, a feature that was not observed in other

  3. Computational study of ion distributions at the air/liquid methanol interface

    SciTech Connect

    Sun, Xiuquan; Wick, Collin D.; Dang, Liem X.

    2011-06-16

    Molecular dynamic simulations with polarizable potentials were performed to systematically investigate the distribution of NaCl, NaBr, NaI, and SrCl2 at the air/liquid methanol interface. The density profiles indicated that there is no substantial enhancement of anions at the interface for the NaX systems in contrast to what was observed at the air/aqueous interface. The surfactant-like shape of the larger more polarizable halide anions is compensated by the surfactant nature of methanol itself. As a result, methanol hydroxy groups strongly interacted with one side of polarizable anions, in which their induced dipole points, and methanol methyl groups were more likely to be found near the positive pole of anion induced dipoles. Furthermore, salts were found to disrupt the surface structure of methanol, reducing the observed enhancement of methyl groups at the outer edge of the air/liquid methanol interface. With the additional of salts to methanol, the computed surface potentials increased, which is in contrast to what is observed in corresponding aqueous systems, where the surface potential decreases with the addition of salts. Both of these trends have been indirectly observed with experiments. This was found to be due to the propensity of anions for the air/water interface that is not present at the air/liquid methanol interface. This work was supported by the US Department of Energy Basic Energy Sciences' Chemical Sciences, Geosciences & Biosciences Division. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  4. The production of drops by the bursting of a bubble at an air liquid interface

    NASA Technical Reports Server (NTRS)

    Darrozes, J. S.; Ligneul, P.

    1982-01-01

    The fundamental mechanism arising during the bursting of a bubble at an air-liquid interface is described. A single bubble was followed from an arbitrary depth in the liquid, up to the creation and motion of the film and jet drops. Several phenomena were involved and their relative order of magnitude was compared in order to point out the dimensionless parameters which govern each step of the motion. High-speed cinematography is employed. The characteristic bubble radius which separates the creation of jet drops from cap bursting without jet drops is expressed mathematically. The corresponding numerical value for water is 3 mm and agrees with experimental observations.

  5. The DNA Adsorption by the Charged Cholesterol Monolayer at the Air-liquid Interface

    NASA Astrophysics Data System (ADS)

    Lin, Tsang-Lang; Hu, Yuan; Wu, Jui-Ching; Yang, Chun-Pang; Jeng, U.-Ser; Shih, M.-C.

    2004-04-01

    The adsorption of DNA by the 3-,-[N-(N',N'-dimethyl amino ethane) carbamoyl] cholesterol (DC-Chol) monolayer at the air-liquid interface was studied by using the Langmuir-Blodgett film balance. With the presence of 1 μ M DNA in the subphase, the surface pressure increases right at the beginning of the compression. The liquid expanded phase of the DC-Chol disappears due to the adsorption of DNA. The AFM image of the prepared DC-Chol/DNA film has tree-branch-like fractal structure with a height of 2 nm that correspond to the diameter of DNA.

  6. Detachment force of particles from air-liquid interfaces of films and bubbles.

    PubMed

    Ally, Javed; Kappl, Michael; Butt, Hans-Jürgen; Amirfazli, A

    2010-12-07

    The detachment force required to pull a microparticle from an air-liquid interface is measured using atomic force microscopy (AFM) and the colloidal probe technique. Water, solutions of sodium dodecyl sulfate (SDS), and silicone oils are tested in order to study the effects of surface tension and viscosity. Two different liquid geometries are considered: the air-liquid interface of a bubble and a liquid film on a solid substrate. It was shown that detaching particles from liquid films is fundamentally different than from bubbles or drops due to the restricted flow of the liquid phase. Additional force is required to detach a particle from a film, and the maximum force during detachment is not necessarily at the position where the particle breaks away from the interface (as seen in bubble or drop systems). This is due to the dynamics of meniscus formation and viscous effects, which must be considered if the liquid is constrained in a film. The magnitude of these effects is related to the liquid viscosity, film thickness, and detachment speed.

  7. Solid mesostructured polymer-surfactant films at the air-liquid interface.

    PubMed

    Pegg, Jonathan C; Eastoe, Julian

    2015-08-01

    Pioneering work by Edler et al. has spawned a new sub-set of mesostructured materials. These are solid, self-supporting films comprising surfactant micelles encased within polymer hydrogel; composite polymer-surfactant films can be grown spontaneously at the air-liquid interface and have defined and controllable mesostructures. Addition of siliconalkoxide to polymer-surfactant mixtures allows for the growth of mesostructured hybrid polymer-surfactant silica films that retain film geometry after calcinations and exhibit superior mechanical properties to typically brittle inorganic films. Growing films at the air-liquid interface provides a rapid and simple means to prepare ordered solid inorganic films, and to date the only method for generating mesostructured films thick enough (up to several hundred microns) to be removed from the interface. Applications of these films could range from catalysis to encapsulation of hydrophobic species and drug delivery. Film properties and mesostructures are sensitive to surfactant structure, polymer properties and polymer-surfactant phase behaviour: herein it will be shown how film mesostructure can be tailored by directing these parameters, and some interesting analogies will be drawn with more familiar mesostructured silica materials.

  8. A novel method for pulmonary research: assessment of bioenergetic function at the air-liquid interface.

    PubMed

    Xu, Weiling; Janocha, Allison J; Leahy, Rachel A; Klatte, Ryan; Dudzinski, Dave; Mavrakis, Lori A; Comhair, Suzy A A; Lauer, Mark E; Cotton, Calvin U; Erzurum, Serpil C

    2014-01-01

    Air-liquid interface cell culture is an organotypic model for study of differentiated functional airway epithelium in vitro. Dysregulation of cellular energy metabolism and mitochondrial function have been suggested to contribute to airway diseases. However, there is currently no established method to determine oxygen consumption and glycolysis in airway epithelium in air-liquid interface. In order to study metabolism in differentiated airway epithelial cells, we engineered an insert for the Seahorse XF24 Analyzer that enabled the measure of respiration by oxygen consumption rate (OCR) and glycolysis by extracellular acidification rate (ECAR). Oxidative metabolism and glycolysis in airway epithelial cells cultured on the inserts were successfully measured. The inserts did not affect the measures of OCR or ECAR. Cells under media with apical and basolateral feeding had less oxidative metabolism as compared to cells on the inserts at air-interface with basolateral feeding. The design of inserts that can be used in the measure of bioenergetics in small numbers of cells in an organotypic state may be useful for evaluation of new drugs and metabolic mechanisms that underlie airway diseases.

  9. UV-Vis Reflection-Absorption Spectroscopy at air-liquid interfaces.

    PubMed

    Rubia-Payá, Carlos; de Miguel, Gustavo; Martín-Romero, María T; Giner-Casares, Juan J; Camacho, Luis

    2015-11-01

    UV-Visible Reflection-Absorption Spectroscopy (UVRAS) technique is reviewed with a general perspective on fundamental and applications. UVRAS is formally identical to IR Reflection-Absorption Spectroscopy (IRRAS), and therefore, the methodology developed for this IR technique can be applied in the UV-visible region. UVRAS can be applied to air-solid, air-liquid or liquid-liquid interfaces. This review focuses on the use of UVRAS for studying Langmuir monolayers. We introduce the theoretical framework for a successful understanding of the UVRAS data, and we illustrate the usage of this data treatment to a previous study from our group comprising an amphiphilic porphyrin. For ultrathin films with a thickness of few nm, UVRAS produces positive or negative bands when p-polarized radiation is used, depending on the incidence angle and the orientation of dipole absorption. UVRAS technique provides highly valuable information on tilt of chromophores at the air-liquid interface, and moreover allows the determination of optical parameters. We propose UVRAS as a powerful technique to investigate the in situ optical properties of Langmuir monolayers.

  10. Use of a feline respiratory epithelial cell culture system grown at the air-liquid interface to characterize the innate immune response following feline herpesvirus 1 infection.

    PubMed

    Nelli, Rahul K; Maes, Roger; Kiupel, Matti; Hussey, Gisela Soboll

    2016-03-02

    Infection with feline herpesvirus-1 (FHV-1) accounts for 50% of viral upper respiratory diseases in domestic cats and is a significant cause of ocular diseases. Despite the clinical significance and high prevalence of FHV-1 infection, currently available vaccines cannot completely protect cats from infection and lifelong latency. FHV-1 infects via the mucous membranes and replicates in respiratory epithelial cells, but very little is known about the early innate immunity at this site. To address questions about immunity to FHV-1, feline respiratory epithelial cells cultured at air-liquid interface (ALI-FRECs) were established by collecting respiratory tracts from 6 healthy cats after euthanasia. Cells were isolated, cultured and characterized histologically and immunologically before infection with FHV-1. The expression of Toll-like receptors (TLRs), cytokine and chemokine responses were measured by real time PCR. ALI-FRECs morphologically resembled the natural airways of cats with multilayered columnar epithelial cells and cilia. Immunological properties of the natural airways were maintained in ALI-FRECs, as evidenced by the expression of TLRs, cytokines, chemokines, interferons, beta-defensins, and other regulatory genes. Furthermore, ALI-FRECs were able to support infection and replication of FHV-1, as well as modulate transcriptional regulation of various immune genes in response to infection. IL-1β and TNFα were increased in ALI-FRECs by 24hpi, whereas expression levels of IFN-α and TLR9 were not increased until 36hpi. In contrast, TLR3, GM-CSF and TGF-1β expression was down-regulated at 36hpi. The data presented show the development of a system ideal for investigating the molecular pathogenesis and immunity of FHV-1 or other respiratory pathogens.

  11. Culture of Primary Ciliary Dyskinesia Epithelial Cells at Air-Liquid Interface Can Alter Ciliary Phenotype but Remains a Robust and Informative Diagnostic Aid

    PubMed Central

    Coles, Janice L.; Williams, Gwyneth; Rutman, Andrew; Goggin, Patricia M.; Adam, Elizabeth C.; Page, Anthony; Evans, Hazel J.; Lackie, Peter M.; O’Callaghan, Christopher; Lucas, Jane S.

    2014-01-01

    Background The diagnosis of primary ciliary dyskinesia (PCD) requires the analysis of ciliary function and ultrastructure. Diagnosis can be complicated by secondary effects on cilia such as damage during sampling, local inflammation or recent infection. To differentiate primary from secondary abnormalities, re-analysis of cilia following culture and re-differentiation of epithelial cells at an air-liquid interface (ALI) aids the diagnosis of PCD. However changes in ciliary beat pattern of cilia following epithelial cell culture has previously been described, which has brought the robustness of this method into question. This is the first systematic study to evaluate ALI culture as an aid to diagnosis of PCD in the light of these concerns. Methods We retrospectively studied changes associated with ALI-culture in 158 subjects referred for diagnostic testing at two PCD centres. Ciliated nasal epithelium (PCD n = 54; non-PCD n = 111) was analysed by high-speed digital video microscopy and transmission electron microscopy before and after culture. Results Ciliary function was abnormal before and after culture in all subjects with PCD; 21 PCD subjects had a combination of static and uncoordinated twitching cilia, which became completely static following culture, a further 9 demonstrated a decreased ciliary beat frequency after culture. In subjects without PCD, secondary ciliary dyskinesia was reduced. Conclusions The change to ciliary phenotype in PCD samples following cell culture does not affect the diagnosis, and in certain cases can assist the ability to identify PCD cilia. PMID:24586956

  12. Newborn pig trachea cell line cultured in air-liquid interface conditions allows a partial in vitro representation of the porcine upper airway tissue

    PubMed Central

    2014-01-01

    Background The domestic pig is an excellent animal model to study human microbial diseases due to its similarity to humans in terms of anatomy, physiology, and genetics. We assessed the suitability of an in vitro air-liquid interface (ALI) culture system for newborn pig trachea (NPTr) cells as a practical tool for analyzing the immune response of respiratory epithelial cells to aggressors. This cell line offers a wide microbial susceptibility spectrum to both viruses and bacteria. The purpose of our study was to evaluate and characterize diverse aspects of cell differentiation using different culture media. After the NPTr cells reached confluence, the apical medium was removed and the cells were fed by medium from the basal side. Results We assessed the cellular layer’s capacity to polarize and differentiate in ALI conditions. Using immunofluorescence and electronic microscopy we evaluated the presence of goblet and ciliated cells, the epithelial junction organization, and the transepithelial electrical resistance. We found that the cellular layer develops a variable density of mucus producing cells and acquires a transepithelial resistance. We also identified increased development of cellular junctions over the culture period. Finally, we observed variable expression of transcripts associated to proteins such as keratin 8, mucins (MUC1, MUC2, and MUC4), occludin, and villin 1. Conclusions The culture of NPTr cells in ALI conditions allows a partial in vitro representation of porcine upper airway tissue that could be used to investigate some aspects of host/respiratory pathogen interactions. PMID:24885012

  13. Detection of the cytotoxicity of water-insoluble fraction of cigarette smoke by direct exposure to cultured cells at an air-liquid interface.

    PubMed

    Nara, Hidenori; Fukano, Yasuo; Nishino, Tomoki; Aufderheide, Michaela

    2013-07-01

    For the biological evaluation of cigarette smoke in vitro, the particulate phase (PP) and the gas vapor phase (GVP) of mainstream smoke have usually been collected individually and exposed to biological material such as cultured cells. Using this traditional method, the GVP is collected by bubbling in an aqueous solution such as phosphate-buffered saline (PBS). In such a way the water-insoluble GVP fraction is excluded from the GVP, meaning that the toxic potential of the water-insoluble GVP fraction has hardly been investigated so far. In our experiments we used a direct exposure method to expose cells at the air-liquid interface (ALI) to the water-insoluble GVP fraction for demonstrating its toxicological/biological activity. In order to isolate the water-insoluble GVP fraction from mainstream smoke, the GVP was passed through 6 impingers connected in series with PBS. After direct exposure of Chinese hamster ovary cells (CHO-K1) with the water-insoluble GVP fraction in the CULTEX(®) system its cytotoxicity was assayed by using the neutral red uptake assay. The water-insoluble GVP fraction was proven to be less cytotoxic than the water-soluble GVP fraction, but showed a significant effect in a dose-dependent manner. The results of this study showed that the direct exposure of cultivated cells at the air-liquid interface offers the possibility to analyze the biological and toxicological activities of all fractions of cigarette smoke including the water-insoluble GVP fraction.

  14. In vitro toxicity testing of cigarette smoke based on the air-liquid interface exposure: A review.

    PubMed

    Li, Xiang

    2016-10-01

    Cigarette smoke is a complex aerosol comprising particulate phase and gaseous vapour phase. The air-liquid interface exposure provides a possible technical means to implement whole smoke exposure for the assessment of tobacco products. In this review, the research progress in the in vitro toxicity testing of cigarette smoke based on the air-liquid interface exposure is summarized. The contents presented involve mainly cytotoxicity, genotoxicity, oxidative stress, inflammation, systems toxicology, 3D culture and cigarette smoke dosimetry related to cigarette smoke, as well as the assessment of electronic cigarette aerosol. Prospect of the application of the air-liquid interface exposure method in assessing the biological effects of tobacco smoke is discussed.

  15. Analysis of Bacterial Detachment from Substratum Surfaces by the Passage of Air-Liquid Interfaces

    PubMed Central

    Gómez-Suárez, Cristina; Busscher, Henk J.; van der Mei, Henny C.

    2001-01-01

    A theoretical analysis of the detachment of bacteria adhering to substratum surfaces upon the passage of an air-liquid interface is given, together with experimental results for bacterial detachment in the absence and presence of a conditioning film on different substratum surfaces. Bacteria (Streptococcus sobrinus HG1025, Streptococcus oralis J22, Actinomyces naeslundii T14V-J1, Bacteroides fragilis 793E, and Pseudomonas aeruginosa 974K) were first allowed to adhere to hydrophilic glass and hydrophobic dimethyldichlorosilane (DDS)-coated glass in a parallel-plate flow chamber until a density of 4 × 106 cells cm−2 was reached. For S. sobrinus HG1025, S. oralis J22, and A. naeslundii T14V-J1, the conditioning film consisted of adsorbed salivary components, while for B. fragilis 793E and P. aeruginosa 974K, the film consisted of adsorbed human plasma components. Subsequently, air bubbles were passed through the flow chamber and the bacterial detachment percentages were measured. For some experimental conditions, like with P. aeruginosa 974K adhering to DDS-coated glass and an air bubble moving at high velocity (i.e., 13.6 mm s−1), no bacteria detached upon passage of an air-liquid interface, while for others, detachment percentages between 80 and 90% were observed. The detachment percentage increased when the velocity of the passing air bubble decreased, regardless of the bacterial strain and substratum surface hydrophobicity involved. However, the variation in percentages of detachment by a passing air bubble depended greatly upon the strain and substratum surface involved. At low air bubble velocities the hydrophobicity of the substratum had no influence on the detachment, but at high air bubble velocities all bacterial strains were more efficiently detached from hydrophilic glass substrata. Furthermore, the presence of a conditioning film could either inhibit or stimulate detachment. The shape of the bacterial cell played a major role in detachment at high

  16. Neutron reflectivity studies on the DNA adsorption on lipid monolayers at the air liquid interface

    NASA Astrophysics Data System (ADS)

    Wu, Jui-Ching; Lin, Tsang-Lang; Jeng, U.-Ser; Torikai, Naoya

    2006-11-01

    In situ neutron reflectivity was used to study the DC-Chol and TC-Chol monolayers at the air-liquid interface in the presence and absence of DNA in the subphase. It was found that the DC-Chol is more effective in adsorbing the DNA than the TC-Chol. It was also found that a compact DNA layer formed beneath the DC-Chol monolayer with a DNA gap spacing around 20 Å and a less compact DNA layer adsorbed to the TC-Chol monolayer with a DNA spacing around 60 Å, as estimated from the determined neutron scattering length density. From the determined neutron scattering length density profiles, the adsorbed DNA somewhat penetrates into the head group region of the charged lipids.

  17. Lamellar Bodies Form Solid Three-dimensional Films at the Respiratory Air-Liquid Interface*

    PubMed Central

    Ravasio, Andrea; Olmeda, Bárbara; Bertocchi, Cristina; Haller, Thomas; Pérez-Gil, Jesús

    2010-01-01

    Pulmonary surfactant is essential for lung function. It is assembled, stored and secreted as particulate entities (lamellar body-like particles; LBPs). LBPs disintegrate when they contact an air-liquid interface, leading to an instantaneous spreading of material and a decline in surface tension. Here, we demonstrate that the film formed by the adsorbed material spontaneously segregate into distinct ordered and disordered lipid phase regions under unprecedented near-physiological conditions and, unlike natural surfactant purified from bronchoalveolar lavages, dynamically reorganized into highly viscous multilayer domains with complex three-dimensional topographies. Multilayer domains, in coexistence with liquid phases, showed a progressive stiffening and finally solidification, probably driven by a self-driven disassembly of LBPs from a sub-surface compartment. We conclude that surface film formation from LBPs is a highly dynamic and complex process, leading to a more elaborated scenario than that observed and predicted by models using reconstituted, lavaged, or fractionated preparations. PMID:20558742

  18. Growth of human bronchial epithelial cells at an air-liquid interface alters the response to particle exposure

    EPA Science Inventory

    Abstract: We tested the hypothesis that relative to submerged cells, airway epithelial cells grown at an air-liquid interface would have an altered response to particle exposure. RNA for IL-8, IL-6, heme oxygenase 1 and cyclooxygenase 2 increased following exposure of submer...

  19. A dose-controlled system for air-liquid interface cell exposure and application to zinc oxide nanoparticles

    PubMed Central

    2009-01-01

    Background Engineered nanoparticles are becoming increasingly ubiquitous and their toxicological effects on human health, as well as on the ecosystem, have become a concern. Since initial contact with nanoparticles occurs at the epithelium in the lungs (or skin, or eyes), in vitro cell studies with nanoparticles require dose-controlled systems for delivery of nanoparticles to epithelial cells cultured at the air-liquid interface. Results A novel air-liquid interface cell exposure system (ALICE) for nanoparticles in liquids is presented and validated. The ALICE generates a dense cloud of droplets with a vibrating membrane nebulizer and utilizes combined cloud settling and single particle sedimentation for fast (~10 min; entire exposure), repeatable (<12%), low-stress and efficient delivery of nanoparticles, or dissolved substances, to cells cultured at the air-liquid interface. Validation with various types of nanoparticles (Au, ZnO and carbon black nanoparticles) and solutes (such as NaCl) showed that the ALICE provided spatially uniform deposition (<1.6% variability) and had no adverse effect on the viability of a widely used alveolar human epithelial-like cell line (A549). The cell deposited dose can be controlled with a quartz crystal microbalance (QCM) over a dynamic range of at least 0.02-200 μg/cm2. The cell-specific deposition efficiency is currently limited to 0.072 (7.2% for two commercially available 6-er transwell plates), but a deposition efficiency of up to 0.57 (57%) is possible for better cell coverage of the exposure chamber. Dose-response measurements with ZnO nanoparticles (0.3-8.5 μg/cm2) showed significant differences in mRNA expression of pro-inflammatory (IL-8) and oxidative stress (HO-1) markers when comparing submerged and air-liquid interface exposures. Both exposure methods showed no cellular response below 1 μg/cm2 ZnO, which indicates that ZnO nanoparticles are not toxic at occupationally allowed exposure levels. Conclusion The ALICE

  20. Toxicity of copper oxide nanoparticles in lung epithelial cells exposed at the air-liquid interface compared with in vivo assessment

    PubMed Central

    Jing, Xuefang; Park, Jae Hong; Peters, Thomas M.; Thorne, Peter S.

    2015-01-01

    The toxicity of spark-generated copper oxide nanoparticles (CuONPs) was evaluated in human bronchial epithelial cells (HBEC) and lung adenocarcinoma cells (A549 cells) using an in vitro air-liquid interface (ALI) exposure system. Dose-response results were compared to in vivo inhalation and instillation studies of CuONP. Cells were exposed to particle-free clean air (controls) or spark-generated CuONPs. The number median diameter, geometric standard deviation and total number concentration of CuONPs were 9.2 nm, 1.48 and 2.27×107 particles/cm3, respectively. Outcome measures included cell viability, cytotoxicity, oxidative stress and proinflammatory chemokine production. Exposure to clean air (2 or 4 hr) did not induce toxicity in HBEC or A549 cells. Compared with controls, CuONP exposures significantly reduced cell viability, increased lactate dehydrogenase (LDH) release and elevated levels of reactive oxygen species (ROS) and IL-8 in a dose-dependent manner. A549 cells were significantly more susceptible to CuONP effects than HBEC. Antioxidant treatment reduced CuONP-induced cytotoxicity. When dose was expressed per area of exposed epithelium there was good agreement of toxicity measures with murine in vivo studies. This demonstrates that in vitro ALI studies can provide meaningful data on nanotoxicity of metal oxides. PMID:25575782

  1. Evaluation of an air-liquid interface cell culture model for studies on the inflammatory and cytotoxic responses to tobacco smoke aerosols.

    PubMed

    Azzopardi, David; Haswell, Linsey E; Foss-Smith, Geoff; Hewitt, Katherine; Asquith, Nathan; Corke, Sarah; Phillips, Gary

    2015-10-01

    In vitro toxicological studies for tobacco product assessment have traditionally been undertaken using the particulate phase of tobacco smoke. However, this does not truly reflect exposure conditions that occur in smokers. Thus in vitro cell culture systems are required in which cells are exposed to tobacco whole smoke (WS) at the air-liquid interface (ALI). In this study bronchial epithelial cells were cultured on semi-permeable membranes, transitioned to the ALI and the robustness and sensitivity of the cells to tobacco WS and vapour phase (VP) assessed. Although no effect of air exposure was observed on cell viability, IL-6 and IL-8 release was increased. Exposure to WS resulted in a significant dose dependent decrease in cell viability and a significant non-dose dependent increase in inflammatory mediator secretion. The VP was found to contribute approximately 90% of the total cytotoxicity derived from WS. The cell culture system was also able to differentiate between two smoking regimens and was sensitive to passage number with increased inflammatory mediator secretion and lower cell viability observed in cell cultures of low passage number following WS exposure. This simple cell culture system may facilitate studies on the toxicological impact of future tobacco products and nicotine delivery devices.

  2. A new computer-controlled air-liquid interface cultivation system for the generation of differentiated cell cultures of the airway epithelium.

    PubMed

    Aufderheide, Michaela; Förster, Christine; Beschay, Morris; Branscheid, Detlev; Emura, Makito

    2016-01-01

    The increased application of in vitro systems in pharmacology and toxicology requires cell culture systems that facilitate the cultivation process and ensure stable, reproducible and controllable cultivation conditions. Up to now, some devices have been developed for the cultivation of cells under submersed conditions. However, systems meeting the requirements of an air-liquid interface (ALI) cultivation for the special needs of bronchial epithelial cells for example are still lacking. In order to obtain in vivo like organization and differentiation of these cells they need to be cultivated under ALI conditions on microporous membranes in direct contact with the environmental atmosphere. For this purpose, a Long-Term-Cultivation system was developed (CULTEX(®) LTC-C system) for the computer-controlled cultivation of such cells. The transwell inserts are placed in an incubator module (24 inserts), which can be adjusted for the medium level (ultrasonic pulse-echosensor), time and volume-dependent medium exchange, and frequency for mixing the medium with a rotating disc for homogeneous distribution of medium and secretion components. Normal primary freshly isolated bronchial epithelial cells were cultivated for up to 38 days to show the efficiency of such a cultivation procedure for generating 3D cultures exhibiting in vivo-like pseudostratified organization of the cells as well as differentiation characteristics like mucus-producing and cilia-forming cells.

  3. Characterisation of pellicles formed by Acinetobacter baumannii at the air-liquid interface.

    PubMed

    Nait Chabane, Yassine; Marti, Sara; Rihouey, Christophe; Alexandre, Stéphane; Hardouin, Julie; Lesouhaitier, Olivier; Vila, Jordi; Kaplan, Jeffrey B; Jouenne, Thierry; Dé, Emmanuelle

    2014-01-01

    The clinical importance of Acinetobacter baumannii is partly due to its natural ability to survive in the hospital environment. This persistence may be explained by its capacity to form biofilms and, interestingly, A. baumannii can form pellicles at the air-liquid interface more readily than other less pathogenic Acinetobacter species. Pellicles from twenty-six strains were morphologically classified into three groups: I) egg-shaped (27%); II) ball-shaped (50%); and III) irregular pellicles (23%). One strain representative of each group was further analysed by Brewster's Angle Microscopy to follow pellicle development, demonstrating that their formation did not require anchoring to a solid surface. Total carbohydrate analysis of the matrix showed three main components: Glucose, GlcNAc and Kdo. Dispersin B, an enzyme that hydrolyzes poly-N-acetylglucosamine (PNAG) polysaccharide, inhibited A. baumannii pellicle formation, suggesting that this exopolysaccharide contributes to pellicle formation. Also associated with the pellicle matrix were three subunits of pili assembled by chaperon-usher systems: the major CsuA/B, A1S_1510 (presented 45% of identity with the main pilin F17-A from enterotoxigenic Escherichia coli pili) and A1S_2091. The presence of both PNAG polysaccharide and pili systems in matrix of pellicles might contribute to the virulence of this emerging pathogen.

  4. Characterisation of Pellicles Formed by Acinetobacter baumannii at the Air-Liquid Interface

    PubMed Central

    Nait Chabane, Yassine; Marti, Sara; Rihouey, Christophe; Alexandre, Stéphane; Hardouin, Julie; Lesouhaitier, Olivier; Vila, Jordi; Kaplan, Jeffrey B.; Jouenne, Thierry; Dé, Emmanuelle

    2014-01-01

    The clinical importance of Acinetobacter baumannii is partly due to its natural ability to survive in the hospital environment. This persistence may be explained by its capacity to form biofilms and, interestingly, A. baumannii can form pellicles at the air-liquid interface more readily than other less pathogenic Acinetobacter species. Pellicles from twenty-six strains were morphologically classified into three groups: I) egg-shaped (27%); II) ball-shaped (50%); and III) irregular pellicles (23%). One strain representative of each group was further analysed by Brewster’s Angle Microscopy to follow pellicle development, demonstrating that their formation did not require anchoring to a solid surface. Total carbohydrate analysis of the matrix showed three main components: Glucose, GlcNAc and Kdo. Dispersin B, an enzyme that hydrolyzes poly-N-acetylglucosamine (PNAG) polysaccharide, inhibited A. baumannii pellicle formation, suggesting that this exopolysaccharide contributes to pellicle formation. Also associated with the pellicle matrix were three subunits of pili assembled by chaperon-usher systems: the major CsuA/B, A1S_1510 (presented 45% of identity with the main pilin F17-A from enterotoxigenic Escherichia coli pili) and A1S_2091. The presence of both PNAG polysaccharide and pili systems in matrix of pellicles might contribute to the virulence of this emerging pathogen. PMID:25360550

  5. Quantitative analysis of amyloid-integrated biofilms formed by uropathogenic Escherichia coli at the air-liquid interface.

    PubMed

    Wu, Cynthia; Lim, Ji Youn; Fuller, Gerald G; Cegelski, Lynette

    2012-08-08

    Bacterial biofilms are complex multicellular assemblies, characterized by a heterogeneous extracellular polymeric matrix, that have emerged as hallmarks of persistent infectious diseases. New approaches and quantitative data are needed to elucidate the composition and architecture of biofilms, and such data need to be correlated with mechanical and physicochemical properties that relate to function. We performed a panel of interfacial rheological measurements during biofilm formation at the air-liquid interface by the Escherichia coli strain UTI89, which is noted for its importance in studies of urinary tract infection and for its assembly of functional amyloid fibers termed curli. Brewster-angle microscopy and measurements of the surface elasticity (G(s)') and stress-strain response provided sensitive and quantitative parameters that revealed distinct stages during bacterial colonization, aggregation, and eventual formation of a pellicle at the air-liquid interface. Pellicles that formed under conditions that upregulate curli production exhibited an increase in strength and viscoelastic properties as well as a greater ability to recover from stress-strain perturbation. The results suggest that curli, as hydrophobic extracellular amyloid fibers, enhance the strength, viscoelasticity, and resistance to strain of E. coli biofilms formed at the air-liquid interface.

  6. Increased transfer of a multidrug resistance plasmid in Escherichia coli biofilms at the air-liquid interface.

    PubMed

    Król, Jaroslaw E; Nguyen, Hung Duc; Rogers, Linda M; Beyenal, Haluk; Krone, Stephen M; Top, Eva M

    2011-08-01

    Although biofilms represent a common bacterial lifestyle in clinically and environmentally important habitats, there is scant information on the extent of gene transfer in these spatially structured populations. The objective of this study was to gain insight into factors that affect transfer of the promiscuous multidrug resistance plasmid pB10 in Escherichia coli biofilms. Biofilms were grown in different experimental settings, and plasmid transfer was monitored using laser scanning confocal microscopy and plate counting. In closed flow cells, plasmid transfer in surface-attached submerged biofilms was negligible. In contrast, a high plasmid transfer efficiency was observed in a biofilm floating at the air-liquid interface in an open flow cell with low flow rates. A vertical flow cell and a batch culture biofilm reactor were then used to detect plasmid transfer at different depths away from the air-liquid interface. Extensive plasmid transfer occurred only in a narrow zone near that interface. The much lower transfer frequencies in the lower zones coincided with rapidly decreasing oxygen concentrations. However, when an E. coli csrA mutant was used as the recipient, a thick biofilm was obtained at all depths, and plasmid transfer occurred at similar frequencies throughout. These results and data from separate aerobic and anaerobic matings suggest that oxygen can affect IncP-1 plasmid transfer efficiency, not only directly but also indirectly, through influencing population densities and therefore colocalization of donors and recipients. In conclusion, the air-liquid interface can be a hot spot for plasmid-mediated gene transfer due to high densities of juxtaposed donor and recipient cells.

  7. Trade-off between oxygen and iron acquisition in bacterial cells at the air-liquid interface.

    PubMed

    Yamamoto, Kyosuke; Arai, Hiroyuki; Ishii, Masaharu; Igarashi, Yasuo

    2011-07-01

    The air-liquid interface is a selectively advantageous niche for aerobes due to the accessibility to oxygen. Various species of aerobes form a biofilm-like structure at air-liquid interfaces, known as a pellicle. Although the pellicle is one of the major growth modes of microorganisms, the metabolic features of pellicle cells and the determinative factors for pellicle formation are largely unknown. In this study, we investigated the factors affecting pellicle growth by the facultative aerobe Pseudomonas aeruginosa, and also examined the gene expression profiles of pellicle cells in order to characterize features of the pellicle lifestyle. A mutant strain deficient in the production of exopolysaccharides displayed poor pellicle-forming ability and a growth disadvantage under static conditions compared with the wild-type strain. Notably, supplementation of culture medium with an alternative electron acceptor, nitrate, led to diminished pellicle formation. Nitrate facilitated the growth of an anaerobic planktonic cell subpopulation that acted as a competitor for iron with the aerobic subpopulation, resulting in the observed pellicle reduction. Transcriptome analysis revealed that pellicle cells were under aerobic and iron-depleted states. Thus, although pellicle formation certainly confers a growth advantage under static conditions, pellicle cells face a nutritional trade-off between oxygen and iron acquisition.

  8. JAliEn - A new interface between the AliEn jobs and the central services

    NASA Astrophysics Data System (ADS)

    Grigoras, A. G.; Grigoras, C.; Pedreira, M. M.; Saiz, P.; Schreiner, S.

    2014-06-01

    Since the ALICE experiment began data taking in early 2010, the amount of end user jobs on the AliEn Grid has increased significantly. Presently 1/3 of the 40K CPU cores available to ALICE are occupied by jobs submitted by about 400 distinct users, individually or in organized analysis trains. The overall stability of the AliEn middleware has been excellent throughout the 3 years of running, but the massive amount of end-user analysis and its specific requirements and load has revealed few components which can be improved. One of them is the interface between users and central AliEn services (catalogue, job submission system) which we are currently re-implementing in Java. The interface provides persistent connection with enhanced data and job submission authenticity. In this paper we will describe the architecture of the new interface, the ROOT binding which enables the use of a single interface in addition to the standard UNIX-like access shell and the new security-related features.

  9. An Air-Liquid Interface Culture System for 3D Organoid Culture of Diverse Primary Gastrointestinal Tissues.

    PubMed

    Li, Xingnan; Ootani, Akifumi; Kuo, Calvin

    2016-01-01

    Conventional in vitro analysis of gastrointestinal epithelium usually relies on two-dimensional (2D) culture of epithelial cell lines as monolayer on impermeable surfaces. However, the lack of context of differentiation and tissue architecture in 2D culture can hinder the faithful recapitulation of the phenotypic and morphological characteristics of native epithelium. Here, we describe a robust long-term three-dimensional (3D) culture methodology for gastrointestinal culture, which incorporates both epithelial and mesenchymal/stromal components into a collagen-based air-liquid interface 3D culture system. This system allows vigorously expansion of primary gastrointestinal epithelium for over 60 days as organoids with both proliferation and multilineage differentiation, indicating successful long-term intestinal culture within a microenvironment accurately recapitulating the stem cell niche.

  10. Growth of airway epithelial cells at an air-liquid interface changes both the response to particle exposure and iron homeostasis

    EPA Science Inventory

    We tested the hypothesis that 1) relative to submerged cells, airway epithelial cells grown at an air-liquid interface and allowed to differentiate would have an altered response to particle exposure and 2) that these differences would be associated with indices of iron homeostas...

  11. Growth of airway epithelial cells at an air-liquid interface changes both the response to particle exposure and iron homeostasis.

    EPA Science Inventory

    RATIONALE: We tested the hypothesis that 1) relative to submerged cells, airway epithelial cells grown at an air-liquid interface and allowed to differentiate would have an altered response to particle exposure and 2) that these differences would be associated with indices of iro...

  12. Pulmonary surfactant and macrophages studied at the air/liquid interface revealed by Brewster angle microscopy (BAM)

    NASA Astrophysics Data System (ADS)

    Telesford, Dana-Marie; Allen, Heather; Carlson, Tracy; Schlesinger, Larry

    2012-04-01

    The alveolus is lined with a complex mixture of lipids and proteins called pulmonary surfactant (PS) that lower surface tension at the alveolar air/liquid interface. The surface area of the lung for a 70 kg adult human at total lung capacity is ˜70 m^2. The large surface area and the direct exposure to the environment with every inhalation make this organ more susceptible to invasion by viruses, bacteria, and small particles. The most abundant cell recovered in human lung lavage is the alveolar macrophage which accounts for 85% of the total. The primary function of the alveolar macrophage is to defend the lung against invasion, but also in the clearance of surfactant components in the lung. Quintero and Wright,^1 in an in vitro study observing alveolar macrophage metabolism of two lipid components dipalmitoyl phosphatidylglycerol (DPPG) and dipalmitoyl phosphatidylcholine (DPPC), noted that DPPG was removed at a faster rate. The mechanism by which this process takes place is not fully understood and our aim is to investigate the interactions of macrophages with different lipids using Brewster angle microscopy. Preliminary studies suggest that THP-1 differentiated macrophages do not significantly perturb DPPC and DPPG monolayers and research utilizing alveolar macrophages is underway. The effect of PS SP-A and SP-D is also discussed.

  13. Magnetic Nanodrug Delivery Through the Mucus Layer of Air-Liquid Interface Cultured Primary Normal Human Tracheobronchial Epithelial Cells.

    PubMed

    Economou, E C; Marinelli, S; Smith, M C; Routt, A A; Kravets, V V; Chu, H W; Spendier, K; Celinski, Z J

    2016-09-01

    Superparamagnetic iron oxide (Fe3O4) and highly anisotropic barium hexaferrite (BaFe12O19) nanoparticles were coated with an anti-inflammatory drug and magnetically transported through mucus produced by primary human airway epithelial cells. Using wet planetary ball milling, dl-2-amino-3-phosphonopropionic acid-coated BaFe12O19 nano-particles (BaNPs) of 1-100 nm in diameter were prepared in water. BaNPs and conventional 20-30-nm Fe3O4 nanoparticles (FeNPs) were then encased in a polymer (PLGA) loaded with dexamethasone (Dex) and tagged for imaging. PLGA-Dex-coated BaNPs and FeNPs were characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID) magnetometry. Both PLGA-Dex-coated BaNPs and FeNPs were transferred to the surface of a ~100-μm thick mucus layer of air-liquid interface cultured primary normal human tracheobronchial epithelial (NHTE) cells. Within 30 min, the nanoparticles were pulled successfully through the mucus layer by a permanent neodymium magnet. The penetration time of the nanomedicine was monitored using confocal microscopy and tailored by varying the thickness of the PLGA-Dex coating around the particles.

  14. Magnetic Nanodrug Delivery Through the Mucus Layer of Air-Liquid Interface Cultured Primary Normal Human Tracheobronchial Epithelial Cells

    PubMed Central

    Economou, E. C.; Marinelli, S.; Smith, M. C.; Routt, A. A.; Kravets, V. V.; Chu, H. W.; Spendier, K.; Celinski, Z. J.

    2016-01-01

    Superparamagnetic iron oxide (Fe3O4) and highly anisotropic barium hexaferrite (BaFe12O19) nanoparticles were coated with an anti-inflammatory drug and magnetically transported through mucus produced by primary human airway epithelial cells. Using wet planetary ball milling, dl-2-amino-3-phosphonopropionic acid-coated BaFe12O19 nano-particles (BaNPs) of 1–100 nm in diameter were prepared in water. BaNPs and conventional 20–30-nm Fe3O4 nanoparticles (FeNPs) were then encased in a polymer (PLGA) loaded with dexamethasone (Dex) and tagged for imaging. PLGA-Dex-coated BaNPs and FeNPs were characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID) magnetometry. Both PLGA-Dex-coated BaNPs and FeNPs were transferred to the surface of a ~100-μm thick mucus layer of air-liquid interface cultured primary normal human tracheobronchial epithelial (NHTE) cells. Within 30 min, the nanoparticles were pulled successfully through the mucus layer by a permanent neodymium magnet. The penetration time of the nanomedicine was monitored using confocal microscopy and tailored by varying the thickness of the PLGA-Dex coating around the particles. PMID:27774374

  15. Lung toxicity determination by in vitro exposure at the air liquid interface with an integrated online dose measurement

    NASA Astrophysics Data System (ADS)

    Mülhopt, Sonja; Diabaté, S.; Krebs, T.; Weiss, C.; Paur, H.-R.

    2009-05-01

    Epidemiological studies show an association between the concentration of ultrafine particles in the atmosphere and the rate of mortality or morbidity due to respiratory and cardiovascular diseases. For the quantitative assessment of the toxicity of airborne nanoparticles the dose-response relationship is tested in in vitro test systems using bioassays of cell cultures as sensor. For the air-liquid interface exposure of cell cultures towards aerosols the Karlsruhe exposure system was developed. The human lung cell cultures are exposed in VITROCELL® system modules with a constant flow of the conditioned aerosol. After exposure the cells are analyzed to measure the biological responses such as viability, inflammatory or oxidative stress. For the determination of the dose response relationship the accurate knowledge of the deposited particle mass is essential. A new online method is developed in the Karlsruhe exposure system: the sensor of a quartz crystal microbalance is placed in an exposure chamber instead of the membrane insert and exposed to the aerosol in the same way as the cell cultures. The deposited mass per area unit is monitored as a function of exposure time showing a linear relationship for a constant aerosol flow with defined particle concentration. A comparison of this new dose signal to a dosimetry method using fluorescein sodium particles shows a very good correlation between the sensor signal of the quartz crystal microbalance and the deposited mass on the membranes shown by spectroscopy. This system for the first time provides an online dose measurement for in vitro experiments with nanoparticles.

  16. Role of conductivity in the electrohydrodynamic patterning of air-liquid interfaces.

    PubMed

    Gambhire, P; Thaokar, R M

    2012-09-01

    The effect of electrical conductivity on the wavelength of an electrohydrodynamic instability of a leaky dielectric-perfect dielectric (LD-PD) fluid interface is investigated. For instabilities induced by dc fields, two models, namely the PD-PD model, which is independent of the conductivity, and the LD-PD model, which shows very weak dependence on the conductivity of the LD fluid, have been previously suggested. In the past, experiments have been compared with either of these two models. In the present work, experiments, analytical theory, and simulations are used to elucidate the dependence of the wavelength obtained under dc fields on the ratio of the instability time (τs=1/smax) and the charge relaxation time (τc=εε0/σ, where ε0 is the permittivity of vacuum, ε is the dielectric constant, and σ is the electrical conductivity). Sensitive dependence of the wavelength on the nondimensional conductivity S2=σ2μ2h0(2)/(ε0(2)φ0(2)δ2) (where σ2 is the electrical conductivity, μ2 is the viscosity, h0 is the thickness of the thin liquid film, φ0 is the rms value of the applied field, and δ is a small parameter) is observed and the PD-PD and the LD-PD cases are observed only as limiting behaviors at very low and very high values of S2, respectively. Under an alternating field, the frequency of the applied voltage can be altered to realize several regimes of relative magnitudes of the three time scales inherent to the system, namely τc, τs, and the time period of the applied field, τf. The wavelength in the various regimes that result from a systematic variation of these three time scales is studied. It is observed that the linear Floquet theory is invalid in most of these regimes and nonlinear analysis is used to complement it. Systematic dependence of the wavelength of the instability on the frequency of the applied field is presented and it is demonstrated that nonlinear simulations are necessary to explain the experimental results.

  17. Effects and uptake of gold nanoparticles deposited at the air-liquid interface of a human epithelial airway model

    SciTech Connect

    Brandenberger, C.; Rothen-Rutishauser, B.; Muehlfeld, C.; Schmid, O.; Ferron, G.A.; Maier, K.L.; Gehr, P.; Lenz, A.-G.

    2010-01-01

    The impact of nanoparticles (NPs) in medicine and biology has increased rapidly in recent years. Gold NPs have advantageous properties such as chemical stability, high electron density and affinity to biomolecules, making them very promising candidates as drug carriers and diagnostic tools. However, diverse studies on the toxicity of gold NPs have reported contradictory results. To address this issue, a triple cell co-culture model simulating the alveolar lung epithelium was used and exposed at the air-liquid interface. The cell cultures were exposed to characterized aerosols with 15 nm gold particles (61 ng Au/cm{sup 2} and 561 ng Au/cm{sup 2} deposition) and incubated for 4 h and 24 h. Experiments were repeated six times. The mRNA induction of pro-inflammatory (TNFalpha, IL-8, iNOS) and oxidative stress markers (HO-1, SOD2) was measured, as well as protein induction of pro- and anti-inflammatory cytokines (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, GM-CSF, TNFalpha, INFgamma). A pre-stimulation with lipopolysaccharide (LPS) was performed to further study the effects of particles under inflammatory conditions. Particle deposition and particle uptake by cells were analyzed by transmission electron microscopy and design-based stereology. A homogeneous deposition was revealed, and particles were found to enter all cell types. No mRNA induction due to particles was observed for all markers. The cell culture system was sensitive to LPS but gold particles did not cause any synergistic or suppressive effects. With this experimental setup, reflecting the physiological conditions more precisely, no adverse effects from gold NPs were observed. However, chronic studies under in vivo conditions are needed to entirely exclude adverse effects.

  18. Exposure of silver-nanoparticles and silver-ions to lung cells in vitro at the air-liquid interface

    PubMed Central

    2013-01-01

    Background Due to its antibacterial properties, silver (Ag) has been used in more consumer products than any other nanomaterial so far. Despite the promising advantages posed by using Ag-nanoparticles (NPs), their interaction with mammalian systems is currently not fully understood. An exposure route via inhalation is of primary concern for humans in an occupational setting. Aim of this study was therefore to investigate the potential adverse effects of aerosolised Ag-NPs using a human epithelial airway barrier model composed of A549, monocyte derived macrophage and dendritic cells cultured in vitro at the air-liquid interface. Cell cultures were exposed to 20 nm citrate-coated Ag-NPs with a deposition of 30 and 278 ng/cm2 respectively and incubated for 4 h and 24 h. To elucidate whether any effects of Ag-NPs are due to ionic effects, Ag-Nitrate (AgNO3) solutions were aerosolised at the same molecular mass concentrations. Results Agglomerates of Ag-NPs were detected at 24 h post exposure in vesicular structures inside cells but the cellular integrity was not impaired upon Ag-NP exposures. Minimal cytotoxicity, by measuring the release of lactate dehydrogenase, could only be detected following a higher concentrated AgNO3-solution. A release of pro-inflammatory markers TNF-α and IL-8 was neither observed upon Ag-NP and AgNO3 exposures as well as was not affected when cells were pre-stimulated with lipopolysaccharide (LPS). Also, an induction of mRNA expression of TNF-α and IL-8, could only be observed for the highest AgNO3 concentration alone or even significantly increased when pre-stimulated with LPS after 4 h. However, this effect disappeared after 24 h. Furthermore, oxidative stress markers (HMOX-1, SOD-1) were expressed after 4 h in a concentration dependent manner following AgNO3 exposures only. Conclusions With an experimental setup reflecting physiological exposure conditions in the human lung more realistic, the present study indicates that Ag

  19. Self-assembly mechanism of nanoparticles of Ni-based Prussian Blue analogues at the air/liquid interface: a synchrotron X-ray reflectivity study.

    PubMed

    Giner-Casares, Juan J; Clemente-León, Miguel; Coronado, Eugenio; Brezesinski, Gerald

    2015-08-24

    Prussian Blue analogue (PBA) nanoparticles can be self-assembled at air/liquid interfaces to build novel materials with interesting magnetic features. Herein, we study the influence of the size of PBA Cs0.4 Ni[Cr(CN)6 ]0.9 and K0.25 Ni[Fe(CN)6 ]0.75 nanoparticles on the self-assembly behavior by synchrotron X-ray reflectivity. Both nanoparticles show similar Z-potential values. The phospholipid dipalmitoylphosphatidylcholine and the amino surfactant dimethyldioctadecylammonium have been used as Langmuir monolayers to anchor the PBA nanoparticles and study the interplay of forces directing the self-assembly of the nanoparticles at the surfactant/liquid interface. Whereas Cs0.4 Ni[Cr(CN)6 ]0.9 nanoparticles with a diameter of 8 nm form an incomplete layer at the surfactant/water interface, the larger K0.25 Ni[Fe(CN)6 ]0.75 nanoparticles with a diameter of 20 nm generate complete layers that can be stacked to one another. The size of the PBA nanoparticles is the main parameter determining the final arrangement at the air/liquid interface, due to the different extent of interparticle interaction. This study aims at the rationale design of PBA nanoparticles for an effective interfacial self-assembly, ultimately leading to functional materials.

  20. Infrared spectroscopy analysis of mixed DPPC/fibrinogen layer behavior at the air/liquid interface under a continuous compression-expansion condition.

    PubMed

    Yin, Chia-Lin; Chang, Chien-Hsiang

    2006-07-18

    The mixed layer behavior of dipalmitoyl phosphatidylcholine (DPPC) with fibrinogen at continuously compressed-expanded air/liquid interfaces was analyzed in situ by infrared reflection-absorption spectroscopy (IRRAS). The reflectance-absorbance (RA) intensities and/or wavenumbers of nu(a)-CH2 and amide I bands for a mixed DPPC/fibrinogen layer at the interface were obtained directly by an infrared spectrometer with a monolayer/grazing angle accessory and a removable Langmuir trough. The nu(a)-CH2 RA intensity-area hysteresis curves of a DPPC monolayer indicate a significant loss of free DPPC molecules at the interface during the first compression stage, which is also supported by the corresponding nu(a)-CH2 wavenumber-area hysteresis curves. For a mixed DPPC/fibrinogen layer at the interface, the amide I RA intensity-area hysteresis curves suggest that the fibrinogen molecules were expelled from the interface upon compression, apparently because of the presence of insoluble DPPC molecules. The squeeze-out of fibrinogen evidently removed a pronounced amount of DPPC from the interface, as judged from the corresponding nu(a)-CH2 intensity and wavenumber data. Moreover, significant adsorption of fibrinogen was found during the subsequent interface expansion stage. With the in situ IRRAS analysis of the mixed layer behavior at the interface, the induced loss of DPPC by fibrinogen expulsion from the compressed interface and the dominant adsorption of fibrinogen to the expanded interface were clearly demonstrated.

  1. The adherence of Salmonella Enteritidis PT4 to stainless steel: the importance of the air-liquid interface and nutrient availability.

    PubMed

    Giaouris, Efstathios D; Nychas, George-John E

    2006-12-01

    Biofilm formation on stainless steel by Salmonella enterica serovar Enteritidis PT4 during growth in three different nutritious conditions was studied. The ability of micro-organisms to generate biofilms on the stainless steel surfaces was studied for a total period of 18 days at 20 degrees C, under three different experimental treatments: (i) growth medium (tryptone soy broth) was not refreshed (no further nutrients were provided) during the incubation period, (ii) growth medium was renewed every 2 days and (iii) growth medium was renewed every 2 days and at the same time the planktonic cells from the old medium were transferred to the new fresh medium. It was found that biofilms developed better and a higher number of adherent cells (ca. 10(7) cfu/cm(2)) were recovered when the organism was grown in periodically renewed nutrient medium than when the growth medium was not refreshed. Regardless of the availability of nutrients, biofilm development was better (range 2-3 logs greater) when coupons were not totally covered by the growth medium and part of the surface was exposed to the air-liquid interface, than when coupons were submerged in the medium. The results suggest that existence of air-liquid interface and adequate nutrient conditions provide the best environment for Salmonella Enteritidis PT4 biofilm formation on stainless steel. The possible role of stationary phase planktonic cells in biofilm development by sessile/attached microbial cells is also discussed.

  2. A method to form semiconductor quantum dot (QD) thin films by igniting a flame at air-liquid interface: CdS and WO3.

    PubMed

    Jadhav, Aarti H; Patil, Sagar H; Sathaye, Shivaram D; Patil, Kashinath R

    2015-02-01

    We reveal an easy, inexpensive, efficient one stepflame synthesis of semiconductor/metal oxide thin films at air-liquid interface, subsequently, transferred on suitable substrate. The method has been illustrated by the formation of CdS and WO3 QDs thin films. The features of the present method are (1) Growth of thin films consisting of0.5-2.0nm sized Quantum Dots (QDs)/(ultra-small nanoparticles) in a short time, at the air-liquid interface which can be suitably transferred by a well-known Blodgett technique to an appropriate substrate, (2) The method is suitable to apply layer by layer (LbL) technique to increase the film thickness as well as forming various compositions as revealed by AFM measurements. The films are characterized for their structure (SAED), morphology (TEM), optical properties (UV-Vis.) and photoluminescence (PL). Possible mechanism of formation of QDs thin film and effect of capping in case of CdS QDs is discussed.

  3. Effects of aggregates on mixed adsorption layers of poly(ethylene imine) and sodium dodecyl sulfate at the air/liquid interface.

    PubMed

    Tonigold, Katrin; Varga, Imre; Nylander, Tommy; Campbell, Richard A

    2009-04-07

    We have exploited the spatial and kinetic resolution of ellipsometry to monitor the lateral movement of inhomogeneous patches of material in mixed adsorption layers of poly(ethylene imine) and sodium dodecyl sulfate at the air/liquid interface. We show that the choice of sample preparation methods can have a profound effect on the state of the interface for chemically equivalent samples. The extent of aggregation in the bulk solution on relevant time scales is affected by specific details of the polymer/surfactant mixing process, which produces varying numbers of aggregates that can become trapped in the interfacial layer, resulting in an enhanced and fluctuating ellipsometry signal. It can be beneficial to apply the surface-cleaning method of aspiration prior to physical measurements to remove trapped aggregates through the creation of a fresh interface. At low pH, the ellipsometry signal of samples prepared with surface cleaning is remarkably constant over a factor of >500 in the bulk composition below charge equivalence, which is discussed in terms of possible adsorption mechanisms. At high pH, through observing temporal fluctuations in the ellipsometry signal of samples prepared with surface cleaning, we reveal two important processes: there is the spontaneous adsorption of aggregates > 0.2 microm in diameter into the interfacial layer, and with time there is the fusion of smaller aggregates to generate new large surface aggregates. We attribute the favorability of the adsorption and fusion processes at high pH to reduced electrostatic barriers resulting from the low surface charge density of the aggregates. It is inappropriate in this case to consider the interface to comprise a homogeneous adsorption layer that is in dynamic equilibrium with the bulk solution. Our work shows that it can be helpful to consider whether there are macroscopic particles embedded in molecular layers at the air/liquid interface for systems where there is prior knowledge of

  4. Anomalous effective polarity of an air/liquid-mixture interface: a heterodyne-detected electronic and vibrational sum frequency generation study.

    PubMed

    Mondal, Sudip Kumar; Inoue, Ken-ichi; Yamaguchi, Shoichi; Tahara, Tahei

    2015-10-07

    We study the effective polarity of an air/liquid-mixture interface by using interface-selective heterodyne-detected electronic sum frequency generation (HD-ESFG) and vibrational sum frequency generation (HD-VSFG) spectroscopies. With water and N,N-dimethylformamide (DMF) chosen as two components of the liquid mixture, the bulk polarity of the mixture is controlled nearly arbitrarily by the mixing ratio. The effective polarity of the air/mixture interface is evaluated by HD-ESFG with a surface-active solvatochromic molecule used as a polarity indicator. Surprisingly, the interfacial effective polarity of the air/mixture interface increases significantly, when the bulk polarity of the mixture decreases (i.e. when the fraction of DMF increases). Judging from the hydrogen-bond structure at the air/mixture interface clarified by HD-VSFG, this anomalous change of the interfacial effective polarity is attributed to the interface-specific solvation structure around the indicator molecule at the air/mixture interface.

  5. Validation of an air-liquid interface toxicological set-up using Cu, Pd, and Ag well-characterized nanostructured aggregates and spheres

    NASA Astrophysics Data System (ADS)

    Svensson, C. R.; Ameer, S. S.; Ludvigsson, L.; Ali, N.; Alhamdow, A.; Messing, M. E.; Pagels, J.; Gudmundsson, A.; Bohgard, M.; Sanfins, E.; Kåredal, M.; Broberg, K.; Rissler, J.

    2016-04-01

    Systems for studying the toxicity of metal aggregates on the airways are normally not suited for evaluating the effects of individual particle characteristics. This study validates a set-up for toxicological studies of metal aggregates using an air-liquid interface approach. The set-up used a spark discharge generator capable of generating aerosol metal aggregate particles and sintered near spheres. The set-up also contained an exposure chamber, The Nano Aerosol Chamber for In Vitro Toxicity (NACIVT). The system facilitates online characterization capabilities of mass mobility, mass concentration, and number size distribution to determine the exposure. By dilution, the desired exposure level was controlled. Primary and cancerous airway cells were exposed to copper (Cu), palladium (Pd), and silver (Ag) aggregates, 50-150 nm in median diameter. The aggregates were composed of primary particles <10 nm in diameter. For Cu and Pd, an exposure of sintered aerosol particles was also produced. The doses of the particles were expressed as particle numbers, masses, and surface areas. For the Cu, Pd, and Ag aerosol particles, a range of mass surface concentrations on the air-liquid interface of 0.4-10.7, 0.9-46.6, and 0.1-1.4 µg/cm2, respectively, were achieved. Viability was measured by WST-1 assay, cytokines (Il-6, Il-8, TNF-a, MCP) by Luminex technology. Statistically significant effects and dose response on cytokine expression were observed for SAEC cells after exposure to Cu, Pd, or Ag particles. Also, a positive dose response was observed for SAEC viability after Cu exposure. For A549 cells, statistically significant effects on viability were observed after exposure to Cu and Pd particles. The set-up produced a stable flow of aerosol particles with an exposure and dose expressed in terms of number, mass, and surface area. Exposure-related effects on the airway cellular models could be asserted.

  6. Studies of molecular monolayers at air-liquid interfaces by second harmonic generation: question of orientational phase transition

    SciTech Connect

    Rasing, T.; Shen, Y.R.; Kim, M.W.; Grubb, S.; Bock, J.

    1985-06-01

    Insoluble molecular monolayers at gas-liquid interfaces provide an insight to the understanding of surfactants, wetting, microemulsions and membrane structures and offer a possibility to study the rich world of 2-dimensional phase transitions. In the interpretation of the observed properties of these systems various assumptions about the molecular orientation are often made, but so far few clear experimental data exist. In this paper we will show how optical second harmonic generation (SHG) can be used to measure the molecular orientation of monolayers of surfactant molecules at water-air interfaces. By simultaneously measuring the surface pressure versus surface molecular area we can show for the first time that the observed liquid condensed-liquid expanded transition is an orientational phase transition. 7 refs., 4 figs.

  7. Human bronchial epithelial cells exposed in vitro to cigarette smoke at the air-liquid interface resemble bronchial epithelium from human smokers.

    PubMed

    Mathis, Carole; Poussin, Carine; Weisensee, Dirk; Gebel, Stephan; Hengstermann, Arnd; Sewer, Alain; Belcastro, Vincenzo; Xiang, Yang; Ansari, Sam; Wagner, Sandra; Hoeng, Julia; Peitsch, Manuel C

    2013-04-01

    Organotypic culture of human primary bronchial epithelial cells is a useful in vitro system to study normal biological processes and lung disease mechanisms, to develop new therapies, and to assess the biological perturbations induced by environmental pollutants. Herein, we investigate whether the perturbations induced by cigarette smoke (CS) and observed in the epithelium of smokers' airways are reproducible in this in vitro system (AIR-100 tissue), which has been shown to recapitulate most of the characteristics of the human bronchial epithelium. Human AIR-100 tissues were exposed to mainstream CS for 7, 14, 21, or 28 min at the air-liquid interface, and we investigated various biological endpoints [e.g., gene expression and microRNA profiles, matrix metalloproteinase 1 (MMP-1) release] at multiple postexposure time points (0.5, 2, 4, 24, 48 h). By performing a Gene Set Enrichment Analysis, we observed a significant enrichment of human smokers' bronchial epithelium gene signatures derived from different public transcriptomics datasets in CS-exposed AIR-100 tissue. Comparison of in vitro microRNA profiles with microRNA data from healthy smokers highlighted various highly translatable microRNAs associated with inflammation or with cell cycle processes that are known to be perturbed by CS in lung tissue. We also found a dose-dependent increase of MMP-1 release by AIR-100 tissue 48 h after CS exposure in agreement with the known effect of CS on this collagenase expression in smokers' tissues. In conclusion, a similar biological perturbation than the one observed in vivo in smokers' airway epithelium could be induced after a single CS exposure of a human organotypic bronchial epithelium-like tissue culture.

  8. Quantum chemical approach in the description of the amphiphile clusterization at the air/liquid and liquid/liquid interfaces with phase nature accounting. I. Aliphatic normal alcohols at the air/water interface.

    PubMed

    Vysotsky, Yuri B; Belyaeva, Elena A; Kartashynska, Elena S; Fainerman, Valentine B; Smirnova, Natalia A

    2015-02-19

    A new model based on the quantum chemical approach is proposed to describe structural and thermodynamic parameters of clusterization for substituted alkanes at the air/liquid and liquid/liquid interfaces. The new model by the authors, unlike the previous one, proposes an explicit account of the liquid phase (phases) influence on the parameters of monomers, clusters and monolayers of substituted alkanes at the regarded interface. The calculations were carried out in the frameworks of the quantum chemical semiempirical PM3 method (Mopac 2012), using the COSMO procedure. The new model was tested in the calculations of the clusterization parameters of fatty alcohols under the standard conditions at the air/water interface. The enthalpy, Gibbs' energy and absolute entropy of formation for alcohol monomers alongside with clusterization parameters for the cluster series including the monolayer at air/water interface were calculated. In our calculations the sinkage of monomers, molecules in clusters and monolayers was varied from 1 up to 5 methylene groups. Thermodynamic parameters calculated using the proposed model for the alcohol monolayers are in a good agreement with the corresponding experimental data. However, the proposed model cannot define the most energetically preferable immersion of the monolayer molecules in the water phase.

  9. Phenotypic modification of human airway epithelial cells in air-liquid interface culture induced by exposure to the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK).

    PubMed

    Carson, Johnny L; Brighton, Luisa E; Jaspers, Ilona

    2015-04-01

    The nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent tobacco-specific carcinogen. We used an air-liquid interface epithelial cell culture system to model changes associated with NNK exposure relative to pathologies documented in human tobacco-related illnesses. Although in vitro systems exhibit certain limitations, they often offer accentuation of subtle pathologies. While the distribution of cell types in control cultures typically favors the ciliated cell phenotype, NNK-exposed cultures transitioned to non-ciliated cell phenotypes as well as reflecting features consistent with squamous metaplasia. We conclude that NNK impacts normal growth and differentiation of human airway epithelium in a short interval of time in vitro.

  10. Repeated whole cigarette smoke exposure alters cell differentiation and augments secretion of inflammatory mediators in air-liquid interface three-dimensional co-culture model of human bronchial tissue.

    PubMed

    Ishikawa, Shinkichi; Ito, Shigeaki

    2017-02-01

    In vitro models of human bronchial epithelium are useful for toxicological testing because of their resemblance to in vivo tissue. We constructed a model of human bronchial tissue which has a fibroblast layer embedded in a collagen matrix directly below a fully-differentiated epithelial cell layer. The model was applied to whole cigarette smoke (CS) exposure repeatedly from an air-liquid interface culture while bronchial epithelial cells were differentiating. The effects of CS exposure on differentiation were determined by histological and gene expression analyses on culture day 21. We found a decrease in ciliated cells and perturbation of goblet cell differentiation. We also analyzed the effects of CS exposure on the inflammatory response, and observed a significant increase in secretion of IL-8, GRO-α, IL-1β, and GM-CSF. Interestingly, secretion of these mediators was augmented with repetition of whole CS exposure. Our data demonstrate the usefulness of our bronchial tissue model for in vitro testing and the importance of exposure repetition in perturbing the differentiation and inflammation processes.

  11. Polysaccharide films at an air/liquid and a liquid/silicon interface: effect of the polysaccharide and liquid type on their physical properties.

    PubMed

    Taira, Yasunori; McNamee, Cathy E

    2014-11-14

    We investigated the effect of the polysaccharide type, the subphase on which the Langmuir monolayers were prepared, and the liquid in which the properties of the transferred monolayers were measured on the physical properties of the polysaccharide films at an air/aqueous interface and at a silicon substrate, and the forces and friction of the polysaccharide transferred films when measured in solution against a silica probe. Chitosan was modified with a silane coupling agent to make chitosan derived compounds with a low and a medium molecular weight. Chitin and the chitosan-derived compounds were used to make Langmuir monolayers at air/water and air/pH 9 buffer interfaces. The monolayers were transferred to silicon substrates via Langmuir-Blodgett deposition, and the chitosan-derived compounds subsequently chemically reacted with the silicon substrates. Atomic force microscope force and friction measurements were made in water and in the pH 9 buffer, where the water and the pH 9 buffer acted as a good and a bad solvent for the polysaccharides, respectively. The polysaccharide type affected the friction of the polysaccharide film, where the physically adsorbed chitin gave the lowest friction. The friction of L-chitosan was higher than that of M-chitosan in water, suggesting that the molecular weight of the polymer affects its lubricating ability. The forces and friction of the polysaccharide films changed when the subphase on which the Langmuir monolayers were formed was changed or when the liquid in which the properties of the films adsorbed at the silicon substrate were measured was changed. The friction increased significantly when the liquid was changed from water to the pH 9 buffer. This increase was explained by the reduced charge of the chitin and chitosan-derived materials due to the pH increase, the screening of the charges by the salts in the buffer, and the possible hardening of the monolayer caused by the adsorption of salts from the buffer.

  12. Ciliatoxicity in human primary bronchiolar epithelial cells after repeated exposure at the air-liquid interface with native mainstream smoke of K3R4F cigarettes with and without charcoal filter.

    PubMed

    Aufderheide, Michaela; Scheffler, Stefanie; Ito, Shigeaki; Ishikawa, Shinkichi; Emura, Makito

    2015-01-01

    Mucociliary clearance is the primary physical mechanism to protect the human airways against harmful effects of inhaled particles. Environmental factors play a significant role in the impairment of this defense mechanism, whereas cigarette smoke is discussed to be one of the clinically most important causes. Impaired mucociliary clearance in smokers has been connected to changes in ciliated cells such as decreased numbers, altered structure and beat frequency. Clinical studies have shown that cilia length is reduced in healthy smokers and that long-term exposure to cigarette smoke leads to reduced numbers of ciliated cells in mice. We present an in vitro model of primary normal human bronchiolar epithelial (NHBE) cells with in vivo like morphology to study the influence of cigarette mainstream smoke on ciliated cells. We exposed mucociliary differentiated cultures repeatedly to non-toxic concentrations of mainstream cigarette smoke (4 cigarettes, 5 days/week, 8 repetitions in total) at the air-liquid interface. Charcoal filter tipped cigarettes were compared to those being equipped with standard cellulose acetate filters. Histopathological analyses of the exposed cultures showed a reduction of cilia bearing cells, shortening of existing cilia and finally disappearance of all cilia in cigarette smoke exposed cells. In cultures exposed to charcoal filtered cigarette smoke, little changes in cilia length were seen after four exposure repetitions, but those effects were reversed after a two day recovery period. Those differences indicate that volatile organic compounds, being removed by the charcoal filter tip, affect primary bronchiolar epithelial cells concerning their cilia formation and function comparable with the in vivo situation. In conclusion, our in vitro model presents a valuable tool to study air-borne ciliatoxic compounds.

  13. ALIS deployment in Cambodia

    NASA Astrophysics Data System (ADS)

    Sato, Motoyuki; Takahashi, Kazunori

    2012-06-01

    Dual sensor is one of the most promising sensors for humanitarian demining operations. Conventional landmine detection depends on highly trained and focused human operators manually sweeping 1m2 plots with a metal detector and listening for characteristic audio signals indicating the presence of AP (Anti-personnel) landmines. In order to reduce the time of plodding detected objects, metal detectors need to be combined with a complimentary subsurface imaging sensor. i.e., GPR(Ground Penetrating Radar). The demining application requires real-time imaging results with centimetre resolution in a highly portable package. We are currently testing a dual sensor ALIS which is a real-time sensor tracking system based on a CCD camera and image processing. In this paper we introduce ALIS systems which we have developed for detection of buried antipersonnel mines and small size explosives. The performance of ALIS has been tested in Cambodia since 2009. More than 80 anti-personnel mines have been detected and removed from local agricultural area. ALIS has cleared more than 70,000 m2 area and returned it to local farmers.

  14. ALIS evaluation tests in Croatia

    NASA Astrophysics Data System (ADS)

    Sato, Motoyuki; Fujiwara, Jun; Kido, Takashi; Takahashi, Kazunori

    2009-05-01

    Tohoku University, Japan is developing a new hand-held land mine detection dual-sensor (ALIS) which is equipped with a metal detector and a GPR. ALIS is equipped with a sensor tracking system, which can record the GPR and Metal detector signal with its location. The Migration processing drastically increases the quality of the imaging of the buried objects.Evaluation test of ALIS has been conducted several test sites. Tests in real mine fields in Croatia has been conducted between December 2007 and April 2008. Under different soil and environment conditions, ALIS worked well. Then ALIS evaluation test started in Cambodia in February 2009 and we could find discrimination capability of ALIS in test lanes, and we are planning to start evaluation test in real mine fields in Cambodia.

  15. Development of prototype air/liquid solar collector subsystem

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Testing of the evacuated tubular air collector in conjunction with air/liquid heat exchange and liquid storage elements was completed. Test results emphasize matching of heat exchanger and collector characteristics with specific attention to the dynamic response of each of the elements.

  16. Tomographic inversion for ALIS noise and resolution

    NASA Astrophysics Data System (ADS)

    Gustavsson, Björn

    1998-11-01

    In this report the problems of resolution and noise sensitivity of tomographic reconstructions from ground-based multistation imaging of aurora with the auroral large imaging system (ALIS) are considered. ALIS is a ground-based grid of high-performance CCD-imaging stations at high latitudes. For evaluation of the resolution and noise sensitivity of current tomographic reconstruction procedures a full model simulation of the ALIS system is presented. The results show that relative errors are typically in the range 0.05-0.1 for typical noise levels in measurements of aurora. A general method to estimate resolution in a tomographic imaging system is developed and used to give estimates of the horizontal and vertical resolution. Its current limitations and future perspective are briefly discussed. A method to retrieve feasible tomographic reconstructions from a few image projections with variable noise level are outlined.

  17. Establishment and Characterization of an Air-Liquid Canine Corneal Organ Culture Model To Study Acute Herpes Keratitis

    PubMed Central

    Harman, Rebecca M.; Bussche, Leen; Ledbetter, Eric C.

    2014-01-01

    ABSTRACT Despite the clinical importance of herpes simplex virus (HSV)-induced ocular disease, the underlying pathophysiology of the disease remains poorly understood, in part due to the lack of adequate virus–natural-host models in which to study the cellular and viral factors involved in acute corneal infection. We developed an air-liquid canine corneal organ culture model and evaluated its susceptibility to canine herpesvirus type 1 (CHV-1) in order to study ocular herpes in a physiologically relevant natural host model. Canine corneas were maintained in culture at an air-liquid interface for up to 25 days, and no degenerative changes were observed in the corneal epithelium during cultivation using histology for morphometric analyses, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) assays, and transmission electron microscopy (TEM). Next, canine corneas were inoculated with CHV-1 for 48 h, and at that time point postinfection, viral plaques could be visualized in the corneal epithelium and viral DNA copies were detected in both the infected corneas and culture supernatants. In addition, we found that canine corneas produced proinflammatory cytokines in response to CHV-1 infection similarly to what has been described for HSV-1. This emphasizes the value of our model as a virus–natural-host model to study ocular herpesvirus infections. IMPORTANCE This study is the first to describe the establishment of an air-liquid canine corneal organ culture model as a useful model to study ocular herpesvirus infections. The advantages of this physiologically relevant model include the fact that (i) it provides a system in which ocular herpes can be studied in a virus–natural-host setting and (ii) it reduces the number of experimental animals needed. In addition, this long-term explant culture model may also facilitate research in other fields where noninfectious and infectious ocular diseases of dogs and humans are being studied. PMID

  18. The air-liquid flow in a microfluidic airway tree.

    PubMed

    Song, Yu; Baudoin, Michael; Manneville, Paul; Baroud, Charles N

    2011-09-01

    Microfluidic techniques are employed to investigate air-liquid flows in the lung. A network of microchannels with five generations is made and used as a simplified model of a section of the pulmonary airway tree. Liquid plugs are injected into the network and pushed by a flow of air; they divide at every bifurcation until they reach the exits of the network. A resistance, associated with the presence of one plug in a given generation, is defined to establish a linear relation between the driving pressure and the total flow rate in the network. Based on this resistance, good predictions are obtained for the flow of two successive plugs in different generations. The total flow rate of a two-plug flow is found to depend not only on the driving pressure and lengths of the plugs, but also the initial distance between them. Furthermore, long range interactions between daughters of a dividing plug are observed and discussed, particularly when the plugs are flowing through the bifurcations. These interactions lead to different flow patterns for different forcing conditions: the flow develops symmetrically when subjected to constant pressure or high flow rate forcing, while a low flow rate driving yields an asymmetric flow.

  19. Air-liquid biofilm formation is dependent on ammonium depletion in a Saccharomyces cerevisiae flor strain.

    PubMed

    Zara, Giacomo; Budroni, Marilena; Mannazzu, Ilaria; Zara, Severino

    2011-12-01

    Air-liquid biofilm formation appears to be an adaptive mechanism that promotes foraging of Saccharomyces cerevisiae flor strains in response to nutrient starvation. The FLO11 gene plays a central role in this phenotype as its expression allows yeast cells to rise to the liquid surface. Here, we investigated the role of ammonium depletion in air-liquid biofilm formation and FLO11 expression in a S. cerevisiae flor strain. The data obtained show that increasing ammonium concentrations from 0 to 450 m m reduce air-liquid biofilm in terms of biomass and velum formation and correlate with a reduction of FLO11 expression. Rapamycin inhibition of the TOR pathway and deletion of RAS2 gene significantly reduced biofilm formation and FLO11 expression. Taken together, these data suggest that ammonium depletion is a key factor in the induction of air-liquid biofilm formation and FLO11 expression in S. cerevisiae flor strains.

  20. Atmospheric monitoring strategy for the Ali site, Tibet

    NASA Astrophysics Data System (ADS)

    Yao, Y.; Zhou, Y.; Liu, L.; Wang, H.; Yin, J.; You, X.; Fu, X.

    2015-04-01

    The astronomical site survey in China has been carried out since 2003. Remote studies and local surveys are performed over the high plateaus, and candidate sites have been selected and performed site testing measurements. The monitoring results show that Ali area in western Tibet can be the best choice for astronomical observations over East Asian regions. Ali site, near the central town of Ali area, has been further identified for small telescope projects and simultaneously for detailed site characterization, and begun construction in 2010. This paper presents the site monitoring strategy and site development plan of the new Ali observatory.

  1. ALIS: a multistation imaging facility with possibilities for future VI applications

    NASA Astrophysics Data System (ADS)

    Brandstrom, Urban; Steen, Ake; Rydesater, Peter; Gustavsson, Bjorn; Aso, T.

    1999-03-01

    ALIS (Auroral Large Imaging System) is an imaging facility in Northern Sweden. The system consists of six unmanned, remote controlled stations. Each station has a high performance CCD imager, and some stations also have other scientific instrumentation (e.g. pulsation magnetometers). ALIS is capable of producing large amounts of data in a short time. For that reason, novel (AI/VI) techniques for data analysis, are of high priority in order to be able to handle the large data sets. In this paper we will try to describe the current implementation and address the questions of how to interface AI/VI applications to an existing multi station research facility, in terms of real- time experiment control, selective imaging, real-time data analysis, etc.

  2. Evaluation test of ALIS in Cambodia for humanitarian demining

    NASA Astrophysics Data System (ADS)

    Sato, Motoyuki

    2010-04-01

    ALIS is a hand-held dual sensor developed by Tohoku University, Japan since 2002. Dual sensor is a general name of sensor for humanitarian demining, which are equipped with metal detector and GPR. ALIS is only one hand-held dual sensor, which can record the sensor position with sensor signals. Therefore, the data can be processed after data acquisition, and can increase the imaging capability. ALIS has been tested in some mine affected courtiers including Afghanistan (2004), Egypt(2005), Croatia(2006-) and Cambodia(2007-). Mine fields at each country has different conditions and soil types. Therefore testes at the real mine fields are very important. ALIS has detected more than 30 AP-Mines in evaluation test in Cambodia held in 2009.

  3. An air-liquid interphase approach for modeling the early embryo-maternal contact zone

    PubMed Central

    Chen, S.; Palma-Vera, S. E.; Langhammer, M.; Galuska, S. P.; Braun, B. C.; Krause, E.; Lucas-Hahn, A.; Schoen, J.

    2017-01-01

    We developed an air-liquid interphase culture procedure for mammalian oviduct epithelial cells leading to the formation of functional epithelial tissues, which generate oviduct fluid surrogates. These in vitro oviduct epithelia can be co-cultured with living zygotes and enable embryonic development up to the blastocyst stage without addition of embryo culture medium. The described strategy is broadly applicable to analyze early embryo-maternal interactions under standardized in vitro conditions. PMID:28181558

  4. Prognostic Significance of Modified Advanced Lung Cancer Inflammation Index (ALI) in Patients with Small Cell Lung Cancer_ Comparison with Original ALI

    PubMed Central

    Kim, Young Saing; Seo, Ja-Young; Park, Inkeun; Ahn, Hee Kyung; Jeong, Yu Mi; Kim, Jeong Ho

    2016-01-01

    Background Advanced lung cancer inflammation index (ALI, body mass index [BMI] x serum albumin/neutrophil-lymphocyte ratio [NLR]) has been shown to predict overall survival (OS) in small cell lung cancer (SCLC). CT enables skeletal muscle to be quantified, whereas BMI cannot accurately reflect body composition. The purpose was to evaluate prognostic value of modified ALI (mALI) using CT-determined L3 muscle index (L3MI, muscle area at L3/height2) beyond original ALI. Methods L3MIs were calculated using the CT images of 186 consecutive patients with SCLC taken at diagnosis, and mALI was defined as L3MI x serum albumin/NLR. Using chi-squared test determined maximum cut-offs for low ALI and low mALI, the prognostic values of low ALI and low mALI were tested using Kaplan-Meier method and Cox proportional hazards analysis. Finally, deviance statistics was used to test whether the goodness of fit of the prognostic model is improved by adding mALI as an extra variable. Results Patients with low ALI (cut-off, 31.1, n = 94) had shorter OS than patients with high ALI (median, 6.8 months vs. 15.8 months; p < 0.001), and patients with low mALI (cut-off 67.7, n = 94) had shorter OS than patients with high mALI (median, 6.8 months vs. 16.5 months; p < 0.001). There was no significant difference in estimates of median survival time between low ALI and low mALI (z = 0.000, p = 1.000) and between high ALI and high mALI (z = 0.330, p = 0.740). Multivariable analysis showed that low ALI was an independent prognostic factor for shorter OS (HR, 1.67, p = 0.004), along with advanced age (HR, 1.49, p = 0.045), extensive disease (HR, 2.27, p < 0.001), supportive care only (HR, 7.86, p < 0.001), and elevated LDH (HR, 1.45, p = 0.037). Furthermore, goodness of fit of this prognostic model was not significantly increased by adding mALI as an extra variable (LR difference = 2.220, p = 0.136). Conclusion The present study confirms mALI using CT-determined L3MI has no additional prognostic

  5. Site Protection Program and Progress Report of Ali Observatory, Tibet

    NASA Astrophysics Data System (ADS)

    Yao, Yongqiang; Zhou, Yunhe; Wang, Xiaohua; He, Jun; Zhou, Shu

    2015-08-01

    The Ali observatory, Tibet, is a promising new site identified through ten year site survey over west China, and it is of significance to establish rules of site protection during site development. The site protection program is described with five aspects: site monitoring, technical support, local government support, specific organization, and public education. The long-term sky brightness monitoring is ready with site testing instruments and basic for light pollution measurement; the monitoring also includes directions of main light sources, providing periodical reports and suggestions for coordinating meetings. The technical supports with institutes and manufacturers help to publish lighting standards and replace light fixtures; the research pays special attention to the blue-rich sources, which impact the important application of high altitude sites. An official leading group towards development and protection of astronomical resources has been established by Ali government; one of its tasks is to issue regulations against light pollution, including special restrictions of airport, mine, and winter heating, and to supervise lighting inspection and rectification. A site protection office under the official group and local astronomical society are organized by Ali observatory; the office can coordinate in government levels and promote related activities. A specific website operated by the protection office releases activity propaganda, evaluation results, and technical comparison with other observatories. Both the site protection office and Ali observatory take responsibility for public education, including popular science lectures, light pollution and energy conservation education. Ali Night Sky Park has been constructed and opens in 2014, and provides a popular place and observational experience. The establishment of Ali Observatory and Night Sky Park brings unexpected social influence, and the starry sky trip to Ali becomes a new format of culture

  6. Enhancing the AliEn Web Service Authentication

    NASA Astrophysics Data System (ADS)

    Zhu, Jianlin; Saiz, Pablo; Carminati, Federico; Betev, Latchezar; Zhou, Daicui; Mendez Lorenzo, Patricia; Grigoras, Alina Gabriela; Grigoras, Costin; Furano, Fabrizio; Schreiner, Steffen; Vladimirovna Datskova, Olga; Sankar Banerjee, Subho; Zhang, Guoping

    2011-12-01

    Web Services are an XML based technology that allow applications to communicate with each other across disparate systems. Web Services are becoming the de facto standard that enable inter operability between heterogeneous processes and systems. AliEn2 is a grid environment based on web services. The AliEn2 services can be divided in three categories: Central services, deployed once per organization; Site services, deployed on each of the participating centers; Job Agents running on the worker nodes automatically. A security model to protect these services is essential for the whole system. Current implementations of web server, such as Apache, are not suitable to be used within the grid environment. Apache with the mod_ssl and OpenSSL only supports the X.509 certificates. But in the grid environment, the common credential is the proxy certificate for the purpose of providing restricted proxy and delegation. An Authentication framework was taken for AliEn2 web services to add the ability to accept X.509 certificates and proxy certificates from client-side to Apache Web Server. The authentication framework could also allow the generation of access control policies to limit access to the AliEn2 web services.

  7. Sidi Ali Ou Azza (L4): A New Moroccan Fall

    NASA Astrophysics Data System (ADS)

    Chennaoui Aoudjehane, H.; Agee, C. B.; Aaranson, A.; Bouragaa, A.

    2016-08-01

    Sidi Ali Ou Azza is the latest meteorite fall in Morocco, it occurred on 28 July 2015 very close (about 40 km) to Tissint martian shergottite fall that occurred on 18 July 2011. It's one of the small group of 23 L4 ordinary chondrite falls.

  8. ALIS through the Looking Glass: Changing Perceptions of Performance Indicators.

    ERIC Educational Resources Information Center

    Williamson, John; And Others

    1992-01-01

    Follows up on a Williamson and Fitz-Gibbon article (1990) focusing on the impact of a performance indicator project, COMBSE (Confidential Measurement Based Self-Evaluation), on secondary school English departments. This article describes COMBSE's metamorphosis into another system, ALIS (A Level Information System), that has transcended the…

  9. ALI--A Digital Archive of DAISY Books

    ERIC Educational Resources Information Center

    Forsberg, Asa

    2007-01-01

    ALI is a project to develop an archive for talking books produced by the Swedish universities. The universities produce talking books from the mandatory literature for students with reading disabilities, including mostly journal articles, book chapters and texts written by teachers. The project group consists of librarians and co-ordinators for…

  10. The interaction of the cellular export adaptor protein Aly/REF with ICP27 contributes to the efficiency of herpes simplex virus 1 mRNA export.

    PubMed

    Tian, Xiaochen; Devi-Rao, Gayathri; Golovanov, Alexander P; Sandri-Goldin, Rozanne M

    2013-07-01

    Herpes simplex virus 1 (HSV-1) protein ICP27 enables viral mRNA export by accessing the cellular mRNA export receptor TAP/NXF, which guides mRNA through the nuclear pore complex. ICP27 binds viral mRNAs and interacts with TAP/NXF, providing a link to the cellular mRNA export pathway. ICP27 also interacts with the mRNA export adaptor protein Aly/REF, which binds cellular mRNAs and also interacts with TAP/NXF. Studies using small interfering RNA (siRNA) knockdown indicated that Aly/REF is not required for cellular mRNA export, and similar knockdown studies during HSV-1 infection led us to conclude that Aly/REF may be dispensable for viral RNA export. Recently, the structural basis of the interaction of ICP27 with Aly/REF was elucidated at atomic resolution, and it was shown that three ICP27 residues, W105, R107, and L108, interface with the RNA recognition motif (RRM) domain of Aly/REF. Here, to determine the role the interaction of ICP27 and Aly/REF plays during infection, these residues were mutated to alanine, and a recombinant virus, WRL-A, was constructed. Virus production was reduced about 10-fold during WRL-A infection, and export of ICP27 protein and most viral mRNAs was less efficient. We conclude that interaction of ICP27 with Aly/REF contributes to efficient viral mRNA export.

  11. Intracellular accumulation dynamics and fate of zinc ions in alveolar epithelial cells exposed to airborne ZnO nanoparticles at the air–liquid interface

    SciTech Connect

    Mihai, Cosmin; Chrisler, William B.; Xie, Yumei; Hu, Dehong; Szymanski, Craig J.; Tolic, Ana; Klein, Jessica A.; Smith, Jordan N.; Tarasevich, Barbara J.; Orr, Galya

    2013-12-02

    Airborne nanoparticles (NPs) that enter the respiratory tract are likely to reach the alveolar region. Accumulating observations support a role for zinc oxide (ZnO) NP dissolution in toxicity, but the majority of in vitro studies were conducted in cells exposed to NPs in growth media, where large doses of dissolved ions are shed into the exposure solution. To determine the precise intracellular accumulation dynamics and fate of zinc ions (Zn2+) shed by airborne NPs in the cellular environment, we exposed alveolar epithelial cells to aerosolized NPs at the air-liquid interface (ALI). Using a fluorescent indicator for Zn2+, together with organelle-specific fluorescent proteins, we quantified Zn2+ in single cells and organelles over time. We found that at the ALI, intracellular Zn2+ values peaked 3 h post exposure and decayed to normal values by 12 h, while in submersed cultures, intracellular Zn2+ values continued to increase over time. The lowest toxic NP dose at the ALI generated peak intracellular Zn2+ values that were nearly 3 folds lower than the peak values generated by the lowest toxic dose of NPs in submersed cultures, and 8 folds lower than the peak values generated by the lowest toxic dose of ZnSO4 or Zn2+. At the ALI, the majority of intracellular Zn2+ was found in endosomes and lysosomes as early as 1 h post exposure. In contrast, the majority of intracellular Zn2+ following exposures to ZnSO4 was found in other larger vesicles, with less than 10% in endosomes and lysosomes. In conclusion, together, our observations indicate that low but critical levels of intracellular Zn2+ have to be reached, concentrated specifically in endosomes and lysosomes, for toxicity to occur, and point to the focal dissolution of the NPs in the cellular environment and the accumulation of the ions specifically in endosomes and lysosomes as the processes

  12. Intracellular accumulation dynamics and fate of zinc ions in alveolar epithelial cells exposed to airborne ZnO nanoparticles at the air–liquid interface

    DOE PAGES

    Mihai, Cosmin; Chrisler, William B.; Xie, Yumei; ...

    2013-12-02

    Airborne nanoparticles (NPs) that enter the respiratory tract are likely to reach the alveolar region. Accumulating observations support a role for zinc oxide (ZnO) NP dissolution in toxicity, but the majority of in vitro studies were conducted in cells exposed to NPs in growth media, where large doses of dissolved ions are shed into the exposure solution. To determine the precise intracellular accumulation dynamics and fate of zinc ions (Zn2+) shed by airborne NPs in the cellular environment, we exposed alveolar epithelial cells to aerosolized NPs at the air-liquid interface (ALI). Using a fluorescent indicator for Zn2+, together with organelle-specificmore » fluorescent proteins, we quantified Zn2+ in single cells and organelles over time. We found that at the ALI, intracellular Zn2+ values peaked 3 h post exposure and decayed to normal values by 12 h, while in submersed cultures, intracellular Zn2+ values continued to increase over time. The lowest toxic NP dose at the ALI generated peak intracellular Zn2+ values that were nearly 3 folds lower than the peak values generated by the lowest toxic dose of NPs in submersed cultures, and 8 folds lower than the peak values generated by the lowest toxic dose of ZnSO4 or Zn2+. At the ALI, the majority of intracellular Zn2+ was found in endosomes and lysosomes as early as 1 h post exposure. In contrast, the majority of intracellular Zn2+ following exposures to ZnSO4 was found in other larger vesicles, with less than 10% in endosomes and lysosomes. In conclusion, together, our observations indicate that low but critical levels of intracellular Zn2+ have to be reached, concentrated specifically in endosomes and lysosomes, for toxicity to occur, and point to the focal dissolution of the NPs in the cellular environment and the accumulation of the ions specifically in endosomes and lysosomes as the processes underlying the potent toxicity of airborne ZnO NPs.« less

  13. Caractérisation électrique des interfaces P^+-Si-poly/N-c-Si réalisées par dépôt LPCVD de films fortement dopés in~situ au bore

    NASA Astrophysics Data System (ADS)

    Akani, M.; Benouis, C. E.; Benzohra, M.

    1993-08-01

    Diodes with polycrystalline in situ boron doped emitter deposited by LPCVD on N doped monocrystalline silicon wafers have been analysed electrically with the aim to identify the conduction mechanism through the jonction. In this paper we present the I(V,T) and C (V, T) measurements of the diodes annealed at 1 050 °C during 11 min 45 s in oxygen, argon and nitrogen atmosphere. We also compare the non annealed diode data previously found with our present results, and try to correlate the electrical measurements to the structural analysis [1]. We conclude that the dominant mechanism shows the electrical quality of the studied structures. Des diodes à émetteur polycristallin dopé in situ au bore et déposé par LPCVD sur des plaquettes de silicium monocristallin dopé N sont analysées électriquement dans le but d'identifier les mécanismes de conduction à travers la jonction. Nous présentons les résultats des mesures I (V, T) et C (V, T) des diodes recuites (processées) à 1 050 °C pendant 11 min 45 s dans des atmosphères d'oxygène, d'argon et d'azote et les comparons aux résultats des diodes non recuites. Nous essayons de corréler les résultats des mesures électriques aux analyses de structure réalisées par ailleurs [1]. L'identification du mécanisme de transport prépondérant témoignera de la qualité électrique des structures étudiées.

  14. FAMoS - an information service on the usage of data files in AliEn

    NASA Astrophysics Data System (ADS)

    Abramyan, A.; Betev, L.; Buncic, P.; Grigoras, C.; Grigoryan, A.; Manukyan, N.; Pedreira, M. M.; Saiz, P.

    2015-05-01

    The File Access Monitoring Service (FAMoS) leverages the information stored in the central AliEn file catalogue, which describes every file in a Unix-like directory structure, as well as metadata on file location and its replicas. In addition, it uses the access information provided by a set of API servers, used by all Grid clients to access the catalogue. The main functions of FAMoS are to sort the file accesses by logical groups, access time, user and storage element. The collected data identifies rarely used groups of files, as well as those with high popularity over different time periods. This information can be further used to optimize file distribution and replication factors, thus increasing the data processing efficiency. The paper describes the FAMoS structure and user interface and presents the results obtained in one year of service operation.

  15. Phenotypic and physiologic variability in nasal epithelium cultured from smokers and non-smokers exposed to secondhand tobacco smoke

    EPA Science Inventory

    The emergence of air-liquid interface (ALI) culturing of mammalian airway epithelium is a recent innovation for experimental modeling of airway epithelial development, function, and pathogenic mechanisms associated with infectious agent and irritant exposure. This construct provi...

  16. Predictive criteria to study the pathogenesis of malaria-associated ALI/ARDS in mice.

    PubMed

    Ortolan, Luana S; Sercundes, Michelle K; Barboza, Renato; Debone, Daniela; Murillo, Oscar; Hagen, Stefano C F; Russo, Momtchilo; D' Império Lima, Maria Regina; Alvarez, José M; Amaku, Marcos; Marinho, Claudio R F; Epiphanio, Sabrina

    2014-01-01

    Malaria-associated acute lung injury/acute respiratory distress syndrome (ALI/ARDS) often results in morbidity and mortality. Murine models to study malaria-associated ALI/ARDS have been described; we still lack a method of distinguishing which mice will develop ALI/ARDS before death. This work aimed to characterize malaria-associated ALI/ARDS in a murine model and to demonstrate the first method to predict whether mice are suffering from ALI/ARDS before death. DBA/2 mice infected with Plasmodium berghei ANKA developing ALI/ARDS or hyperparasitemia (HP) were compared using histopathology, PaO2 measurement, pulmonary X-ray, breathing capacity, lung permeability, and serum vascular endothelial growth factor (VEGF) levels according to either the day of death or the suggested predictive criteria. We proposed a model to predict malaria-associated ALI/ARDS using breathing patterns (enhanced pause and frequency respiration) and parasitemia as predictive criteria from mice whose cause of death was known to retrospectively diagnose the sacrificed mice as likely to die of ALI/ARDS as early as 7 days after infection. Using this method, we showed increased VEGF levels and increased lung permeability in mice predicted to die of ALI/ARDS. This proposed method for accurately identifying mice suffering from ALI/ARDS before death will enable the use of this model to study the pathogenesis of this disease.

  17. Predictive Criteria to Study the Pathogenesis of Malaria-Associated ALI/ARDS in Mice

    PubMed Central

    Ortolan, Luana S.; Sercundes, Michelle K.; Debone, Daniela; Hagen, Stefano C. F.; D' Império Lima, Maria Regina; Alvarez, José M.; Marinho, Claudio R. F.; Epiphanio, Sabrina

    2014-01-01

    Malaria-associated acute lung injury/acute respiratory distress syndrome (ALI/ARDS) often results in morbidity and mortality. Murine models to study malaria-associated ALI/ARDS have been described; we still lack a method of distinguishing which mice will develop ALI/ARDS before death. This work aimed to characterize malaria-associated ALI/ARDS in a murine model and to demonstrate the first method to predict whether mice are suffering from ALI/ARDS before death. DBA/2 mice infected with Plasmodium berghei ANKA developing ALI/ARDS or hyperparasitemia (HP) were compared using histopathology, PaO2 measurement, pulmonary X-ray, breathing capacity, lung permeability, and serum vascular endothelial growth factor (VEGF) levels according to either the day of death or the suggested predictive criteria. We proposed a model to predict malaria-associated ALI/ARDS using breathing patterns (enhanced pause and frequency respiration) and parasitemia as predictive criteria from mice whose cause of death was known to retrospectively diagnose the sacrificed mice as likely to die of ALI/ARDS as early as 7 days after infection. Using this method, we showed increased VEGF levels and increased lung permeability in mice predicted to die of ALI/ARDS. This proposed method for accurately identifying mice suffering from ALI/ARDS before death will enable the use of this model to study the pathogenesis of this disease. PMID:25276057

  18. Association of Heme Oxygenase 1 with Lung Protection in Malaria-Associated ALI/ARDS

    PubMed Central

    Pereira, Marcelo L. M.; Ortolan, Luana S.; Sercundes, Michelle K.; Debone, Daniela; Murillo, Oscar; Lima, Flávia A.

    2016-01-01

    Malaria is a serious disease, caused by the parasite of the genus Plasmodium, which was responsible for 440,000 deaths in 2015. Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is one of the main clinical complications in severe malaria. The murine model DBA/2 reproduces the clinical signs of ALI/ARDS in humans, when infected with Plasmodium berghei ANKA. High levels of HO-1 were reported in cases of severe malaria. Our data indicated that the HO-1 mRNA and protein expression are increased in mice that develop malaria-associated ALI/ARDS (MA-ALI/ARDS). Additionally, the hemin, a HO-1 inducing drug, prevented mice from developing MA-ALI/ARDS when administered prior to the development of MA-ALI/ARDS in this model. Also, hemin treatment showed an amelioration of respiratory parameters in mice, high VEGF levels in the sera, and a decrease in vascular permeability in the lung, which are signs of ALI/ARDS. Therefore, the induction of HO-1 before the development of MA-ALI/ARDS could be protective. However, the increased expression of HO-1 on the onset of MA-ALI/ARDS development may represent an effort to revert the phenotype of this syndrome by the host. We therefore confirm that HO-1 inducing drugs could be used for prevention of MA-ALI/ARDS in humans. PMID:27974865

  19. Optical Turbulence Characterization by WRF model above Ali, Tibet

    NASA Astrophysics Data System (ADS)

    Wang, Hongshuai; Yao, Yongqiang; Liu, Liyong; Qian, Xuan; Yin, Jia

    2015-04-01

    Atmospheric optical turbulence modeling and forecast for astronomy is a relatively recent discipline, but has played important roles in site survey, optimization of large telescope observing tables, and in the applications of adaptive optics technique. The numerical approach, by using of meteorological parameters and parameterization of optical turbulence, can provide all the optical turbulence parameters related, such as C2n profile, coherent length, wavefront coherent time, seeing, isoplanatic angle, and so on. This is particularly interesting for searching new sites without the long and expensive site testing campaigns with instruments. Earlier site survey results by the site survey team of National Astronomical Observatories of China imply that the south-west Tibet, Ali, is one of the world best IR and sub-mm site. For searching the best site in Ali area, numerical approach by Weather and Research Forecasting (WRF) model had been used to evaluate the climatology of the optical turbulence. The WRF model is configured over a domain 200km×200km with 1km horizontal resolution and 65 vertical levels from ground to the model top(10millibars) in 2010. The initial and boundary conditions for the model are provided by the 1° × 1° Global Final Analysis data from NCEP. The distribution and seasonal variation of optical turbulence parameters over this area are presented.

  20. Critical Evaluation of Air-Liquid Interface Cell Exposure Systems for in Vitro Assessment of Atmospheric Pollutants

    EPA Science Inventory

    We compared various in vitro exposure systems for their ability to expose cells to particles and gases. The systems tested use different mechanisms to deliver multi-pollutants to the cells: diffusion, sedimentation, thermophoresis (THP) and electrostatic precipitation (ESP). Vari...

  1. Intestinal epithelial culture under an air-liquid interface: a tool for studying human and mouse esophagi.

    PubMed

    Yokobori, T; Suzuki, S; Miyazaki, T; Sohda, M; Sakai, M; Tanaka, N; Ozawa, D; Hara, K; Honjo, H; Altan, B; Fukuchi, M; Ishii, H; Iwatsuki, M; Sugimachi, K; Sudo, T; Iwaya, T; Nishida, N; Mimori, K; Kuwano, H; Mori, M

    2016-10-01

    This study investigated whether an intestinal epithelial culture method can be applied to mouse and human esophageal cultures. The esophagi harvested from 1-day-old mice and adult humans were maintained in collagen gels. A commercially available culture medium for human embryonic stem cells was used for the human esophageal culture. We discovered that the intestinal epithelial culture method can be successfully applied to both mouse and human esophageal cultures. The long-term cultured esophageal organoids were rod-like luminal structures lined with myofibroblasts. We discovered that regeneration of the esophageal mucosal surface can be almost completely achieved in vitro, and the advantage of this method is that organoid cultures may be generated using host-derived fibroblasts as a niche. This method is a promising tool for mouse and human research in intestinal biology, carcinogenesis, and regenerative medicine.

  2. Experimental Results Obtained with Air Liquide Cold Compression System: CERN LHC and SNS Projects

    NASA Astrophysics Data System (ADS)

    Delcayre, F.; Courty, J.-C.; Hamber, F.; Hilbert, B.; Monneret, E.; Toia, J.-L.

    2006-04-01

    Large scale collider facilities will make intensive use of superconducting magnets, operating below 2.0 K. This dictates high-capacity refrigeration systems operating below 2.0 K. These systems, making use of cryogenic centrifugal compressors in a series arrangement with room temperature screw compressors will be coupled to a refrigerator, providing a certain power at 4.5 K. A first Air Liquide Cold Compression System (CCS) unit was built and delivered to CERN in 2001. Installed at the beginning of 2002, it was commissioned and tested successfully during year 2002. A series of four sets of identical CCS were then tested in 2004. Another set of four cryogenic centrifugal compressors (CCC) has been delivered to Thomas Jefferson National Accelerator Facility (JLAB) for the Spallation Neutron Source (SNS) in 2002. These compressors were tested and commissioned from December 2004 to July 2005. The experimental results obtained with these systems will be presented and discussed: the characteristics of the CCC will be detailed. The principles of control for the CCC in series will be detailed.

  3. Overview of Air Liquide refrigeration systems between 1.8 K and 200 K

    SciTech Connect

    Gondrand, C.; Durand, F.; Delcayre, F.; Crispel, S.; Baguer, G. M. Gistau

    2014-01-29

    Cryogenic refrigeration systems are necessary for numerous applications. Gas purification and distillation require temperatures between 15 K and 200 K depending on the application, space simulation chambers down to 15 K, superconductivity between 1.8 K and up to 75 K (magnets, cavities or HTS devices like cables, FCL, SMES, etc), Cold Neutron Sources between 15 and 20 K, etc. Air Liquide Advanced Technologies is designing and manufacturing refrigerators since 60 years to satisfy those needs. The step by step developments achieved have led to machines with higher efficiency and reliability. In 1965, reciprocating compressors and Joule Thomson expansion valves were used. In 1969, centripetal expanders began to be used. In 1980, oil lubricated screw compressors took the place of reciprocating compressors and a standard range of Claude cycle refrigerators was developed: the HELIAL series. 1980 was also the time for cryogenic centrifugal compressor development. In 2011, driven by the need for lower operational cost (high efficiency and low maintenance), cycle oil free centrifugal compressors on magnetic bearings were introduced instead of screw compressors. The power extracted by centripetal expanders was recovered. Based on this technology, a range of Turbo-Brayton refrigerators has been designed for temperatures between 40 K and 150 K. On-going development will enable widening the range of Turbo-Brayton refrigerators to cryogenic temperatures down to 15 K.. Cryogenic centrifugal circulators have been developed in order to answer to an increasing demand of 4 K refrigerators able to distribute cold power.

  4. Overview of Air Liquide refrigeration systems between 1.8 K and 200 K

    NASA Astrophysics Data System (ADS)

    Gondrand, C.; Durand, F.; Delcayre, F.; Crispel, S.; Baguer, G. M. Gistau

    2014-01-01

    Cryogenic refrigeration systems are necessary for numerous applications. Gas purification and distillation require temperatures between 15 K and 200 K depending on the application, space simulation chambers down to 15 K, superconductivity between 1.8 K and up to 75 K (magnets, cavities or HTS devices like cables, FCL, SMES, etc), Cold Neutron Sources between 15 and 20 K, etc. Air Liquide Advanced Technologies is designing and manufacturing refrigerators since 60 years to satisfy those needs. The step by step developments achieved have led to machines with higher efficiency and reliability. In 1965, reciprocating compressors and Joule Thomson expansion valves were used. In 1969, centripetal expanders began to be used. In 1980, oil lubricated screw compressors took the place of reciprocating compressors and a standard range of Claude cycle refrigerators was developed: the HELIAL series. 1980 was also the time for cryogenic centrifugal compressor development. In 2011, driven by the need for lower operational cost (high efficiency and low maintenance), cycle oil free centrifugal compressors on magnetic bearings were introduced instead of screw compressors. The power extracted by centripetal expanders was recovered. Based on this technology, a range of Turbo-Brayton refrigerators has been designed for temperatures between 40 K and 150 K. On-going development will enable widening the range of Turbo-Brayton refrigerators to cryogenic temperatures down to 15 K.. Cryogenic centrifugal circulators have been developed in order to answer to an increasing demand of 4 K refrigerators able to distribute cold power.

  5. FLO11 expression and lipid biosynthesis are required for air-liquid biofilm formation in a Saccharomyces cerevisiae flor strain.

    PubMed

    Zara, Giacomo; Goffrini, Paola; Lodi, Tiziana; Zara, Severino; Mannazzu, Ilaria; Budroni, Marilena

    2012-11-01

    Air-liquid biofilm formation is largely dependent on Flo11p and seems related to cell lipid content and composition. Here, it is shown that in the presence of cerulenin, a known inhibitor of the fatty acid synthase complex, biofilm formation is inhibited together with FLO11 transcription in a flor strain of Saccharomyces cerevisiae, while the administration of saturated fatty acids to cerulenin-containing medium restores biofilm formation and FLO11 transcription. It is also shown that, in biofilm cells, the FLO11 transcription is accompanied by the transcription of ACC1, ACS1 and INO1 key genes in lipid biosynthesis and that biofilm formation is affected by the lack of inositol in flor medium. These results are compatible with the hypothesis that the air-liquid biofilm formation depends on FLO11 transcription levels as well as on fatty acids biosynthesis.

  6. Advances in the Lightweight Air-Liquid Composite Heat Exchanger Development for Space Exploration Applications

    NASA Technical Reports Server (NTRS)

    Shin, E. Eugene; Johnston, J. Chris; Haas, Daniel

    2011-01-01

    An advanced, lightweight composite modular Air/Liquid (A/L) Heat Exchanger (HX) Prototype for potential space exploration thermal management applications was successfully designed, manufactured, and tested. This full-scale Prototype consisting of 19 modules, based on recommendations from its predecessor Engineering Development unit (EDU) but with improved thermal characteristics and manufacturability, was 11.2 % lighter than the EDU and achieves potentially a 42.7% weight reduction from the existing state-of-the-art metallic HX demonstrator. However, its higher pressure drop (0.58 psid vs. 0.16 psid of the metal HX) has to be mitigated by foam material optimizations and design modifications including a more systematic air channel design. Scalability of the Prototype design was validated experimentally by comparing manufacturability and performance between the 2-module coupon and the 19-module Prototype. The Prototype utilized the thermally conductive open-cell carbon foam material but with lower density and adopted a novel high-efficiency cooling system with significantly increased heat transfer contact surface areas, improved fabricability and manufacturability compared to the EDU. Even though the Prototype was required to meet both the thermal and the structural specifications, accomplishing the thermal requirement was a higher priority goal for this first version. Overall, the Prototype outperformed both the EDU and the corresponding metal HX, particularly in terms of specific heat transfer, but achieved 93.4% of the target. The next generation Prototype to achieve the specification target, 3,450W would need 24 core modules based on the simple scaling factor. The scale-up Prototype will weigh about 14.7 Kg vs. 21.6 Kg for the metal counterpart. The advancement of this lightweight composite HX development from the original feasibility test coupons to EDU to Prototype is discussed in this paper.

  7. Muhammad Ali's Fighting Words: The Paradox of Violence in Nonviolent Rhetoric

    ERIC Educational Resources Information Center

    Gorsevski, Ellen W.; Butterworth, Michael L.

    2011-01-01

    While Muhammad Ali has been the subject of countless articles and books written by sports historians and journalists, rhetorical scholars have largely ignored him. This oversight is surprising given both the tradition of social movement scholarship within rhetorical studies and Ali's influential eloquence as a world renowned celebrity espousing…

  8. Biomarkers of ALI/ARDS: pathogenesis, discovery, and relevance to clinical trials.

    PubMed

    Janz, David R; Ware, Lorraine B

    2013-08-01

    Despite the high incidence and poor prognosis of acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS), it remains challenging to identify patients who are at highest risk of developing these syndromes, differentiate these syndromes from other causes of acute respiratory failure, and accurately prognosticate once the diagnosis is made. The identification and validation of biological markers of ALI has the potential to ameliorate these challenges by facilitating studies of therapies aimed at prevention, identifying patients more accurately that have ALI so they can benefit from evidence-based therapies and enrollment in clinical trials, and determining which patients are unlikely to have a positive outcome to guide therapeutic choices and trials of experimental rescue therapies. This article reviews the current state of biomarker research in ALI/ARDS. New methodologies for identification of novel biomarkers of ALI, including metabolomics, proteomics, gene expression, and genetic studies are also discussed.

  9. The development of the hand-held dual-sensor ALIS

    NASA Astrophysics Data System (ADS)

    Sato, Motoyuki; Fujiwara, Jun; Takahashi, Kazunori

    2007-04-01

    Since 2002, we have developed a new hand-held land mine detection dual-sensor ALIS. ALIS is equipped with a metal detector and a GPR, and it has a sensor tracking system, which can record the GPR and Metal detector signal with its location. It makes possible to process the data afterwards, including migration. The migration processing drastically increases the quality of the image of the buried objects. The new system, we do not need any standard mark on the ground. Also, ALIS uses two different GPOR systems, including VNA (Vector Network Analyzer) based GPR and an Impulse GPR. VNA based GPR can provide better quality GPR images, although the impulse GPR is faster and light weight. ALIS evaluation tests were held in mine affected courtiers including Afghanistan, Croatia, Egypt and Cambodia. In the two-month evaluation test in Cambodia, ALIS worked without any problem. After some demonstrations and evaluation, we got many useful suggestions. Using these advises, we have modified the ALIS and it is now more easy to use. ALIS will be commercialized in 2007.

  10. Dynamic virtual AliEn Grid sites on Nimbus with CernVM

    NASA Astrophysics Data System (ADS)

    Harutyunyan, A.; Buncic, P.; Freeman, T.; Keahey, K.

    2010-04-01

    We describe the work on enabling one click deployment of Grid sites of AliEn Grid framework on the Nimbus 'science cloud' at the University of Chicago. The integration of computing resources of the cloud with the resource pool of AliEn Grid is achieved by leveraging two mechanisms: the Nimbus Context Broker developed at Argonne National Laboratory and the University of Chicago, and CernVM - a baseline virtual software appliance for LHC experiments developed at CERN. Two approaches of dynamic virtual AliEn Grid site deployment are presented.

  11. Dispersion of Particles on Fluid-Liquid Interfaces

    NASA Astrophysics Data System (ADS)

    Dalal, B.; Gurupatham, S.; Hossain, M.; Fischer, I.; Singh, P.; Joseph, D.

    2011-11-01

    This talk is concerned with the dispersion of particles on the fluid-liquid interface. In our previous studies we have shown that when small particles, e.g., flour, pollen, etc., come in contact with an air-liquid interface, they disperse in a manner that appears explosive. This is due to the fact that the capillary force pulls particles into the interface causing them to accelerate to a relatively-large velocity. The motion of particles in the direction normal to the interface is inertia dominated, and so they oscillate vertically about the equilibrium position before coming to a stop under viscous drag. This causes a radially-outward lateral flow on the interface that causes nearby particles to move away. In experiments the strength of the lateral flow was measured using tracer particles that were placed on the interface for this purpose. The dispersion on a liquid-liquid interface was relatively weaker than on an air-liquid interface, and occurred over a longer period of time. This partly was a consequence of the fact that particles became separated while sedimenting through the upper liquid and reached the interface over a time interval that lasted for several seconds. The rate of dispersion depended on the size of particles, the particle and liquids densities, the viscosities of the liquids involved, and the contact angle.

  12. Hand-held dual-sensor ALIS and its evaluation tests

    NASA Astrophysics Data System (ADS)

    Sato, Motoyuki; Takahashi, Kazunori

    2008-04-01

    Since 2002, our research group at Tohoku University has developed a new hand-held land mine detection dual-sensor ALIS. ALIS is equipped with a metal detector and a GPR, and it has a sensor tracking system, which can record the GPR and Metal detector signal with its location. It makes possible to process the data afterwards, including migration. The migration processing drastically increases the quality of the image of the buried objects. ALIS evaluation test was conducted in Croatia in October 2007. Then after, we stared a half-year evaluation test of ALIS in QC test in Croatia in December 2007. This test will be conducted in various soil and environmental conditions in Croatia.

  13. Air–liquid interface enhances oxidative phosphorylation in intestinal epithelial cell line IPEC-J2

    PubMed Central

    Klasvogt, Sonja; Zuschratter, Werner; Schmidt, Anke; Kröber, Andrea; Vorwerk, Sandra; Wolter, Romina; Isermann, Berend; Wimmers, Klaus; Rothkötter, Hermann-Josef; Nossol, Constanze

    2017-01-01

    The intestinal porcine epithelial cell line IPEC-J2, cultured under the air–liquid interface (ALI) conditions, develops remarkable morphological characteristics close to intestinal epithelial cells in vivo. Improved oxygen availability has been hypothesised to be the leading cause of this morphological differentiation. We assessed oxygen availability in ALI cultures and examined the influence of this cell culture method on glycolysis and oxidative phosphorylation in IPEC-J2 using the submerged membrane culture (SMC) and ALI cultures. Furthermore, the role of HIF-1 as mediator of oxygen availability was analysed. Measurements of oxygen tension confirmed increased oxygen availability at the medium–cell interface and demonstrated reduced oxygen extraction at the basal compartment in ALI. Microarray analysis to determine changes in the genetic profile of IPEC-J2 in ALI identified 2751 modified transcripts. Further examinations of candidate genes revealed reduced levels of glycolytic enzymes hexokinase II and GAPDH, as well as lactate transporting monocarboxylate transporter 1 in ALI, whereas expression of the glucose transporter GLUT1 remained unchanged. Cytochrome c oxidase (COX) subunit 5B protein analysis was increased in ALI, although mRNA level remained at constant level. COX activity was assessed using photometric quantification and a three-fold increase was found in ALI. Quantification of glucose and lactate concentrations in cell culture medium revealed significantly reduced glucose levels and decreased lactate production in ALI. In order to evaluate energy metabolism, we measured cellular adenosine triphosphate (ATP) aggregation in homogenised cell suspensions showing similar levels. However, application of the uncoupling agent FCCP reduced ATP levels in ALI but not in SMC. In addition, HIF showed reduced mRNA levels in ALI. Furthermore, HIF-1α protein was reduced in the nuclear compartment of ALI when compared to SCM as confirmed by confocal microscopy

  14. Relocalization of nuclear ALY proteins to the cytoplasm by the tomato bushy stunt virus P19 pathogenicity protein.

    PubMed

    Uhrig, Joachim F; Canto, Tomas; Marshall, David; MacFarlane, Stuart A

    2004-08-01

    The P19 protein of tomato bushy stunt virus (TBSV) is a multifunctional pathogenicity determinant involved in suppression of posttranscriptional gene silencing, virus movement, and symptom induction. Here, we report that P19 interacts with the conserved RNA-binding domain of an as yet uncharacterized family of plant ALY proteins that, in animals, are involved in export of RNAs from the nucleus and transcriptional coactivation. We show that the four ALY proteins encoded by the Arabidopsis genome and two ALY proteins from Nicotiana benthamiana are localized to the nucleus. Moreover, and in contrast to animal ALY, all but one of the proteins are also in the nucleolus, with distinct subnuclear localizations. Infection of plants by TBSV or expression of P19 from Agrobacterium results in relocation of three of the six ALY proteins from the nucleus to the cytoplasm demonstrating specific targeting of the ALY proteins by P19. The differential effects on subcellular localization indicate that, in plants, the various ALY proteins may have different functions. Interaction with and relocalization of ALY is prevented by mutation of P19 at residues previously shown to be important for P19 function in plants. Down-regulation of expression of two N. benthamiana ALY genes by virus-induced gene silencing did not interfere with posttranscriptional gene silencing. Targeting of ALY proteins during TBSV infection may therefore be related to functions of P19 in addition to its silencing suppression activity.

  15. Aly/ REF, a factor for mRNA transport, activates RH gene promoter function.

    PubMed

    Suganuma, Hiroshi; Kumada, Maki; Omi, Toshinori; Gotoh, Takaya; Lkhagvasuren, Munkhtulga; Okuda, Hiroshi; Kamesaki, Toyomi; Kajii, Eiji; Iwamoto, Sadahiko

    2005-06-01

    The rhesus (Rh) blood group antigens are of considerable importance in transfusion medicine as well as in newborn or autoimmune hemolytic diseases due to their high antigenicity. We identified a major DNaseI hypersensitive site at the 5' flanking regions of both RHD and RHCE exon 1. A 34 bp fragment located at -191 to -158 from a translation start position, and containing the TCCCCTCCC sequence, was involved in enhancing promoter activity, which was assessed by luciferase reporter gene assay. A biotin-labelled 34 bp probe isolated an mRNA transporter protein, Aly/REF. The specific binding of Aly/REF to RH promoter in erythroid was confirmed by chromatin immunoprecipitation assay. The silencing of Aly/REF by siRNA reduced not only the RH promoter activity of the reporter gene but also transcription from the native genome. These facts provide second proof of Aly/REF as a transcription coactivator, initially identified as a coactivator for the TCRalpha enhancer function. Aly/REF might be a novel transcription cofactor for erythroid-specific genes.

  16. Preliminary studies on the extraction of Glycospanonins in Tongkat Ali extract

    NASA Astrophysics Data System (ADS)

    Abirame, S.; Sivakumar, K.; Chua, L. S.; Sarmidi, M. R.

    2016-06-01

    Eurycoma longifolia, locally known as Tongkat Ali, is a famous medicinal plant in the family of Simaroubaceae and well known for its aphrodisiac properties from its water extract. The root of E. longifolia is used to extract wide range bioactive components of Tongkat Ali. Previous works standardised Tongkat Ali extracts by measuring the concentration of eurycomanone, a quassinoid marker chemical, within the overall extract. There is a newer Malaysian standard that specifies that Tongkat Ali can be standardised to glycosaponin, thus it is desired to determine how extraction parameters such as particle size, extraction temperature, and solvent type affects the glycosaponin content in the extract. The overall study is aimed to determine how the extraction parameters affect the glycosaponin amount in extract. This paper presents the preliminary work where in this study the effect of particle size on overall extract and glycosaponin quantification method development is presented. A reflux extraction method was used to extract Tongkat Ali with a particle size of 0.5 mm, 1.0 mm and 2.0 mm of raw material to study effect of particle size on overall extract. Water and methanol were the two types of solvent used for extraction to study the quantity of glycosaponin.

  17. ALIS (Auroral Large Imaging System) used for optical observations of the meteor impact process

    NASA Astrophysics Data System (ADS)

    Brändström, U.; Gustavsson, B.; Steen, A.; Pellinen-Wannberg, Asta

    2001-11-01

    This paper outlines a possibly new use of the Auroral Large Imaging System (ALIS) for studies of differential ablation phenomena in meteor trails. By simultaneous imaging from up to six stations, the altitude distribution of the meteor trails could be triangulated, while some stations simultaneously image the trails in for example the sodium (5893 Å) and calcium (4227 Å) lines. ALIS was primarily designed for auroral studies, but has also been used for studies of heater-induced airglow, polar stratospheric clouds as well as other phenomena. The system consits of six unmanned remote-controlled observation stations located in northern Sweden.

  18. Mechanism and early intervention research on ALI during emergence surgery of Stanford type-A AAD

    PubMed Central

    Cheng, Yi; Jin, Mu; Dong, Xiuhua; Sun, Lizhong; Liu, Jing; Wang, Rong; Yang, Yanwei; Lin, Peirong; Hou, Siyu; Ma, Yuehua; Wang, Yuefeng; Pan, Xudong; Lu, Jiakai; Cheng, Weiping

    2016-01-01

    Abstract Background: Stanford type-A acute aortic dissection (AAD) is a severe cardiovascular disease demonstrating the characteristics of acute onset and rapid development, with high morbidity and mortality. The available evidence shows that preoperative acute lung injury (ALI) induced by Stanford type-A AAD is a frequent and important cause for a number of untoward consequences. However, there is no study assessing the incidence of preoperative ALI and its independent determinants before Standford type-A AAD surgery in Chinese adult patients. Methods/design: This is a prospective, double-blind, signal-center clinical trial. We will recruit 130 adult patients undergoing Stanford type-A AAD surgery. The incidence of preoperative ALI will be evaluated. Perioperative clinical baselines and serum variables including coagulation, fibrinolysis, inflammatory, reactive oxygen species, and endothelial cell function will be assayed. The independent factors affecting the occurrence of preoperative ALI will be identified by multiple logistic regression analysis. Trial registration: ClinicalTrials.gov (https://register.clinicaltrials.gov/), Registration number NCT01894334. PMID:27759648

  19. Cross calibration of the Landsat-7 ETM+ and EO-1 ALI sensor

    USGS Publications Warehouse

    Chander, G.; Meyer, D.J.; Helder, D.L.

    2004-01-01

    As part of the Earth Observer 1 (EO-1) Mission, the Advanced Land Imager (ALI) demonstrates a potential technological direction for Landsat Data Continuity Missions. To evaluate ALI's capabilities in this role, a cross-calibration methodology has been developed using image pairs from the Landsat-7 (L7) Enhanced Thematic Mapper Plus (ETM+) and EO-1 (ALI) to verify the radiometric calibration of ALI with respect to the well-calibrated L7 ETM+ sensor. Results have been obtained using two different approaches. The first approach involves calibration of nearly simultaneous surface observations based on image statistics from areas observed simultaneously by the two sensors. The second approach uses vicarious calibration techniques to compare the predicted top-of-atmosphere radiance derived from ground reference data collected during the overpass to the measured radiance obtained from the sensor. The results indicate that the relative sensor chip assemblies gains agree with the ETM+ visible and near-infrared bands to within 2% and the shortwave infrared bands to within 4%.

  20. The evaluation test of hand-held dual-sensor ALIS in Croatia and Cambodia

    NASA Astrophysics Data System (ADS)

    Sato, Motoyuki; Takahashi, Kazunori

    2007-04-01

    We are developing a new hand-held land mine detection dual-sensor (ALIS) which is equipped with a metal detector and a GPR. ALIS is equipped with a sensor tracking system, which can record the GPR and Metal detector signal with its location. It makes possible to process the data after the data was acquired, including migration. The migration processing drastically increases the quality of the images of the buried objects. Evaluation test of ALIS has been conducted in several test sites. In February 2006, a one-month evaluation test was conducted in Croatia, and in October- December 2006, a two-month evaluation test was conducted in Croatia. Since the dual-sensor is a new landmine detection sensor, and the conventional evaluation procedure developed for metal detectors cannot directly be applied for the dual sensor. In Croatia, the detection probability was comparable to that by a metal detector operated by local deminers. In addition, we showed that ALIS provides image of buried objects by GPR, which can be used for identification. Therefore, their performances were sufficiently high. Then the test was also conducted in Cambodia. The test was carried out by 2 local deminers independently, which allows studying the influence of different operators and increases the statistical value of the results.

  1. Deployment of dual-sensor ALIS for humanitarian demining in Cambodia

    NASA Astrophysics Data System (ADS)

    Sato, M.; Takahashi, K.

    2013-06-01

    We are in the process of developing a high-resolution landmine scanning system "ALIS" which produces horizontal slices of the shallow subsurface for visualization of buried explosives and inert clutter. As many AP mines contain minimum amounts of metal, metal detectors need to be combined with a complimentary subsurface imaging sensor. Ground Penetrating Radar (GPR) is widely accepted for subsurface sensing in the fields of geology, archaeology and utility detection. The demining application requires real-time imaging results with centimetre resolution in a highly portable package. The key requirement for sharp images of the subsurface is the precise tracking of the geophysical sensor(s) during data collection. We should also notice that GPR system is a very wide band radar system, and equivalent to UWB radar, which has recently been developed for short-range high-accuracy radar. We are testing simplified but effective signal processing for imaging mines. We are currently testing a dual sensor ALIS which is a realtime sensor tracking system based on a CCD camera and image processing. In this paper we introduce the GPR systems which we have developed for detection of buried antipersonnel mines and small size explosives. ALIS has been deployed in Cambodia since 2009 and detected more than 70 mines in mine fields, and returned more than 13ha cleaned fields to local farmers. We also report the current status of ALIS in Cambodia.

  2. Traumatic forequarter amputation associated acute lung injury (ALI): report of one case.

    PubMed

    Liang, K; Gan, X; Deng, Z

    2012-07-01

    One case of traumatic forequarter amputation associated acute lung injury (ALI) was presented. A discussion reviewing the treatment guidelines for this devastating injury, and pointing out the importance of supporting the lung and preventing the development of acute respiratory distress syndrome (ARDS) was included.

  3. 76 FR 62494 - Designation of Ibrahim `Awwad Ibrahim `Ali al-Badri, Also Known as Dr. Ibrahim `Awwad Ibrahim...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Designation of Ibrahim `Awwad Ibrahim `Ali al-Badri, Also Known as Dr. Ibrahim `Awwad Ibrahim `Ali al-Badri, Also Known as Ibrahim `Awad Ibrahim al-Badri al-Samarrai, Also Known as Ibrahim Awwad Ibrahim al-Samarra'I, Also Known as Dr. Ibrahim Awwad...

  4. A comparison between HfO2/Al2O3 nano-laminates and ternary HfxAlyO compound as the dielectric material in InGaAs based metal-oxide-semiconductor (MOS) capacitors

    NASA Astrophysics Data System (ADS)

    Krylov, Igor; Pokroy, Boaz; Eizenberg, Moshe; Ritter, Dan

    2016-09-01

    We compare the electrical properties of HfO2/Al2O3 nano-laminates with those of the ternary HfxAlyO compound in metal oxide semiconductor (MOS) capacitors. The dielectrics were deposited by atomic layer deposition on InGaAs. Water, ozone, and oxygen plasma were tested as oxygen precursors, and best results were obtained using water. The total dielectric thickness was kept constant in our experiments. It was found that the effective dielectric constant increased and the leakage current decreased with the number of periods. Best results were obtained for the ternary compound. The effect of the sublayer thicknesses on the electrical properties of the interface was carefully investigated, as well as the role of post-metallization annealing. Possible explanations for the observed trends are provided. We conclude that the ternary HfxAlyO compound is more favorable than the nano-laminates approach for InGaAs based MOS transistor applications.

  5. Simultaneous quantitation of six major quassinoids in Tongkat Ali dietary supplements by liquid chromatography with tandem mass spectrometry.

    PubMed

    Han, Young Min; Jang, Moonhee; Kim, In Sook; Kim, Seung Hyun; Yoo, Hye Hyun

    2015-07-01

    Tongkat Ali (Eurycoma longifolia) is one of the most popular traditional herbs in Southeast Asia and generally consumed as forms of dietary supplements, tea, or drink additives for coffee or energy beverages. In this study, the liquid chromatography with tandem mass spectrometry method for the simultaneous quantitation of six major quassinoids of Tongkat Ali (eurycomanone, 13,21-dihydroeurycomanone, 13α(21)-epoxyeurycomanone, 14,15β-dihydroxyklaineanone, eurycomalactone, and longilactone) was developed and validated. Using the developed method, the content of the six quassinoids was measured in Tongkat Ali containing dietary supplement tablets or capsules, and the resulting data were used to confirm the presence of Tongkat Ali in those products. Among the six quassinoids, eurycomanone was the most abundant quassinoid in all samples tested. The developed method would be useful for the quality assessment of Tongkat Ali containing dietary supplements.

  6. ASTER, ALI and Hyperion sensors data for lithological mapping and ore minerals exploration.

    PubMed

    Beiranvand Pour, Amin; Hashim, Mazlan

    2014-01-01

    This paper provides a review of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Advanced Land Imager (ALI), and Hyperion data and applications of the data as a tool for ore minerals exploration, lithological and structural mapping. Spectral information extraction from ASTER, ALI, and Hyperion data has great ability to assist geologists in all disciplines to map the distribution and detect the rock units exposed at the earth's surface. The near coincidence of Earth Observing System (EOS)/Terra and Earth Observing One (EO-1) platforms allows acquiring ASTER, ALI, and Hyperion imagery of the same ground areas, resulting accurate information for geological mapping applications especially in the reconnaissance stages of hydrothermal copper and gold exploration, chromite, magnetite, massive sulfide and uranium ore deposits, mineral components of soils and structural interpretation at both regional and district scales. Shortwave length infrared and thermal infrared bands of ASTER have sufficient spectral resolution to map fundamental absorptions of hydroxyl mineral groups and silica and carbonate minerals for regional mapping purposes. Ferric-iron bearing minerals can be discriminated using six unique wavelength bands of ALI spanning the visible and near infrared. Hyperion visible and near infrared bands (0.4 to 1.0 μm) and shortwave infrared bands (0.9 to 2.5 μm) allowed to produce image maps of iron oxide minerals, hydroxyl-bearing minerals, sulfates and carbonates in association with hydrothermal alteration assemblages, respectively. The techniques and achievements reviewed in the present paper can further introduce the efficacy of ASTER, ALI, and Hyperion data for future mineral and lithological mapping and exploration of the porphyry copper, epithermal gold, chromite, magnetite, massive sulfide and uranium ore deposits especially in arid and semi-arid territory.

  7. Involvement of CD4⁺ Foxp3⁺ regulatory T cells in persistence of Leishmania donovani in the liver of alymphoplastic aly/aly mice.

    PubMed

    Tiwananthagorn, Saruda; Iwabuchi, Kazuya; Ato, Manabu; Sakurai, Tatsuya; Kato, Hirotomo; Katakura, Ken

    2012-01-01

    Visceral leishmaniasis (VL) is a chronic and fatal disease in humans and dogs caused by the intracellular protozoan parasites, Leishmania donovani and L. infantum (L. chagasi). Relapse of disease is frequent in immunocompromised patients, in which the number of VL cases has been increasing recently. The present study is aimed to improve the understanding of mechanisms of L. donovani persistence in immunocompromised conditions using alymphoplastic aly/aly mice. Hepatic parasite burden, granuloma formation and induction of regulatory T cells were determined for up to 7 months after the intravenous inoculation with L. donovani promastigotes. While control aly/+ mice showed a peak of hepatic parasite growth at 4 weeks post infection (WPI) and resolved the infection by 8 WPI, aly/aly mice showed a similar peak in hepatic parasite burden but maintained persistent in the chronic phase of infection, which was associated with delayed and impaired granuloma maturation. Although hepatic CD4(+)Foxp3(+) but not CD8(+)Foxp3(+) T cells were first detected at 4 WPI in both strains of mice, the number of CD4(+)Foxp3(+) T cells was significantly increased in aly/aly mice from 8 WPI. Immunohistochemical analysis demonstrated the presence of Foxp3(+) T cells in L. donovani-induced hepatic granulomas and perivascular neo-lymphoid aggregates. Quantitative real-time PCR analysis of mature granulomas collected by laser microdissection revealed the correlation of Foxp3 and IL-10 mRNA level. Furthermore, treatment of infected aly/aly mice with anti-CD25 or anti-FR4 mAb resulted in significant reductions in both hepatic Foxp3(+) cells and parasite burden. Thus, we provide the first evidence that CD4(+)Foxp3(+) Tregs mediate L. donovani persistence in the liver during VL in immunodeficient murine model, a result that will help to establish new strategies of immunotherapy against this intracellular protozoan pathogen.

  8. Towards active microfluidics: Interface turbulence in thin liquid films with floating molecular machines

    NASA Astrophysics Data System (ADS)

    Alonso, Sergio; Mikhailov, Alexander S.

    2009-06-01

    Thin liquid films with floating active protein machines are considered. Cyclic mechanical motions within the machines, representing microscopic swimmers, lead to molecular propulsion forces applied to the air-liquid interface. We show that when the rate of energy supply to the machines exceeds a threshold, the flat interface becomes linearly unstable. As a result of this instability, the regime of interface turbulence, characterized by irregular traveling waves and propagating machine clusters, is established. Numerical investigations of this nonlinear regime are performed. Conditions for the experimental observation of the instability are discussed.

  9. An intravascular MRI contrast agent based on Gd(DO3A-Lys) for tumor angiography.

    PubMed

    Yang, Chang-Tong; Chandrasekharan, Prashant; He, Tao; Poh, Zihan; Raju, Anandhkumar; Chuang, Kai-Hsiang; Robins, Edward G

    2014-01-01

    An intravascular MRI contrast agent Gd(DO3A-Lys), Gadolinium(III) (2,2',2″-(10-(3-(5-benzamido-6-methoxy-6-oxohexylamino)-3-oxopropyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetate), has been studied for tumor angiography based on its high relaxivity and long blood half-life. The preparation procedures of the contrast agent have been modified in order to achieve higher yield and improve the synthetic reproducibility. High relaxivity of Gd(DO3A-Lys) has been confirmed by measurements at 3 T, 7 T and 9.4 T magnetic fields. The relaxivity-dependent albumin binding study indicated that Gd(DO3A-Lys) partially bound to albumin protein. In vitro cell viability in HK2 cell indicated low cytotoxicity of Gd(DO3A-Lys) up to 1.2 mM [Gd] concentration. In vivo toxicity studies demonstrated no toxicity of Gd(DO3A-Lys) on kidney tissues up to 0.2 mM [Gd]. While the toxicity on liver tissue was not observed at low dosage (1.0 mM [Gd]), Gd(DO3A-Lys) cause certain damage on hepatic tissue at high dosage (2.0 mM [Gd]). The DO3A-Lys has been labeled with (68)Ga radioisotope for biodistribution studies. (68)Ga(DO3A-Lys) has high uptake in both HT1080 and U87MG xenograft tumors, and has high accumulation in blood. Contrast-enhanced MR angiography (CE-MRA) in mice bearing U87MG xenograft tumor demonstrated that Gd(DO3A-Lys) could enhance vascular microenvironment around the tumor, and displays promising characteristics of an MRI contrast agent for tumor angiography.

  10. Plant proteins, minerals and trace elements of Eurycoma longifolia (Tongkat Ali).

    PubMed

    Chua, Lee Suan; Abdul-Rahman, Nurulaini; Rosidi, Bustanur; Lee, Chew Tin

    2013-03-01

    A water extraction method has been used to extract plant proteins from the roots of Eurycoma longifolia harvested from Perak and Pahang, Malaysia. On the basis of the spectroscopic Bradford assay, Tongkat Ali Perak and Pahang contained 0.3868 and 0.9573 mg mL(-1) of crude protein, respectively. The crude proteins were separated by one dimensional 15% sodium dodecyl sulphate polyacrylamide gel electrophoresis into two (49.8 and 5.5 kD) and four (49.8, 24.7, 21.1 and 5.5 kD) protein spots for Tongkat Ali Perak and Pahang, respectively. Isoleucine was present in the highest concentration significantly. Both plant samples showed differences in the mineral and trace element profiles, but the minerals calcium, magnesium and potassium were present in the highest concentration. The highly concerned toxic metals such as arsenic and lead were not detected.

  11. Tongkat Ali (Eurycoma longifolia Jack): a review on its ethnobotany and pharmacological importance.

    PubMed

    Bhat, Rajeev; Karim, A A

    2010-10-01

    Eurycoma longifolia Jack is an herbal medicinal plant of South-East Asian origin, popularly recognized as 'Tongkat Ali.' The plant parts have been traditionally used for its antimalarial, aphrodisiac, anti-diabetic, antimicrobial and anti-pyretic activities, which have also been proved scientifically. The plant parts are rich in various bioactive compounds (like eurycomaoside, eurycolactone, eurycomalactone, eurycomanone, and pasakbumin-B) among which the alkaloids and quassinoids form a major portion. Even though toxicity and safety evaluation studies have been pursued, still a major gap exists in providing scientific base for commercial utilization and clearance of the Tongkat Ali products with regard to consumer's safety. The present review aims at reviewing the research works undertaken till date, on this plant in order to provide sufficient baseline information for future works and for commercial exploitation.

  12. Stress field during early magmatism in the Ali Sabieh Dome, Djibouti, SE Afar rift

    NASA Astrophysics Data System (ADS)

    Sue, Christian; Le Gall, Bernard; Daoud, Ahmed Mohamed

    2014-09-01

    The so-called Ali Sabieh range, SE Afar rift, exhibits an atypical antiform structure occurring in the overall extensional tectonic context of the Afar triple junction. We dynamically analyzed the brittle deformation of this specific structural high using four different methods in order to better constrain the tectonic evolution of this key-area in the Afar depression. Paleostress inversions appear highly consistent using the four methods, which a posteriori validates this approach. Computed paleostress fields document two major signals: an early E-W extensional field, and a later transcurrent field, kinematically consistent with the previous one. The Ali Sabieh range may have evolved continuously during Oligo-Miocene times from large-scale extensional to transcurrent tectonism, as the result of probable local stress permutation between σ1 and σ2 stress axes.

  13. Securing the AliEn File Catalogue - Enforcing authorization with accountable file operations

    NASA Astrophysics Data System (ADS)

    Schreiner, Steffen; Bagnasco, Stefano; Sankar Banerjee, Subho; Betev, Latchezar; Carminati, Federico; Vladimirovna Datskova, Olga; Furano, Fabrizio; Grigoras, Alina; Grigoras, Costin; Mendez Lorenzo, Patricia; Peters, Andreas Joachim; Saiz, Pablo; Zhu, Jianlin

    2011-12-01

    The AliEn Grid Services, as operated by the ALICE Collaboration in its global physics analysis grid framework, is based on a central File Catalogue together with a distributed set of storage systems and the possibility to register links to external data resources. This paper describes several identified vulnerabilities in the AliEn File Catalogue access protocol regarding fraud and unauthorized file alteration and presents a more secure and revised design: a new mechanism, called LFN Booking Table, is introduced in order to keep track of access authorization in the transient state of files entering or leaving the File Catalogue. Due to a simplification of the original Access Envelope mechanism for xrootd-protocol-based storage systems, fundamental computational improvements of the mechanism were achieved as well as an up to 50% reduction of the credential's size. By extending the access protocol with signed status messages from the underlying storage system, the File Catalogue receives trusted information about a file's size and checksum and the protocol is no longer dependent on client trust. Altogether, the revised design complies with atomic and consistent transactions and allows for accountable, authentic, and traceable file operations. This paper describes these changes as part and beyond the development of AliEn version 2.19.

  14. Comparison of EO1 Landsat-7 ETM+ and EO-1 ALI images over Rochester, New York

    NASA Astrophysics Data System (ADS)

    Pedelty, Jeffrey A.; Morisette, Jeffrey T.; Smith, James A.

    2002-08-01

    We present a comparison of images from the ETM+ sensor on Landsat-7 and the ALI instrument on EO-1 over a test site in Rochester, NY. The site contains a variety of features, ranging from water of varying depths, deciduous/coniferous forest, grass fields, to urban areas. The nearly coincident cloud-free images were collected just one minute apart on 25 August, 2001. We atmospherically corrected each image with the 6S atmosphere model, using aerosol optical thickness and water vapor column density measured by a Cimel sun photometer within the Aerosol Robotic Network (Aeronet), along with ozone density derived from NCEP data. We present three-color composites from each instrument that show excellent qualitative agreement. We present ETM+ and ALI reflectance spectra for water, grass, and urban targets. We make a more detailed comparison for our forest site, where we use measured geometric and optical properties as input to the SAIL canopy reflectance model, which we compare to the ETM+, ALI, and EO-1 Hyperion reflectance spectra.

  15. Interfaces Select Specific Stereochemical Conformations: The Isomerization of Glyoxal at the Liquid Water Interface.

    PubMed

    Zhu, Chongqin; Kais, Sabre; Zeng, Xiao Cheng; Francisco, Joseph S; Gladich, Ivan

    2017-01-11

    Interfacial chemistry involving glyoxal at aerosol surfaces is postulated to catalyze aerosol growth. This chemistry remains speculative due to a lack of detailed information concerning the physicochemical behavior of glyoxal at the interface of atmospheric aerosols. Here, we report results from high-level electronic structure calculations as well as both classical and Born-Oppenheimer ab initio molecular dynamics simulations of glyoxal solvation at the air/liquid water interface. When compared to the gas phase, the trans to cis isomerization of glyoxal at the liquid water interface is found to be catalyzed; additionally, the trans conformation is selectively solvated within the bulk to a greater degree than is the cis conformation. These two processes, i.e., the catalytic effect at the water interface and the differentially selective solvation, act to enhance the concentration of the cis isomer of glyoxal at the water interface. This has important consequences for the interpretation of experiments and for the modeling of glyoxal chemistry both at the interface of water clouds and at aerosols. Broader implications of this work relate to describing the role of interfaces in selecting specific stereo molecular structures at interfacial environments.

  16. Bacillus anthracis spores germinate extracellularly at air-liquid interface in an in vitro lung model under serum-free conditions

    DOE PAGES

    Powell, Joshua D.; Hutchison, Janine R.; Hess, Becky M.; ...

    2015-07-30

    Aims: To better understand the parameters that govern spore dissemination after lung exposure using in vitro cell systems. Methods and Results: We evaluated the kinetics of uptake, germination and proliferation of B. anthracis Sterne spores in association with human primary lung epithelial cells, Calu-3, and A549 cell lines. We also analyzed the influence of various cell culture media formulations related to spore germination. Conclusions: We found negligible spore uptake by epithelial cells, but germination and proliferation of spores in the extracellular environment was evident, and was appreciably higher in A549 and Calu-3 cultures than in primary epithelial cells. Additionally, ourmore » results revealed spores in association with primary cells submerged in cell culture media germinated 1 h« less

  17. Bacillus anthracis spores germinate extracellularly at air-liquid interface in an in vitro lung model under serum-free conditions

    SciTech Connect

    Powell, Joshua D.; Hutchison, Janine R.; Hess, Becky M.; Straub, Tim M.

    2015-07-30

    Aims: To better understand the parameters that govern spore dissemination after lung exposure using in vitro cell systems. Methods and Results: We evaluated the kinetics of uptake, germination and proliferation of B. anthracis Sterne spores in association with human primary lung epithelial cells, Calu-3, and A549 cell lines. We also analyzed the influence of various cell culture media formulations related to spore germination. Conclusions: We found negligible spore uptake by epithelial cells, but germination and proliferation of spores in the extracellular environment was evident, and was appreciably higher in A549 and Calu-3 cultures than in primary epithelial cells. Additionally, our results revealed spores in association with primary cells submerged in cell culture media germinated 1 h

  18. Emissions of NH3, CO2 and H2S during swine wastewater management: Characterization of transient emissions after air-liquid interface disturbances

    NASA Astrophysics Data System (ADS)

    Blanes-Vidal, V.; Guàrdia, M.; Dai, X. R.; Nadimi, E. S.

    2012-07-01

    Air contaminants emitted from stored animal wastewater affect human health and the environment. Measurements of gaseous emissions from undisturbed animal wastewater are abundant in the literature. However, in-barn wastewater management is characterized by the frequent occurrence of surface liquid disturbances. Information about emissions during and after wastewater disturbances is scarce. This study evaluates emissions of NH3, CO2 and H2S under transient conditions after wastewater disturbances (caused by slurry addition, water addition and mixing), and describes the mechanisms involved until reaching steady-state conditions. All three disturbances modified the gas emission patterns. Emissions of NH3 immediately decreased after the disturbances (-61% after slurry and water addition and by -91% after mixing), and then gradually increased during 90-200 min. Emissions of CO2 increased during the disturbances (40% during slurry and water addition and 1515% during mixing), and then decreased during up to 30 min after the disturbance. H2S emissions sharply increased during all three disturbances and then decreased for 2 min to 20 min. Emissions under transient conditions were related to the formation of a pH profile. Transient emissions should be considered in gas emission studies as they may represent an important part of the cumulative gas emissions during slurry storage.

  19. Respiratory Impairment after Early Red Cell Transfusion in Pediatric Patients with ALI/ARDS.

    PubMed

    Rajasekaran, Surender; Sanfilippo, Dominic; Shoemaker, Allen; Curtis, Scott; Zuiderveen, Sandra; Ndika, Akunne; Stoiko, Michael; Hassan, Nabil

    2012-01-01

    Introduction. In the first 48 hours of ventilating patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), a multipronged approach including packed red blood cell (PRBC) transfusion is undertaken to maintain oxygen delivery. Hypothesis. We hypothesized children with ALI/ARDS transfused within 48 hours of initiating mechanical ventilation would have worse outcome. The course of 34 transfused patients was retrospectively compared to 45 nontransfused control patients admitted to the PICU at Helen DeVos Children's Hospital between January 1st 2008 and December 31st 2009. Results. Mean hemoglobin (Hb) prior to transfusion was 8.2 g/dl compared to 10.1 g/dl in control. P/F ratio decreased from 135.4 ± 7.5 to 116.5 ± 8.8 in transfused but increased from 148.0 ± 8.0 to 190.4 ± 17.8 (P < 0.001) in control. OI increased in the transfused from 11.7 ± 0.9 to 18.7 ± 1.6 but not in control. Ventilator days in the transfused were 15.6 ± 1.7 versus 9.5 ± 0.6 days in control (P < 0.001). There was a trend towards higher rates of MODS in transfused patients; 29.4% versus 17.7%, odds ratio 1.92, 95% CI; 0.6-5.6 Fisher exact P < 0.282. Conclusion. This study suggests that early transfusions of patients with ALI/ARDS were associated with increased ventilatory needs.

  20. Respiratory Impairment after Early Red Cell Transfusion in Pediatric Patients with ALI/ARDS

    PubMed Central

    Rajasekaran, Surender; Sanfilippo, Dominic; Shoemaker, Allen; Curtis, Scott; Zuiderveen, Sandra; Ndika, Akunne; Stoiko, Michael; Hassan, Nabil

    2012-01-01

    Introduction. In the first 48 hours of ventilating patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), a multipronged approach including packed red blood cell (PRBC) transfusion is undertaken to maintain oxygen delivery. Hypothesis. We hypothesized children with ALI/ARDS transfused within 48 hours of initiating mechanical ventilation would have worse outcome. The course of 34 transfused patients was retrospectively compared to 45 nontransfused control patients admitted to the PICU at Helen DeVos Children's Hospital between January 1st 2008 and December 31st 2009. Results. Mean hemoglobin (Hb) prior to transfusion was 8.2 g/dl compared to 10.1 g/dl in control. P/F ratio decreased from 135.4 ± 7.5 to 116.5 ± 8.8 in transfused but increased from 148.0 ± 8.0 to 190.4 ± 17.8 (P < 0.001) in control. OI increased in the transfused from 11.7 ± 0.9 to 18.7 ± 1.6 but not in control. Ventilator days in the transfused were 15.6 ± 1.7 versus 9.5 ± 0.6 days in control (P < 0.001). There was a trend towards higher rates of MODS in transfused patients; 29.4% versus 17.7%, odds ratio 1.92, 95% CI; 0.6–5.6 Fisher exact P < 0.282. Conclusion. This study suggests that early transfusions of patients with ALI/ARDS were associated with increased ventilatory needs. PMID:22957223

  1. Summary of Current Radiometric Calibration Coefficients for Landsat MSS, TM, ETM+, and EO-1 ALI Sensors

    NASA Technical Reports Server (NTRS)

    Chander, Gyanesh; Markham, Brian L.; Helder, Dennis L.

    2009-01-01

    This paper provides a summary of the current equations and rescaling factors for converting calibrated Digital Numbers (DNs) to absolute units of at-sensor spectral radiance, Top-Of- Atmosphere (TOA) reflectance, and at-sensor brightness temperature. It tabulates the necessary constants for the Multispectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+), and Advanced Land Imager (ALI) sensors. These conversions provide a basis for standardized comparison of data in a single scene or between images acquired on different dates or by different sensors. This paper forms a needed guide for Landsat data users who now have access to the entire Landsat archive at no cost.

  2. The Persian legend of ophthalmology: Ali Asghar Khodadoust and his everlasting lines.

    PubMed

    Sajjadi, Sepideh; Fesharaki, Hamid; Abtahi, Zahra-Alsadat; Murray, Richard T; Fereidan-Esfahani, Mahboobeh; Mazloumi, Mehdi; Abtahi, Seyed-Hossein

    2013-06-01

    This is a brief celebratory overview of the fruitful life and scientific endeavors of Professor Ali Asghar Khodadoust (b.1935), a world renowned ophthalmologist, Persian icon of modern ophthalmology and an international pioneer of eye research. The global reputation of Dr. Khodadoust is rooted in his extensive studies on corneal diseases and transplantation biology. As a result of his truly deserved world renown, several famous American ophthalmologists have recognized him as the world's best corneal graft surgeon. Due to his exceptionally impressive achievements in this field, a clinical finding has been named in his honor, the "Khodadoust rejection line", a sign indicative of a chronic focal transplant reaction.

  3. Summary of current radiometric calibration coefficients for Landsat MSS, TM, ETM+, and EO-1 ALI sensors

    USGS Publications Warehouse

    Chander, G.; Markham, B.L.; Helder, D.L.

    2009-01-01

    This paper provides a summary of the current equations and rescaling factors for converting calibrated Digital Numbers (DNs) to absolute units of at-sensor spectral radiance, Top-Of-Atmosphere (TOA) reflectance, and at-sensor brightness temperature. It tabulates the necessary constants for the Multispectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+), and Advanced Land Imager (ALI) sensors. These conversions provide a basis for standardized comparison of data in a single scene or between images acquired on different dates or by different sensors. This paper forms a needed guide for Landsat data users who now have access to the entire Landsat archive at no cost.

  4. Simulation of EO-1 Hyperion Data from ALI Multispectral Data Based on the Spectral Reconstruction Approach.

    PubMed

    Liu, Bo; Zhang, Lifu; Zhang, Xia; Zhang, Bing; Tong, Qingxi

    2009-01-01

    Data simulation is widely used in remote sensing to produce imagery for a new sensor in the design stage, for scale issues of some special applications, or for testing of novel algorithms. Hyperspectral data could provide more abundant information than traditional multispectral data and thus greatly extend the range of remote sensing applications. Unfortunately, hyperspectral data are much more difficult and expensive to acquire and were not available prior to the development of operational hyperspectral instruments, while large amounts of accumulated multispectral data have been collected around the world over the past several decades. Therefore, it is reasonable to examine means of using these multispectral data to simulate or construct hyperspectral data, especially in situations where hyperspectral data are necessary but hard to acquire. Here, a method based on spectral reconstruction is proposed to simulate hyperspectral data (Hyperion data) from multispectral Advanced Land Imager data (ALI data). This method involves extraction of the inherent information of source data and reassignment to newly simulated data. A total of 106 bands of Hyperion data were simulated from ALI data covering the same area. To evaluate this method, we compare the simulated and original Hyperion data by visual interpretation, statistical comparison, and classification. The results generally showed good performance of this method and indicated that most bands were well simulated, and the information both preserved and presented well. This makes it possible to simulate hyperspectral data from multispectral data for testing the performance of algorithms, extend the use of multispectral data and help the design of a virtual sensor.

  5. Effect of Tongkat Ali on stress hormones and psychological mood state in moderately stressed subjects

    PubMed Central

    2013-01-01

    Background Eurycoma longifolia is a medicinal plant commonly called tongkat ali (TA) and “Malaysian ginseng.” TA roots are a traditional “anti-aging” remedy and modern supplements are intended to improve libido, energy, sports performance and weight loss. Previous studies have shown properly-standardized TA to stimulate release of free testosterone, improve sex drive, reduce fatigue, and improve well-being. Methods We assessed stress hormones and mood state in 63 subjects (32 men and 31 women) screened for moderate stress and supplemented with a standardized hot-water extract of TA root (TA) or Placebo (PL) for 4 weeks. Analysis of variance (ANOVA) with significance set at p < 0.05 was used to determine differences between groups. Results Significant improvements were found in the TA group for Tension (−11%), Anger (−12%), and Confusion (−15%). Stress hormone profile (salivary cortisol and testosterone) was significantly improved by TA supplementation, with reduced cortisol exposure (−16%) and increased testosterone status (+37%). Conclusion These results indicate that daily supplementation with tongkat ali root extract improves stress hormone profile and certain mood state parameters, suggesting that this “ancient” remedy may be an effective approach to shielding the body from the detrimental effects of “modern” chronic stress, which may include general day-to-day stress, as well as the stress of dieting, sleep deprivation, and exercise training. PMID:23705671

  6. Magma-driven antiform structures in the Afar rift: The Ali Sabieh range, Djibouti

    NASA Astrophysics Data System (ADS)

    Le Gall, Bernard; Daoud, Mohamed Ahmed; Maury, René C.; Rolet, Joël; Guillou, Hervé; Sue, Christian

    2010-06-01

    The Ali Sabieh Range, SE Afar, is an antiform involving Mesozoic sedimentary rocks and synrift volcanics. Previous studies have postulated a tectonic origin for this structure, in either a contractional or extensional regime. New stratigraphic, mapping and structural data demonstrate that large-scale doming took place at an early stage of rifting, in response to a mafic laccolithic intrusion dated between 28 and 20 Ma from new K-Ar age determinations. Our 'laccolith' model is chiefly supported by: (i) the geometry of the intrusion roof, (ii) the recognition of roof pendants in its axial part, and (iii) the mapping relationships between the intrusion, the associated dyke-sill network, and the upper volcanic/volcaniclastic sequences. The laccolith is assumed to have inflated with time, and to have upwardly bent its sedimentary roof rocks. From the architecture of the ˜1 km-thick Mesozoic overburden sequences, ca. 2 km of roof lifting are assumed to have occurred, probably in association with reactivated transverse discontinuities. Computed paleostress tensors indicate that the minimum principal stress axis is consistently horizontal and oriented E-W, with a dominance of extensional versus strike-slip regimes. The Ali Sabieh laccolith is the first regional-scale magma-driven antiform structure reported so far in the Afro-Arabian rift system.

  7. STS-45 Earth observation of the Persian Gulf and the island of Abu Ali

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-45 Earth observation taken aboard Atlantis, Orbiter Vehicle (OV) 104, is of the northern reaches of the Persian Gulf with the sunglint pattern centered on the Saudi Arabian island of Abu Ali. Bright features along the coast are thought to be deposits of oil, released from a terminal offshore of Kuwait during the recent Persian Gulf War. Further up the coast, in Kuwait, the black, oil-soaked desert surrounding the site of the oil well fires is clearly visible. View was taken from an altitude of 160 nautical miles with OV-104 located at 28 degrees north and 52.8 degrees east. During the STS-45 mission, an international survey team focused on oil contamination of the shallow-water habitants in the area north of Abu Ali Island. Crewmembers contacted the NOAA survey vessel, the R/V Mt. Mitchell, several times and photographed water color and sunglint within the study area and throughout the entire Persian Gulf. These photographic data are expected to aid the Persian Gulf researchers in

  8. Divergence of the gene aly in experimentally evolved cytoraces, the members of the nasuta-albomicans complex of Drosophila.

    PubMed

    Radhika, P N; Ramachandra, N B

    2014-08-01

    We generated cytoraces by crossing the chromosomal races (Drosophila nasuta nasuta and Drosophila nasuta albomicans) of the nasuta subgroup of Drosophila and maintained the offspring over many generations through sibling mating. These cytoraces, along with their parents, are members of the nasuta-albomicans complex of Drosophila. The gene always early (aly) is one of the rapidly evolving genes in the genus Drosophila and plays a central role in regulating meiosis. Here we examined the rate of molecular evolution of aly in cytoraces of Drosophila and demonstrated that the rate of substitutions amongst cytoraces is around eight times greater than their parents and even amongst species of subgenera. Thus, the presence of positive selection in the laboratory-derived cytoraces based on the analysis of the synonymous and nonsynonymous substitution rates of aly suggests the rapid evolution in cytoraces.

  9. Transcriptional PROFILING OF MUCOCILIARY DIFFERENTIATION IN HUMAN AIRWAY EPITHELIAL CELLS

    EPA Science Inventory

    When cultured at an air-liquid interface (ALI) in the appropriate medium, primary human airway epithelial cells form a polarized, pseudostratified epithelium composed of ciliated and mucus-secreting cells. This culture system provides a useful tool for the in vitro study of...

  10. Land cover mapping with emphasis to burnt area delineation using co-orbital ALI and Landsat TM imagery

    NASA Astrophysics Data System (ADS)

    Petropoulos, George P.; Kontoes, Charalambos C.; Keramitsoglou, Iphigenia

    2012-08-01

    In this study, the potential of EO-1 Advanced Land Imager (ALI) radiometer for land cover and especially burnt area mapping from a single image analysis is investigated. Co-orbital imagery from the Landsat Thematic Mapper (TM) was also utilised for comparison purposes. Both images were acquired shortly after the suppression of a fire occurred during the summer of 2009 North-East of Athens, the capital of Greece. The Maximum Likelihood (ML), Artificial Neural Networks (ANNs) and Support Vector Machines (SVMs) classifiers were parameterised and subsequently applied to the acquired satellite datasets. Evaluation of the land use/cover mapping accuracy was based on the error matrix statistics. Also, the McNemar test was used to evaluate the statistical significance of the differences between the approaches tested. Derived burnt area estimates were validated against the operationally deployed Services and Applications For Emergency Response (SAFER) Burnt Scar Mapping service. All classifiers applied to either ALI or TM imagery proved flexible enough to map land cover and also to extract the burnt area from other land surface types. The highest total classification accuracy and burnt area detection capability was returned from the application of SVMs to ALI data. This was due to the SVMs ability to identify an optimal separating hyperplane for best classes' separation that was able to better utilise ALI's advanced technological characteristics in comparison to those of TM sensor. This study is to our knowledge the first of its kind, effectively demonstrating the benefits of the combined application of SVMs to ALI data further implying that ALI technology may prove highly valuable in mapping burnt areas and land use/cover if it is incorporated into the development of Landsat 8 mission, planned to be launched in the coming years.

  11. First results of auroral tomography from ALIS-Japan multi-station observations in March, 1995

    NASA Astrophysics Data System (ADS)

    Aso, T.; Ejiri, M.; Urashima, A.; Miyaoka, H.; Steen, Å.; Brändström, U.; Gustavsson, B.

    1998-01-01

    Auroral tomography observations have been carried out in March, 1995, as a joint international campaign between Sweden and Japan. Three unmanned Swedish ALIS stations (Kiruna, Merasjärvi, Tjautjas) and two Japanese JICCD sites (Abisko, Nikkaluokta), geographically separated by about 50 km at higher latitudes, were operated to capture multi-station monochromatic tomography images at 557.7 nm wavelength using CCD cameras. All cameras were pointing to one of the predetermined directions to secure a common field of view. Several images of auroral arcs, mostly for the core region right above Kiruna, have synchronously been taken by the multi-station imaging system. Tomographic inversion analysis for four-point images was carried out using the algebraic reconstruction technique. Reconstructions of a curved arc and of a double arc system suggest promising application of this technique to the retrieval of three-dimensional auroral luminosity.

  12. Nanoemulsions obtained via bubble-bursting at a compound interface

    NASA Astrophysics Data System (ADS)

    Feng, Jie; Roché, Matthieu; Vigolo, Daniele; Arnaudov, Luben N.; Stoyanov, Simeon D.; Gurkov, Theodor D.; Tsutsumanova, Gichka G.; Stone, Howard A.

    2014-08-01

    Bursting of bubbles at an air/liquid interface is a familiar occurrence relevant to foam stability, cell cultures in bioreactors and ocean-atmosphere mass transfer. In the latter case, bubble-bursting leads to the dispersal of sea-water aerosols in the surrounding air. Here we show that bubbles bursting at a compound air/oil/water-with-surfactant interface can disperse submicrometre oil droplets in water. Dispersal results from the detachment of an oil spray from the bottom of the bubble towards water during bubble collapse. We provide evidence that droplet size is selected by physicochemical interactions between oil molecules and the surfactants rather than by hydrodynamics. We demonstrate the unrecognized role that this dispersal mechanism may play in the fate of the sea surface microlayer and of pollutant spills by dispersing petroleum in the water column. Finally, our system provides an energy-efficient route, with potential upscalability, for applications in drug delivery, food production and materials science.

  13. Ali Observatory in Tibet: a unique northern site for future CMB ground-based observations

    NASA Astrophysics Data System (ADS)

    Su, Meng

    2015-08-01

    Ground-based CMB observations have been performed at the South Pole and the Atacama desert in Chile. However, a significant fraction of the sky can not be observed from just these two sites. For a full sky coverage from the ground in the future, a northern site for CMB observation, in particular CMB polarization, is required. Besides the long-thought site in Greenland, the high altitude Tibet plateau provides another opportunity. I will describe the Ali Observatory in Tibet, located at N32°19', E80°01', as a potential site for ground-based CMB observations. The new site is located on almost 5100m mountain, near Gar town, where is an excellent site for both infrared and submillimeter observations. Study with the long-term database of ground weather stations and archival satellite data has been performed. The site has enough relative height on the plateau and is accessible by car. The Shiquanhe town is 40 mins away by driving, and a recently opened airport with 40 mins driving, the site also has road excess, electricity, and optical fiber with fast internet. Preliminary measurement of the Precipitable Water Vapor is ~one quarter less than 0.5mm per year and the long term monitoring is under development. In addition, surrounding higher sites are also available and could be further developed if necessary. Ali provides unique northern sky coverage and together with the South Pole and the Atacama desert, future CMB observations will be able to cover the full sky from ground.

  14. An evidence-based systematic review of tongkat ali (Eurycoma longifolia) by the Natural Standard Research Collaboration.

    PubMed

    Ulbricht, Catherine; Conquer, Julie; Flanagan, Kelly; Isaac, Richard; Rusie, Erica; Windsor, Regina C

    2013-03-01

    An evidence-based systematic review of tongkat ali (Eurycoma longifolia) by the Natural Standard Research Collaboration consolidates the safety and efficacy data available in the scientific literature using a validated, reproducible grading rationale. This article includes written and statistical analysis of clinical trials, plus a compilation of expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

  15. The ALI-ARMS Code for Modeling Atmospheric non-LTE Molecular Band Emissions: Current Status and Applications

    NASA Technical Reports Server (NTRS)

    Kutepov, A. A.; Feofilov, A. G.; Manuilova, R. O.; Yankovsky, V. A.; Rezac, L.; Pesnell, W. D.; Goldberg, R. A.

    2008-01-01

    The Accelerated Lambda Iteration (ALI) technique was developed in stellar astrophysics at the beginning of 1990s for solving the non-LTE radiative transfer problem in atomic lines and multiplets in stellar atmospheres. It was later successfully applied to modeling the non-LTE emissions and radiative cooling/heating in the vibrational-rotational bands of molecules in planetary atmospheres. Similar to the standard lambda iterations ALI operates with the matrices of minimal dimension. However, it provides higher convergence rate and stability due to removing from the iterating process the photons trapped in the optically thick line cores. In the current ALI-ARMS (ALI for Atmospheric Radiation and Molecular Spectra) code version additional acceleration of calculations is provided by utilizing the opacity distribution function (ODF) approach and "decoupling". The former allows replacing the band branches by single lines of special shape, whereas the latter treats non-linearity caused by strong near-resonant vibration-vibrational level coupling without additional linearizing the statistical equilibrium equations. Latest code application for the non-LTE diagnostics of the molecular band emissions of Earth's and Martian atmospheres as well as for the non-LTE IR cooling/heating calculations are discussed.

  16. Identification of Antifungal Substances of Lactobacillus sakei subsp. ALI033 and Antifungal Activity against Penicillium brevicompactum Strain FI02.

    PubMed

    Huh, Chang Ki; Hwang, Tae Yean

    2016-03-01

    This study was performed to investigate the antifungal substances and the antifungal activity against fungi of lactic acid bacteria (LAB) isolated from kimchi. LAB from kimchi in Imsil showed antifungal activity against Penicillium brevicompactum strain FI02. LAB LI031 was identified as Lactobacillus sakei subsp. Antifungal substances contained in L. sakei subsp. ALI033 culture media were unstable at high pH levels. Both, the control and proteinase K and protease treated samples showed clear zones, suggesting that the antifungal substances produced by ALI033 were non-protein substances unaffected by protesases. Both, the control and catalase showed clear zones, suggesting that the antifungal metabolite was not H2O2. The molecular weights of the antifungal substances were ≤3,000 Da. The organic acid content of crude antifungal substances produced by L. sakei subsp. ALI033 showed high concentrations of lactic acid (502.47 mg/100 g). Therefore, these results suggest that antifungal substance produced by L. sakei subsp. ALI033 is most likely due to its ability in producing organic acid.

  17. Identification of Antifungal Substances of Lactobacillus sakei subsp. ALI033 and Antifungal Activity against Penicillium brevicompactum Strain FI02

    PubMed Central

    Huh, Chang Ki; Hwang, Tae Yean

    2016-01-01

    This study was performed to investigate the antifungal substances and the antifungal activity against fungi of lactic acid bacteria (LAB) isolated from kimchi. LAB from kimchi in Imsil showed antifungal activity against Penicillium brevicompactum strain FI02. LAB LI031 was identified as Lactobacillus sakei subsp. Antifungal substances contained in L. sakei subsp. ALI033 culture media were unstable at high pH levels. Both, the control and proteinase K and protease treated samples showed clear zones, suggesting that the antifungal substances produced by ALI033 were non-protein substances unaffected by protesases. Both, the control and catalase showed clear zones, suggesting that the antifungal metabolite was not H2O2. The molecular weights of the antifungal substances were ≤3,000 Da. The organic acid content of crude antifungal substances produced by L. sakei subsp. ALI033 showed high concentrations of lactic acid (502.47 mg/100 g). Therefore, these results suggest that antifungal substance produced by L. sakei subsp. ALI033 is most likely due to its ability in producing organic acid. PMID:27069906

  18. An Approach to the Stories of Sabahattin Ali within the Context of Marxist Literary Aesthetics: The Conflict between Peasants and the Intelligentsia

    ERIC Educational Resources Information Center

    Yigit, Murat

    2016-01-01

    This study will try to read the stories of Sabahattin Ali, who has written various books in Turkish, within the context of Marxist literary aesthetics, assess the types and characters in the stories of Sabahattin Ali within that framework, and observe the social levels and the gaps between them based on the relationships between the two extreme…

  19. 40 CFR 721.9527 - Bis(1,2,2,6,6-pentamethyl-4-piperidin-4-ol) ester of cy-clo-ali-phatic spiroketal.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-4-ol) ester of cy-clo-ali-phatic spiroketal. 721.9527 Section 721.9527 Protection of Environment...-piperidin-4-ol) ester of cy-clo-ali-phatic spiroketal. (a) Chemical substance and significant new uses...-piperidin-4-ol) ester of cycloaliphatic spiroketal (PMN No. P-91-1361) is subject to reporting under...

  20. Lithospheric mantle evolution in the Afro-Arabian domain: Insights from Bir Ali mantle xenoliths (Yemen)

    NASA Astrophysics Data System (ADS)

    Sgualdo, P.; Aviado, K.; Beccaluva, L.; Bianchini, G.; Blichert-Toft, J.; Bryce, J. G.; Graham, D. W.; Natali, C.; Siena, F.

    2015-05-01

    Detailed petrological and geochemical investigations of an extensive sampling of mantle xenoliths from the Neogene-Quaternary Bir Ali diatreme (southern Yemen) indicate that the underlying lithospheric mantle consists predominantly of medium- to fine-grained (often foliated) spinel-peridotites (85-90%) and spinel-pyroxenites (10-15%) showing thermobarometric estimates in the P-T range of 0.9-2.0 GPa and 900-1150 °C. Peridotites, including lherzolites, harzburgites and dunites delineate continuous chemical, modal and mineralogical variations compatible with large extractions of basic melts occurring since the late Proterozoic (~ 2 Ga, according to Lu-Hf model ages). Pyroxenites may represent intrusions of subalkaline basic melts interacting and equilibrated with the host peridotite. Subsequent metasomatism has led to modal changes, with evidence of reaction patches and clinopyroxene and spinel destabilization, as well as formation of new phases (glass, amphibole and feldspar). These changes are accompanied by enrichment of the most incompatible elements and isotopic compositions. 143Nd/144Nd ranges from 0.51419 to 0.51209 (εNd from + 30.3 to - 10.5), 176Hf/177Hf from 0.28459 to 0.28239 (εHf from + 64.4 to - 13.6), and 208Pb/204Pb from 36.85 to 41.56, thus extending from the depleted mantle (DM) towards the enriched OIB mantle (EM and HIMU) components. 3He/4He (R/RA) ratios vary from 7.2 to 7.9 with He concentrations co-varying with the most incompatible element enrichment, in parallel with metasomatic effects. These metasomatic events, particularly effective in harzburgites and dunites, are attributable to the variable interaction with alkaline basic melts related to the general extensional and rifting regime affecting the East Africa-Arabian domain during the Cenozoic. In this respect, Bir Ali mantle xenoliths resemble those occurring along the Arabian margins and the East Africa Rift system, similarly affected by alkaline metasomatism, whereas they are

  1. A Review of Ferdous al-Hekma fil-Tibb by Ali ibn Raban Tabari

    PubMed Central

    Ardalan, Mohammadreza; Khodadoust, Kazem; Mostafidi, Elmira

    2015-01-01

    T Ferdous al-Hekma (Paradise of Wisdom) is one of the oldest medical texts in the Islamic world written in Arabic in 850 AD by Ali ibn Raban Tabari. He was a Persian physician who moved from Tabaristan (Mazandaran province of modern day Iran) to Samarra during the reign of the Abbasid Caliph al-Mutawakkil (847-861 AD). We studied the book of Ferdous al-Hekma fil-Tibb, in an attempt to comprehend its general outlook on diseases of different organs, their classifications and the associated signs and symptoms. The book is one of the earliest medical pandects of the period of translation, adaptation and expansion of knowledge in the Islamic world during the 9th century AD. Tabari was mainly influenced by Hippocrates, Galen and Aristotle, as well as his contemporaries Johanna ibn Massavieh and Hunayn ibn Ishaq. The book is written in thirty chapters in a total number of 308 subtitles. In each part there is an introduction to the symptomatology, followed by organ specific diseases and therapeutic recommendations. Symptoms and physical signs of different diseases are vividly described in Ferdous al-Hekma, and some of them are even understandable for contemporary medical students. PMID:27350863

  2. Remembering Ali Alpar's Early Work, and: Three Types of Neutron Stars?

    NASA Astrophysics Data System (ADS)

    van den Heuvel, E. P. J.

    2011-09-01

    Some memories of Ali Alpar and his early work are presented, with particular emphasis on his work on the origin of milliscond pulsars. After this, arguments are summarized, indicating the existence of three categories of neutron stars, with two different formation mechanisms: (i) A low-mass category ( M~1.25 +/- 0.05 solar masses), characterized by low kick velocities. These neutron stars most probably formed by electron-capture collapse in degenerate O-Ne-Mg cores of stars of initial masses between ~8 and ~11 solar masses. (ii) An intermediate-mass category (M~1.40 +/- 0.10 solar masses), characterized by high kick velocities. These stars formed by the collapse of the iron cores of stars with initial masses probably between ~11 and ~19 solar masses. (iii) A category of massive neutron stars (M >= 1.70 solar masses), also characterized by high space velocities, and formed by the collapse of the iron cores, in this case of stars with intial masses >19 solar mases.

  3. In vivo effects of Eurycoma longifolia Jack (Tongkat Ali) extract on reproductive functions in the rat.

    PubMed

    Solomon, M C; Erasmus, N; Henkel, R R

    2014-05-01

    An aqueous extract of Eurycoma longifolia (Tongkat Ali; TA) roots is traditionally used to enhance male sexuality. Because previous studies are limited to only few sperm parameters or testosterone concentration, this study investigated the in vivo effects of TA on body and organ weight as well as functional sperm parameters in terms of safety and efficacy in the management of male infertility. Forty-two male rats were divided into a control, low-dose (200 mg kg(-1) BW) and high-dose (800 mg kg(-1) BW) group (n = 14). Rats were force-fed for 14 days and then sacrificed. Total body and organ weights of the prostate, testes, epididymides, gastrocnemius muscle and the omentum were recorded. Moreover, testosterone concentration, sperm concentration, motility, velocity, vitality, acrosome reaction and mitochondrial membrane potential (MMP) were assessed. Whilst TA decreased BW by 5.7% (P = 0.0276) and omentum fat by 31.9% (P = 0.0496), no changes in organ weights were found for the prostate, testes and epididymides. Testosterone concentration increased by 30.2% (P = 0.0544). Muscle weight also increased, yet not significantly. Whilst sperm concentration, total and progressive motility and vitality increased significantly, MMP improved markedly (P = 0.0765) by 25.1%. Because no detrimental effect could be observed, TA appears safe for possible treatment of male infertility and ageing male problems.

  4. Effect of Eurycoma longifolia Jack (Tongkat ali) extract on human spermatozoa in vitro.

    PubMed

    Erasmus, N; Solomon, M C; Fortuin, K A; Henkel, R R

    2012-10-01

    Eurycoma longifolia (Tongkat ali; TA) is a Malaysian shrub used to treat various illnesses including male infertility. Considering that TA is used to improve male fertility and no report regarding its safety has been published, this study investigated the effects of TA extract on various sperm functions. Semen samples of 27 patients and 13 donors were divided into two groups, washed and swim-up spermatozoa, and incubated with different concentrations of TA (1, 10, 20, 100, 2000 μg ml(-1) ) for 1 h at 37 °C. A sample without addition of TA served as control. For washed spermatozoa, significant dose-dependent trends were found for vitality, total motility, acrosome reaction and reactive oxygen species-positive spermatozoa. However, these trends were only significant if the highest concentrations were included in the calculation. Contrary, the increase in the percentage of acrosome-reacted spermatozoa with increasing TA concentrations is very significant (P < 0.0001), and a significant difference (P = 0.0069) to the control could even be recorded at 20 μg TA per ml. For swim-up spermatozoa, no trend could be observed. Results indicate that the TA extract has no deleterious effects on sperm functions at therapeutically used concentrations (<2.5 μg ml(-1) ). However, at very high concentrations, TA may have harmful effects in vitro.

  5. Professor Mansour Ali Haseeb: Highlights from a pioneer of biomedical research, physician and scientist.

    PubMed

    Salih, Mustafa Abdalla M

    2013-01-01

    The article highlights the career of Professor Mansour Ali Haseeb (1910 - 1973; DKSM, Dip Bact, FRCPath, FRCP [Lond]), a pioneer worker in health, medical services, biomedical research and medical education in the Sudan. After his graduation from the Kitchener School of Medicine (renamed, Faculty of Medicine, University of Khartoum [U of K]) in 1934, he devoted his life for the development of laboratory medicine. He became the first Sudanese Director of Stack Medical Research Laboratories (1952 - 1962). He made valuable contributions by his services in the vaccine production and implementation programs, most notably in combating small pox, rabies and epidemic meningitis. In 1963 he became the first Sudanese Professor of Microbiology and Parasitology and served as the first Sudanese Dean of the Faculty of Medicine, U of K (1963-1969). He was an active loyal citizen in public life and served in various fields outside the medical profession. As Mayor of Omdurman, he was invited to visit Berlin in 1963 by Willy Brandt, Mayor of West Berlin (1957-1966) and Chancellor of the Federal Republic of Germany (1969 to 1974). Also as Mayor of Omdurman, he represented the City in welcoming Queen Elizabeth II during her visit to Sudan in February 1965. He also received State Medals from Egypt and Ethiopia. In 1973 he was appointed Chairman of the Sudan Medical Research Council, and was awarded the international Dr. Shousha Foundation Prize and Medal by the WHO for his contribution in the advancement of health, research and medical services.

  6. Air/Liquid-pressure and heartbeat-driven flexible fiber nanogenerators as a micro/nano-power source or diagnostic sensor.

    PubMed

    Li, Zetang; Wang, Zhong Lin

    2011-01-04

    We present a new approach for fabricating flexible fiber nanogenerators (FNGs) that can be used for smart shirts, flexible electronics, and medical applications. These FNGs are based on carbon fibers that are covered cylindrically by textured zinc oxide (ZnO) thin films. Once subjected to uni-compression by applying a pressure, the cylindrical ZnO thin film is under a compressive strain, resulting in a macroscopic piezopotential across its inner and exterior surfaces owing to the textured structure of the film, which is the driving force for generating an electric current in the external load. Using such a structure, an output peak voltage of 3.2 V and average current density of 0.15 μA cm(-2) are demonstrated. The FNGs rely on air pressure, so that it can work in a non-contact mode in cases of rotating tires, flowing air/liquid, and even in blood vessels. Pressure-driven FNGs added to a syringe show potential to harvest energy in blood vessels, gas pipes, and oil pipes, as long as there is a fluctuation in pressure (or turbulence). Heart-pulse driven FNGs can serve as ultrasensitive sensors for monitoring the behavior of the human heart, which may possibly be applied to medical diagnostics as sensors and measurement tools.

  7. Cellular Nuclear Export Factors TAP and Aly Are Required for HDAg-L-mediated Assembly of Hepatitis Delta Virus.

    PubMed

    Huang, Hsiu-Chen; Lee, Chung-Pei; Liu, Hui-Kang; Chang, Ming-Fu; Lai, Yu-Heng; Lee, Yu-Ching; Huang, Cheng

    2016-12-09

    Hepatitis delta virus (HDV) is a satellite virus of hepatitis B virus (HBV). HDV genome encodes two forms of hepatitis delta antigen (HDAg), small HDAg (HDAg-S), which is required for viral replication, and large HDAg (HDAg-L), which is essential for viral assembly. HDAg-L is identical to HDAg-S except that it bears a 19-amino acid extension at the C terminus. Both HDAgs contain a nuclear localization signal (NLS), but only HDAg-L contains a CRM1-independent nuclear export signal at its C terminus. The nuclear export activity of HDAg-L is important for HDV particle formation. However, the mechanisms of HDAg-L-mediated nuclear export of HDV ribonucleoprotein are not clear. In this study, the host cellular RNA export complex TAP-Aly was found to form a complex with HDAg-L, but not with an export-defective HDAg-L mutant, in which Pro(205) was replaced by Ala. HDAg-L was found to colocalize with TAP and Aly in the nucleus. The C-terminal domain of HDAg-L was shown to directly interact with the N terminus of TAP, whereas an HDAg-L mutant lacking the NLS failed to interact with full-length TAP. In addition, small hairpin RNA-mediated down-regulation of TAP or Aly reduced nuclear export of HDAg-L and assembly of HDV virions. Furthermore, a peptide, TAT-HDAg-L(198-210), containing the 10-amino acid TAT peptide and HDAg-L(198-210), inhibited the interaction between HDAg-L and TAP and blocked HDV virion assembly and secretion. These data demonstrate that formation and release of HDV particles are mediated by TAP and Aly.

  8. Mapping forest height, foliage height profiles and disturbance characteristics with time series of gap-filled Landsat and ALI imagery

    NASA Astrophysics Data System (ADS)

    Helmer, E.; Ruzycki, T. S.; Wunderle, J. M.; Kwit, C.; Ewert, D. N.; Voggesser, S. M.; Brandeis, T. J.

    2011-12-01

    We mapped tropical dry forest height (RMSE = 0.9 m, R2 = 0.84, range 0.6-7 m) and foliage height profiles with a time series of gap-filled Landsat and Advanced Land Imager (ALI) imagery for the island of Eleuthera, The Bahamas. We also mapped disturbance type and age with decision tree classification of the image time series. Having mapped these variables in the context of studies of wintering habitat of an endangered Nearctic-Neotropical migrant bird, the Kirtland's Warbler (Dendroica kirtlandii), we then illustrated relationships between forest vertical structure, disturbance type and counts of forage species important to the Kirtland's Warbler. The ALI imagery and the Landsat time series were both critical to the result for forest height, which the strong relationship of forest height with disturbance type and age facilitated. Also unique to this study was that seven of the eight image time steps were cloud-gap-filled images: mosaics of the clear parts of several cloudy scenes, in which cloud gaps in a reference scene for each time step are filled with image data from alternate scenes. We created each cloud-cleared image, including a virtually seamless ALI image mosaic, with regression tree normalization of the image data that filled cloud gaps. We also illustrated how viewing time series imagery as red-green-blue composites of tasseled cap wetness (RGB wetness composites) aids reference data collection for classifying tropical forest disturbance type and age.

  9. Rate-dependent interface capture beyond the coffee-ring effect

    NASA Astrophysics Data System (ADS)

    Li, Yanan; Yang, Qiang; Li, Mingzhu; Song, Yanlin

    2016-04-01

    The mechanism of droplet drying is a widely concerned fundamental issue since controlling the deposition morphology of droplet has significant influence on printing, biology pattern, self-assembling and other solution-based devices fabrication. Here we reveal a striking different kinetics-controlled deposition regime beyond the ubiquitous coffee-ring effect that suspended particles tend to kinetically accumulate at the air-liquid interface and deposit uniformly. As the interface shrinkage rate exceeds the particle average diffusion rate, particles in vertical evaporation flow will be captured by the descending surface, producing surface particle jam and forming viscous quasi-solid layer, which dramatically prevents the trapped particles from being transported to drop edge and results in uniform deposition. This simple, robust drying regime will provide a versatile strategy to control the droplet deposition morphology, and a novel direction of interface assembling for fabricating superlattices and high quality photonic crystal patterns.

  10. Rate-dependent interface capture beyond the coffee-ring effect

    PubMed Central

    Li, Yanan; Yang, Qiang; Li, Mingzhu; Song, Yanlin

    2016-01-01

    The mechanism of droplet drying is a widely concerned fundamental issue since controlling the deposition morphology of droplet has significant influence on printing, biology pattern, self-assembling and other solution-based devices fabrication. Here we reveal a striking different kinetics-controlled deposition regime beyond the ubiquitous coffee-ring effect that suspended particles tend to kinetically accumulate at the air-liquid interface and deposit uniformly. As the interface shrinkage rate exceeds the particle average diffusion rate, particles in vertical evaporation flow will be captured by the descending surface, producing surface particle jam and forming viscous quasi-solid layer, which dramatically prevents the trapped particles from being transported to drop edge and results in uniform deposition. This simple, robust drying regime will provide a versatile strategy to control the droplet deposition morphology, and a novel direction of interface assembling for fabricating superlattices and high quality photonic crystal patterns. PMID:27090820

  11. 75 FR 2921 - In the Matter of the Designation of Said Ali al-Shihri, Also Known as Abu-Sayyaf, Also Known as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF STATE In the Matter of the Designation of Said Ali al-Shihri, Also Known as Abu-Sayyaf, Also Known as Abu-Sufyan al-Azidi, Also Known as Abu-Sayyaf al-Shihri, Also Known as Abu Sufian Kadhdhaab Matrook, Also Known as Sa'id Ali Jabir al-Khathim al-Shihri,...

  12. Effects of Rapid Thermal Annealing and Different Oxidants on the Properties of LaxAlyO Nanolaminate Films Deposited by Atomic Layer Deposition.

    PubMed

    Fei, Chenxi; Liu, Hongxia; Wang, Xing; Zhao, Lu; Zhao, Dongdong; Feng, Xingyao

    2017-12-01

    A comparative study of different sequences of two metal precursors [trimethylaluminum (TMA) and Tris(isopropylcyclopentadienyl) lanthanum (La((i)PrCp)3)] for atomic layer deposition (ALD) lanthanum aluminum oxide (LaxAlyO) films is carried out. The percentage compositions of C and N impurity of LaxAlyO films were investigated using in situ X-ray photoelectron spectroscopy (XPS). The effects of different oxidants on the physical and chemical properties and electrical characteristics of LaxAlyO films are studied before and after annealing. Preliminary testing results indicate that the impurity level of LaxAlyO films grown with different oxidants can be well controlled before and after annealing. Analysis indicates the rapid thermal annealing (RTA) and kinds of oxidants have significant effects on the equivalent oxide thickness (EOT), dielectric constant, electrical properties, and stability of LaxAlyO films. Additionally, the change of chemical bond types of rapid thermal annealing effects on the properties of LaxAlyO films are grown with different oxidants also investigated by XPS.

  13. Mineral mapping on the Chilean-Bolivian Altiplano using co-orbital ALI, ASTER and Hyperion imagery: Data dimensionality issues and solutions

    USGS Publications Warehouse

    Hubbard, B.E.; Crowley, J.K.

    2005-01-01

    Hyperspectral data coverage from the EO-1 Hyperion sensor was useful for calibrating Advanced Land Imager (ALI) and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images of a volcanic terrane area of the Chilean-Bolivian Altiplano. Following calibration, the ALI and ASTER datasets were co-registered and joined to produce a 13-channel reflectance cube spanning the Visible to Short Wave Infrared (0.4-2.4 ??m). Eigen analysis and comparison of the Hyperion data with the ALI + ASTER reflectance data, as well as mapping results using various ALI+ASTER data subsets, provided insights into the information dimensionality of all the data. In particular, high spectral resolution, low signal-to-noise Hyperion data were only marginally better for mineral mapping than the merged 13-channel, low spectral resolution, high signal-to-noise ALI + ASTER dataset. Neither the Hyperion nor the combined ALI + ASTER datasets had sufficient information dimensionality for mapping the diverse range of surface materials exposed on the Altiplano. However, it is possible to optimize the use of the multispectral data for mineral-mapping purposes by careful data subsetting, and by employing other appropriate image-processing strategies.

  14. Characterizing magnetospheric electrons from ALIS observations of discrete auroral arcs and quasi-stationary modeling of auroral acceleration

    NASA Astrophysics Data System (ADS)

    Lamy, H.; Simon, C.; Echim, M.; de Keyser, J. M.; Gustavsson, B.; Sergienko, T.; Sandahl, I.; Brandstrom, U.

    2010-12-01

    From a series of images obtained simultaneously with the CCD cameras of the ALIS (Auroral Large Imaging System) network located in Scandinavia, three-dimensional (3D) large-scale structures of discrete auroral arcs can be retrieved in several filters with tomography-like techniques. In particular, the 3D reconstructed volume emission rates at 4278 Å can be used to derive the energy spectra of precipitating magnetospheric electrons in 2D, along and across the arc, with a spatial resolution of approximately 3 km. These spectra directly provide E0, the characteristic energy and ɛm, the total flux energy of precipitating electrons. The latter can be used together with a kinetic modelling of adiabatic motion of particles (Lundin & Sandahl, 1978) and assuming a Maxwellian distribution for magnetospheric electrons, to derive ΔΦ, the field-aligned potential difference between the ionosphere and magnetosphere. The next step is to use a quasi-static magnetosphere-ionosphere coupling model based on the current continuity in the ionosphere (Echim et al, 2007) and the model of tangential discontinuity generators (Roth et al 1993) to determine densities (ne) and temperatures (Te) of the magnetospheric electrons. The model is run iteratively for typical values of magnetospheric ne and Te that are adjusted until ΔΦ provided by the model is in agreement with the one determined from ALIS observations. This technique allows to obtain information about the properties of the generator of the auroral arc, from ground-based observations and quasi-stationary modeling. Future conjugated observations between ALIS and a spacecraft crossing the same magnetic field lines above the acceleration region could be used to validate this novel technique.

  15. AliBiMotif: integrating alignment and biclustering to unravel transcription factor binding sites in DNA sequences.

    PubMed

    Gonçalves, Joana P; Moreau, Yves; Madeira, Sara C

    2012-01-01

    Transcription Factors (TFs) control transcription by binding to specific sites in the promoter regions of the target genes, which can be modelled by structured motifs. In this paper we propose AliBiMotif, a method combining sequence alignment and a biclustering approach based on efficient string matching techniques using suffix trees to unravel approximately conserved sets of blocks (structured motifs) while straightforwardly disregarding non-conserved stretches in-between. The ability to ignore the width of non-conserved regions is a major advantage of the proposed method over other motif finders, as the lengths of the binding sites are usually easier to estimate than the separating distances.

  16. Interface resistance

    NASA Astrophysics Data System (ADS)

    Sinkkonen, Juha

    1983-11-01

    Interface resistance is studied by using the Landauer formula which relates the resistance to the quantum mechanical transmission coefficient. A simple rederivation of the Landauer formula is given. Using a step-like potential barrier as a model for the metal-semiconductor contact an analytical expression for the effective Richardson constant is derived. As an other application the grain boundary resistance in polycrystalline semiconductors is studied. The short-range potential fluctuation associated with the grain boundary is described by a rectangular potential barrier. The results for the grain boundary limited mobility cover both the strong and weak scattering regimes.

  17. Zonation of flood production potential in Kabutar Ali Chai watershed using SCS model

    NASA Astrophysics Data System (ADS)

    Jananeh, Keristineh

    2015-04-01

    Kabutar Ali Chai watershed is located on the southern hillsides of Mishow mountains, 75 km northwest of Tabriz, NW Iran. This watershed is confined to 1390 and 3230 m elevation levels, where the general dip is from north to south. The watershed area is 67.46 km2 and the length of the main stream is about 24.5 km. This is one of the flood basins in the region and considering the availability of precipitation data for the 20 year interval and the possibility of flood occurrence threatening the downstream villages, the flood production investigations in order to prioritize the sub-basins regarding their flood-potential were carried out using the SCS method. In this regard, the watershed area was divided into 4 sections based on physiographic and topographic characteristics and the existing stream network: A1 (the southern and the low-height end of the watershed), A2 (the mid-western half), A3 (the mid-eastern half) and A4 (the northern and highest part). The precipitation data for 20 year interval were gathered from the nearby weather stations of Tabriz, Sahand, Marand and Sharafkhaneh based on which, the average annual precipitation is about 294 mm, with the highest amounts of 415 to 450 mm in A4 sub-basin and the lowest value of 253 mm in the southern A1 sub-basin. According to the time of concentration estimates based on the stream lengths and the elevation differences, this parameter is highest in A1 sub-basin with the rate of 1.64 h and lowest at A3 sub-basin with the rate of 0.35 h. This parameter has negative correlation with the flood production potential. The runoff height is estimated using the SCS method. In order to determine the CN curve Number, the maps of hydrologic groups of soil, land use and vegetation were prepared and combined with each other and then, by taking into account the area of each homogeneous unit, the CN number was calculated for the watershed and the related CN map was prepared. The peak discharge of the hydrologic units across the

  18. Equations of state of anhydrous AlF3 and AlI3: Modeling of extreme condition halide chemistry

    NASA Astrophysics Data System (ADS)

    Stavrou, Elissaios; Zaug, Joseph M.; Bastea, Sorin; Crowhurst, Jonathan C.; Goncharov, Alexander F.; Radousky, Harry B.; Armstrong, Michael R.; Roberts, Sarah K.; Plaue, Jonathan W.

    2015-06-01

    Pressure dependent angle-dispersive x-ray powder diffraction measurements of alpha-phase aluminum trifluoride (α-AlF3) and separately, aluminum triiodide (AlI3) were conducted using a diamond-anvil cell. Results at 295 K extend to 50 GPa. The equations of state of AlF3 and AlI3 were determined through refinements of collected x-ray diffraction patterns. The respective bulk moduli and corresponding pressure derivatives are reported for multiple orders of the Birch-Murnaghan (B-M), finite-strain (F-f), and higher pressure finite-strain (G-g) EOS analysis models. Aluminum trifluoride exhibits an apparent isostructural phase transition at approximately 12 GPa. Aluminum triiodide also undergoes a second-order atomic rearrangement: applied stress transformed a monoclinically distorted face centered cubic (fcc) structure into a standard fcc structural arrangement of iodine atoms. Results from semi-empirical thermochemical computations of energetic materials formulated with fluorine containing reactants were obtained with the aim of predicting the yield of halogenated products.

  19. Synthesis of Multispectral Bands from Hyperspectral Data: Validation Based on Images Acquired by AVIRIS, Hyperion, ALI, and ETM+

    NASA Technical Reports Server (NTRS)

    Blonski, Slawomir; Glasser, Gerald; Russell, Jeffrey; Ryan, Robert; Terrie, Greg; Zanoni, Vicki

    2003-01-01

    Spectral band synthesis is a key step in the process of creating a simulated multispectral image from hyperspectral data. In this step, narrow hyperspectral bands are combined into broader multispectral bands. Such an approach has been used quite often, but to the best of our knowledge accuracy of the band synthesis simulations has not been evaluated thus far. Therefore, the main goal of this paper is to provide validation of the spectral band synthesis algorithm used in the ART software. The next section contains a description of the algorithm and an example of its application. Using spectral responses of AVIRIS, Hyperion, ALI, and ETM+, the following section shows how the synthesized spectral bands compare with actual bands, and it presents an evaluation of the simulation accuracy based on results of MODTRAN modeling. In the final sections of the paper, simulated images are compared with data acquired by actual satellite sensors. First, a Landsat 7 ETM+ image is simulated using an AVIRIS hyperspectral data cube. Then, two datasets collected with the Hyperion instrument from the EO-1 satellite are used to simulate multispectral images from the ALI and ETM+ sensors.

  20. Caractérisation de jonctions ultra-minces réalisées par dopage laser

    NASA Astrophysics Data System (ADS)

    Kerrien, G.; Sarnet, T.; Débarre, D.; Hernandez, M.; Zahorski, D.; Venturini, J.; Laviron, C.; Semeria, M. N.; Boulmer, J.

    2003-06-01

    Cette étude concerne les techniques de recuit laser (LTP) et de dopage laser direct (GILD) de jonctions ultra-minces, nécessaires à la fabrication des composants microélectroniques du futur (générations CMOS sub 0,1 μm). Des jonctions de 20 à 80 nm sont réalisées à l'aide d'un laser à excimères. Le procédé est suivi en temps réel grâce à l'analyse de la réflectivité transitoire à 675 nm. L'évolution de l'activation des dopants est ensuite caractérisée par spectroscopie IR (FTIR). Les résultats obtenus permettent de caractériser les jonctions en termes d'épaisseur dopées, concentration et résistivité. Une comparaison avec des caractérisations classiques (mesures électriques de résistivité, profils SIMS) permet de valider ces mesures et de mettre en évidence l'intérêt des techniques optiques pour la caractérisation in-situ et ex-situ des couches minces dopées réalisées par laser.

  1. [Pathology of adaptation according to Sami-Ali and index of conformity to the Rorschach test in ulcerative rectocolitis].

    PubMed

    Porcelli, P; Zaka, S; Tarantino, S; Sisto, G

    1992-01-01

    According to Sami-Ali's theoretical model the psychosomatic personality is characterised by an adaptation pathology whose main elements are the repression of imaginative thought and conformity to socio-cultural standards. This study examines adaptation pathology using the Rorschach test. The Authors have formulated a conformity index by relating kinestheses (M) and banal perceptions (BAN). The study was carried out on a sample of 41 patients suffering from ulcerous rectocolitis comprising 24 males and 17 women with a mean age of 32 years. As expected in the hypothesis 97.6% of the sample showed M values below the norm, and 68.3% had Ban values higher than normal, whereas the conformity index was positive and tendentially positive in 65.9% of cases. These findings confirm Sami-Ali's theory. Subjects with ulcerous rectocolitis form part of the adaptation pathology which characterised the psychosomatic personality, with an inverse proportionality between imaginative activity (kinesthesia below normal) and conformism (banal perceptions above the norm).

  2. Equations of state of anhydrous AlF3 and AlI3: Modeling of extreme condition halide chemistry.

    PubMed

    Stavrou, Elissaios; Zaug, Joseph M; Bastea, Sorin; Crowhurst, Jonathan C; Goncharov, Alexander F; Radousky, Harry B; Armstrong, Michael R; Roberts, Sarah K; Plaue, Jonathan W

    2015-06-07

    Pressure dependent angle-dispersive x-ray powder diffraction measurements of alpha-phase aluminum trifluoride (α-AlF3) and separately, aluminum triiodide (AlI3) were conducted using a diamond-anvil cell. Results at 295 K extend to 50 GPa. The equations of state of AlF3 and AlI3 were determined through refinements of collected x-ray diffraction patterns. The respective bulk moduli and corresponding pressure derivatives are reported for multiple orders of the Birch-Murnaghan (B-M), finite-strain (F-f), and higher pressure finite-strain (G-g) EOS analysis models. Aluminum trifluoride exhibits an apparent isostructural phase transition at approximately 12 GPa. Aluminum triiodide also undergoes a second-order atomic rearrangement: applied stress transformed a monoclinically distorted face centered cubic (fcc) structure into a standard fcc structural arrangement of iodine atoms. Results from semi-empirical thermochemical computations of energetic materials formulated with fluorine containing reactants were obtained with the aim of predicting the yield of halogenated products.

  3. Interface standardization

    NASA Technical Reports Server (NTRS)

    Spencer, R.; Wong, V.

    1983-01-01

    Central-station applications create a large and attractive market for photovoltaics in the near future. However, some significant barriers lie between the industry of today and realization of that market. Manufacturing capacity and price are two principal impediments. The Utilities, which are the future system owners, are gaining experience with central-station PV power through the Sacramento Municipal Utility District, Hesperia and similar small central-station installations. SMUD has recognized that competition must be maintained to help reduce prices. So little standardization exists that the cost is driven upward to redefine mechanical and electrical interfaces for each vendor. New structues are required for each vendor and nonoptimum field geometries result from attempts to include more than one vendor in an array field. Standards at some hardware level are required.

  4. Endocytosis of the Aspartic Acid/Glutamic Acid Transporter Dip5 Is Triggered by Substrate-Dependent Recruitment of the Rsp5 Ubiquitin Ligase via the Arrestin-Like Protein Aly2 ▿

    PubMed Central

    Hatakeyama, Riko; Kamiya, Masao; Takahara, Terunao; Maeda, Tatsuya

    2010-01-01

    Endocytosis of nutrient transporters is stimulated under various conditions, such as elevated nutrient availability. In Saccharomyces cerevisiae, endocytosis is triggered by ubiquitination of transporters catalyzed by the E3 ubiquitin ligase Rsp5. However, how the ubiquitination is accelerated under certain conditions remains obscure. Here we demonstrate that closely related proteins Aly2/Art3 and Aly1/Art6, which are poorly characterized members of the arrestin-like protein family, mediate endocytosis of the aspartic acid/glutamic acid transporter Dip5. In aly2Δ cells, Dip5 is stabilized at the plasma membrane and is not endocytosed efficiently. Efficient ubiquitination of Dip5 is dependent on Aly2. aly1Δ cells also show deficiency in Dip5 endocytosis, although less remarkably than aly2Δ cells. Aly2 physically interacts in vivo with Rsp5 at its PY motif and also with Dip5, thus serving as an adaptor linking Rsp5 with Dip5 to achieve Dip5 ubiquitination. Importantly, the interaction between Aly2 and Dip5 is accelerated in response to elevated aspartic acid availability. This result indicates that the regulation of Dip5 endocytosis is accomplished by dynamic recruitment of Rsp5 via Aly2. PMID:20956561

  5. New insights into the structure of Om Ali-Thelepte basin, central Tunisia, inferred from gravity data: Hydrogeological implications

    NASA Astrophysics Data System (ADS)

    Harchi, Mongi; Gabtni, Hakim; El Mejri, Hatem; Dassi, Lassaad; Mammou, Abdallah Ben

    2016-08-01

    This work presents new results from gravity data analyses and interpretation within the Om Ali-Thelepte (OAT) basin, central Tunisia. It focuses on the hydrogeological implication, using several qualitative and quantitative techniques such as horizontal gradient, upward continuation and Euler deconvolution on boreholes log data, seismic reflection data and electrical conductivity measurements. The structures highlighted using the filtering techniques suggest that the Miocene aquifer of OAT basin is cut by four major fault systems that trend E-W, NE-SW, NW-SE and NNE-SSW. In addition, a NW-SE gravity model established shows the geometry of the Miocene sandstone reservoir and the Upper Cretaceous limestone rocks. Moreover, the superimposition of the electrical conductivity and the structural maps indicates that the low conductivity values of sampled water from boreholes are located around main faults.

  6. Probing the structures of gold-aluminum alloy clusters AuxAly(-): a joint experimental and theoretical study.

    PubMed

    Khetrapal, Navneet Singh; Jian, Tian; Pal, Rhitankar; Lopez, Gary V; Pande, Seema; Wang, Lai-Sheng; Zeng, Xiao Cheng

    2016-05-05

    Besides the size and structure, compositions can also dramatically affect the properties of alloy nanoclusters. Due to the added degrees of freedom, determination of the global minimum structures for multi-component nanoclusters poses even greater challenges, both experimentally and theoretically. Here we report a systematic and joint experimental/theoretical study of a series of gold-aluminum alloy clusters, AuxAly(-) (x + y = 7,8), with various compositions (x = 1-3; y = 4-7). Well-resolved photoelectron spectra have been obtained for these clusters at different photon energies. Basin-hopping global searches, coupled with density functional theory calculations, are used to identify low-lying structures of the bimetallic clusters. By comparing computed electronic densities of states of the low-lying isomers with the experimental photoelectron spectra, the global minima are determined. It is found that for y ≥ 6 there is a strong tendency to form the magic-number square bi-pyramid motif of Al6(-) in the AuxAly(-) clusters, suggesting that the Al-Al interaction dominates the Au-Au interaction in the mixed clusters. A closely related trend is that for x > 1, the gold atoms tend to be separated by Al atoms unless only the magic-number Al6(-) square bi-pyramid motif is present, suggesting that in the small-sized mixed clusters, Al and Au components do not completely mix with one another. Overall, the Al component appears to play a more dominant role due to the high robustness of the magic-number Al6(-) square bi-pyramid motif, whereas the Au component tends to be either "adsorbed" onto the Al6(-) square bi-pyramid motif if y ≥ 6, or stays away from one another if x < y < 6.

  7. Solvation Dynamics of CO₂(g) by Monoethanolamine at the Gas-Liquid Interface: A Molecular Mechanics Approach.

    PubMed

    Huang, I-Shou; Li, Jia-Jen; Tsai, Ming-Kang

    2016-12-23

    A classical force field approach was used to characterize the solvation dynamics of high-density CO₂(g) by monoethanolamine (MEA) at the air-liquid interface. Intra- and intermolecular CO₂ and MEA potentials were parameterized according to the energetics calculated at the MP2 and BLYP-D2 levels of theory. The thermodynamic properties of CO₂ and MEA, such as heat capacity and melting point, were consistently predicted using this classical potential. An approximate interfacial simulation for CO₂(g)/MEA(l) was performed to monitor the depletion of the CO₂(g) phase, which was influenced by amino and hydroxyl groups of MEA. There are more intramolecular hydrogen bond interactions notably identified in the interfacial simulation than the case of bulk MEA(l) simulation. The hydroxyl group of MEA was found to more actively approach CO₂ and overpower the amino group to interact with CO₂ at the air-liquid interface. With artificially reducing the dipole moment of the hydroxyl group, CO₂-amino group interaction was enhanced and suppressed CO₂(g) depletion. The hydroxyl group of MEA was concluded to play dual but contradictory roles for CO₂ capture.

  8. Standardised water-soluble extract of Eurycoma longifolia, Tongkat ali, as testosterone booster for managing men with late-onset hypogonadism?

    PubMed

    Tambi, M I B M; Imran, M K; Henkel, R R

    2012-05-01

    In most countries, millions of people are relying on herbal medicines as remedy for numerous ailments. In South-East Asia, Eurycoma longifolia Jack, also known as 'Malaysian ginseng' or Tongkat ali, is used to combat stress and disease and to improve physical strength. Moreover, the compounds of the roots of this plant are reported to have aphrodisiac and testosterone enhancing effects in the rat. Considering that human studies are not available, 76 of 320 patients suffering from late-onset hypogonadism (LOH) were given 200 mg of a standardised water-soluble extract of Tongkat ali for 1 month. The Ageing Males' Symptoms (AMS) according to the standardised rating scale and the serum testosterone concentration were taken. Results show that treatment of LOH patients with this Tongkat ali extract significantly (P < 0.0001) improved the AMS score as well as the serum testosterone concentration. While before treatment only 10.5% of the patients did not show any complaint according to the AMS scale and 35.5% had normal testosterone levels, after the completed treatment 71.7% and 90.8% of the patients showed normal values, respectively. Thus, Tongkat ali extract appears to be useful as a supplement in overcoming the symptoms of LOH and for the management of hypogonadism.

  9. SIRT1 protects rat lung tissue against severe burn-induced remote ALI by attenuating the apoptosis of PMVECs via p38 MAPK signaling

    PubMed Central

    Bai, Xiaozhi; Fan, Lei; He, Ting; Jia, Wenbin; Yang, Longlong; Zhang, Jun; Liu, Yang; Shi, Jihong; Su, Linlin; Hu, Dahai

    2015-01-01

    Silent information regulator type-1 (SIRT1) has been reported to be involved in the cardiopulmonary protection. However, its role in the pathogenesis of burn-induced remote acute lung injury (ALI) is currently unknown. The present study aims to investigate the role of SIRT1 in burn-induced remote ALI and the involved signaling pathway. We observed that SIRT1 expression in rat lung tissue after burn injury appeared an increasing trend after a short period of suppression. The upregulation of SIRT1 stimulated by resveratrol exhibited remission of histopathologic changes, reduction of cell apoptosis, and downregulation of pro-inflammatory cytokines in rat pulmonary tissues suffering from severe burn. We next used primary pulmonary microvascular endothelial cells (PMVECs) challenged by burn serum (BS) to simulate in vivo rat lung tissue after burn injury, and found that BS significantly suppressed SIRT1 expression, increased cell apoptosis, and activated p38 MAPK signaling. The use of resveratrol reversed these effects, while knockdown of SIRT1 by shRNA further augmented BS-induced increase of cell apoptosis and activation of p38 MAPK. Taken together, these results indicate that SIRT1 might protect lung tissue against burn-induced remote ALI by attenuating PMVEC apoptosis via p38 MAPK signaling, suggesting its potential therapeutic effects on the treatment of ALI. PMID:25992481

  10. Comparative Analysis of EO-1 ALI and Hyperion, and Landsat ETM+ Data for Mapping Forest Crown Closure and Leaf Area Index

    PubMed Central

    Pu, Ruiliang; Gong, Peng; Yu, Qian

    2008-01-01

    In this study, a comparative analysis of capabilities of three sensors for mapping forest crown closure (CC) and leaf area index (LAI) was conducted. The three sensors are Hyperspectral Imager (Hyperion) and Advanced Land Imager (ALI) onboard EO-1 satellite and Landsat-7 Enhanced Thematic Mapper Plus (ETM+). A total of 38 mixed coniferous forest CC and 38 LAI measurements were collected at Blodgett Forest Research Station, University of California at Berkeley, USA. The analysis method consists of (1) extracting spectral vegetation indices (VIs), spectral texture information and maximum noise fractions (MNFs), (2) establishing multivariate prediction models, (3) predicting and mapping pixel-based CC and LAI values, and (4) validating the mapped CC and LAI results with field validated photo-interpreted CC and LAI values. The experimental results indicate that the Hyperion data are the most effective for mapping forest CC and LAI (CC mapped accuracy (MA) = 76.0%, LAI MA = 74.7%), followed by ALI data (CC MA = 74.5%, LAI MA = 70.7%), with ETM+ data results being least effective (CC MA = 71.1%, LAI MA = 63.4%). This analysis demonstrates that the Hyperion sensor outperforms the other two sensors: ALI and ETM+. This is because of its high spectral resolution with rich subtle spectral information, of its short-wave infrared data for constructing optimal VIs that are slightly affected by the atmosphere, and of its more available MNFs than the other two sensors to be selected for establishing prediction models. Compared to ETM+ data, ALI data are better for mapping forest CC and LAI due to ALI data with more bands and higher signal-to-noise ratios than those of ETM+ data. PMID:27879906

  11. Cross-calibration of MODIS with ETM+ and ALI sensors for long-term monitoring of land surface processes

    USGS Publications Warehouse

    Meyer, D.; Chander, G.

    2006-01-01

    Increasingly, data from multiple sensors are used to gain a more complete understanding of land surface processes at a variety of scales. Although higher-level products (e.g., vegetation cover, albedo, surface temperature) derived from different sensors can be validated independently, the degree to which these sensors and their products can be compared to one another is vastly improved if their relative spectroradiometric responses are known. Most often, sensors are directly calibrated to diffuse solar irradiation or vicariously to ground targets. However, space-based targets are not traceable to metrological standards, and vicarious calibrations are expensive and provide a poor sampling of a sensor's full dynamic range. Crosscalibration of two sensors can augment these methods if certain conditions can be met: (1) the spectral responses are similar, (2) the observations are reasonably concurrent (similar atmospheric & solar illumination conditions), (3) errors due to misregistrations of inhomogeneous surfaces can be minimized (including scale differences), and (4) the viewing geometry is similar (or, some reasonable knowledge of surface bi-directional reflectance distribution functions is available). This study explores the impacts of cross-calibrating sensors when such conditions are met to some degree but not perfectly. In order to constrain the range of conditions at some level, the analysis is limited to sensors where cross-calibration studies have been conducted (Enhanced Thematic Mapper Plus (ETM+) on Landsat-7 (L7), Advance Land Imager (ALI) and Hyperion on Earth Observer-1 (EO-1)) and including systems having somewhat dissimilar geometry, spatial resolution & spectral response characteristics but are still part of the so-called "A.M. constellation" (Moderate Resolution Imaging Spectrometer (MODIS) aboard the Terra platform). Measures for spectral response differences and methods for cross calibrating such sensors are provided in this study. These

  12. Optimization of an air–liquid interface exposure system for assessing toxicity of airborne nanoparticles

    PubMed Central

    Latvala, Siiri; Hedberg, Jonas; Möller, Lennart; Odnevall Wallinder, Inger; Karlsson, Hanna L.

    2016-01-01

    Abstract The use of refined toxicological methods is currently needed for characterizing the risks of airborne nanoparticles (NPs) to human health. To mimic pulmonary exposure, we have developed an air–liquid interface (ALI) exposure system for direct deposition of airborne NPs on to lung cell cultures. Compared to traditional submerged systems, this allows more realistic exposure conditions for characterizing toxicological effects induced by airborne NPs. The purpose of this study was to investigate how the deposition of silver NPs (AgNPs) is affected by different conditions of the ALI system. Additionally, the viability and metabolic activity of A549 cells was studied following AgNP exposure. Particle deposition increased markedly with increasing aerosol flow rate and electrostatic field strength. The highest amount of deposited particles (2.2 μg cm–2) at cell‐free conditions following 2 h exposure was observed for the highest flow rate (390 ml min–1) and the strongest electrostatic field (±2 kV). This was estimated corresponding to deposition efficiency of 94%. Cell viability was not affected after 2 h exposure to clean air in the ALI system. Cells exposed to AgNPs (0.45 and 0.74 μg cm–2) showed significantly (P < 0.05) reduced metabolic activities (64 and 46%, respectively). Our study shows that the ALI exposure system can be used for generating conditions that were more realistic for in vitro exposures, which enables improved mechanistic and toxicological studies of NPs in contact with human lung cells.Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd. PMID:26935862

  13. Media independent interface. Interface control document

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A Media Independent Interface (MII) is specified, using current standards in the industry. The MII is described in hierarchical fashion. At the base are IEEE/International Standards Organization (ISO) documents (standards) which describe the functionality of the software modules or layers and their interconnection. These documents describe primitives which are to transcent the MII. The intent of the MII is to provide a universal interface to one or more Media Access Contols (MACs) for the Logical Link Controller and Station Manager. This interface includes both a standardized electrical and mechanical interface and a standardized functional specification which defines the services expected from the MAC.

  14. Synthesis of Multispectral Bands from Hyperspectral Data: Validation Based on Images Acquired by AVIRIS, Hyperion, ALI, and ETM+

    NASA Technical Reports Server (NTRS)

    Blonksi, Slawomir; Gasser, Gerald; Russell, Jeffrey; Ryan, Robert; Terrie, Greg; Zanoni, Vicki

    2001-01-01

    Multispectral data requirements for Earth science applications are not always studied rigorously studied before a new remote sensing system is designed. A study of the spatial resolution, spectral bandpasses, and radiometric sensitivity requirements of real-world applications would focus the design onto providing maximum benefits to the end-user community. To support systematic studies of multispectral data requirements, the Applications Research Toolbox (ART) has been developed at NASA's Stennis Space Center. The ART software allows users to create and assess simulated datasets while varying a wide range of system parameters. The simulations are based on data acquired by existing multispectral and hyperspectral instruments. The produced datasets can be further evaluated for specific end-user applications. Spectral synthesis of multispectral images from hyperspectral data is a key part of the ART software. In this process, hyperspectral image cubes are transformed into multispectral imagery without changes in spatial sampling and resolution. The transformation algorithm takes into account spectral responses of both the synthesized, broad, multispectral bands and the utilized, narrow, hyperspectral bands. To validate the spectral synthesis algorithm, simulated multispectral images are compared with images collected near-coincidentally by the Landsat 7 ETM+ and the EO-1 ALI instruments. Hyperspectral images acquired with the airborne AVIRIS instrument and with the Hyperion instrument onboard the EO-1 satellite were used as input data to the presented simulations.

  15. Noise disturbance caused by outdoor activities--a simulated-environment study for Ali Sami Yen Stadium, İstanbul.

    PubMed

    Dal, Zeynep; Akdağ, Neşe Yüğrük

    2011-03-01

    Negative effects of noise on individuals, the inevitable result of urbanization, have become a significant urban problem in our day. Introduction of an approach to the noise problem on an urban-planning scale lightens the burden of measures required to be taken against noise at the stages of regional and developmental planning. Stadiums, which should be also evaluated from the point of noise problem when planning decisions are made on the urban planning scale, may cause very serious problems differing depending on the region they are located in. In this article, various dimensions of the noise problem caused by stadiums have been exemplified by making an assessment on Ali Sami Yen football stadium located in Mecidiyeköy district which is among important residential and commercial centres of İstanbul or Turkey. When the simulation results obtained for ordinary days and match days are evaluated, it has been found out that the people living in the area are exposed to noise levels substantially exceeding the acceptable values. Results of the survey conducted in the area have clearly revealed the existence of noise problem, too.

  16. Tongkat Ali as a potential herbal supplement for physically active male and female seniors--a pilot study.

    PubMed

    Henkel, Ralf R; Wang, Ruxiang; Bassett, Susan H; Chen, Tao; Liu, Na; Zhu, Ying; Tambi, Mohd Ismail

    2014-04-01

    Tongkat Ali (Eurycoma longifolia; TA) is known to increase testosterone levels and alleviate aging males' symptoms. This study aimed at investigating TA as an ergogenic supplement for elderly people. Thirteen physically active male and 12 physically active female seniors (57-72 years) were supplemented with 400-mg TA extract daily for 5 weeks. Standard hematological parameters were taken. In addition, the concentrations of total and free testosterone, dihydroepiandrosterone, cortisol, insulin-like growth factor-1, and sex hormone-binding globulin were analyzed. As additional biochemical parameters, blood urea nitrogen and creatine kinase as parameters of kidney function and muscle damage, respectively, as well as the muscle strength by a simple handgrip test were determined. After treatment, hemoglobin, testosterone, and dihydroepiandrosterone concentrations, and the ratio of total testosterone/cortisol and muscle force remained significantly lower in female seniors than in male seniors. Hematocrit and erythrocyte count in male seniors increased slightly but were significantly higher than in female seniors. Treatment resulted in significant increases in total and free testosterone concentrations and muscular force in men and women. The increase in free testosterone in women is thought to be due to the significant decline in sex hormone-binding globulin concentrations. The study affirms the ergogenic benefit of TA through enhanced muscle strength.

  17. Evaluation of Acute 13-Week Subchronic Toxicity and Genotoxicity of the Powdered Root of Tongkat Ali (Eurycoma longifolia Jack).

    PubMed

    Li, Ching-Hao; Liao, Jiunn-Wang; Liao, Po-Lin; Huang, Wei-Kuang; Tse, Ling-Shan; Lin, Cheng-Hui; Kang, Jaw-Jou; Cheng, Yu-Wen

    2013-01-01

    Tongkat Ali (Eurycoma longifolia) is an indigenous traditional herb in Southern Asia. Its powdered root has been processed to produce health supplements, but no detailed toxicology report is available. In this study, neither mutagenicity nor clastogenicity was noted, and acute oral LD50 was more than 6 g/kg b.w. After 4-week subacute and 13-week subchronic exposure paradigms (0, 0.6, 1.2, and 2 g/kg b.w./day), adverse effects attributable to test compound were not observed with respect to body weight, hematology, serum biochemistry, urinalysis, macropathology, or histopathology. However, the treatment significantly reduced prothrombin time, partial thromboplastin time, blood urea nitrogen, creatinine, aspartate aminotransferase, creatine phosphate kinase, lactate dehydrogenase, and cholesterol levels, especially in males (P < 0.05). These changes were judged as pharmacological effects, and they are beneficial to health. The calculated acceptable daily intake (ADI) was up to 1.2 g/adult/day. This information will be useful for product development and safety management.

  18. Effects of Eurycoma longifolia Jack (Tongkat Ali) on the initiation of sexual performance of inexperienced castrated male rats.

    PubMed

    Ang, H H; Cheang, H S; Yusof, A P

    2000-01-01

    We studied the effects of Eurycoma longifolia Jack, commonly known as Tongkat Ali in Malaysia, on the initiation of sexual performance and the weights of sexual accessories in inexperienced castrated male rats. The doses of 200, 400 and 800 mg/kg body weight, which were extracted from E. longifolia Jack, were orally administered to the rats twice daily for 10 days prior to the tests and continued throughout the test period. Testosterone was used as a positive control after injecting 15 mg/kg daily subcutaneously for 32 days. Results showed that E. longifolia Jack produced a dose-dependent increase in sexual performance of the treated animals, but the E. longifolia Jack groups showed lower sexual performance in mounting, intromission and ejaculation than the testosterone group. Further results also showed that E. longifolia Jack promoted the growth of both ventral prostate and seminal vesicles as compared with the control, but the growth of sexual accessories at 800 mg/kg of butanol, methanol, water and chloroform fractions of E. longifolia Jack was less than that of testosterone treated group. The present study therefore gives further evidence of the folkuse of E. longifolia as an aphrodisiac.

  19. Alis, A State-of-the-Art Optical Observation Network for the Exploration of Polar Atmospheric Processes

    NASA Astrophysics Data System (ADS)

    Aso, T.; Steen, Å.; Brändström, U.; Gustavsson, B.; Urashima, A.; Ejiri, M.

    An optical group at the Swedish Institute of Space Physics in Kiruna, Sweden has been developing the ALIS (Auroral Large Imaging System) multi-station optical observing network which makes it possible to obtain composite monochromatic 2-D images over a fairly wide field-of-view (FOV), and more interestingly, a CT (Computed Tomography) image set for the retrieval of 3-D structure of aurora by adjusting vergence angles of cameras to a common volume. National Institute of Polar Research, Japan is collaborating in observation and analysis. At the moment, the network has 6 stations separated from each other by about 50 km.Each station houses a monochromatic CCD (Charge Coupled Device) imaging system mounted on the steerable azimuth/elevation drive along with a house keeping unit and supervising computer linked to the control center via a telephone line. Altitude profiles of luminosity for stable arc and aurora vortex at 557.7nm and recently at 427.8nm are analysed by the algebraic reconstruction technique and compared with sophisticated numerical modelling of auroral emission rate. Conjunctions with satellites and radars are now intensively explored towards comprehensive understanding of the formation and electrodynamics of aurora. Imaging of polar stratospheric clouds is also attempted in relation to arctic environmental studies

  20. Effect of Heme Oxygenase-1 on Mitofusin-1 protein in LPS-induced ALI/ARDS in rats

    PubMed Central

    Yu, Jianbo; Wang, Ying; Li, Zhen; Dong, Shuan; Wang, Dan; Gong, Lirong; Shi, Jia; Zhang, Yuan; Liu, Daquan; Mu, Rui

    2016-01-01

    Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a common and important oxidative stress in the lung. Mitochondrial fusion responds to the normal morphology and function of cells and is finely regulated by mitochondrial fusion proteins, such as mitofusin-1 protein (Mfn1), mitofusin-2 protein (Mfn2) and optical atrophy 1 (OPA1). Additionally, Mfn1 has been identified as the most important protein in mitochondrial fusion. Heme oxygenase-1 (HO-1) is a stress-inducible protein that plays a critical role in protecting against oxidative stress. However, whether the protection of HO-1 is related to mitochondrial fusion is still a question. Thus, our in vitro and in vivo experiments aimed to identify the relationship between HO-1 and Mfn1. Here, we used Hemin and ZnPP-IX as treatments in an in vivo experiment. Then, HO-1 and Mfn1 were measured using RT-PCR and Western blotting. Supernatants were analyzed for MDA, SOD, and ROS. Our results implied that HO-1 upregulation suppressed oxidative stress induced by LPS, and the possible mechanism could be associated with Mfn1 and the PI3K/Akt pathway. PMID:27830717

  1. Evaluation of Acute 13-Week Subchronic Toxicity and Genotoxicity of the Powdered Root of Tongkat Ali (Eurycoma longifolia Jack)

    PubMed Central

    Liao, Jiunn-Wang; Liao, Po-Lin; Huang, Wei-Kuang; Tse, Ling-Shan; Lin, Cheng-Hui; Kang, Jaw-Jou; Cheng, Yu-Wen

    2013-01-01

    Tongkat Ali (Eurycoma longifolia) is an indigenous traditional herb in Southern Asia. Its powdered root has been processed to produce health supplements, but no detailed toxicology report is available. In this study, neither mutagenicity nor clastogenicity was noted, and acute oral LD50 was more than 6 g/kg b.w. After 4-week subacute and 13-week subchronic exposure paradigms (0, 0.6, 1.2, and 2 g/kg b.w./day), adverse effects attributable to test compound were not observed with respect to body weight, hematology, serum biochemistry, urinalysis, macropathology, or histopathology. However, the treatment significantly reduced prothrombin time, partial thromboplastin time, blood urea nitrogen, creatinine, aspartate aminotransferase, creatine phosphate kinase, lactate dehydrogenase, and cholesterol levels, especially in males (P < 0.05). These changes were judged as pharmacological effects, and they are beneficial to health. The calculated acceptable daily intake (ADI) was up to 1.2 g/adult/day. This information will be useful for product development and safety management. PMID:24062779

  2. Revisiting a many-body model for water based on a single polarizable site: from gas phase clusters to liquid and air/liquid water systems.

    PubMed

    Réal, Florent; Vallet, Valérie; Flament, Jean-Pierre; Masella, Michel

    2013-09-21

    We present a revised version of the water many-body model TCPE [M. Masella and J.-P. Flament, J. Chem. Phys. 107, 9105 (1997)], which is based on a static three charge sites and a single polarizable site to model the molecular electrostatic properties of water, and on an anisotropic short range many-body energy term specially designed to accurately model hydrogen bonding in water. The parameters of the revised model, denoted TCPE/2013, are here developed to reproduce the ab initio energetic and geometrical properties of small water clusters (up to hexamers) and the repulsive water interactions occurring in cation first hydration shells. The model parameters have also been refined to reproduce two liquid water properties at ambient conditions, the density and the vaporization enthalpy. Thanks to its computational efficiency, the new model range of applicability was validated by performing simulations of liquid water over a wide range of temperatures and pressures, as well as by investigating water liquid/vapor interfaces over a large range of temperatures. It is shown to reproduce several important water properties at an accurate enough level of precision, such as the existence liquid water density maxima up to a pressure of 1000 atm, the water boiling temperature, the properties of the water critical point (temperature, pressure, and density), and the existence of a "singularity" temperature at about 225 K in the supercooled regime. This model appears thus to be particularly well-suited for characterizing ion hydration properties under different temperature and pressure conditions, as well as in different phases and interfaces.

  3. Revisiting a many-body model for water based on a single polarizable site: From gas phase clusters to liquid and air/liquid water systems

    NASA Astrophysics Data System (ADS)

    Réal, Florent; Vallet, Valérie; Flament, Jean-Pierre; Masella, Michel

    2013-09-01

    We present a revised version of the water many-body model TCPE [M. Masella and J.-P. Flament, J. Chem. Phys. 107, 9105 (1997)], which is based on a static three charge sites and a single polarizable site to model the molecular electrostatic properties of water, and on an anisotropic short range many-body energy term specially designed to accurately model hydrogen bonding in water. The parameters of the revised model, denoted TCPE/2013, are here developed to reproduce the ab initio energetic and geometrical properties of small water clusters (up to hexamers) and the repulsive water interactions occurring in cation first hydration shells. The model parameters have also been refined to reproduce two liquid water properties at ambient conditions, the density and the vaporization enthalpy. Thanks to its computational efficiency, the new model range of applicability was validated by performing simulations of liquid water over a wide range of temperatures and pressures, as well as by investigating water liquid/vapor interfaces over a large range of temperatures. It is shown to reproduce several important water properties at an accurate enough level of precision, such as the existence liquid water density maxima up to a pressure of 1000 atm, the water boiling temperature, the properties of the water critical point (temperature, pressure, and density), and the existence of a "singularity" temperature at about 225 K in the supercooled regime. This model appears thus to be particularly well-suited for characterizing ion hydration properties under different temperature and pressure conditions, as well as in different phases and interfaces.

  4. Intracellular Targeting Signals and Lipid Specificity Determinants of the ALA/ALIS P4-ATPase Complex Reside in the Catalytic ALA α-Subunit

    PubMed Central

    Poulsen, Lisbeth R.; Hanisch, Susanne; Meffert, Katharina; Buch-Pedersen, Morten J.; Jakobsen, Mia K.; Pomorski, Thomas Günther; Palmgren, Michael G.

    2010-01-01

    Members of the P4 subfamily of P-type ATPases are believed to catalyze flipping of phospholipids across cellular membranes, in this way contributing to vesicle biogenesis in the secretory and endocytic pathways. P4-ATPases form heteromeric complexes with Cdc50-like proteins, and it has been suggested that these act as β-subunits in the P4-ATPase transport machinery. In this work, we investigated the role of Cdc50-like β-subunits of P4-ATPases for targeting and function of P4-ATPase catalytic α-subunits. We show that the Arabidopsis P4-ATPases ALA2 and ALA3 gain functionality when coexpressed with any of three different ALIS Cdc50-like β-subunits. However, the final cellular destination of P4-ATPases as well as their lipid substrate specificity are independent of the nature of the ALIS β-subunit they were allowed to interact with. PMID:20053675

  5. Investigation on the neutral and anionic BxAlyH2 (x + y = 7, 8, 9) clusters using density functional theory combined with photoelectron spectroscopy.

    PubMed

    Ding, Li-Ping; Shao, Peng; Lu, Cheng; Zhang, Fang-Hui; Ding, Lei; Yuan, Tao Li

    2016-08-17

    The structure and bonding nature of neutral and negatively charged BxAlyH2 (x + y = 7, 8, 9) clusters are investigated with the aid of previously published experimental photoelectron spectra combined with the present density functional theory calculations. The comparison between the experimental photoelectron spectra and theoretical simulated spectra helps to identify the ground state structures. The accuracy of the obtained ground state structures is further verified by calculating their adiabatic electron affinities and vertical detachment energies and comparing them against available experimental data. The results show that the structures of BxAlyH2 transform from three-dimensional to planar structures as the number of boron atoms increases. Moreover, boron atoms tend to bind together forming Bn units. The hydrogen atoms prefer to bind with boron atoms rather than aluminum atoms. The analyses of the molecular orbital on the ground state structures further support the abovementioned results.

  6. In situ imaging of multiphase bio-interfaces at the micro-/nanoscale.

    PubMed

    Chen, Peipei; Jiang, Lei; Han, Dong

    2011-10-17

    The multiphase bio-interfacial system constituted by biological surfaces and their surrounding environment is usually considered to be an essential clue for exploring the mysterious relationship between surface architecture and function. As a visualizing method to understand these systems, in situ imaging of multiphase interfaces (e.g., air/liquid/solid and oil/water/solid systems) at the micro-/nanoscale, still remains a huge challenge, as a result of their heterogeneity and complexity. Here, recent progress on real-space micro-/nanoscale imaging of multiphase bio-interfacial systems is reviewed; this includes several techniques and imaging results on bio-interfaces, such as the lotus leaf, fish scale, living cell's surface, and fresh tissue surface. The results evidently show that interfacial structures have a significant impact on the state of the microscopic multiphase interface, further influencing specific functions. Based on this research, technical innovations, some more complicated multiphase interface systems, and structure-function coupling mechanism are proposed.

  7. Implementation of the final geometry of the V0A detector for the ALICE experiment in the simulator program AliRoot

    SciTech Connect

    Valencia, L.

    2008-07-02

    The V0A trigger detector of the ALICE experiment is a scintillator hodoscope of 32 channels that has been designed and constructed by the Mexican groups at the Instituto de Fisica de la UNAM and the CINVESTAV.In this work, the final geometry of the constructed detector and its support frame have been implemented using the geometrical modeler of the Root framework in order to be able to simulate the response and trigger performance of the detector with AliRoot.

  8. Comparative alteration mineral mapping using visible to shortwave infrared (0.4-2.4 μm) Hyperion, ALI, and ASTER imagery

    USGS Publications Warehouse

    Hubbard, B.E.; Crowley, J.K.; Zimbelman, D.R.

    2003-01-01

    Advanced Land Imager (ALI), Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), and Hyperion imaging spectrometer data covering an area in the Central Andes between Volcan Socompa and Salar de Llullaillaco were used to map hydrothermally altered rocks associated with several young volcanic systems. Six ALI channels in the visible and near-infrared wavelength range (0.4-1.0 ??m) were useful for discriminating between ferric-iron alteration minerals based on the spectral shapes of electronic absorption features seen in continuum-removed spectra. Six ASTER channels in the short wavelength infrared (1.0-2.5 ??m) enabled distinctions between clay and sulfate mineral types based on the positions of band minima related to Al-OH vibrational absorption features. Hyperion imagery embedded in the broader image coverage of ALI and ASTER provided essential leverage for calibrating and improving the mapping accuracy of the multispectral data. This capability is especially valuable in remote areas of the earth where available geologic and other ground truth information is limited.

  9. First-principles study of zinc-blende BxAlyIn1-x-yN quaternary alloy: Alchemical mixing approximation approach

    NASA Astrophysics Data System (ADS)

    Bamgbose, M. K.; Adebambo, P. O.; Badmus, B. S.; Dare, E. O.; Akinlami, J. O.; Adebayo, G. A.

    2016-08-01

    Detailed first-principle calculations of properties in zinc blende quaternary alloy BxAlyIn1-x-yN at various concentrations are investigated using density functional theory (DFT) within virtual crystal approximation (VCA) implemented in alchemical mixing approximation. The calculated bandgaps show direct transitions at Γ-Γ and indirect transitions at Γ-X, which are opened by increasing boron concentration. The density of state (DOS) revealed upper valence band (VB1) domination by p-states atoms, while s-states dominate the lower valence band (VB2); also, the DOS shows the contribution of d-states to the conduction band. The first critical point in the dielectric constant ranges between 0.07-4.47 eV and is due to the first threshold optical transitions in the energy bandgap. Calculated static dielectric function (DF) 𝜖1(0) is between 5.15 and 10.35, an indication that small energy bandgaps yield large static DFs. The present results indicate ZB-BxAlyIn1-x-yN alloys are suitable candidates of deep ultraviolet light emitting diodes (LEDs), laser diodes (LDs) and modern solar cell since the concentrations x and y make the bandgap and lattice constant of ZB-BxAlyIn1-x-yN quaternary alloys tunable to desirable values.

  10. Media independent interface

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The work done on the Media Independent Interface (MII) Interface Control Document (ICD) program is described and recommendations based on it were made. Explanations and rationale for the content of the ICD itself are presented.

  11. Discharge Against Medical Advice in the Pediatric Wards in Boo-ali Sina Hospital, Sari, Iran 2010

    PubMed Central

    Mohseni Saravi, Benyamin; Reza Zadeh, Esmaeil; Siamian, Hasan; Yahghoobian, Mahboobeh

    2013-01-01

    Introduction: Since children neither comprehended nor contribute to the decision, discharge against medical advice is a challenge of health care systems in the world. Therefore, the current study was designed to determine the rate and causes of discharge against medical advice. Methods: This descriptive cross-sectional study was done by reviewing the medical records by census method. Data was analyzed using SPSS software and x2 statistics was used to determine the relationship between variables. The value of P<0.05 was considered significant. Results: Rate of discharged against medical advice was 108 (2.2%). Mean of age and length of stay were 2.8±4 (SD).3 years old and 3.7±5.4 (SD) days, respectively. Totally, 95 patients (88.7%) had health insurance and 65 (60.2%) patients lived in urban areas. History of psychiatric disease and addiction in 22 (20.6%) of the parents were negative. In addition, 100 (92.3%) patients admitted for medical treatment and the others for surgery. The relationship of the signatory with patients (72.3%) was father. Of 108 patients discharged against medical advice, 20 (12%) were readmitted. The relationship between the day of discharge and discharge against medical advice was significant (ρ =0/03). Conclusion: Rate of discharge against medical advice in Boo-ali hospital is the same as the other studies in the same range. The form which is used for this purpose did not have suitable data elements about description of consequence of such discharge, and it has not shown the real causes of discharge against medical advice. PMID:24554800

  12. Quantization of interface currents

    SciTech Connect

    Kotani, Motoko; Schulz-Baldes, Hermann; Villegas-Blas, Carlos

    2014-12-15

    At the interface of two two-dimensional quantum systems, there may exist interface currents similar to edge currents in quantum Hall systems. It is proved that these interface currents are macroscopically quantized by an integer that is given by the difference of the Chern numbers of the two systems. It is also argued that at the interface between two time-reversal invariant systems with half-integer spin, one of which is trivial and the other non-trivial, there are dissipationless spin-polarized interface currents.

  13. Resistance of β-casein at the air-water interface to enzymatic cleavage.

    PubMed

    Lin, Jhih-Min; Ang, Joo Chuan; White, J W

    2010-12-21

    X-ray reflectivity from an air-buffer interfacial β-casein monomolecular film placed on a solution of chymosin (renin) showed unexpectedly slow proteolytic cleavage. To understand this, the separate structures of β-casein and chymosin, the presentation of each molecule to the other at the air/liquid interface, and that of their mixtures is reported. At the air/solution interface, the hydrophobicity of the protein molecules causes orientation and some deformation of the conformation. When β-casein was presented to a chymosin monomolecular interfacial film, the chymosin was largely displaced from the surface, which was accounted for by the different surfactancy of the two molecules at 25 °C. There was no observable proteolysis. In the reverse experiment, a significant enzymatic degradation and the signature of hydrophobic fragments was observed but only at and above an enzyme concentration of 0.015 mg/mL in the substrate. For comparison, the air/solution interface of premixed β-casein with chymosin in phosphate buffer showed that the film was composed of β-casein proteolytic fragments and chymosin.

  14. In vitro assessment of the soft tissue/implant interface using porcine gingival explants.

    PubMed

    Abdulmajeed, Aous A; Willberg, Jaana; Syrjänen, Stina; Vallittu, Pekka K; Närhi, Timo O

    2015-01-01

    The biologic seal of peri-implant soft tissue is crucial for long-term prognosis of oral implants. This in vitro study describes a novel tissue culture model using porcine gingival explants to evaluate the soft tissue/implant interface. Two different types of substrates were investigated: (a) plain polymer: BisGMA-TEGDMA (50-50 %) and (b) unidirectional fiber-reinforced composite (FRC). Porcine gingival explants were obtained from a local slaughterhouse. The experimental implants (n = 4) were inserted into the middle of freshly excised porcine gingival explants and cultured at the air/liquid interface up to 14 days. Porcine gingival explants with no implants served as baseline controls. The specimens were fixed and processed for the preparation of undecalcified samples. Histological analysis of the soft tissue/implant interface was carried out using a light-microscope. Microscopic evaluation suggests that the gingival explants established epithelial and connective tissue attachment to both implant types over the incubation period. FRC surfaces seemed to have a favorable tissue response with a sign of an outward epithelial migration. However, tissue degeneration was observed at the end of the experiment. In conclusion, this in vitro model maintains mucosal viability and ability to histologically evaluate soft tissue attachment to biomaterials rendering it a time efficient and cost effective model that may reduce the need for animal experiments.

  15. Microconical interface fitting and interface grasping tool

    NASA Technical Reports Server (NTRS)

    Gernhardt, Michael L. (Inventor); Wightman, William D. (Inventor); Johnston, Alistair P. (Inventor)

    1994-01-01

    A small and light weight microconical interface fitting may be attached to the surface of a space vehicle or equipment to provide an attachment device for an astronaut or robot to capture the space vehicle or equipment. The microconical interface fitting of the present invention has an axisymmetrical conical body having a base portion with a torque reaction surface for preventing rotation of the interface grasping tool; a cavitated, sunken or hollowed out intermediate locking portion which has a cavity shaped for receiving the latches of the grasping tool and an upper guiding portion for guiding the grasping tool into axial alignment with the microconical interface fitting. The capture is accomplished with an interface grasping tool. The grasping tool comprises an outer sleeve with a handle attached, an inner sleeve which may be raised and lowered within the outer sleeve with a plurality of latches supported at the lower end and a cam to raise and lower the inner sleeve. When the inner sleeve is at its lowest position, the latches form the largest diameter opening for surrounding the microconical fitting and the latches form the smallest diameter or a locking, grasping position when raised to the highest position within the outer sleeve. The inner sleeve may be at an intermediate, capture position which permits the latches to be biased outwardly when contacting the microconical fitting under very low forces to grasp the fitting and permits capture (soft docking) without exact alignment of the fitting and the tool.

  16. User interface support

    NASA Technical Reports Server (NTRS)

    Lewis, Clayton; Wilde, Nick

    1989-01-01

    Space construction will require heavy investment in the development of a wide variety of user interfaces for the computer-based tools that will be involved at every stage of construction operations. Using today's technology, user interface development is very expensive for two reasons: (1) specialized and scarce programming skills are required to implement the necessary graphical representations and complex control regimes for high-quality interfaces; (2) iteration on prototypes is required to meet user and task requirements, since these are difficult to anticipate with current (and foreseeable) design knowledge. We are attacking this problem by building a user interface development tool based on extensions to the spreadsheet model of computation. The tool provides high-level support for graphical user interfaces and permits dynamic modification of interfaces, without requiring conventional programming concepts and skills.

  17. Multimodal neuroelectric interface development

    NASA Technical Reports Server (NTRS)

    Trejo, Leonard J.; Wheeler, Kevin R.; Jorgensen, Charles C.; Rosipal, Roman; Clanton, Sam T.; Matthews, Bryan; Hibbs, Andrew D.; Matthews, Robert; Krupka, Michael

    2003-01-01

    We are developing electromyographic and electroencephalographic methods, which draw control signals for human-computer interfaces from the human nervous system. We have made progress in four areas: 1) real-time pattern recognition algorithms for decoding sequences of forearm muscle activity associated with control gestures; 2) signal-processing strategies for computer interfaces using electroencephalogram (EEG) signals; 3) a flexible computation framework for neuroelectric interface research; and d) noncontact sensors, which measure electromyogram or EEG signals without resistive contact to the body.

  18. 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.

  19. Persistent interface fluid syndrome.

    PubMed

    Hoffman, Richard S; Fine, I Howard; Packer, Mark

    2008-08-01

    We present an unusual case of persistent interface fluid that would not resolve despite normal intraocular pressure and corneal endothelial replacement with Descemet-stripping endothelial keratoplasty. Dissection, elevation, and repositioning of the laser in situ keratomileusis flap were required to resolve the interface fluid. Circumferential corneal graft-host margin scar formation acting as a mechanical strut may have been the cause of the intractable interface fluid.

  20. Effects of JAM-A deficiency or blocking antibodies on neutrophil migration and lung injury in a murine model of ALI.

    PubMed

    Lakshmi, Sowmya P; Reddy, Aravind T; Naik, Meghna U; Naik, Ulhas P; Reddy, Raju C

    2012-11-01

    Transmigration of neutrophils (PMNs) from the vasculature into inflamed tissues, mediated by interactions between PMNs and adhesion molecules on endothelial cells, is an essential aspect of inflammation. The crucial adhesion molecules include junctional adhesion molecule (JAM)-A. Investigation of the role of this molecule in models of inflammatory disease has been limited, however, and results in different disease models have varied. No previous study has addressed JAM-A in lung disease or effects on oxidant stress and proinflammatory cytokines. We use JAM-A knockout mice and blocking antibodies to investigate the role of JAM-A in a murine model of acute lung injury (ALI). With either experimental system, we find that absence of JAM-A activity significantly reduces migration of PMNs into the alveolar space, with a resulting decrease in oxidative stress. However, there is no reduction in whole lung activity of PMN-associated myeloperoxidase, presumably reflecting the histologically observed retention of PMNs in lung tissue. Activity of these retained PMNs may account for our failure to find significant change in markers of lung oxidative stress or cytokine and chemokine levels in plasma, lung, and bronchoalveolar lavage fluid. We likewise see no JAM-A-related changes in markers of capillary permeability or lung injury. A similar lack of congruence between effects on PMN migration and tissue injury has been reported in other disease models and for other adhesion molecules in models of ALI. Our results thus confirm the crucial role of JAM-A in PMN transmigration but demonstrate that transmigration is not essential for other aspects of inflammation or for lung injury in ALI.

  1. Designing the Instructional Interface.

    ERIC Educational Resources Information Center

    Lohr, L. L.

    2000-01-01

    Designing the instructional interface is a challenging endeavor requiring knowledge and skills in instructional and visual design, psychology, human-factors, ergonomic research, computer science, and editorial design. This paper describes the instructional interface, the challenges of its development, and an instructional systems approach to its…

  2. Metaphors for Interface Design.

    ERIC Educational Resources Information Center

    Hutchins, Edwin

    This discussion of the utilization by computer designers and users of metaphors as organizing structures for dealing with the complexity of behavior of human/computer interfaces begins by identifying three types of metaphor that describe various aspects of human-computer interface design, i.e., activity, mode of interaction, and task domain. The…

  3. Thread Pool Interface (TPI)

    SciTech Connect

    Edwards, H. Carter

    2008-04-01

    Thread Pool Interface (TpI) provides a simple interface for running functions written in C or C++ in a thread-parallel mode. Application or library codes may need to perform operations thread-parallel on machines with multicore processors. the TPI library provides a simple mechanism for managing thread activation, deactivation, and thread-parallel execution of application-provided subprograms.

  4. Interface colloidal robotic manipulator

    DOEpatents

    Aronson, Igor; Snezhko, Oleksiy

    2015-08-04

    A magnetic colloidal system confined at the interface between two immiscible liquids and energized by an alternating magnetic field dynamically self-assembles into localized asters and arrays of asters. The colloidal system exhibits locomotion and shape change. By controlling a small external magnetic field applied parallel to the interface, structures can capture, transport, and position target particles.

  5. Operator interface for vehicles

    SciTech Connect

    Bissontz, Jay E

    2015-03-10

    A control interface for drivetrain braking provided by a regenerative brake and a non-regenerative brake is implemented using a combination of switches and graphic interface elements. The control interface comprises a control system for allocating drivetrain braking effort between the regenerative brake and the non-regenerative brake, a first operator actuated control for enabling operation of the drivetrain braking, and a second operator actuated control for selecting a target braking effort for drivetrain braking. A graphic display displays to an operator the selected target braking effort and can be used to further display actual braking effort achieved by drivetrain braking.

  6. Definitive Metabolite Identification Coupled with Automated Ligand Identification System (ALIS) Technology: A Novel Approach to Uncover Structure-Activity Relationships and Guide Drug Design in a Factor IXa Inhibitor Program.

    PubMed

    Zhang, Ting; Liu, Yong; Yang, Xianshu; Martin, Gary E; Yao, Huifang; Shang, Jackie; Bugianesi, Randal M; Ellsworth, Kenneth P; Sonatore, Lisa M; Nizner, Peter; Sherer, Edward C; Hill, Susan E; Knemeyer, Ian W; Geissler, Wayne M; Dandliker, Peter J; Helmy, Roy; Wood, Harold B

    2016-03-10

    A potent and selective Factor IXa (FIXa) inhibitor was subjected to a series of liver microsomal incubations, which generated a number of metabolites. Using automated ligand identification system-affinity selection (ALIS-AS) methodology, metabolites in the incubation mixture were prioritized by their binding affinities to the FIXa protein. Microgram quantities of the metabolites of interest were then isolated through microisolation analytical capabilities, and structurally characterized using MicroCryoProbe heteronuclear 2D NMR techniques. The isolated metabolites recovered from the NMR experiments were then submitted directly to an in vitro FIXa enzymatic assay. The order of the metabolites' binding affinity to the Factor IXa protein from the ALIS assay was completely consistent with the enzymatic assay results. This work showcases an innovative and efficient approach to uncover structure-activity relationships (SARs) and guide drug design via microisolation-structural characterization and ALIS capabilities.

  7. Scalable coherent interface

    SciTech Connect

    Alnaes, K.; Kristiansen, E.H. ); Gustavson, D.B. ); James, D.V. )

    1990-01-01

    The Scalable Coherent Interface (IEEE P1596) is establishing an interface standard for very high performance multiprocessors, supporting a cache-coherent-memory model scalable to systems with up to 64K nodes. This Scalable Coherent Interface (SCI) will supply a peak bandwidth per node of 1 GigaByte/second. The SCI standard should facilitate assembly of processor, memory, I/O and bus bridge cards from multiple vendors into massively parallel systems with throughput far above what is possible today. The SCI standard encompasses two levels of interface, a physical level and a logical level. The physical level specifies electrical, mechanical and thermal characteristics of connectors and cards that meet the standard. The logical level describes the address space, data transfer protocols, cache coherence mechanisms, synchronization primitives and error recovery. In this paper we address logical level issues such as packet formats, packet transmission, transaction handshake, flow control, and cache coherence. 11 refs., 10 figs.

  8. Galaxy-like organization of floaters at the air-water interface of Faraday waves

    NASA Astrophysics Data System (ADS)

    Alarcón, Héctor; Périnet, Nicolas; Gutiérrez, Pablo; Gordillo, Leonardo; Mujica, Nicolás

    2016-11-01

    The fluid properties mismatch across an air-liquid interface allows to trap particles at it. These particles are called floaters and appear in nature at different scales: plankton, organic residues, and garbage, all relevant for the oceanic ecosystem. In static systems they tend to attract or repel each other, depending on their wetting properties and buoyancy. When they are subjected to a flow, such as surface waves, they may drift and form structures at the interface. In a recent work using PIV on Faraday waves, we have measured a streaming flow that emerges inside the bulk, leading to a slow circulation of fluid particles across the liquid. The flow is mainly generated by the viscous shearing at the walls of the container. Our new experiments show that this flow has a remarkable effect on the drift of small hydrophilic particles (floaters), which leads to a rare arrangement of the floaters that resemble rotating galaxies. The forcing amplitude determines the galaxy shape, controlling the number and the length of its arms as well as its rotation velocity. Thanks to FONDECYT POSTDOCTORADO N°3160341, N°3140522, N°3140550.

  9. Data Reorganization Interface

    DTIC Science & Technology

    2007-11-02

    Data Reorganization Interface Kenneth Cain Mercury Computer Systems, Inc. Phone: (978)-967-1645 Email Address: kcain@mc.com Abstract...6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Mercury Computer Systems...18 © 2003 Mercury Computer Systems, Inc. Data Reorganization Interface (DRI) Kenneth Cain Jr. Mercury Computer Systems, Inc. High Performance

  10. VIRTUAL FRAME BUFFER INTERFACE

    NASA Technical Reports Server (NTRS)

    Wolfe, T. L.

    1994-01-01

    Large image processing systems use multiple frame buffers with differing architectures and vendor supplied user interfaces. This variety of architectures and interfaces creates software development, maintenance, and portability problems for application programs. The Virtual Frame Buffer Interface program makes all frame buffers appear as a generic frame buffer with a specified set of characteristics, allowing programmers to write code which will run unmodified on all supported hardware. The Virtual Frame Buffer Interface converts generic commands to actual device commands. The virtual frame buffer consists of a definition of capabilities and FORTRAN subroutines that are called by application programs. The virtual frame buffer routines may be treated as subroutines, logical functions, or integer functions by the application program. Routines are included that allocate and manage hardware resources such as frame buffers, monitors, video switches, trackballs, tablets and joysticks; access image memory planes; and perform alphanumeric font or text generation. The subroutines for the various "real" frame buffers are in separate VAX/VMS shared libraries allowing modification, correction or enhancement of the virtual interface without affecting application programs. The Virtual Frame Buffer Interface program was developed in FORTRAN 77 for a DEC VAX 11/780 or a DEC VAX 11/750 under VMS 4.X. It supports ADAGE IK3000, DEANZA IP8500, Low Resolution RAMTEK 9460, and High Resolution RAMTEK 9460 Frame Buffers. It has a central memory requirement of approximately 150K. This program was developed in 1985.

  11. MER SPICE Interface

    NASA Technical Reports Server (NTRS)

    Sayfi, Elias

    2004-01-01

    MER SPICE Interface is a software module for use in conjunction with the Mars Exploration Rover (MER) mission and the SPICE software system of the Navigation and Ancillary Information Facility (NAIF) at NASA's Jet Propulsion Laboratory. (SPICE is used to acquire, record, and disseminate engineering, navigational, and other ancillary data describing circumstances under which data were acquired by spaceborne scientific instruments.) Given a Spacecraft Clock value, MER SPICE Interface extracts MER-specific data from SPICE kernels (essentially, raw data files) and calculates values for Planet Day Number, Local Solar Longitude, Local Solar Elevation, Local Solar Azimuth, and Local Solar Time (UTC). MER SPICE Interface was adapted from a subroutine, denoted m98SpiceIF written by Payam Zamani, that was intended to calculate SPICE values for the Mars Polar Lander. The main difference between MER SPICE Interface and m98SpiceIf is that MER SPICE Interface does not explicitly call CHRONOS, a time-conversion program that is part of a library of utility subprograms within SPICE. Instead, MER SPICE Interface mimics some portions of the CHRONOS code, the advantage being that it executes much faster and can efficiently be called from a pipeline of events in a parallel processing environment.

  12. A protocol for improving mapping and assessing of seagrass abundance along the West Central Coast of Florida using Landsat TM and EO-1 ALI/Hyperion images

    NASA Astrophysics Data System (ADS)

    Pu, Ruiliang; Bell, Susan

    2013-09-01

    Seagrass habitats are characteristic features of shallow waters worldwide and provide a variety of ecosystem functions. Remote sensing techniques can help collect spatial and temporal information about seagrass resources. In this study, we evaluate a protocol that utilizes image optimization algorithms followed by atmospheric and sunglint corrections to the three satellite sensors [Landsat 5 Thematic Mapper (TM), Earth Observing-1 (EO-1) Advanced Land Imager (ALI) and Hyperion (HYP)] and a fuzzy synthetic evaluation technique to map and assess seagrass abundance in Pinellas County, FL, USA. After image preprocessed with image optimization algorithms and atmospheric and sunglint correction approaches, the three sensors' data were used to classify the submerged aquatic vegetation cover (%SAV cover) into 5 classes with a maximum likelihood classifier. Based on three biological metrics [%SAV, leaf area index (LAI), and Biomass] measured from the field, nine multiple regression models were developed for estimating the three biometrics with spectral variables derived from the three sensors' data. Then, five membership maps were created with the three biometrics along with two environmental factors (water depth and distance-to-shoreline). Finally, seagrass abundance maps were produced by using a fuzzy synthetic evaluation technique and five membership maps. The experimental results indicate that the HYP sensor produced the best results of the 5-class classification of %SAV cover (overall accuracy = 87% and Kappa = 0.83 vs. 82% and 0.77 by ALI and 79% and 0.73 by TM) and better multiple regression models for estimating the three biometrics (R2 = 0.66, 0.62 and 0.61 for %SAV, LAI and Biomass vs. 0.62, 0.61 and 0.55 by ALI and 0.58, 0.56 and 0.52 by TM) for creating seagrass abundance maps along with two environmental factors. Combined our results demonstrate that the image optimization algorithms and the fuzzy synthetic evaluation technique were effective in mapping

  13. Geochemistry of rare earth elements in the Baba Ali magnetite skarn deposit, western Iran - a key to determine conditions of mineralisation

    NASA Astrophysics Data System (ADS)

    Zamanian, Hassan; Radmard, Kaikosrov

    2016-03-01

    The Baba Ali skarn deposit, situated 39 km to the northwest of Hamadan (Iran), is the result of a syenitic pluton that intruded and metamorphosed the diorite host rock. Rare earth element (REE) values in the quartz syenite and diorite range between 35.4 and 560 ppm. Although the distribution pattern of REEs is more and less flat and smooth, light REEs (LREEs) in general show higher concentrations than heavy REEs (HREEs) in different lithounits. The skarn zone reveals the highest REE-enriched pattern, while the ore zone shows the maximum depletion pattern. A comparison of the concentration variations of LREEs (La-Nd), middle REEs (MREEs; Sm-Ho) and HREEs (Er-Lu) of the ore zone samples to the other zones elucidates two important points for the distribution of REEs: 1) the distribution patterns of LREEs and MREEs show a distinct depletion in the ore zone while representing a great enrichment in the skarn facies neighbouring the ore body border and decreasing towards the altered diorite host rock; 2) HREEs show the same pattern, but in the exoskarn do not reveal any distinct increase as observed for LREEs and MREEs. The ratio of La/Y in the Baba Ali skarn ranges from 0.37 to 2.89. The ore zone has the highest La/Y ratio. In this regard the skarn zones exhibit two distinctive portions: 1) one that has La/Y >1 beingadjacent to the ore body and; 2) another one with La/Y < 1 neighbouring altered diorite. Accordingly, the Baba Ali profile, from the quartz syenite to the middle part of the exoskarn, demonstrates chiefly alkaline conditions of formation, with a gradual change to acidic towards the altered diorite host rocks. Utilising three parameters, Ce/Ce*, Eu/Eu* and (Pr/Yb)n, in different minerals implies that the hydrothermal fluids responsible for epidote and garnet were mostly of magmatic origin and for magnetite, actinolite and phlogopite these were of magmatic origin with low REE concentration or meteoric water involved.

  14. Wettability alteration by novel betaines at polymer-aqueous solution interfaces

    NASA Astrophysics Data System (ADS)

    Hu, Song-Shuang; Zhang, Lei; Xu, Zhi-Cheng; Gong, Qing-Tao; Jin, Zhi-Qiang; Luo, Lan; Zhang, Lu; Zhao, Sui

    2015-11-01

    The wettability of alkyl carboxylbetaine (18C) and alkyl sulfobetaine (18S) at polytetrafluoroethylene (PTFE) and polymethylmethacrylate (PMMA) surfaces have been investigated and the different physicochemical parameters such as critical micelle concentration (CMC), surface tension, contact angle, surface excess, adhesional tension and work of adhesion have been estimated. The results show that the contact angle of 18C and 18S for both solids keep almost a constant value in a wide range of surfactant concentration, but the sharp decrease of contact angle appears after CMC of individual surfactant solution because of the continued increase in surfactant molecules adsorption at solid-liquid interface above CMC, which is quite different from traditional surfactants reported in the literature. In addition, 18C has significantly lower contact angle values on PTFE at high concentrations. For PTFE and PMMA there is a linear relationship existing between the adhesional and surface tension in a range of certain concentrations for all investigated surfactants. The values of slope suggest that adsorption of 18C and 18S at PTFE/PMMA-liquid interfaces are less than that at air-liquid, and the orientation of the surfactant molecules at PTFE-liquid and PMMA-liquid interfaces should not be the same. Moreover, the decrease of PTFE-liquid interfacial tension has been observed while the PMMA-liquid interfacial tension increases at first and decreases afterwards for 18C and 18S. Especially for PTFE, the decrease of γSL for 18C is larger than that for 18S, which indicates that 18S molecules may be vertical orientation due to steric effect while the hemimicelle has been formed for 18C at the PTFE interface. On the other hand, the addition of surfactant molecules will adsorb onto monolayer at PMMA surface again through hydrophobic interaction with hydrophilic group toward the bulk phase of solution above CMC.

  15. First-principles study of the magnetic and electronic properties of AMnAs (A=Li, Na, K, Rb, Cs)

    NASA Astrophysics Data System (ADS)

    Zhou, Wenqi; Wu, Shuxiang; Li, Shuwei

    2016-12-01

    Recent studies have demonstrated that antiferromagnetic (AFM) semiconductors are promising alternative materials for spintronic applications. In this work, we report a detailed investigation of the magnetic and electronic properties of AMnAs (A=Li, Na, K, Rb, Cs) using density functional theory. It is found that all studied compounds are ordered antiferromagnetically in the MnAs ab plane, however, along the c axis, NaMnAs is ordered ferromagnetically which is different from the AFM coupling of other materials. These results on magnetic structures are in good agreement with observed facts. Furthermore, our calculations predict that all materials have a semiconducting band structure, which indicates the potential of device applications.

  16. Environmental materials and interfaces

    SciTech Connect

    Not Available

    1991-11-01

    A workshop that explored materials and interfaces research needs relevant to national environmental concerns was conducted at Pacific Northwest Laboratory. The purposes of the workshop were to refine the scientific research directions being planned for the Materials and Interface Program in the Molecular Science Research Center (MSRC) and further define the research and user equipment to the included as part of the proposed Environmental and Molecular Science Laboratory (EMSL). Three plenary information sessions served to outline the background, objectives, and status of the MSRC and EMSL initiatives; selected specific areas with environmentally related materials; and the status of capabilities and facilities planned for the EMSL. Attention was directed to four areas where materials and interface science can have a significant impact on prevention and remediation of environmental problems: in situ detection and characterization of hazardous wastes (sensors), minimization of hazardous waste (separation membranes, ion exchange materials, catalysts), waste containment (encapsulation and barrier materials), and fundamental understanding of contaminant transport mechanisms. During all other sessions, the participants were divided into three working groups for detailed discussion and the preparation of a written report. The working groups focused on the areas of interface structure and chemistry, materials and interface stability, and materials synthesis. These recommendations and suggestions for needed research will be useful for other researchers in proposing projects and for suggesting collaborative work with MSRC researchers. 1 fig.

  17. Magnetic multilayer interface anisotropy

    SciTech Connect

    Pechan, M.J.

    1992-01-01

    Ni/Mo and Ni/V multilayer magnetic anisotropy has been investigated as a function of Ni layer thickness, frequency and temperature. Variable frequency ferromagnetic resonance (FMR) measurements show, for the first time, significant frequency dependence associated with the multilayer magnetic anisotropy. The thickness dependence allows one to extract the interface contribution from the total anisotropy. Temperature dependent FMR (9 GHz) and room temperature magnetization indicate that strain between Ni and the non-magnetic layers is contributing significantly to the source of the interface anisotropy and the state of the interfacial magnetization. In order to examine the interface properties of other transition metal multilayer systems, investigations on Fe/Cu are underway and CoCr/Ag is being proposed. ESR measurements have been reported on Gd substituted YBaCuO superconductors and a novel quasi-equilibrium method has been developed to determine quickly and precisely the ransition temperature.

  18. High temperature interface superconductivity

    NASA Astrophysics Data System (ADS)

    Gozar, A.; Bozovic, I.

    2016-02-01

    High-Tc superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-Tc Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both 'passive' hetero-structures as well as surface-induced effects by external gating are discussed. We conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.

  19. High temperature interface superconductivity

    DOE PAGES

    Gozar, A.; Bozovic, I.

    2016-01-20

    High-Tc superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-Tc Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both ‘passive’ hetero-structures as well as surface-induced effects by external gating are discussed. Here, wemore » conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.« less

  20. High temperature interface superconductivity

    SciTech Connect

    Gozar, A.; Bozovic, I.

    2016-01-20

    High-Tc superconductivity at interfaces has a history of more than a couple of decades. In this review we focus our attention on copper-oxide based heterostructures and multi-layers. We first discuss the technique, atomic layer-by-layer molecular beam epitaxy (ALL-MBE) engineering, that enabled High-Tc Interface Superconductivity (HT-IS), and the challenges associated with the realization of high quality interfaces. Then we turn our attention to the experiments which shed light on the structure and properties of interfacial layers, allowing comparison to those of single-phase films and bulk crystals. Both ‘passive’ hetero-structures as well as surface-induced effects by external gating are discussed. Here, we conclude by comparing HT-IS in cuprates and in other classes of materials, especially Fe-based superconductors, and by examining the grand challenges currently laying ahead for the field.

  1. Profile Interface Generator

    SciTech Connect

    2013-11-09

    The Profile Interface Generator (PIG) is a tool for loosely coupling applications and performance tools. It enables applications to write code that looks like standard C and Fortran functions calls, without requiring that applications link to specific implementations of those function calls. Performance tools can register with PIG in order to listen to only the calls that give information they care about. This interface reduces the build and configuration burden on application developers and allows semantic instrumentation to live in production codes without interfering with production runs.

  2. Optical encryption interface

    NASA Technical Reports Server (NTRS)

    Jackson, Deborah J. (Inventor)

    1998-01-01

    An analog optical encryption system based on phase scrambling of two-dimensional optical images and holographic transformation for achieving large encryption keys and high encryption speed. An enciphering interface uses a spatial light modulator for converting a digital data stream into a two dimensional optical image. The optical image is further transformed into a hologram with a random phase distribution. The hologram is converted into digital form for transmission over a shared information channel. A respective deciphering interface at a receiver reverses the encrypting process by using a phase conjugate reconstruction of the phase scrambled hologram.

  3. Virtual interface environment workstations

    NASA Technical Reports Server (NTRS)

    Fisher, S. S.; Wenzel, E. M.; Coler, C.; Mcgreevy, M. W.

    1988-01-01

    A head-mounted, wide-angle, stereoscopic display system controlled by operator position, voice and gesture has been developed at NASA's Ames Research Center for use as a multipurpose interface environment. This Virtual Interface Environment Workstation (VIEW) system provides a multisensory, interactive display environment in which a user can virtually explore a 360-degree synthesized or remotely sensed environment and can viscerally interact with its components. Primary applications of the system are in telerobotics, management of large-scale integrated information systems, and human factors research. System configuration, research scenarios, and research directions are described.

  4. Modal Interfaces in Hawaii

    NASA Technical Reports Server (NTRS)

    Wright, E. Alvey

    1974-01-01

    Hawaii, an archipelago where transportation distances are short but the interfaces are many, seeks elimination of modal changes by totally-submerged hydrofoil craft operating at the water surface directly between tourist resort destinations, by dual mode rapid transit vehicles operating directly between the deplaning bridges at Honolulu International Airport and hotel porte-cochere at Waikiki, by demand responsive vehicles for collection and distribution operating on fixed guideways for line haul, and by roll-on/roll-off inter-island ferries for all models of manually operated ground vehicles. The paper also describes facilitation of unavoidable interfaces by innovative sub-systems.

  5. Interfacing the Digital.

    ERIC Educational Resources Information Center

    Dietz, Steve

    In the last 5 years, there has been at times heated debate not only about how best to present digital and specifically networked art in an institutional context but also whether to do so at all. Not all of the discussion revolves around issues of physical interfaces to such works, but their onsite presentation is a critical concern for both…

  6. Virtual interface environment

    NASA Technical Reports Server (NTRS)

    Fisher, Scott S.

    1988-01-01

    A head-mounted, wide-angle, stereoscopic display system controlled by operator position, voice and gesture is under development for use as a multipurpose interface environment. Initial applications of the system are in telerobotics, data-management and human factors research. System configuration and research directions are described.

  7. A Thermistor Interface.

    ERIC Educational Resources Information Center

    Kamin, Gary D.; Dowden, Edward

    1987-01-01

    Describes the use of a precalibrated stainless steel thermistor, interfaced with an Apple computer, in chemistry experiments. Discusses the advantages of "instant" temperature readings in experiments requiring that readings be taken at certain intervals. Outlines such an experiment which investigates freezing point depressions. (TW)

  8. Interfacing with a DMM.

    ERIC Educational Resources Information Center

    Beatty, Jim

    1985-01-01

    Suggests purchasing a digital multimer (DMM) with an IEEE-488 option to interface an instrument to a microcomputer, indicating that a DMM is well protected from overloads and is easy to connect. An example of its use in an experiment involving hydrolysis of tertiary butyl alcohol (with program listing) is given. (JN)

  9. Photochemistry at Interfaces

    SciTech Connect

    Eisenthal, Kenneth B

    2015-02-24

    We have advanced our capabilities to investigate ultrafast excited state dynamics at a liquid interface using a pump to excite molecules to higher electronic states and then probe the subsequent time evolution of the interfacial molecules with femtosecond time delayed vibrational SFG.

  10. the EXFOR interface

    SciTech Connect

    Brown, D. A.

    2011-03-10

    The x4i package is an interface to the EXFOR nuclear data library. It simplifies retrieval of EXFOR entries and can automatically parse them, allowing one to extract cross-section (and other) data in a simple, plot-able format. x4i also understands and can parse the entire reaction string, allowing one to build a strategy for processing the data

  11. Interface It Yourself.

    ERIC Educational Resources Information Center

    Westling, Bruce D.; Bahe, Margaret E.

    1986-01-01

    Describes several ways to build data collection devices for microcomputers. The interface devices connect with either the computer's game port or an analog-to-digital converter. Discusses how teachers have designed the equipment and appropriate software to use with the computer in biology teaching. (TW)

  12. Novel Alginate Lyase (Aly5) from a Polysaccharide-Degrading Marine Bacterium, Flammeovirga sp. Strain MY04: Effects of Module Truncation on Biochemical Characteristics, Alginate Degradation Patterns, and Oligosaccharide-Yielding Properties

    PubMed Central

    Han, Wenjun; Gu, Jingyan; Cheng, Yuanyuan; Liu, Huihui; Li, Yuezhong

    2015-01-01

    Alginate lyases are important tools for oligosaccharide preparation, medical treatment, and energy bioconversion. Numerous alginate lyases have been elucidated. However, relatively little is known about their substrate degradation patterns and product-yielding properties, which is a limit to wider enzymatic applications and further enzyme improvements. Herein, we report the characterization and module truncation of Aly5, the first alginate lyase obtained from the polysaccharide-degrading bacterium Flammeovirga. Aly5 is a 566-amino-acid protein and belongs to a novel branch of the polysaccharide lyase 7 (PL7) superfamily. The protein rAly5 is an endolytic enzyme of alginate and associated oligosaccharides. It prefers guluronate (G) to mannuronate (M). Its smallest substrate is an unsaturated pentasaccharide, and its minimum product is an unsaturated disaccharide. The final alginate digests contain unsaturated oligosaccharides that generally range from disaccharides to heptasaccharides, with the tetrasaccharide fraction constituting the highest mass concentration. The disaccharide products are identified as ΔG units. While interestingly, the tri- and tetrasaccharide fractions each contain higher proportions of ΔG to ΔM ends, the larger final products contain only ΔM ends, which constitute a novel oligosaccharide-yielding property of guluronate lyases. The deletion of the noncatalytic region of Aly5 does not alter its M/G preference but significantly decreases the enzymatic activity and enzyme stability. Notably, the truncated protein accumulates large final oligosaccharide products but yields fewer small final products than Aly5, which are codetermined by its M/G preference to and size enlargement of degradable oligosaccharides. This study provides novel enzymatic properties and catalytic mechanisms of a guluronate lyase for potential uses and improvements. PMID:26519393

  13. Novel Alginate Lyase (Aly5) from a Polysaccharide-Degrading Marine Bacterium, Flammeovirga sp. Strain MY04: Effects of Module Truncation on Biochemical Characteristics, Alginate Degradation Patterns, and Oligosaccharide-Yielding Properties.

    PubMed

    Han, Wenjun; Gu, Jingyan; Cheng, Yuanyuan; Liu, Huihui; Li, Yuezhong; Li, Fuchuan

    2015-10-30

    Alginate lyases are important tools for oligosaccharide preparation, medical treatment, and energy bioconversion. Numerous alginate lyases have been elucidated. However, relatively little is known about their substrate degradation patterns and product-yielding properties, which is a limit to wider enzymatic applications and further enzyme improvements. Herein, we report the characterization and module truncation of Aly5, the first alginate lyase obtained from the polysaccharide-degrading bacterium Flammeovirga. Aly5 is a 566-amino-acid protein and belongs to a novel branch of the polysaccharide lyase 7 (PL7) superfamily. The protein rAly5 is an endolytic enzyme of alginate and associated oligosaccharides. It prefers guluronate (G) to mannuronate (M). Its smallest substrate is an unsaturated pentasaccharide, and its minimum product is an unsaturated disaccharide. The final alginate digests contain unsaturated oligosaccharides that generally range from disaccharides to heptasaccharides, with the tetrasaccharide fraction constituting the highest mass concentration. The disaccharide products are identified as ΔG units. While interestingly, the tri- and tetrasaccharide fractions each contain higher proportions of ΔG to ΔM ends, the larger final products contain only ΔM ends, which constitute a novel oligosaccharide-yielding property of guluronate lyases. The deletion of the noncatalytic region of Aly5 does not alter its M/G preference but significantly decreases the enzymatic activity and enzyme stability. Notably, the truncated protein accumulates large final oligosaccharide products but yields fewer small final products than Aly5, which are codetermined by its M/G preference to and size enlargement of degradable oligosaccharides. This study provides novel enzymatic properties and catalytic mechanisms of a guluronate lyase for potential uses and improvements.

  14. Foreword: Quasicrystals at Interfaces

    NASA Astrophysics Data System (ADS)

    Fournée, Vincent; Ledieu, Julian; Thiel, Patricia

    2008-08-01

    The term 'quasicrystals' stands for quasiperiodic crystals and by no means signifies that they are imperfect crystals. Quasicrystals represent a well-ordered state of matter just like periodic crystals, characterized by diffraction peaks as sharp as those for nearly perfect crystals such as silicon. But their long range order is aperiodic, and therefore they cannot be described by the periodic repetition of a small unit cell like normal crystals. Instead, quasiperiodic structures can be described as the three-dimensional restriction of a periodic structure embedded in a hyperspace of dimension N > 3. For example, a six-dimensional cubic lattice is used to generate the icosahedral quasilattice in three-dimensions. This is a general property of quasiperiodic functions, an archetype being the function f(x) = cos(x) + cos(√2x), which is the sum of two periodic functions with incommensurate periods. This function can be regarded as the restriction along the line with irrational slope y = √2x of the function F(x, y) = cos(x) + cos(y), which is periodic in the (x, y) plan. Quasicrystalline materials were discovered 25 years ago by D Shechtman et al in rapidly solidified Al-Mn alloys. Many quasicrystals have been identified since then in binary and ternary systems. Most of them present non-crystallographic rotational symmetry like five-fold or ten-fold axes. Interest in this new class of materials was further driven by their potentially useful physical properties, either in the form of functional coatings or as reinforcement particle in composites. These practical aspects in turn raised fundamental questions about the nature of interfaces between periodic and quasiperiodic materials. Interfaces are regions of high energy compared to the bulk, where atomic positions need to be adjusted on both sides of the interface to accommodate the two different lattices. How to describe interfaces and how nature minimizes the interface energy between a periodic and a quasiperiodic

  15. Easy-to-use interface

    SciTech Connect

    Blattner, M M; Blattner, D O; Tong, Y

    1999-04-01

    Easy-to-use interfaces are a class of interfaces that fall between public access interfaces and graphical user interfaces in usability and cognitive difficulty. We describe characteristics of easy-to-use interfaces by the properties of four dimensions: selection, navigation, direct manipulation, and contextual metaphors. Another constraint we introduced was to include as little text as possible, and what text we have will be in at least four languages. Formative evaluations were conducted to identify and isolate these characteristics. Our application is a visual interface for a home automation system intended for a diverse set of users. The design will be expanded to accommodate the visually disabled in the near future.

  16. Interface Configuration Experiment: Preliminary Results

    NASA Technical Reports Server (NTRS)

    Concus, Paul; Finn, Robert; Weislogel, Mark

    1994-01-01

    The Interface Configuration Experiment (ICE) was carried out on USML-1 to investigate liquid-gas interfaces in certain rotationally-symmetric containers having prescribed, mathematically derived shapes. These containers have the property that they admit an entire continuum of distinct equilibrium rotationally-symmetric interfaces for a given liquid volume and contact angle. Furthermore, it can be shown that none of these interfaces can be stable. It was found, after the containers were filled in orbit, that an initial equilibrium interface from the symmetric continuum re-oriented, when perturbed, to a stable interface that was not rotationally symmetric, in accordance with the mathematical theory.

  17. PREFACE: Water at interfaces Water at interfaces

    NASA Astrophysics Data System (ADS)

    Gallo, P.; Rovere, M.

    2010-07-01

    This special issue is devoted to illustrating important aspects and significant results in the field of modeling and simulation of water at interfaces with solutes or with confining substrates, focusing on a range of temperatures from ambient to supercooled. Understanding the behavior of water, in contact with different substrates and/or in solutions, is of pivotal importance for a wide range of applications in physics, chemistry and biochemistry. Simulations of confined and/or interfacial water are also relevant for testing how different its behavior is with respect to bulk water. Simulations and modeling in this field are of particular importance when studying supercooled regions where water shows anomalous properties. These considerations motivated the organization of a workshop at CECAM in the summer of 2009 which aimed to bring together scientists working with computer simulations on the properties of water in various environments with different methodologies. In this special issue, we collected a variety of interesting contributions from some of the speakers of the workshop. We have roughly classified the contributions into four groups. The papers of the first group address the properties of interfacial and confined water upon supercooling in an effort to understand the relation with anomalous behavior of supercooled bulk water. The second group deals with the specific problem of solvation. The next group deals with water in different environments by considering problems of great importance in technological and biological applications. Finally, the last group deals with quantum mechanical calculations related to the role of water in chemical processes. The first group of papers is introduced by the general paper of Stanley et al. The authors discuss recent progress in understanding the anomalies of water in bulk, nanoconfined, and biological environments. They present evidence that liquid water may display 'polymorphism', a property that can be present in

  18. TNF-α mediated increase of HIF-1α inhibits VASP expression, which reduces alveolar-capillary barrier function during acute lung injury (ALI).

    PubMed

    Tang, Mengjie; Tian, Yihao; Li, Doulin; Lv, Jiawei; Li, Qun; Kuang, Changchun; Hu, Pengchao; Wang, Ying; Wang, Jing; Su, Ke; Wei, Lei

    2014-01-01

    Acute lung injury (ALI) is an inflammatory disorder associated with reduced alveolar-capillary barrier function and increased pulmonary vascular permeability. Vasodilator-stimulated phosphoprotein (VASP) is widely associated with all types of modulations of cytoskeleton rearrangement-dependent cellular morphology and function, such as adhesion, shrinkage, and permeability. The present studies were conducted to investigate the effects and mechanisms by which tumor necrosis factor-alpha (TNF-α) increases the tight junction permeability in lung tissue associated with acute lung inflammation. After incubating A549 cells for 24 hours with different concentrations (0-100 ng/mL) of TNF-α, 0.1 to 8 ng/mL TNF-α exhibited no significant effect on cell viability compared with the 0 ng/mL TNF-α group (control group). However, 10 ng/mL and 100 ng/mL TNF-α dramatically inhibited the viability of A549 cells compared with the control group (*p<0.05). Monolayer cell permeability assay results indicated that A549 cells incubated with 10 ng/mL TNF-α for 24 hours displayed significantly increased cell permeability (*p<0.05). Moreover, the inhibition of VASP expression increased the cell permeability (*p<0.05). Pretreating A549 cells with cobalt chloride (to mimic a hypoxia environment) increased protein expression level of hypoxia inducible factor-1α (HIF-1α) (*p<0.05), whereas protein expression level of VASP decreased significantly (*p<0.05). In LPS-induced ALI mice, the concentrations of TNF-α in lung tissues and serum significantly increased at one hour, and the value reached a peak at four hours. Moreover, the Evans Blue absorption value of the mouse lung tissues reached a peak at four hours. The HIF-1α protein expression level in mouse lung tissues increased significantly at four hours and eight hours (**p<0.001), whereas the VASP protein expression level decreased significantly (**p<0.01). Taken together, our data demonstrate that HIF-1α acts downstream of TNF-α to

  19. Multifunctional microcontrollable interface module

    NASA Astrophysics Data System (ADS)

    Spitzer, Mark B.; Zavracky, Paul M.; Rensing, Noa M.; Crawford, J.; Hockman, Angela H.; Aquilino, P. D.; Girolamo, Henry J.

    2001-08-01

    This paper reports the development of a complete eyeglass- mounted computer interface system including display, camera and audio subsystems. The display system provides an SVGA image with a 20 degree horizontal field of view. The camera system has been optimized for face recognition and provides a 19 degree horizontal field of view. A microphone and built-in pre-amp optimized for voice recognition and a speaker on an articulated arm are included for audio. An important feature of the system is a high degree of adjustability and reconfigurability. The system has been developed for testing by the Military Police, in a complete system comprising the eyeglass-mounted interface, a wearable computer, and an RF link. Details of the design, construction, and performance of the eyeglass-based system are discussed.

  20. Immunochemistry at interfaces.

    PubMed Central

    Nygren, H; Stenberg, M

    1989-01-01

    The immunochemistry of antibody binding to solid-phase immobilized antigen is reviewed. Experimental data are compared with different theoretical models of reaction mechanisms at solid-liquid interfaces. It was found that reactions at the solid-liquid interface can become limited by the diffusion rate due to depletion of reactants close to the surface, even though the intrinsic bimolecular reaction at the surface is reaction-rate limited. The forward reaction-rate constant decreases with increasing concentration of bound antibodies at the surface, and when not limited by diffusion the forward reaction rate can be more than 1000-fold slower than the corresponding reaction in a liquid solution. Possible explanations for this phenomenon are discussed. The dissociation of bound antibodies is a slow process at solid phases. The antigen-antibody complexes formed are practically irreversible. Some evidence is presented which indicates that the stability of these complexes can be due to attractive lateral interactions between bound antibodies. PMID:2649437

  1. Interface scattering in polycrystalline thermoelectrics

    SciTech Connect

    Popescu, Adrian; Haney, Paul M.

    2014-03-28

    We study the effect of electron and phonon interface scattering on the thermoelectric properties of disordered, polycrystalline materials (with grain sizes larger than electron and phonons' mean free path). Interface scattering of electrons is treated with a Landauer approach, while that of phonons is treated with the diffuse mismatch model. The interface scattering is embedded within a diffusive model of bulk transport, and we show that, for randomly arranged interfaces, the overall system is well described by effective medium theory. Using bulk parameters similar to those of PbTe and a square barrier potential for the interface electron scattering, we identify the interface scattering parameters for which the figure of merit ZT is increased. We find the electronic scattering is generally detrimental due to a reduction in electrical conductivity; however, for sufficiently weak electronic interface scattering, ZT is enhanced due to phonon interface scattering.

  2. SNE Industrial Fieldbus Interface

    NASA Technical Reports Server (NTRS)

    Lucena, Angel; Raines, Matthew; Oostdyk, Rebecca; Mata, Carlos

    2011-01-01

    Programmable logic controllers (PLCs) have very limited diagnostic and no prognostic capabilities, while current smart sensor designs do not have the capability to communicate over Fieldbus networks. The aim is to interface smart sensors with PLCs so that health and status information, such as failure mode identification and measurement tolerance, can be communicated via an industrial Fieldbus such as ControlNet. The SNE Industrial Fieldbus Interface (SIFI) is an embedded device that acts as a communication module in a networked smart sensor. The purpose is to enable a smart sensor to communicate health and status information to other devices, such as PLCs, via an industrial Fieldbus networking protocol. The SNE (Smart Network Element) is attached to a commercial off-the-shelf Any bus-S interface module through the SIFI. Numerous Anybus-S modules are available, each one designed to interface with a specific Fieldbus. Development of the SIFI focused on communications using the ControlNet protocol, but any of the Anybus-S modules can be used. The SIFI communicates with the Any-bus module via a data buffer and mailbox system on the Anybus module, and supplies power to the module. The Anybus module transmits and receives data on the Fieldbus using the proper protocol. The SIFI is intended to be connected to other existing SNE modules in order to monitor the health and status of a transducer. The SIFI can also monitor aspects of its own health using an onboard watchdog timer and voltage monitors. The SIFI also has the hardware to drive a touchscreen LCD (liquid crystal display) unit for manual configuration and status monitoring.

  3. Magnetic multilayer interface anisotropy

    SciTech Connect

    Pechan, M.J.

    1990-01-01

    Ni/Mo and Ni/V multilayer magnetic anisotropy has been investigated as a function of Ni layer thickness, frequency and temperature. Variable frequency ferromagnetic resonance (FMR) measurements show, for the first time, significant frequency dependence associated with the multilayer magnetic anisotropy. The thickness dependence allows one to extract the interface contribution from the total anisotropy. Temperature dependent FMR (9 GHz) and room temperature magnetization indicate that strain between Ni and the non-magnetic layers is contributing significantly to the source of the interface anisotropy and the state of the interfacial magnetization. In order to examine the interface properties of other transition metal multilayer systems, investigations on Fe/Cu are underway and CoCr/Ag is being proposed. ESR measurements have been reported on Gd substituted YBaCuO superconductors and a novel quasi-equilibrium method has been developed to determine quickly and precisely the transition temperature. During the next project period the P.I. proposes to (1) extend the variable frequency FMR measurements to low temperature, where extremely large interface anisotropies are known to obtain in Ni/Mo and Ni/V and are proposed to exist in Ni/W; (2) obtain accurate dc anisotropies via a novel, variable temperature torque magnetometer currently under construction; (3) expand upon his initial findings in Fe/Cu multilayer investigations; (4) begin anisotropy investigations on Co/Ag and CoCr/Ag multilayers where the easy magnetization direction depends upon the Cr concentration; (4) make and characterize Bi based superconductors according to resistivity, thermal conductivity and thermoelectric power and construct YBaCuO based superconducting loop-gap'' resonators for use in his magnetic resonance work.

  4. Magnetic multilayer interface anisotropy

    SciTech Connect

    Pechan, M.J.

    1991-01-01

    Ni/Mo and Ni/V multilayer magnetic anisotropy has been investigated as a function of Ni layer thickness, frequency and temperature. Variable frequency ferromagnetic resonance (FMR) measurements show, for the first time, significant frequency dependence associated with the multilayer magnetic anisotropy. The thickness dependence allows one to extract the interface contribution from the total anisotropy. Temperature dependant FMR (9 GHz) and room temperature magnetization indicate that strain between Ni and the non-magnetic layers if contributing significantly to the source of the interface anisotropy and the state of the interfacial magnetization. In order to examine the interface properties of other transition metal multilayer systems, investigations on Fe/Cu are underway and CoCr/Ag is being proposed. ESR measurements have been reported on Gd substituted YBaCuO superconductors and a novel quasi-equilibrium method has been developed to determine quickly and precisely the transition temperature. During the next project the P.I. proposes to (1) extend the variable frequency FMR measurements to low temperature, where extremely large interface anisotropies are known to obtain in Ni/Mo and Ni/V and are proposed to exist in Ni/W; (2) obtain accurate dc anisotropies via a novel, variable temperature torque magnetometer currently under construction; (3) expand upon his initial findings in Fe/Cu multilayer investigations; (4) begin anisotropy investigations on Co/Ag and CoCr/Ag multilayers where the easy magnetization direction depends upon the Cr concentration; (4) make and characterize Bi based superconductors according to resistivity, thermal conductivity and thermoelectric power and construct YBaCuO based superconducting loop-gap'' resonators for use in his magnetic resonance work. 2 figs.

  5. Metaphors for Interface Design

    DTIC Science & Technology

    1987-04-01

    deturms what soa of thing the user thinks the computer is. Is it a conversational parmer? An environment for action? A tool box and materials shed...user takes that action. It means instead that it is simply not possible, using dte tools that the interface language pro- vides, to generate an...manipulated by the people in the course of doing the task. These include the navigation chart, plotting tools , measurement tools , written records

  6. Systems interface biology

    PubMed Central

    Doyle, Francis J; Stelling, Jörg

    2006-01-01

    The field of systems biology has attracted the attention of biologists, engineers, mathematicians, physicists, chemists and others in an endeavour to create systems-level understanding of complex biological networks. In particular, systems engineering methods are finding unique opportunities in characterizing the rich behaviour exhibited by biological systems. In the same manner, these new classes of biological problems are motivating novel developments in theoretical systems approaches. Hence, the interface between systems and biology is of mutual benefit to both disciplines. PMID:16971329

  7. User Interface Software Tools

    DTIC Science & Technology

    1994-08-01

    97. 19. Mark A. Flecchia and R. Daniel Bergeron. Specifying Complex Dialogs in ALGAE. Human Factors in Computing Systems, CHI+GI󈨛, Toronto, Ont...Spreadsheet Model. Tech. Rept. GIT-GVU-93-20, Georgia Tech Graphics, Visualization and Usability Center, May, 1993. 35. Daniel H.H. Ingalls. "I’he Smalltalk...Interactive Graphical Applications". Comm. ACM 36,4 (April 1993), 41-55. User Interface Software Tools -39 38. Anthony Karrer and Walt Scacchi . Requirements

  8. Standard interface file handbook

    SciTech Connect

    Shapiro, A.; Huria, H.C. )

    1992-10-01

    This handbook documents many of the standard interface file formats that have been adopted by the US Department of Energy to facilitate communications between and portability of, various large reactor physics and radiation transport software packages. The emphasis is on those files needed for use of the VENTURE/PC diffusion-depletion code system. File structures, contents and some practical advice on use of the various files are provided.

  9. User Interface Design Patterns

    DTIC Science & Technology

    2010-07-01

    the beginning of our research) led us to Glade (glade.gnome.org), a cross- platform GUI builder platform that saves its descriptive files in XML format...Major consideration was initially given to Java Netbeans and Java Eclipse, and later extended to Glade .) The saved XML files fully describe... Glade -designed user interfaces. Glade libraries are available for numerous programming languages on many computing platforms. This makes the choice of

  10. Virtual button interface

    DOEpatents

    Jones, Jake S.

    1999-01-01

    An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch.

  11. Virtual button interface

    DOEpatents

    Jones, J.S.

    1999-01-12

    An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment are disclosed. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch. 4 figs.

  12. Systems interface biology.

    PubMed

    Doyle, Francis J; Stelling, Jörg

    2006-10-22

    The field of systems biology has attracted the attention of biologists, engineers, mathematicians, physicists, chemists and others in an endeavour to create systems-level understanding of complex biological networks. In particular, systems engineering methods are finding unique opportunities in characterizing the rich behaviour exhibited by biological systems. In the same manner, these new classes of biological problems are motivating novel developments in theoretical systems approaches. Hence, the interface between systems and biology is of mutual benefit to both disciplines.

  13. Optical Neural Interfaces

    PubMed Central

    Warden, Melissa R.; Cardin, Jessica A.; Deisseroth, Karl

    2014-01-01

    Genetically encoded optical actuators and indicators have changed the landscape of neuroscience, enabling targetable control and readout of specific components of intact neural circuits in behaving animals. Here, we review the development of optical neural interfaces, focusing on hardware designed for optical control of neural activity, integrated optical control and electrical readout, and optical readout of population and single-cell neural activity in freely moving mammals. PMID:25014785

  14. The THOSE remote interface

    NASA Astrophysics Data System (ADS)

    Klawon, Kevin; Gold, Josh; Bachman, Kristen

    2013-05-01

    The DIA, in conjunction with the Army Research Lab (ARL), wants to create an Unmanned Ground Sensor (UGS) controller that is (a) interoperable across all controller platforms, (b) capable of easily adding new sensors, radios, and processes and (c) backward compatible with existing UGS systems. To achieve this, a Terra Harvest controller was created that used Java JRE 1.6 and an Open Services Gateway initiative (OSGi) platform, named Terra Harvest Open Software Environment (THOSE). OSGi is an extensible framework that provides a modularized environment for deploying functionality in "bundles". These bundles can publish, discover, and share services available from other external bundles or bundles provided by the controller core. With the addition of a web GUI used for interacting with THOSE, a natural step was then to create a common remote interface that allows 3rd party real-time interaction with the controller. This paper provides an overview of the THOSE system and its components as well as a description of the architectural structure of the remote interface, highlighting the interactions occurring between the controller and the remote interface and its role in providing a positive user experience for managing UGSS functions.

  15. ADAM -- Interface Module Reference Manual

    NASA Astrophysics Data System (ADS)

    Chipperfield, A. J.; Kelly, B. D.; Wright, S. L.

    ADAM Interface Modules provide an interface between ADAM application programs and the rest of the system. This document describes in detail the facilities available with ADAM Interface Modules and the rules for using them. It is intended as a reference manual and should shed light on some of the finer points of the ADAM parameter system. Readers requiring an introduction to Interface Modules should read SG/4.

  16. Eye-voice-controlled interface

    NASA Technical Reports Server (NTRS)

    Glenn, Floyd A., III; Iavecchia, Helene P.; Ross, Lorna V.; Stokes, James M.; Weiland, William J.

    1986-01-01

    The Ocular Attention-Sensing Interface System (OASIS) is an innovative human-computer interface which utilizes eye movement and voice commands to communicate messages between the operator and the system. This report initially describes some technical issues relevant to the development of such an interface. The results of preliminary experiments which evaluate alternative eye processing algorithms and feedback techniques are presented. Candidate interface applications are also discussed.

  17. Graphic Interfaces and Online Information.

    ERIC Educational Resources Information Center

    Percival, J. Mark

    1990-01-01

    Discusses the growing importance of the use of Graphic User Interfaces (GUIs) with microcomputers and online services. Highlights include the development of graphics interfacing with microcomputers; CD-ROM databases; an evaluation of HyperCard as a potential interface to electronic mail and online commercial databases; and future possibilities.…

  18. Special Interfaces for Special Students.

    ERIC Educational Resources Information Center

    Tinker, Robert

    1983-01-01

    Computer software can be made accessible to physically handicapped individuals using interfaces. The trick performed by the interface is to make the handicapped individual's responses mediated through the interface indistinguishable from inputs that the software expects from users in normal hardware configurations. Several of these keyboard…

  19. User interfaces for voice applications.

    PubMed Central

    Kamm, C

    1995-01-01

    This paper discusses some of the aspects of task requirements, user expectations, and technological capabilities that influence the design of a voice interface and then identifies several components of user interfaces that are particularly critical in successful voice applications. Examples from several applications are provided to demonstrate how these components are used to produce effective voice interfaces. PMID:7479721

  20. User interfaces for voice applications.

    PubMed

    Kamm, C

    1995-10-24

    This paper discusses some of the aspects of task requirements, user expectations, and technological capabilities that influence the design of a voice interface and then identifies several components of user interfaces that are particularly critical in successful voice applications. Examples from several applications are provided to demonstrate how these components are used to produce effective voice interfaces.

  1. User Interfaces for Voice Applications

    NASA Astrophysics Data System (ADS)

    Kamm, Candace

    1995-10-01

    This paper discusses some of the aspects of task requirements, user expectations, and technological capabilities that influence the design of a voice interface and then identifies several components of user interfaces that are particularly critical in successful voice applications. Examples from several applications are provided to demonstrate how these components are used to produce effective voice interfaces.

  2. Thesaurus-Enhanced Search Interfaces.

    ERIC Educational Resources Information Center

    Shiri, Ali Asghar; Revie, Crawford; Chowdhury, Gobinda

    2002-01-01

    Discussion of user interfaces to information retrieval systems focuses on interfaces that incorporate thesauri as part of their searching and browsing facilities. Discusses research literature related to information searching behavior, information retrieval interface evaluation, search term selection, and query expansion; and compares thesaurus…

  3. Ionic ASi2N3 (A=Li, Na, K and Rb) stabilized by the covalent Si-N bonding: First-principles calculations

    NASA Astrophysics Data System (ADS)

    Zhang, Huijun; Ren, Jiadong; Wu, Lailei; Zhang, Jingwu

    2017-01-01

    The structural, elastic and electronic properties of LiSi2N3 and its substitutions by Na, K and Rb were investigated through first-principles computations. The expansion of lattice parameters of ASi2N3 from Li, Na, K to Rb is found to be determined by the bond angle of Si-N1-Si, which suggests a possible way to improve the lithium ionic conductivity by substitutions. ASi2N3 (A=Li, Na, K and Rb) shows the similar elastic behaviors, while the electronic band gap gradually decreases from 5.1 to 3.4 eV from LiSi2N3 to RbSi2N3. Interestingly, the analysis of electronic structure, crystal orbital Hamiltonian populations and Bader charges shows that the covalence of Si-N bonding is critical for the stability of ASi2N3 phase. Among ASi2N3 phases, there is a relatively high ionicity in NaSi2N3; the Si-N bond strength in [Si2N3]- net for KSi2N3 and RbSi2N3 is comparable to LiSi2N3, but stronger than NaSi2N3.

  4. Structural phase stability, electronic structure and mechanical properties of alkali metal hydrides AMH4 (A=Li, Na; M=B, AL)

    NASA Astrophysics Data System (ADS)

    Santhosh, M.; Rajeswarapalanichamy, R.

    2016-01-01

    The structural stability of Alkali metal hydrides AMH4 (A=Li, Na; M=B, Al) is analyzed among the various crystal structures, namely hexagonal (P63mc), tetragonal (P42/nmc), tetragonal (P-421c), tetragonal (I41/a), orthorhombic (Pnma) and monoclinic (P21/c). It is observed that, orthorhombic (Pnma) phase is the most stable structure for LiBH4, monoclinic (P21/c) for LiAlH4, tetragonal (P42/nmc) for NaBH4 and tetragonal (I41/a) for NaAlH4 at normal pressure. Pressure induced structural phase transitions are observed in LiBH4, LiAlH4, NaBH4 and NaAlH4 at the pressures of 4 GPa, 36.1 GPa, 26.5 GPa and 46 GPa respectively. The electronic structure reveals that these metal hydrides are wide band gap insulators. The calculated elastic constants indicate that these metal hydrides are mechanically stable at normal pressure.

  5. Raman scattering of magnetic excitations in Y1-x Prx Ba2Cu3-yAlyO7-δ single crystals

    NASA Astrophysics Data System (ADS)

    Rübhausen, M.; Dieckmann, N.; Bock, A.; Merkt, U.; Widder, W.; Braun, H. F.

    1996-11-01

    Magnetic excitations and their role for the superconductivity in cuprate superconductors have been widely discussed in the literature. Here, we present a study of Y1-x Prx Ba2Cu3-yAlyO7-δ single crystals using Raman spectroscopy in an energy range of 50 10000 cm-1 Raman shift. The high energy range is dominated by a two-magnon scattering process at 3J, where J is the superexchange energy. In the Pr-123 single crystal, we find J = 720 cm-1, a damping of the one-magnon states Γ = 200 cm-1, and a resonance energy of 2.79eV for the two-magnon excitation. The two-magnon peak shows a continuous increase of the one-magnon damping with decreasing x and a nearly constant J across the phase transition to the superconductor. Especially, we find a weak two-magnon peak for a superconductor with a Tc = 86 K.

  6. Effect of integrated pest management on controlling zoonotic cutaneous leishmaniasis in Emamzadeh Agha Ali Abbas (AS) District, Isfahan province, 2006-2009

    PubMed Central

    Nilforoushzadeh, Mohammad Ali; Shirani-Bidabadi, Leila; Saberi, Sedigheh; Hosseini, Seyed Mohsen; Jaffary, Fariba

    2014-01-01

    Background: Cutaneous leishmaniasis (CL) is still considered as a health problem in the world. Several methods of control in different regions, together with obtaining integrated information on its natural foci, are needed to decrease its prevalence. This study was designed to evaluate the effects of simultaneous interventions on CL control. Materials and Methods: A standard questionnaire was used to identify patients among pilgrims to Emamzadeh Agha Ali Abbas (Isfahan Province, Iran). Subsequently, three methods of controlling the disease, including, spraying residential buildings with Baygon, baiting with zinc phosphide poisons, changing the vegetative cover of the region, improving the environment, and mounting a mesh on all doors and windows of buildings in residential areas were used. The control measures were then evaluated by comparing the number of pilgrims affected by CL after and before the interventions. Results: While 23 pilgrims (1.4%) were affected with CL before the intervention (pretest), five (0.3%) persons were found to have CL after taking control measures. The Chi-square test did not indicate any significant difference in the relative frequency of CL (P = 0.731). Conclusion: The only scientific method for preventing and controlling zoonotic CL (ZCL) is a combination of the control methods (improving the environment and fighting off the disease districts and vectors) together with changing the vegetative cover of the region. Any measure for controlling this disease must be taken and programmed in accordance with the relevant experts’ views, in coordination with the participation of other organizations and the society. PMID:24818102

  7. Luminescent properties of SrZn2(PO4)2:Tb3+ and its luminescence improvement by incorporating A+ (A=Li, Na, and K)

    NASA Astrophysics Data System (ADS)

    Li, Panlai; Wang, Zhijun; Yang, Zhiping; Guo, Qinglin

    2014-12-01

    A novel green phosphor SrZn2(PO4)2:Tb3+ is synthesized by a high temperature solid-state method, and its luminescent property is investigated. X-ray diffraction patterns of SrZn2(PO4)2:Tb3+ indicate a similarity crystalline phase to SrZn2(PO4)2. SrZn2(PO4)2:Tb3+ shows green emission under 369 nm excitation, and the prominent luminescence in green (544 nm) due to 5D4-7F5 transition of Tb3+. For the 544 nm emission, excitation spectrum has several excitation band from 200 nm to 400 nm. Emission intensity of SrZn2(PO4)2:Tb3+ is influenced by Tb3+ concentration, and concentration quenching effect of Tb3+ in SrZn2(PO4)2 is also observed. With incorporating A+ (A=Li, Na, and K) as compensator charge, the emission intensity of SrZn2(PO4)2:Tb3+ can be obviously enhanced. CIE color coordinates of SrZn2(PO4)2:Tb3+ locate in the green region. The results indicate this phosphor may be a potential application in white LEDs.

  8. InxGa1-xAs/AlyGa1-yAs/AlzGa1-zAs asymmetric step quantum-well middle wavelength infrared detectors

    NASA Astrophysics Data System (ADS)

    Wu, W. G.; Chang, K.; Jiang, D. S.; Li, Y. X.; Zheng, H. Z.; Liu, H. C.

    2001-10-01

    InxGa1-xAs/AlyGa1-yAs/AlzGa1-zAs asymmetric step quantum-well middle wavelength (3-5 μm) infrared detectors are fabricated. The components display photovoltaic-type photocurrent response as well as the bias-controlled modulation of the peak wavelength of the main response, which is ascribed to the Stark shifts of the intersubband transitions from the local ground states to the extended first excited states in the quantum wells, at the 3-5.3 μm infrared atmospheric transmission window. The blackbody detectivity (Dbb*) of the detectors reaches to about 1.0×1010cm Hz1/2/W at 77 K under bias of ±7 V. By expanding the electron wave function in terms of normalized plane wave basis within the framework of the effective-mass envelope-function theory, the linear Stark effects of the intersubband transitions between the ground and first excited states in the asymmetric step well are calculated. The obtained results agree well with the corresponding experimental measurements.

  9. Single-interface Casimir torque

    NASA Astrophysics Data System (ADS)

    Morgado, Tiago A.; Silveirinha, Mário G.

    2016-10-01

    A different type of Casimir-type interaction is theoretically predicted: a single-interface torque at a junction of an anisotropic material and a vacuum or another material system. The torque acts to reorient the polarizable microscopic units of the involved materials near the interface, and thus to change the internal structure of the materials. The single-interface torque depends on the zero-point energy of the interface localized and extended modes. Our theory demonstrates that the single-interface torque is essential to understand the Casimir physics of material systems with anisotropic elements and may influence the orientation of the director of nematic liquid crystals.

  10. Crystal structures of hydrates of simple inorganic salts. III. Water-rich aluminium halide hydrates: AlCl3 · 15H2O, AlBr3 · 15H2O, AlI3 · 15H2O, AlI3 · 17H2O and AlBr3 · 9H2O.

    PubMed

    Schmidt, Horst; Hennings, Erik; Voigt, Wolfgang

    2014-09-01

    Water-rich aluminium halide hydrate structures are not known in the literature. The highest known water content per Al atom is nine for the perchlorate and fluoride. The nonahydrate of aluminium bromide, stable pentadecahydrates of aluminium chloride, bromide and iodide, and a metastable heptadecahydrate of the iodide have now been crystallized from low-temperature solutions. The structures of these hydrates were determined and are discussed in terms of the development of cation hydration spheres. The pentadecahydrate of the chloride and bromide are isostructural. In AlI(3) · 15H2O, half of the Al(3+) cations are surrounded by two complete hydration spheres, with six H2O in the primary and 12 in the secondary. For the heptadecahydrate of aluminium iodide, this hydration was found for every Al(3+).

  11. Conceptual Framework for Aquatic Interfaces

    NASA Astrophysics Data System (ADS)

    Lewandowski, J.; Krause, S.

    2015-12-01

    Aquatic interfaces are generally characterized by steep gradients of physical, chemical and biological properties due to the contrast between the two adjacent environments. Innovative measurement techniques are required to study the spatially heterogeneous and temporally variable processes. Especially the different spatial and temporal scales are a large challenge. Due to the steep biogeochemical gradients and the intensive structural and compositional heterogeneity, enhanced biogeochemical processing rates are inherent to aquatic interfaces. Nevertheless, the effective turnover depends strongly on the residence time distribution along the flow paths and in sections with particular biogeochemical milieus and reaction kinetics. Thus, identification and characterization of the highly complex flow patterns in and across aquatic interfaces are crucial to understand biogeochemical processing along exchange flow paths and to quantify transport across aquatic interfaces. Hydrodynamic and biogeochemical processes are closely coupled at aquatic interfaces. However, interface processing rates are not only enhanced compared to the adjacent compartments that they connect; also completely different reactions might occur if certain thresholds are exceeded or the biogeochemical milieu differs significantly from the adjacent environments. Single events, temporal variability and spatial heterogeneity might increase overall processing rates of aquatic interfaces and thus, should not be neglected when studying aquatic interfaces. Aquatic interfaces are key zones relevant for the ecological state of the entire ecosystem and thus, understanding interface functioning and controls is paramount for ecosystem management. The overall aim of this contribution is a general conceptual framework for aquatic interfaces that is applicable to a wide range of systems, scales and processes.

  12. Matched Interface and Boundary Method for Elasticity Interface Problems

    PubMed Central

    Wang, Bao; Xia, Kelin; Wei, Guo-Wei

    2015-01-01

    Elasticity theory is an important component of continuum mechanics and has had widely spread applications in science and engineering. Material interfaces are ubiquity in nature and man-made devices, and often give rise to discontinuous coefficients in the governing elasticity equations. In this work, the matched interface and boundary (MIB) method is developed to address elasticity interface problems. Linear elasticity theory for both isotropic homogeneous and inhomogeneous media is employed. In our approach, Lamé’s parameters can have jumps across the interface and are allowed to be position dependent in modeling isotropic inhomogeneous material. Both strong discontinuity, i.e., discontinuous solution, and weak discontinuity, namely, discontinuous derivatives of the solution, are considered in the present study. In the proposed method, fictitious values are utilized so that the standard central finite different schemes can be employed regardless of the interface. Interface jump conditions are enforced on the interface, which in turn, accurately determines fictitious values. We design new MIB schemes to account for complex interface geometries. In particular, the cross derivatives in the elasticity equations are difficult to handle for complex interface geometries. We propose secondary fictitious values and construct geometry based interpolation schemes to overcome this difficulty. Numerous analytical examples are used to validate the accuracy, convergence and robustness of the present MIB method for elasticity interface problems with both small and large curvatures, strong and weak discontinuities, and constant and variable coefficients. Numerical tests indicate second order accuracy in both L∞ and L2 norms. PMID:25914439

  13. Matched Interface and Boundary Method for Elasticity Interface Problems.

    PubMed

    Wang, Bao; Xia, Kelin; Wei, Guo-Wei

    2015-09-01

    Elasticity theory is an important component of continuum mechanics and has had widely spread applications in science and engineering. Material interfaces are ubiquity in nature and man-made devices, and often give rise to discontinuous coefficients in the governing elasticity equations. In this work, the matched interface and boundary (MIB) method is developed to address elasticity interface problems. Linear elasticity theory for both isotropic homogeneous and inhomogeneous media is employed. In our approach, Lamé's parameters can have jumps across the interface and are allowed to be position dependent in modeling isotropic inhomogeneous material. Both strong discontinuity, i.e., discontinuous solution, and weak discontinuity, namely, discontinuous derivatives of the solution, are considered in the present study. In the proposed method, fictitious values are utilized so that the standard central finite different schemes can be employed regardless of the interface. Interface jump conditions are enforced on the interface, which in turn, accurately determines fictitious values. We design new MIB schemes to account for complex interface geometries. In particular, the cross derivatives in the elasticity equations are difficult to handle for complex interface geometries. We propose secondary fictitious values and construct geometry based interpolation schemes to overcome this difficulty. Numerous analytical examples are used to validate the accuracy, convergence and robustness of the present MIB method for elasticity interface problems with both small and large curvatures, strong and weak discontinuities, and constant and variable coefficients. Numerical tests indicate second order accuracy in both L∞ and L2 norms.

  14. Dynamics of curved interfaces

    SciTech Connect

    Escudero, Carlos

    2009-08-15

    Stochastic growth phenomena on curved interfaces are studied by means of stochastic partial differential equations. These are derived as counterparts of linear planar equations on a curved geometry after a reparametrization invariance principle has been applied. We examine differences and similarities with the classical planar equations. Some characteristic features are the loss of correlation through time and a particular behavior of the average fluctuations. Dependence on the metric is also explored. The diffusive model that propagates correlations ballistically in the planar situation is particularly interesting, as this propagation becomes nonuniversal in the new regime.

  15. Virtual interface environment

    NASA Technical Reports Server (NTRS)

    Fisher, Scott S.

    1986-01-01

    A head-mounted, wide-angle, stereoscopic display system controlled by operator position, voice and gesture has been developed for use as a multipurpose interface environment. The system provides a multisensory, interactive display environment in which a user can virtually explore a 360-degree synthesized or remotely sensed environment and can viscerally interact with its components. Primary applications of the system are in telerobotics, management of large-scale integrated information systems, and human factors research. System configuration, application scenarios, and research directions are described.

  16. Adhesion at metal interfaces

    NASA Technical Reports Server (NTRS)

    Banerjea, Amitava; Ferrante, John; Smith, John R.

    1991-01-01

    A basic adhesion process is defined, the theory of the properties influencing metallic adhesion is outlined, and theoretical approaches to the interface problem are presented, with emphasis on first-principle calculations as well as jellium-model calculations. The computation of the energies of adhesion as a function of the interfacial separation is performed; fully three-dimensional calculations are presented, and universality in the shapes of the binding energy curves is considered. An embedded-atom method and equivalent-crystal theory are covered in the framework of issues involved in practical adhesion.

  17. Bidirectional Neural Interfaces

    PubMed Central

    Masters, Matthew R.; Thakor, Nitish V.

    2016-01-01

    A bidirectional neural interface is a device that transfers information into and out of the nervous system. This class of devices has potential to improve treatment and therapy in several patient populations. Progress in very-large-scale integration (VLSI) has advanced the design of complex integrated circuits. System-on-chip (SoC) devices are capable of recording neural electrical activity and altering natural activity with electrical stimulation. Often, these devices include wireless powering and telemetry functions. This review presents the state of the art of bidirectional circuits as applied to neuroprosthetic, neurorepair, and neurotherapeutic systems. PMID:26753776

  18. Multiple network interface core apparatus and method

    DOEpatents

    Underwood, Keith D [Albuquerque, NM; Hemmert, Karl Scott [Albuquerque, NM

    2011-04-26

    A network interface controller and network interface control method comprising providing a single integrated circuit as a network interface controller and employing a plurality of network interface cores on the single integrated circuit.

  19. Computational Studies of Structures and Dynamics of 1, 3-Dimethylimidazolim Salt Liquid and their Interfaces Using Polarizable Potential Models

    SciTech Connect

    Chang, Tsun-Mei; Dang, Liem X.

    2009-03-12

    The structures, thermodynamics, dynamical properties of bulk and air/liquid interfaces of three ionic liquids, 1,3-dimethylimidazolium [dmim]+, Cl-, Br-, and I- are studied using molecular dynamics techniques. In bulk melts, the radial distribution functions reveal a significant long-range structural correlation in these ionic liquids. From the angular distribution analysis, the imidazolium rings are found to lie parallel to each other at short distances, consistent with the structures observed in the crystal state. The single-ion dynamics are studied via mean-square-displacements, velocity and orientational correlation functions. The diffusion coefficients and reorientational times are found to be much smaller than H2O. We also observe that anion size plays an important role in the dynamics of ionic liquids. The computed density profiles of the ionic liquid/vapor interface exhibit oscillatory behavior, indicative of surface layering at the interface. Further analysis reveals that the [dmim]+ ions show preferred orientation at the interface with the ring parallel to the surface and methyl group attached to the ring pointing into the vapor phase. The computed surface tensions indicated small differences between these ionic liquids and are inline with recent experimental measurements. The calculated potential drops of these ionic liquids are found to be small and negative. These results could imply that the cation dipoles are likely to orient in the plane that parallel to the surface normal axis. This work was supported by the U.S. Department of Energy's (DOE) Office of Basic Energy Sciences, Chemical Sciences program. The Pacific Northwest National Laboratory is operated by Battelle for DOE.

  20. Mysteries at Ice Interfaces

    NASA Astrophysics Data System (ADS)

    Fain, Samuel C., Jr.

    1996-03-01

    Michael Faraday noted that ``two pieces of thawing ice, if put together, adhere and become one...the effect will take place in air, or in water, or in vacuo." Why? He proposed that ``a particle of water, which could retain the liquid state whilst touching ice only on one side, could not retain the liquid state if it were touched by ice on both sides."footnote M. Faraday, Proc. Roy. Soc. London 10, 440 (1860) The existence of special properties at interfaces of ice is generally agreed and has important environmental consequences.(J. G. Dash, H. Fu, and J. S. Wettlaufer, Rep. Prog. Phys. 58), 115 (1995) Why do different experiments infer different properties for this layer? Impurities and electric fields at the interfaces may be responsible for some of the variations in experimental results.footnote V. F. Petrenko, U. S. Army Cold Regions Research and Engineering Laboratory Report 94-22 (1994) Some background on the physical properties of ice will be discussed, including recent force microscopy measurements done at the University of Washington.footnote C.R. Slaughterbeck, E.W. Kukes, B. Pittenger, D.J. Cook, P.C. Williams, V.L. Eden, S.C. Fain, Jr., J. Vac. Sci. Technol. (in press) Supported by NSF Grant DMR-91-19701.

  1. Laparoscopic simulation interface

    DOEpatents

    Rosenberg, Louis B.

    2006-04-04

    A method and apparatus for providing high bandwidth and low noise mechanical input and output for computer systems. A gimbal mechanism provides two revolute degrees of freedom to an object about two axes of rotation. A linear axis member is coupled to the gimbal mechanism at the intersection of the two axes of rotation. The linear axis member is capable of being translated along a third axis to provide a third degree of freedom. The user object is coupled to the linear axis member and is thus translatable along the third axis so that the object can be moved along all three degrees of freedom. Transducers associated with the provided degrees of freedom include sensors and actuators and provide an electromechanical interface between the object and a digital processing system. Capstan drive mechanisms transmit forces between the transducers and the object. The linear axis member can also be rotated about its lengthwise axis to provide a fourth degree of freedom, and, optionally, a floating gimbal mechanism is coupled to the linear axis member to provide fifth and sixth degrees of freedom to an object. Transducer sensors are associated with the fourth, fifth, and sixth degrees of freedom. The interface is well suited for simulations of medical procedures and simulations in which an object such as a stylus or a joystick is moved and manipulated by the user.

  2. Mercury Shopping Cart Interface

    NASA Technical Reports Server (NTRS)

    Pfister, Robin; McMahon, Joe

    2006-01-01

    Mercury Shopping Cart Interface (MSCI) is a reusable component of the Power User Interface 5.0 (PUI) program described in another article. MSCI is a means of encapsulating the logic and information needed to describe an orderable item consistent with Mercury Shopping Cart service protocol. Designed to be used with Web-browser software, MSCI generates Hypertext Markup Language (HTML) pages on which ordering information can be entered. MSCI comprises two types of Practical Extraction and Report Language (PERL) modules: template modules and shopping-cart logic modules. Template modules generate HTML pages for entering the required ordering details and enable submission of the order via a Hypertext Transfer Protocol (HTTP) post. Shopping cart modules encapsulate the logic and data needed to describe an individual orderable item to the Mercury Shopping Cart service. These modules evaluate information entered by the user to determine whether it is sufficient for the Shopping Cart service to process the order. Once an order has been passed from MSCI to a deployed Mercury Shopping Cart server, there is no further interaction with the user.

  3. Use of EO-1 Advanced Land Imager (ALI) multispectral image data and real-time field sampling for water quality mapping in the Hirfanlı Dam Lake, Turkey.

    PubMed

    Kavurmacı, Murat; Ekercin, Semih; Altaş, Levent; Kurmaç, Yakup

    2013-08-01

    This paper focuses on the evaluation of water quality variations in Hirfanlı Water Reservoir, which is one of the most important water resources in Turkey, through EO-1 (Earth Observing-1) Advanced Land Imager (ALI) multispectral data and real-time field sampling. The study was materialized in 20 different sampling points during the overpass of the EO-1 ALI sensor over the study area. A multi-linear regression technique was used to explore the relationships between radiometrically corrected EO-1 ALI image data and water quality parameters: chlorophyll a, turbidity, and suspended solids. The retrieved and verified results show that the measured and estimated values of water quality parameters are in good agreement (R (2) >0.93). The resulting thematic maps derived from EO-1 multispectral data for chlorophyll a, turbidity, and suspended solids show the spatial distribution of the water quality parameters. The results indicate that the reservoir has average nutrient values. Furthermore, chlorophyll a, turbidity, and suspended solids values increased at the upstream reservoir and shallow coast of the Hirfanlı Water Reservoir.

  4. Intrinsic Chirality and Prochirality at Air/R-(+)- and S-(-)-Limonene Interfaces: Spectral Signatures with Interference Chiral Sum-Frequency Generation Vibrational Spectroscopy

    SciTech Connect

    Fu, Li; Zhang, Yun; Wei, Zhehao; Wang, Hongfei

    2014-06-04

    We report in this work detailed measurements on the chiral and achiral sum-frequency vibrational spectra in the C-H stretching vibration region (2800-3050cm-1) of the air/liquid interfaces of R-limonene and S-limonene, using the recently developed high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS). The achiral SFG spectra of R-limonene and S-limonene, as well as the equal amount (50/50) racemic mixture show that the enantiomers are with the same interfacial orientations. The interference chiral SFG spectra of the limonene enantiomers exhibit spectral signature from chiral response of the Cα-H stretching mode, and spectral signature from prochiral response of the CH2 asymmetric stretching mode, respectively. The chiral spectral feature of the Cα-H stretching mode changes sign from R-limonene to S-limonene, and disappears for the 50/50 racemic mixture. While the prochiral spectral feature of the CH2 asymmetric stretching mode is the same for R-limonene and S-limonene, and also surprisingly remains the same for the 50/50 racemic mixture. These results provided detail information in understanding the structure and chirality of molecular interfaces, and demonstrated the sensitivity and potential of SFG-VS as unique spectroscopic tool for chirality characterization and chiral recognition at the molecular interface.

  5. Thermal interface conductance across metal alloy-dielectric interfaces

    NASA Astrophysics Data System (ADS)

    Freedman, Justin P.; Yu, Xiaoxiao; Davis, Robert F.; Gellman, Andrew J.; Malen, Jonathan A.

    2016-01-01

    We present measurements of thermal interface conductance as a function of metal alloy composition. Composition spread alloy films of A uxC u1 -x and A uxP d1 -x solid solutions were deposited on single crystal sapphire substrates via dual electron-beam evaporation. High throughput measurements of thermal interface conductance across the (metal alloy)-sapphire interfaces were made by positional scanning of frequency domain thermoreflectance measurements to sample a continuum of Au atomic fractions (x ˜0 →1 ) . At a temperature of 300 K, the thermal interface conductance at the A uxC u1 -x -sapphire interfaces monotonically decreased from 197 ±39 MW m-2K-1 to 74 ±11 MW m-2K-1 for x =0 →0.95 ±0.02 and at the A uxP d1 -x -sapphire interfaces from 167 ±35 MW m-2K-1 to 60 ±10 MW m-2K-1 for x =0.03 →0.97 ±0.02 . To shed light on the phonon physics at the interface, a Diffuse Mismatch Model for thermal interface conductance with alloys is presented and agrees reasonably with the thermal interface conductance data.

  6. Low-Cost Evaluation of EO-1 Hyperion and ALI for Detection and Biophysical Characterization of Forest Logging in Amazonia (NCC5-481)

    NASA Technical Reports Server (NTRS)

    Asner, Gregory P.; Keller, Michael M.; Silva, Jose Natalino; Zweede, Johan C.; Pereira, Rodrigo, Jr.

    2002-01-01

    quantify both the presence and degree of structural disturbance caused by various logging regimes. Our quantitative assessment of Hyperion hyperspectral and ALI multi-spectral data for the detection and structural characterization of selective logging in Amazonia will benefit from data collected through an ongoing project run by the Tropical Forest Foundation, within which we have developed a study of the canopy and landscape biophysics of conventional and reduced-impact logging. We will add to our base of forest structural information in concert with an EO-1 overpass. Using a photon transport model inversion technique that accounts for non-linear mixing of the four biogeophysical indicators, we will estimate these parameters across a gradient of selective logging intensity provided by conventional and reduced impact logging sites. We will also compare our physical ly-based approach to both conventional (e.g., NDVI) and novel (e.g., SWIR-channel) vegetation indices as well as to linear mixture modeling methods. We will cross-compare these approaches using Hyperion and ALI imagers to determine the strengths and limitations of these two sensors for applications of forest biophysics. This effort will yield the first physical ly-based, quantitative analysis of the detection and intensity of selective logging in Amazonia, comparing hyperspectral and improved multi-spectral approaches as well as inverse modeling, linear mixture modeling, and vegetation index techniques.

  7. Evolution and circulation of type-2 vaccine-derived polioviruses in Nad Ali district of Southern Afghanistan during June 2009-February 2011.

    PubMed

    Sharif, Salmaan; Abbasi, Bilal Haider; Khurshid, Adnan; Alam, Muhammad Masroor; Shaukat, Shahzad; Angez, Mehar; Rana, Muhammad Suleman; Zaidi, Syed Sohail Zahoor

    2014-01-01

    Oral polio vaccine has been used successfully as a powerful tool to control the spread of wild polioviruses throughout the world; however, during replication in under immunized children, some vaccine viruses revert and acquire the neurovirulent phenotypic properties. In this study, we describe the evolution and circulation of Vaccine-Derived Polioviruses (VDPVs) in Helmand province of Afghanistan. We investigated 2646 AFP cases of Afghan children from June 2009-February 2011 and isolated 103 (04%) vaccine viruses, 45(1.7%) wild type polioviruses and six (0.22%) type 2 circulating vaccine-derived polioviruses (cVDPVs). These cVDPVs showed 97.7%-98.2% nucleotide and 98%-98.7% amino acid homology in VP1 region on comparison with Sabin type 2 reference strain. All these cVDPVs had two signature mutations of neurovirulent phenotypes and 12 additional mutations in P1 capsid region that might also have contributed to increase neurovirulence and replication. Phylogenetic analysis revealed that all these viruses were closely related and originated from previously reported Sabin like 2 virus from Pakistan which did not conform to the standard definition of VDPVs at that time. It was also observed that initial OPV dose was administered approximately 9 months prior to the collection of first stool specimen of index case. Our findings support that suboptimal surveillance and low routine immunization coverage have contributed to the emergence and spread of these viruses in Afghanistan. We therefore recommend high quality immunization campaigns not only in affected district Nad Ali but also in the bordering areas between Pakistan and Afghanistan to prevent the spread of cVDPVs.

  8. Development of Antisense Therapeutic and Imaging Agents to Detect and Suppress Inducible Nitric Oxide Synthase (iNOS) Expression in Acute Lung Injury (ALI)

    NASA Astrophysics Data System (ADS)

    Shen, Yuefei

    This dissertation focuses on the development and investigation of antisense imaging and therapeutic agents, combined with nanotechnology, to detect and suppress inducible nitric oxide synthase (iNOS) expression for the diagnosis and treatment of acute lung injury (ALI). To achieve this goal, several efforts were made. The first effort was the identification and characterization of high binding affinity antisense peptide nucleic acids (PNAs) and shell-crosslinked knedel-like nanoparticle (SCK)-PNA conjugates to the iNOS mRNA. Antisense binding sites on the iNOS mRNA were first mapped by a procedure for rapidly generating a library of antisense accessible sites on native mRNAs (MASL) which involves reverse transcription of whole cell mRNA extracts with a random oligodeoxynucleotide primer followed by mRNA-specific PCR. Antisense PNAs against the antisense accessible sites were accordingly synthesized and characterized. The second effort was the investigation of cationic shell crosslinked knedel-like nanoparticle (cSCK)-mediated siRNA delivery to suppress iNOS expression for the treatment of ALI. siRNA with its unique gene-specific properties could serve as a promising therapeutic agent, however success in this area has been challenged by a lack of efficient biocompatible transfection agents. cSCK with its nanometer size and positive charge previously showed efficient cellular delivery of phosphorothioate ODNs (oligodeoxynucleotides), plasmid DNA and PNA. Herein, cSCK showed good siRNA binding and facilitated efficient siRNA transfection in HeLa, a mouse macrophage cell line and other human cell lines. cSCK led to greater silencing efficiency than Lipofectamine 2000 in HeLa cells as determined by the viability following transfection with cytotoxic and non-cytotoxic siRNAs, as well in 293T and HEK cells, and was comparable in BEAS-2B and MCF10a cells. The third effort was the preparation of an iNOS imaging probe through electrostatic complexation between a radiolabeled

  9. XPI: The Xanadu Parameter Interface

    NASA Technical Reports Server (NTRS)

    White, N.; Barrett, P.; Oneel, B.; Jacobs, P.

    1992-01-01

    XPI is a table driven parameter interface which greatly simplifies both command driven programs such as BROWSE and XIMAGE as well as stand alone single-task programs. It moves all of the syntax and semantic parsing of commands and parameters out of the users code into common code and externally defined tables. This allows the programmer to concentrate on writing the code unique to the application rather than reinventing the user interface and for external graphical interfaces to interface with no changes to the command driven program. XPI also includes a compatibility library which allows programs written using the IRAF host interface (Mandel and Roll) to use XPI in place of the IRAF host interface.

  10. Human-computer interface

    DOEpatents

    Anderson, Thomas G.

    2004-12-21

    The present invention provides a method of human-computer interfacing. Force feedback allows intuitive navigation and control near a boundary between regions in a computer-represented space. For example, the method allows a user to interact with a virtual craft, then push through the windshield of the craft to interact with the virtual world surrounding the craft. As another example, the method allows a user to feel transitions between different control domains of a computer representation of a space. The method can provide for force feedback that increases as a user's locus of interaction moves near a boundary, then perceptibly changes (e.g., abruptly drops or changes direction) when the boundary is traversed.

  11. Porphyrins at interfaces

    NASA Astrophysics Data System (ADS)

    Auwärter, Willi; Écija, David; Klappenberger, Florian; Barth, Johannes V.

    2015-02-01

    Porphyrins and other tetrapyrrole macrocycles possess an impressive variety of functional properties that have been exploited in natural and artificial systems. Different metal centres incorporated within the tetradentate ligand are key for achieving and regulating vital processes, including reversible axial ligation of adducts, electron transfer, light-harvesting and catalytic transformations. Tailored substituents optimize their performance, dictating their arrangement in specific environments and mediating the assembly of molecular nanoarchitectures. Here we review the current understanding of these species at well-defined interfaces, disclosing exquisite insights into their structural and chemical properties, and also discussing methods by which to manipulate their intramolecular and organizational features. The distinct characteristics arising from the interfacial confinement offer intriguing prospects for molecular science and advanced materials. We assess the role of surface interactions with respect to electronic and physicochemical characteristics, and describe in situ metallation pathways, molecular magnetism, rotation and switching. The engineering of nanostructures, organized layers, interfacial hybrid and bio-inspired systems is also addressed.

  12. Nuclear data interface retrospective

    SciTech Connect

    Gray, Mark G

    2008-01-01

    The Nuclear Data Interface (NDI) code library and data formats are the standards for multigroup nuclear data at Los Alamos National Laboratory. NDI's analysis, design, implementation, testing, integration, and maintenance required a ten person-year and ongoing effort by the Nuclear Data Team. Their efforts provide a unique, contemporary experience in producing a standard component library. In reflection upon that experience at NDI's decennial, we have identified several factors critical to NDI's success: it addressed real problems with appropriate simplicity, it fully supported all users, it added extra value through the code to the raw nuclear data, and its team went the distance from analysis through maintenance. In this report we review these critical success factors and discuss their implications for future standardization projects.

  13. Brain-computer interfaces.

    PubMed

    Wolpaw, Jonathan R

    2013-01-01

    Brain-computer interfaces (BCIs) are systems that give their users communication and control capabilities that do not depend on muscles. The user's intentions are determined from activity recorded by electrodes on the scalp, on the cortical surface, or within the brain. BCIs can enable people who are paralyzed by amyotrophic lateral sclerosis (ALS), brainstem stroke, or other disorders to convey their needs and wishes to others, to operate word-processing programs or other software, or possibly to control a wheelchair or a neuroprosthesis. BCI technology might also augment rehabilitation protocols aimed at restoring useful motor function. With continued development and clinical implementation, BCIs could substantially improve the lives of those with severe disabilities.

  14. Standardized Spacecraft Onboard Interfaces

    NASA Technical Reports Server (NTRS)

    Smith, Joseph F.; Plummer, Chris; Plancke, Patrick

    2003-01-01

    The Consultative Committee for Space Data Systems (CCSDS), an international organization of national space agencies, is branching out to provide new standards to enhanced reuse of onboard spacecraft equipment and software. These Spacecraft Onboard Interface (SOIF) standards will be, in part, based on the well-known Internet protocols. This paper will provide a description of the SOIF work by describing three orthogonal views: the Services View that describes data communications services, the Interoperability view shows how to exchange data and messages between different spacecraft elements, and the Protocol view, that describes the SOIF protocols and services. We will also provide a description of the present state of the services that will be provided to SOIF users, and are the basis of the utility of these standards.

  15. Reaction Dynamics at Liquid Interfaces

    NASA Astrophysics Data System (ADS)

    Benjamin, Ilan

    2015-04-01

    The liquid interface is a narrow, highly anisotropic region, characterized by rapidly varying density, polarity, and molecular structure. I review several aspects of interfacial solvation and show how these affect reactivity at liquid/liquid interfaces. I specifically consider ion transfer, electron transfer, and SN2 reactions, showing that solvent effects on these reactions can be understood by examining the unique structure and dynamics of the liquid interface region.

  16. Reaction dynamics at liquid interfaces.

    PubMed

    Benjamin, Ilan

    2015-04-01

    The liquid interface is a narrow, highly anisotropic region, characterized by rapidly varying density, polarity, and molecular structure. I review several aspects of interfacial solvation and show how these affect reactivity at liquid/liquid interfaces. I specifically consider ion transfer, electron transfer, and SN2 reactions, showing that solvent effects on these reactions can be understood by examining the unique structure and dynamics of the liquid interface region.

  17. APST interfaces in LINCS

    SciTech Connect

    Fletcher, J.G.

    1995-07-01

    APST is an acronym for the four highest of the seven layers of the LINCS hierarchy of communication protocols: (from high to low) Application, Presentation, Session, and Transport. Routines in each but the lowest of these APST layers can utilize the facilities of any lower APST layer (normally, but not necessarily, the immediately next lower layer) by invoking various primitives (macros that in most cases are subroutine calls) defining the upper interface of the lower layer. So there are three APST interfaces: Presentation layer, used by the Application layer; Session layer, normally used by the Presentation layer; and Transport layer, normally used by the Session layer. Logically, each end of a stream (unidirectional sequence of transmitted information) is handled by three modules, one module each for the Presentation, Session, and Transport layers, and each of these modules deals with only that one end of that one stream. The internal workings of the layers, particularly the Transport layer, do not necessarily exhibit this same modularization; for example, the two oppositely directed streams between the same two ends (constituting an association) may interact within a layer. However, such interaction is an implementational detail of no direct interest to those utilizing the layer. The present document does not describe implementation, nor does it discuss in any detail how the modules employ packet headings and data formats to communicate with their partner modules at the other end of a stream. There being one logical module per end of stream is a characteristic only of the Presentation, Session, and Transport layers. An Application layer module usually manages several streams, orchestrating them to achieve some desired purpose. The modules of the layers (Network, Link, and Physical) below the APST layers each handle many streams, multiplexing them through the nodes and channels of the network to transmit them from their origins to their destinations.

  18. WWW to DICOM interface

    NASA Astrophysics Data System (ADS)

    Grevera, George J.; Feingold, Eric R.; Horii, Steven C.

    1996-05-01

    In this paper we discuss the implementation and use of a WWW interface to a DICOM PACS that allows users to select, move, and display images that are currently available in the PACS and to view their corresponding radiology reports. This system allows our users to query the archive from any workstation (such as Unix, DOS, and Mac) that supports a WWW browser. To use this system, the user first runs a WWW browser such as Mosaic, Netscape, or Lynx and specifies a URL on one of our Unix workstations. This URL refers to an HTML file that contains a query form. This query form contains a number of fields such as patient name and medical record number. The user may specify any or all fields as well as wildcards in fields such as the name field. Once the form is completed, the user presses a button to submit the request. The HTML form submits the query to a C program that executes on the Unix server. This program accepts as input the form field values that the user specified. This program then communicates with the archive via DICOM requests to determine those patients that match the search criteria. The user may then choose a patient which in turn causes the studies for this patient to be displayed. Finally, the user may select a study which causes those images to be retrieved from the archive and displayed via the Web browser. The result of this system is an easy to use interface to a DICOM PACS with the option to query and move images from the PACS. In summary, a system that integrates the ease of use of WWW browsers with a DICOM PACS is discussed. We are currently incorporating information from our RIS as well. This allows us to obtain extensive patient demographics, exam information, and textual radiological reports and associate this information with information from the PACS.

  19. Conformational preferences of DNA following damage by aristolochic acids: Structural and energetic insights into the different mutagenic potential of the ALI and ALII-N(6)-dA adducts.

    PubMed

    Kathuria, Preetleen; Sharma, Purshotam; Abendong, Minette N; Wetmore, Stacey D

    2015-04-21

    Aristolochic acids (AAI and AAII), produced by the Aristolochiaceae family of plants, are classified as group I (human) carcinogens by the International Agency for Research on Cancer. These acids are metabolized in cells to yield aristolactams (ALI and ALII, respectively), which further form bulky adducts with the purine nucleobases. Specifically, the adenine lesions are more persistent in cells and have been associated with chronic renal diseases and related carcinogenesis. To understand the structural basis of the nephrotoxicity induced by AAs, the ALI-N(6)-dA and ALII-N(6)-dA lesions are systematically studied using computational methods. Density functional theory calculations indicate that the aristolactam moiety intrinsically prefers a planar conformation with respect to adenine. Nucleoside and nucleotide models suggest that the anti and syn orientations about the glycosidic bond are isoenergetic for both adducts. Molecular dynamics simulations and free energy calculations reveal that the anti base-displaced intercalated conformation is the most stable conformer for both types of AL-N(6)-dA adducted DNA, which agrees with previous experimental work on the ALII-N(6)-dA adduct and thereby validates our approach. Interestingly, this conformer differs from the dominant conformations adopted by other N6-linked adenine lesions, including those derived from polycyclic aromatic hydrocarbons. Furthermore, the second most stable syn base-displaced intercalated conformation lies closer in energy to the anti base-displaced intercalated conformation for ALI-N(6)-dA compared to ALII-N(6)-dA. This indicates that a mixture of conformations may be detectable for ALI-N(6)-dA in DNA. If this enhanced conformational flexibility of double-stranded DNA persists when bound to a lesion-bypass polymerase, this provides a possible structural explanation for the previously observed greater nephrotoxic potential for the ALI versus ALII-N(6)-dA adduct. In addition, the structural

  20. Interfaces in perovskite solar cells.

    PubMed

    Shi, Jiangjian; Xu, Xin; Li, Dongmei; Meng, Qingbo

    2015-06-03

    The interfacial atomic and electronic structures, charge transfer processes, and interface engineering in perovskite solar cells are discussed in this review. An effective heterojunction is found to exist at the window/perovskite absorber interface, contributing to the relatively fast extraction of free electrons. Moreover, the high photovoltage in this cell can be attributed to slow interfacial charge recombination due to the outstanding material and interfacial electronic properties. However, some fundamental questions including the interfacial atomic and electronic structures and the interface stability need to be further clarified. Designing and engineering the interfaces are also important for the next-stage development of this cell.

  1. Interface-assisted molecular spintronics

    NASA Astrophysics Data System (ADS)

    Raman, Karthik V.

    2014-09-01

    Molecular spintronics, a field that utilizes the spin state of organic molecules to develop magneto-electronic devices, has shown an enormous scientific activity for more than a decade. But, in the last couple of years, new insights in understanding the fundamental phenomena of molecular interaction on magnetic surfaces, forming a hybrid interface, are presenting a new pathway for developing the subfield of interface-assisted molecular spintronics. The recent exploration of such hybrid interfaces involving carbon based aromatic molecules shows a significant excitement and promise over the previously studied single molecular magnets. In the above new scenario, hybridization of the molecular orbitals with the spin-polarized bands of the surface creates new interface states with unique electronic and magnetic character. This study opens up a molecular-genome initiative in designing new handles to functionalize the spin dependent electronic properties of the hybrid interface to construct spin-functional tailor-made devices. Through this article, we review this subject by presenting a fundamental understanding of the interface spin-chemistry and spin-physics by taking support of advanced computational and spectroscopy tools to investigate molecular spin responses with demonstration of new interface phenomena. Spin-polarized scanning tunneling spectroscopy is favorably considered to be an important tool to investigate these hybrid interfaces with intra-molecular spatial resolution. Finally, by addressing some of the recent findings, we propose novel device schemes towards building interface tailored molecular spintronic devices for applications in sensor, memory, and quantum computing.

  2. mREST Interface Specification

    NASA Technical Reports Server (NTRS)

    McCartney, Patrick; MacLean, John

    2012-01-01

    mREST is an implementation of the REST architecture specific to the management and sharing of data in a system of logical elements. The purpose of this document is to clearly define the mREST interface protocol. The interface protocol covers all of the interaction between mREST clients and mREST servers. System-level requirements are not specifically addressed. In an mREST system, there are typically some backend interfaces between a Logical System Element (LSE) and the associated hardware/software system. For example, a network camera LSE would have a backend interface to the camera itself. These interfaces are specific to each type of LSE and are not covered in this document. There are also frontend interfaces that may exist in certain mREST manager applications. For example, an electronic procedure execution application may have a specialized interface for configuring the procedures. This interface would be application specific and outside of this document scope. mREST is intended to be a generic protocol which can be used in a wide variety of applications. A few scenarios are discussed to provide additional clarity but, in general, application-specific implementations of mREST are not specifically addressed. In short, this document is intended to provide all of the information necessary for an application developer to create mREST interface agents. This includes both mREST clients (mREST manager applications) and mREST servers (logical system elements, or LSEs).

  3. Interface-assisted molecular spintronics

    SciTech Connect

    Raman, Karthik V.

    2014-09-15

    Molecular spintronics, a field that utilizes the spin state of organic molecules to develop magneto-electronic devices, has shown an enormous scientific activity for more than a decade. But, in the last couple of years, new insights in understanding the fundamental phenomena of molecular interaction on magnetic surfaces, forming a hybrid interface, are presenting a new pathway for developing the subfield of interface-assisted molecular spintronics. The recent exploration of such hybrid interfaces involving carbon based aromatic molecules shows a significant excitement and promise over the previously studied single molecular magnets. In the above new scenario, hybridization of the molecular orbitals with the spin-polarized bands of the surface creates new interface states with unique electronic and magnetic character. This study opens up a molecular-genome initiative in designing new handles to functionalize the spin dependent electronic properties of the hybrid interface to construct spin-functional tailor-made devices. Through this article, we review this subject by presenting a fundamental understanding of the interface spin-chemistry and spin-physics by taking support of advanced computational and spectroscopy tools to investigate molecular spin responses with demonstration of new interface phenomena. Spin-polarized scanning tunneling spectroscopy is favorably considered to be an important tool to investigate these hybrid interfaces with intra-molecular spatial resolution. Finally, by addressing some of the recent findings, we propose novel device schemes towards building interface tailored molecular spintronic devices for applications in sensor, memory, and quantum computing.

  4. Multimodal human-machine interface based on a brain-computer interface and an electrooculography interface.

    PubMed

    Iáñez, Eduardo; Ùbeda, Andrés; Azorín, José M

    2011-01-01

    This paper describes a multimodal interface that combines a Brain-Computer Interface (BCI) with an electrooculography (EOG) interface. The non-invasive spontaneous BCI registers the electrical brain activity through surface electrodes. The EOG interface detects the eye movements through electrodes placed on the face around the eyes. Both kind of signals are registered together and processed to obtain the mental task that the user is thinking and the eye movement performed by the user. Both commands (mental task and eye movement) are combined in order to move a dot in a graphic user interface (GUI). Several experimental tests have been made where the users perform a trajectory to get closer to some targets. To perform the trajectory the user moves the dot in a plane with the EOG interface and using the BCI the dot changes its height.

  5. Overview of Graphical User Interfaces.

    ERIC Educational Resources Information Center

    Hulser, Richard P.

    1993-01-01

    Discussion of graphical user interfaces for online public access catalogs (OPACs) covers the history of OPACs; OPAC front-end design, including examples from Indiana University and the University of Illinois; and planning and implementation of a user interface. (10 references) (EA)

  6. The interface engine: experimental consequences.

    PubMed

    Tauer, Klaus; Kozempel, Steffen; Rother, Gudrun

    2007-08-15

    A light microscopy study confirms spontaneous emulsification at the quiescent, thermally equilibrated interface between pure oil and pure water during the chemical equilibration period. The process is qualitatively explained within the frame of the classical nucleation theory assuming a mixed interface layer between the two liquids in contact allowing supersaturation.

  7. In Situ Adsorption Studies at the Solid/Liquid Interface:Characterization of Biological Surfaces and Interfaces Using SumFrequency Generation Vibrational Spectroscopy, Atomic Force Microscopy,and Quartz Crystal Microbalance

    SciTech Connect

    Phillips, Diana Christine

    2006-01-01

    Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and quartz crystal microbalance (QCM) have been used to study the molecular surface structure, surface topography and mechanical properties, and quantitative adsorbed amount of biological molecules at the solid-liquid interface. The molecular-level behavior of designed peptides adsorbed on hydrophobic polystyrene and hydrophilic silica substrates has been examined as a model of protein adsorption on polymeric biomaterial surfaces. Proteins are such large and complex molecules that it is difficult to identify the features in their structure that lead to adsorption and interaction with solid surfaces. Designed peptides which possess secondary structure provide simple model systems for understanding protein adsorption. Depending on the amino acid sequence of a peptide, different secondary structures (α-helix and β-sheet) can be induced at apolar (air/liquid or air/solid) interfaces. Having a well-defined secondary structure allows experiments to be carried out under controlled conditions, where it is possible to investigate the affects of peptide amino acid sequence and chain length, concentration, buffering effects, etc. on adsorbed peptide structure. The experiments presented in this dissertation demonstrate that SFG vibrational spectroscopy can be used to directly probe the interaction of adsorbing biomolecules with a surface or interface. The use of well designed model systems aided in isolation of the SFG signal of the adsorbing species, and showed that surface functional groups of the substrate are sensitive to surface adsorbates. The complementary techniques of AFM and QCM allowed for deconvolution of the effects of surface topography and coverage from the observed SFG spectra. Initial studies of biologically relevant surfaces are also presented: SFG spectroscopy was used to study the surface composition of common soil bacteria for use in bioremediation of nuclear waste.

  8. Colloids at Curved Fluid Interfaces

    NASA Astrophysics Data System (ADS)

    Stebe, Kathleen

    2016-11-01

    Fluid interfaces are remarkable sites for colloidal assembly. When a colloid attaches to a fluid interface, it distorts a region around it; this distortion has an associated capillary energy, the product of its area and interfacial tension. The particle's capillary energy depends on the local interface curvature. By molding the interface, we can define curvature fields that drive microparticles along pre-determined paths. This example captures the emergent nature of the interactions. We discuss curvature fields as analogues to external electro-magnetic fields, and define curvatures that drive particles to well-defined locations, and to equilibrium sites far from boundaries. Particle-particle and particle-curvature interactions can guide particles into structures via interaction among many particles. This work demonstrates the potential importance of curvature capillary interactions in schemes to make reconfigurable materials, since interfaces and their associated capillary energy landscapes can be readily reconfigured. Analogies in other soft systems will be described. Support acknowledged from NSF DMR 1607878.

  9. Next Generation Search Interfaces

    NASA Astrophysics Data System (ADS)

    Roby, W.; Wu, X.; Ly, L.; Goldina, T.

    2015-09-01

    Astronomers are constantly looking for easier ways to access multiple data sets. While much effort is spent on VO, little thought is given to the types of User Interfaces we need to effectively search this sort of data. For instance, an astronomer might need to search Spitzer, WISE, and 2MASS catalogs and images then see the results presented together in one UI. Moving seamlessly between data sets is key to presenting integrated results. Results need to be viewed using first class, web based, integrated FITS viewers, XY Plots, and advanced table display tools. These components should be able to handle very large datasets. To make a powerful Web based UI that can manage and present multiple searches to the user requires taking advantage of many HTML5 features. AJAX is used to start searches and present results. Push notifications (Server Sent Events) monitor background jobs. Canvas is required for advanced result displays. Lesser known CSS3 technologies makes it all flow seamlessly together. At IPAC, we have been developing our Firefly toolkit for several years. We are now using it to solve this multiple data set, multiple queries, and integrated presentation problem to create a powerful research experience. Firefly was created in IRSA, the NASA/IPAC Infrared Science Archive (http://irsa.ipac.caltech.edu). Firefly is the core for applications serving many project archives, including Spitzer, Planck, WISE, PTF, LSST and others. It is also used in IRSA's new Finder Chart and catalog and image displays.

  10. User interface enhancement report

    NASA Technical Reports Server (NTRS)

    Badler, N. I.; Gangel, J.; Shields, G.; Fala, G.

    1985-01-01

    The existing user interfaces to TEMPUS, Plaid, and other systems in the OSDS are fundamentally based on only two modes of communication: alphanumeric commands or data input and grapical interaction. The latter are especially suited to the types of interaction necessary for creating workstation objects with BUILD and with performing body positioning in TEMPUS. Looking toward the future application of TEMPUS, however, the long-term goals of OSDS will include the analysis of extensive tasks in space involving one or more individuals working in concert over a period of time. In this context, the TEMPUS body positioning capability, though extremely useful in creating and validating a small number of particular body positions, will become somewhat tedious to use. The macro facility helps somewhat, since frequently used positions may be easily applied by executing a stored macro. The difference between body positioning and task execution, though subtle, is important. In the case of task execution, the important information at the user's level is what actions are to be performed rather than how the actions are performed. Viewed slightly differently, the what is constant over a set of individuals though the how may vary.

  11. Power User Interface

    NASA Technical Reports Server (NTRS)

    Pfister, Robin; McMahon, Joe

    2006-01-01

    Power User Interface 5.0 (PUI) is a system of middleware, written for expert users in the Earth-science community, PUI enables expedited ordering of data granules on the basis of specific granule-identifying information that the users already know or can assemble. PUI also enables expert users to perform quick searches for orderablegranule information for use in preparing orders. PUI 5.0 is available in two versions (note: PUI 6.0 has command-line mode only): a Web-based application program and a UNIX command-line- mode client program. Both versions include modules that perform data-granule-ordering functions in conjunction with external systems. The Web-based version works with Earth Observing System Clearing House (ECHO) metadata catalog and order-entry services and with an open-source order-service broker server component, called the Mercury Shopping Cart, that is provided separately by Oak Ridge National Laboratory through the Department of Energy. The command-line version works with the ECHO metadata and order-entry process service. Both versions of PUI ultimately use ECHO to process an order to be sent to a data provider. Ordered data are provided through means outside the PUI software system.

  12. Aquatic Acoustic Metrics Interface

    SciTech Connect

    2012-12-18

    Fishes and marine mammals may suffer a range of potential effects from exposure to intense underwater sound generated by anthropogenic activities such as pile driving, shipping, sonars, and underwater blasting. Several underwater sound recording (USR) devices have been built to acquire samples of the underwater sound generated by anthropogenic activities. Software becomes indispensable for processing and analyzing the audio files recorded by these USRs. The new Aquatic Acoustic Metrics Interface Utility Software (AAMI) is specifically designed for analysis of underwater sound recordings to provide data in metrics that facilitate evaluation of the potential impacts of the sound on aquatic animals. In addition to the basic functions, such as loading and editing audio files recorded by USRs and batch processing of sound files, the software utilizes recording system calibration data to compute important parameters in physical units. The software also facilitates comparison of the noise sound sample metrics with biological measures such as audiograms of the sensitivity of aquatic animals to the sound, integrating various components into a single analytical frame.

  13. Centennial-scale vegetation and climate changes in the Middle Atlas, Morocco: new insights from multi-proxy investigations at Lake Sidi Ali

    NASA Astrophysics Data System (ADS)

    Fletcher, William; Campbell, Jennifer; Joannin, Sebastien; Mischke, Steffen; Zielhofer, Christoph; de Batist, Marc; Mikdad, Abdes

    2016-04-01

    The karstic lakes of the Middle Atlas, Morocco, represent a valuable archive of environmental and climatic change for Northwest Africa. Here we present the results of centennial-scale palynological and charcoal analyses as part of a multiproxy palaeolimnological study of sediment cores from Lake Sidi Ali in the Middle Atlas, Morocco (33° 03 N, 05° 00 W; 2,080 m a.s.l.). Supported by absolute dating including 23 more than twenty AMS 14C dates on pollen concentrates, the record covers the entire Holocene and offers insights into vegetation and climate change at a regionally unprecedented centennial-scale. Pollen assemblages are dominated by steppic herbs, evergreen oaks (Quercus), junipers (Cupressaceae) and Atlantic cedar (Cedrus atlantica). A long-term evolution of the montane vegetation is recorded, reflecting progressive changes in the dominant arboreal taxa and leading to the full establishment of the emblematic cedar forests of the area during the mid-Holocene by 6000 cal BP. Orbital-scale changes in seasonality and growing season moisture availability linked to declining summer insolation are implicated, with a transition from (a) warm, dry summers associated with summer drought tolerant taxa especially evergreen Quercus, high algal productivity in the lake, and high background levels of microcharcoal reflecting distant fire activity during the early Holocene, to (b) cool, relatively humid summers with dominance of montane conifers, declining algal productivity in the lake, and episodic local fire activity during the mid- to late Holocene. Superimposed on the long-term environmental changes are recurrent centennial-scale fluctuations in vegetation composition, reflecting competitive dynamics between the major taxa, initially between steppic and arboreal elements, and later between the major tree taxa. Parallels with hydrological proxies including stable O and C isotopes suggest common responses to climatic drivers (fluctuations in moisture sources and

  14. Petrochemistry of ultrapotassic tephrites and associated cognate plutonic xenoliths with carbonatite affinities from the late Quaternary Qa’le Hasan Ali maars, central Iran

    NASA Astrophysics Data System (ADS)

    Saadat, S.; Stern, C. R.; Moradian, A.

    2014-08-01

    The Quaternary Qa’le Hasan Ali (QHA) maars in central Iran occur at the intersection of the north-south Nayband fault, which defines the western boundary of the Lut micro-continental block, and a system of northwest-southeast faults, subparallel to the Zagros suture zone, that formed during the Arabian-Eurasian collision. These post-collisional maars intrude Eocene volcanic rocks of the Urumieh-Dokhtar magmatic belt, which was generated by the subduction of Neotethys oceanic lithosphere below Iran. The highly potassic, Ti-phlogopite + Mg-rich (Fo89-92) olivine + diopside-augite + aegirine-augite basanite tephrites forming the tuff rims of the QHA maars contain tephrite-coated plutonic xenoliths, some of which are interpreted as co-genetic with the tephrites based on their similar mineralogy and Sr isotopic composition (87Sr/86Sr = 0.70590). Cognate plutonic xenoliths have up to ∼20 vol% calcite, considered to be magmatic calcite because of (1) its grain size, which is similar to feldspars and aegirine-augite pyroxenes in these rocks, (2) the occurrence of fine-grained inclusions of pyroxene and apatite within these calcite grains, and (3) the similarity of the Sr-isotopic composition of this calcite with the other minerals in these rocks. The fact that the magmatic calcite has remained intact and did not volatilize during the transport of these xenoliths to the surface in the hot tephrite magma implies a short transit time, indicating that they are samples of a shallow plutonic complex, as does the presence of anorthoclase in these plutonic xenoliths. Their high modal proportion of magmatic calcite suggests that this shallow plutonic complex has affinities with carbonatites. The magmatic calcite-bearing plutonic xenoliths have high LREE/HREE ratios and contain REE-rich allanite (with up to ∼20 wt% LREE) and britholite (∼60 wt% LREE) that make up ∼3 modal percent of the most calcite-rich samples. Similar to many post-collisional highly potassic rocks

  15. Le champ critique de claquage de films d'oxyde de polyphénylène réalisés par voie électrochimique

    NASA Astrophysics Data System (ADS)

    Adohi, B.; Gosse, J. P.; Gosse, B.

    1991-10-01

    The electrical breakdown of thin films of polyphenylene oxide electrochemically deposited on stainless steel plane substrates has been studied. First it was examined the dependence of the medium surrounding the dielectric and the electrodes (nature, hydrostatic pressure) on the breakdown voltage and on its statistical distribution. Between sphere and plane electrodes, it appears that even for pressurified gases, breakdown of the film is caused by the gas breakdown. We have analysed the discharges occurring at atmosphere pressure in the test cell. Breakdown of the film occurred when the electric field due to the charge deposited on its surface was about 230 V/μm. We have also studied self-healing capacitors with PPO as a dielectric, and determined the life-time of this material. On a étudié le claquage électrique de films minces d'oxyde de polyphénylène de quelques microns d'épaisseur déposés par voie électrochimique sur un plan en acier inoxydable. L'étude a d'abord été faite en rampe de tension continue dans la géométrie d'électrodes sphèreplan, en fonction du milieu ambiant liquide ou gazeux. L'influence de la pression sur la rigidité diélectrique du matériau, les distributions statistiques de Weibull et les cratères formés au moment du claquage, dans les différents milieux et dans les deux polarités de l'électrode sphérique montrent que le claquage du matériau est causé par des décharges qui se produisent dans le milieu environnant. A partir de l'analyse quantitative de ces décharges, on propose comme critère de caractérisation de la rupture d'un matériau sounmis aux décharges, le champ créé au moment de la rupture par les charges déposées à sa surface. On a réalisé ensuite des échantillons plans << autocicatrisables >> par dépôt de couches minces d'aluminium (quelques milliers d'Å d'épaisseur) sur le film de PPO. On étudie dans cette configuration la durée de vie du matériau.

  16. Diffusion, diffraction des neutrons en temps réel et études réalisées in situ

    NASA Astrophysics Data System (ADS)

    Isnard, O.

    2003-02-01

    La diffusion des neutrons est une technique particulièrement efficace pour l'analyse en temps réel des processus réactionnels dans la matière. La diffraction de neutrons in situ a été développée très tôt sur les sources à haut flux tel que l'Institut Laue Langevin. Ces études nécessitent un flux de neutrons important et un détecteur couvrant un domaine angulaire le plus grand possible. Les neutrons offrent la spécificité d'être très peu absorbés par nombre de matériaux, cette faible absorption fait de la diffusion neutronique un excellent outil pour sonder la matière en volume et de manière non destructive. Cela permet en particulier d'utiliser des environnements d'échantillons complexes tout en conservant un flux raisonnable. La diffusion de neutrons en temps réel est donc très largement utilisée par diverses communautés scientifiques : sciences des matériaux, physiciens, chimistes... L'objet de ce cours est de donner les paramètres importants pour ce type d'étude et d'illustrer le propos à l'aide d'exemples pris dans des domaines scientifiques divers : électrochimie, magnétisme, métallurgie, chimie du solide. Après avoir présenté quelques repères méthodologiques sur les méthodes d'acquisition de données, des exemples montreront le fort potentiel de la diffusion neutronique en temps réel pour l'étude de la matière dans des conditions dynamiques. Enfin, nous donnerons aussi quelques conseils pour la visualisation, le dépouillement et l'analyse de ce type d'expérience. La diffusion des neutrons sur poudre est actuellement très bien adaptée aux études réalisées in situ. Cependant, nous verrons que la faisabilité d'études in situ s'étend à d'autres techniques expérimentales telles que la diffusion des neutrons aux petits angles et même la diffusion sur monocristal qui est en plein renouveau.

  17. Review on a Traditional Herbal Medicine, Eurycoma longifolia Jack (Tongkat Ali): Its Traditional Uses, Chemistry, Evidence-Based Pharmacology and Toxicology.

    PubMed

    Rehman, Shaheed Ur; Choe, Kevin; Yoo, Hye Hyun

    2016-03-10

    Eurycoma longifolia Jack (known as tongkat ali), a popular traditional herbal medicine, is a flowering plant of the family Simaroubaceae, native to Indonesia, Malaysia, Vietnam and also Cambodia, Myanmar, Laos and Thailand. E. longifolia, is one of the well-known folk medicines for aphrodisiac effects as well as intermittent fever (malaria) in Asia. Decoctions of E. longifolia leaves are used for washing itches, while its fruits are used in curing dysentery. Its bark is mostly used as a vermifuge, while the taproots are used to treat high blood pressure, and the root bark is used for the treatment of diarrhea and fever. Mostly, the roots extract of E. longifolia are used as folk medicine for sexual dysfunction, aging, malaria, cancer, diabetes, anxiety, aches, constipation, exercise recovery, fever, increased energy, increased strength, leukemia, osteoporosis, stress, syphilis and glandular swelling. The roots are also used as an aphrodisiac, antibiotic, appetite stimulant and health supplement. The plant is reported to be rich in various classes of bioactive compounds such as quassinoids, canthin-6-one alkaloids, β-carboline alkaloids, triterpene tirucallane type, squalene derivatives and biphenyl neolignan, eurycolactone, laurycolactone, and eurycomalactone, and bioactive steroids. Among these phytoconstituents, quassinoids account for a major portion of the E. longifolia root phytochemicals. An acute toxicity study has found that the oral Lethal Dose 50 (LD50) of the alcoholic extract of E. longifolia in mice is between 1500-2000 mg/kg, while the oral LD50 of the aqueous extract form is more than 3000 mg/kg. Liver and renal function tests showed no adverse changes at normal daily dose and chronic use of E. longifolia. Based on established literature on health benefits of E. longifolia, it is important to focus attention on its more active constituents and the constituents' identification, determination, further development and most importantly, the

  18. Multimodal Neuroelectric Interface Development

    NASA Technical Reports Server (NTRS)

    Trejo, Leonard J.; Wheeler, Kevin R.; Jorgensen, Charles C.; Totah, Joseph (Technical Monitor)

    2001-01-01

    This project aims to improve performance of NASA missions by developing multimodal neuroelectric technologies for augmented human-system interaction. Neuroelectric technologies will add completely new modes of interaction that operate in parallel with keyboards, speech, or other manual controls, thereby increasing the bandwidth of human-system interaction. We recently demonstrated the feasibility of real-time electromyographic (EMG) pattern recognition for a direct neuroelectric human-computer interface. We recorded EMG signals from an elastic sleeve with dry electrodes, while a human subject performed a range of discrete gestures. A machine-teaming algorithm was trained to recognize the EMG patterns associated with the gestures and map them to control signals. Successful applications now include piloting two Class 4 aircraft simulations (F-15 and 757) and entering data with a "virtual" numeric keyboard. Current research focuses on on-line adaptation of EMG sensing and processing and recognition of continuous gestures. We are also extending this on-line pattern recognition methodology to electroencephalographic (EEG) signals. This will allow us to bypass muscle activity and draw control signals directly from the human brain. Our system can reliably detect P-rhythm (a periodic EEG signal from motor cortex in the 10 Hz range) with a lightweight headset containing saline-soaked sponge electrodes. The data show that EEG p-rhythm can be modulated by real and imaginary motions. Current research focuses on using biofeedback to train of human subjects to modulate EEG rhythms on demand, and to examine interactions of EEG-based control with EMG-based and manual control. Viewgraphs on these neuroelectric technologies are also included.

  19. Nanoparticle Assemblies at Fluid Interfaces

    SciTech Connect

    Russell, Thomas P.

    2015-03-10

    A systematic study of the structure and dynamics of nanoparticles (NP) and NP-surfactants was performed. The ligands attached to both the NPs and NP-surfactants dictate the manner in which the nanoscopic materials assemble at fluid interfaces. Studies have shown that a single layer of the nanoscpic materials form at the interface to reduce the interactions between the two immiscible fluids. The shape of the NP is, also, important, where for spherical particles, a disordered, liquid-like monolayer forms, and, for nanorods, ordered domains at the interface is found and, if the monolayers are compressed, the orientation of the nanorods with respect to the interface can change. By associating end-functionalized polymers to the NPs assembled at the interface, NP-surfactants are formed that increase the energetic gain in segregating each NP at the interface which allows the NP-surfactants to jam at the interface when compressed. This has opened the possibility of structuring the two liquids by freezing in shape changes of the liquids.

  20. Dynamics of interfaces in superconductors

    SciTech Connect

    Dorsey, A.T. )

    1994-08-01

    The dynamics of an interface between the normal and superconducting phases under nonstationary external conditions is studied within the framework of the time-dependent Ginzburg-Landau equations of superconductivity, modified to include thermal fluctuations. An equation of motion for the interface is derived in two steps. First, the method of matched asymptotic expansions is used to derive a diffusion equation for the magnetic field in the normal phase, with nonlinear boundary conditions at the interface. These boundary conditions are a continuity equation which relates the gradient of the field at the interface to the normal velocity of the interface and a modified Gibbs-Thomson boundary condition for the field at the interface. Second, the boundary integral method is used to integrate out the magnetic field in favor of an equation of motion for the interface. This equation of motion, which is highly nonlinear and nonlocal, exhibits a diffusive instability (the Mullins-Sekerka instability) when the superconducting phase expands into the normal phase (i.e., when the external field is reduced below the critical field). In the limit of infinite diffusion constant the equation of motion becomes local in time and can be derived variationally from a static energy functional which includes the bulk-free energy difference between the two phases, the interfacial energy, and a long range self-interaction of the interface of the Biot-Savart form. In this limit the dynamics is identical to the interfacial dynamics of ferrofluid domains recently proposed by S.A. Langer et al. As shown by these authors, the Biot-Savart interaction leads to mechanical instabilities of the interface, resulting in highly branched labyrinthine patterns. The application of these ideas to the study of labyrinthine patterns in the intermediate state of type-I superconductors is briefly discussed. 29 refs.

  1. Nano-size Effect of Interface Energy and Its Effect on Interface Fracture

    SciTech Connect

    Liang, L. H.; You, X. M.; Ma, H. S.; Wei, Y. G.

    2010-05-21

    An analytical model about size-dependent interface energy of metal/ceramic interfaces in nanoscale is developed by introducing both the chemical energy and the structure stain energy contributions. The dependence of interface energy on the interface thickness is determined by the melting enthalpy, the molar volume, and the shear modulus of two materials composing the interfaces, etc. The analytic prediction of the interface energy and the atomic scale simulation of the interface fracture strength are compared with each other for Ag/MgO and Ni/Al{sub 2}O{sub 3} interfaces, the fracture strength of the interface with the lower chemical interface energy is found to be larger. The potential of Ag/MgO interface related to the interface energy is calculated, and the interface stress and the interface fracture strength are estimated further. The effect of the interface energy on the interface strength and the behind mechanism are discussed.

  2. Hopping diffusion across material interfaces

    NASA Astrophysics Data System (ADS)

    Deppe, J.; Wallis, R. F.; Balkanski, M.

    1993-11-01

    We generalize a one-dimensional lattice-gas model of particle diffusion across material interfaces to include a finite-width interface region, and an energy barrier at the interface. We use overvoltage measurements on InSe and dielectric loss measurements on B 2O+ 3-0.5 Li 2O-0.15 Li 2SO 4 to determine the hopping rates in the two materials. Numerical and analytical results for the particle density versus position are presented for representative values of the energy barrier and a range of hopping rates. The presence of the energy barrier is found to be a dominant factor in the problem.

  3. Fiber-matrix interface failures

    NASA Technical Reports Server (NTRS)

    Rabenberg, Lew; Marcus, Harris L.; Park, Hun Sub; Zong, Gui Sheng; Brown, Lloyd D.

    1989-01-01

    Interface fractures of aluminum-graphite composites under transverse loading are expected to occur within the graphite fibers, but very near the interface. Residual stresses in aluminum, reinforced with the new high modulus pitch-based fibers, are much lower than would be expected based on simple elasticity calculations. The excess stress may be relaxed by shearing internal to the fibers or at the interface rather than by plastic flow of the matrix. The internal shearing also occurs during repeated thermal cycling of these composites; the fibers are repeatedly intruded, then extruded, during repeated temperature excursions.

  4. Superconducting interfaces between insulating oxides.

    PubMed

    Reyren, N; Thiel, S; Caviglia, A D; Kourkoutis, L Fitting; Hammerl, G; Richter, C; Schneider, C W; Kopp, T; Rüetschi, A-S; Jaccard, D; Gabay, M; Muller, D A; Triscone, J-M; Mannhart, J

    2007-08-31

    At interfaces between complex oxides, electronic systems with unusual electronic properties can be generated. We report on superconductivity in the electron gas formed at the interface between two insulating dielectric perovskite oxides, LaAlO3 and SrTiO3. The behavior of the electron gas is that of a two-dimensional superconductor, confined to a thin sheet at the interface. The superconducting transition temperature of congruent with 200 millikelvin provides a strict upper limit to the thickness of the superconducting layer of congruent with 10 nanometers.

  5. ARINC 653 Interface in RTEMS

    NASA Astrophysics Data System (ADS)

    Rufino, J.; Filipe, S.; Coutinho, M.; Santos, S.; Windsor, J.

    2007-08-01

    The ARINC 653 specification is assuming a key role in the provision of a standard operating system interface for safety-critical applications in the aeronautic market and it is foreseen to acquire a similar status on the space market. The ARINC 653 application interface is inde- pendent from the underlying hardware and from a given operating system implementation. This paper describes how RTEMS, the Real-Time Executive for Multiproces- sor Systems, can be adapted to offer the application interface and the functionality required by the ARINC 653 standard. The use of RTEMS is highly relevant given its qualification for on-board software of unmanned space programs.

  6. Aptian Paleoclimates and Identification of an OAE1a Equivalent in Shallow Marine Environments of the Southern Tethyan Margin: The Bir Oum Ali Section, Northern Chott Chain, Southern Tunisia

    NASA Astrophysics Data System (ADS)

    Hfaiedh, R.; Godet, A.; Arnaud-Vanneau, A.; Zghal, I.; Arnaud, H.; Ouali, J.

    2015-12-01

    Alternations between siliciclastic, carbonate and evaporitic sedimentary systems, as recorded in the Aptian mixed succession of southern Tunisia, reflect profound paleoceanographic, paleoclimatic and tectonic changes in this area of the southern Tethyan margin. Whereas the early Aptian is interpreted as having been dominated by slightly humid conditions, the onset of a gypsiferous sedimentation near the early to late Aptian boundary is associated with the appearance of palygorskite and sepiolite, which supports the installation of arid conditions in the study area. The evaporitic sedimentation may have also been promoted by the peculiar tectonic setting of the Bir Oum Ali area during the Aptian, where local subsidence may have been tectonically-enhanced in relation to the opening of northern and central Atlantic. Chemostratigraphic (δ13C) correlation of the Bir Oum Ali succession with other peri-Tethyan regions complements biostratigraphic findings, and indicates that a potential expression of the Oceanic Anoxic Event (OAE) 1a may be preserved in this area of Tunisia. Although the characteristic negative spike in δ13C values located at the base of this event is not recognized in the present study, a subsequent, large positive excursion is of similar amplitude and absolute values to those reported from other peri-tethyan regions. This comparison supports the identification of isotopic segments C4 to C7 of the OAE1a, during which the dominance of macroalgae over other benthic organisms is observed at Bir Oum Ali. The absence of the negative spike may be linked to either non preservation or non deposition: the OAE1a occurred in a global transgressive context, and since the study area was located in the innermost part of the southern Tethyan margin during most of the Aptian, stratigraphic hiatuses may have been longer than in other regions of the Tethys.

  7. A comparative assessment of cigarette smoke aerosols using an in vitro air–liquid interface cytotoxicity test

    PubMed Central

    Thorne, David; Dalrymple, Annette; Dillon, Deborah; Duke, Martin; Meredith, Clive

    2015-01-01

    Abstract This study describes the evaluation of a modified air-liquid interface BALB/c 3T3 cytotoxicity method for the assessment of smoke aerosols in vitro. The functionality and applicability of this modified protocol was assessed by comparing the cytotoxicity profiles from eight different cigarettes. Three reference cigarettes, 1R5F, 3R4F and CORESTA Monitor 7 were used to put the data into perspective and five bespoke experimental products were manufactured, ensuring a balanced and controlled study. Manufactured cigarettes were matched for key variables such as nicotine delivery, puff number, pressure drop, ventilation, carbon monoxide, nicotine free dry particulate matter and blend, but significantly modified for vapor phase delivery, via the addition of two different types and quantities of adsorptive carbon. Specifically manufacturing products ensures comparisons can be made in a consistent manner and allows the research to ask targeted questions, without confounding product variables. The results demonstrate vapor-phase associated cytotoxic effects and clear differences between the products tested and their cytotoxic profiles. This study has further characterized the in vitro vapor phase biological response relationship and confirmed that the biological response is directly proportional to the amount of available vapor phase toxicants in cigarette smoke, when using a Vitrocell® VC 10 exposure system. This study further supports and strengthens the use of aerosol based exposure options for the appropriate analysis of cigarette smoke induced responses in vitro and may be especially beneficial when comparing aerosols generated from alternative tobacco aerosol products. PMID:26339773

  8. Sandia ATM SONET Interface Logic

    SciTech Connect

    Kitta, Joseph P.

    1994-07-21

    SASIL is used to program the EPLD's (Erasable Programmable Logic Devices) and PAL's (Programmable Array Logic) that make up a large percentage of the Sandia ATM SONET Interface (OC3 version) for the INTEL Paragon.

  9. SKITTER/implement mechanical interface

    NASA Technical Reports Server (NTRS)

    Cash, John Wilson, III; Cone, Alan E.; Garolera, Frank J.; German, David; Lindabury, David Peter; Luckado, Marshall Cleveland; Murphey, Craig; Rowell, John Bryan; Wilkinson, Brad

    1988-01-01

    SKITTER (Spacial Kinematic Inertial Translatory Tripod Extremity Robot) is a three-legged transport vehicle designed to perform under the unique environment of the moon. The objective of this project was to design a mechanical interface for SKITTER. This mechanical latching interface will allow SKITTER to use a series of implements such as drills, cranes, etc., and perform different tasks on the moon. The design emphasized versatility and detachability; that is, the interface design is the same for all implements, and connection and detachment is simple. After consideration of many alternatives, a system of three identical latches at each of the three interface points was chosen. The latching mechanism satisfies the design constraints because it facilitates connection and detachment. Also, the moving parts are protected from the dusty environment by housing plates.

  10. Brain-Computer Interface Workshop

    NASA Video Gallery

    At a g.tec-sponsored Brain-Computer Interface (BCI) workshop at the National Institute of Aerospace in Hampton, Va., volunteers were able to spell out words on a computer screen using using a g.tec...

  11. Antisite defects at oxide interfaces

    NASA Astrophysics Data System (ADS)

    Chen, Hanghui; Millis, Andrew

    We use ab initio calculations to estimate formation energies of cation (transition metal) antisite defects at oxide interfaces and to understand the basic physical effects that drive or suppress the formation of these defects. We find that antisite defects are favored in systems with substantial charge transfer across the interface, while Jahn-Teller distortions and itinerant ferromagnetism can prevent antisite defects and help stabilize atomically sharp interfaces. Our results enable identification of classes of systems that are more and less susceptible to the formation of antisite defects and motivate a range of experimental studies and further theoretical calculations to further explicate the oxide interface systems. This research was supported by National Science Foundation under Grant No. DMR-1120296 (H. Chen) and DOE-ER-046169 (A. J. Millis).

  12. Laser velocimeter (autocovariance) buffer interface

    NASA Technical Reports Server (NTRS)

    Clemmons, J. I., Jr.

    1981-01-01

    A laser velocimeter (autocovariance) buffer interface (LVABI) was developed to serve as the interface between three laser velocimeter high speed burst counters and a minicomputer. A functional description is presented of the instrument and its unique features which allow the studies of flow velocity vector analysis, turbulence power spectra, and conditional sampling of other phenomena. Typical applications of the laser velocimeter using the LVABI are presented to illustrate its various capabilities.

  13. The theory of interface slicing

    NASA Technical Reports Server (NTRS)

    Beck, Jon

    1993-01-01

    Interface slicing is a new tool which was developed to facilitate reuse-based software engineering, by addressing the following problems, needs, and issues: (1) size of systems incorporating reused modules; (2) knowledge requirements for program modification; (3) program understanding for reverse engineering; (4) module granularity and domain management; and (5) time and space complexity of conventional slicing. The definition of a form of static program analysis called interface slicing is addressed.

  14. Interfacing with an EVA Suit

    NASA Technical Reports Server (NTRS)

    Ross, Amy

    2011-01-01

    A NASA spacesuit under the EVA Technology Domain consists of a suit system; a PLSS; and a Power, Avionics, and Software (PAS) system. Ross described the basic functions, components, and interfaces of the PLSS, which consists of oxygen, ventilation, and thermal control subsystems; electronics; and interfaces. Design challenges were reviewed from a packaging perspective. Ross also discussed the development of the PLSS over the last two decades.

  15. Satellite services handbook. Interface guidelines

    NASA Astrophysics Data System (ADS)

    1983-12-01

    Satellite interfaces for on orbit servicing, both manned and unmanned are identified, and is intended to be used by designers of space vehicles, both foreign and domestic. A primary concern is for design of interfaces with the astronaut in the loop, especially extravehicular activity, but also intravehicular activity and operations that are remote but have man-in-the-loop. The main emphasis is on servicing in low earth orbits from the Space Shuttle and also from the Space Station or other platforms.

  16. Coal-shale interface detection

    NASA Technical Reports Server (NTRS)

    Broussard, P. H.; Burch, J. L.; Drost, E. J.; Stein, R. J. (Inventor)

    1979-01-01

    A penetrometer for coal-shale interface detection is presented. It is used with coal cutting equipment consisting of a reciprocating hammer, having an accelerometer mounted thereon to measure the impact of the hammer as it penetrates the ceiling or floor surface of a mine. Additionally, a pair of reflectometers simultaneously view the same surface, and the outputs from the accelerometer and reflectometers are detected and jointly registered to determine when an interface between coal and shale is being cut through.

  17. Coal-shale interface detector

    NASA Technical Reports Server (NTRS)

    Reid, H., Jr. (Inventor)

    1980-01-01

    A coal-shale interface detector for use with coal cutting equipment is described. The detector consists of a reciprocating hammer with an accelerometer to measure the impact of the hammer as it penetrates the ceiling or floor surface of a mine. Additionally, a pair of reflectometers simultaneously view the same surface, and the outputs from the accelerometer and reflectometers are detected and jointly registered to determine when an interface between coal and shale is being cut through.

  18. Morphological Stability of Faceted Interfaces

    NASA Technical Reports Server (NTRS)

    Abbaschian, Reza; Golyshev, V. D.; Gonik, M.; Tsvetivsky, V.; deVahlDavis, G.; Leonardi, E.

    2001-01-01

    The major focus of this investigation is to study the fundamentals of layer spreading mechanisms during growth of doped Ge (a facet forming material), and to determine the conditions for morphological instability of vicinal solid-liquid interfaces. The investigation will also lead to the determination of the effect of dopants on the layer growth kinetics, step free energy, and dopant capture by the advancing ledges. The theoretical treatment of growth of faceted interfaces indicates that the kinetics of a step on a growing vicinal interface considerably depends on its angle of inclination, the melt concentration, and characteristics of flow currents in the melt. The morphological stability of the interface also depends on these parameters, as well as on the density and spreading velocity of the steps. However, the treatment of the instability of the interface by the layer growth mechanism is rather difficult because it requires exact knowledge of the thermal and solutal fields, hydrodynamics of the melt, and supercooling at the interface. The results of recent space experiments of the principal investigator involving directional solidification of faceted Bi-Sn alloys have shown that the morphological stability of various crystallographic orientations is significantly affected by the anistropy in interfacial properties of the faceted alloy in general, and the interface kinetics in particular. These findings have also raised many important and fundamental questions, particularly with respect to the behavior of interfacial steps, which need to be addressed via additional groundbased and microgravity experiments. For the present investigation we will use a novel crystal growth technique which provides axial heat flux close to the solid-liquid boundary. The Axial Heat Processing (AHP) technique allows for precise control and determination of the heat and mass transfer close to the crystallization front, and the establishment of a planar interface over the entire cross

  19. Hydrophobic effect at aqueous interfaces

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew

    2005-01-01

    Conceptual basis for hydrophobic effects in bulk water and at aqueous interfaces have similar conceptual basis but often manifests itself differently. Using a wide range of computer simulations as the basis, I will review different forms of hydrophobic effects at a variety of interfaces starting from simple liquid-vapor and water-oil interfaces and progressing to water-membrane interfaces. I will start with discussing how water is organized at different interfaces, stressing both similarities and differences. The main thread is that, as in the bulk liquid, hydrophobic effects have profound influence on conformational equilibria and organization of both small molecules and macromolecules, but the result of this influence is quite different. Specifically, it will be shown that many small, but not necessarily amphiphilic molecules tend to accumulate at the interface and, and this tendency will be explained. Furthermore, I will show that many short peptides that are disordered in water spontaneously fold into well-defined structures in the interfacial environment. Biological implications of this self-organizing effect will be discussed.

  20. Adaptive interface for spoken dialog

    NASA Astrophysics Data System (ADS)

    Dusan, Sorin; Flanagan, James

    2002-05-01

    Speech has become increasingly important in human-computer interaction. Spoken dialog interfaces rely on automatic speech recognition, speech synthesis, language understanding, and dialog management. A main issue in dialog systems is that they typically are limited to pre-programmed vocabularies and sets of sentences. The research reported here focuses on developing an adaptive spoken dialog interface capable of acquiring new linguistic units and their corresponding semantics during the human-computer interaction. The adaptive interface identifies unknown words and phrases in the users utterances and asks the user for the corresponding semantics. The user can provide the meaning or the semantic representation of the new linguistic units through multiple modalities, including speaking, typing, pointing, touching, or showing. The interface then stores the new linguistic units in a semantic grammar and creates new objects defining the corresponding semantic representation. This process takes place during natural interaction between user and computer and, thus, the interface does not have to be rewritten and compiled to incorporate the newly acquired language. Users can personalize the adaptive spoken interface for different domain applications, or according to their personal preferences. [Work supported by NSF.

  1. Spoken Dialogue Interfaces: Integrating Usability

    NASA Astrophysics Data System (ADS)

    Spiliotopoulos, Dimitris; Stavropoulou, Pepi; Kouroupetroglou, Georgios

    Usability is a fundamental requirement for natural language interfaces. Usability evaluation reflects the impact of the interface and the acceptance from the users. This work examines the potential of usability evaluation in terms of issues and methodologies for spoken dialogue interfaces along with the appropriate designer-needs analysis. It unfolds the perspective to the usability integration in the spoken language interface design lifecycle and provides a framework description for creating and testing usable content and applications for conversational interfaces. Main concerns include the problem identification of design issues for usability design and evaluation, the use of customer experience for the design of voice interfaces and dialogue, and the problems that arise from real-life deployment. Moreover it presents a real-life paradigm of a hands-on approach for applying usability methodologies in a spoken dialogue application environment to compare against a DTMF approach. Finally, the scope and interpretation of results from both the designer and the user standpoint of usability evaluation are discussed.

  2. Active matter clusters at interfaces.

    NASA Astrophysics Data System (ADS)

    Copenhagen, Katherine; Gopinathan, Ajay

    2016-03-01

    Collective and directed motility or swarming is an emergent phenomenon displayed by many self-organized assemblies of active biological matter such as clusters of embryonic cells during tissue development, cancerous cells during tumor formation and metastasis, colonies of bacteria in a biofilm, or even flocks of birds and schools of fish at the macro-scale. Such clusters typically encounter very heterogeneous environments. What happens when a cluster encounters an interface between two different environments has implications for its function and fate. Here we study this problem by using a mathematical model of a cluster that treats it as a single cohesive unit that moves in two dimensions by exerting a force/torque per unit area whose magnitude depends on the nature of the local environment. We find that low speed (overdamped) clusters encountering an interface with a moderate difference in properties can lead to refraction or even total internal reflection of the cluster. For large speeds (underdamped), where inertia dominates, the clusters show more complex behaviors crossing the interface multiple times and deviating from the predictable refraction and reflection for the low velocity clusters. We then present an extreme limit of the model in the absence of rotational damping where clusters can become stuck spiraling along the interface or move in large circular trajectories after leaving the interface. Our results show a wide range of behaviors that occur when collectively moving active biological matter moves across interfaces and these insights can be used to control motion by patterning environments.

  3. Intrinsic chirality and prochirality at Air/R-(+)- and S-(-)-limonene interfaces: spectral signatures with interference chiral sum-frequency generation vibrational spectroscopy.

    PubMed

    Fu, Li; Zhang, Yun; Wei, Zhe-Hao; Wang, Hong-Fei

    2014-09-01

    We report in this work detailed measurements of the chiral and achiral sum-frequency vibrational spectra in the C-H stretching vibration region (2800-3050 cm(-1)) of the air/liquid interfaces of R-(+)-limonene and S-(-)-limonene, using the recently developed high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS). The achiral SFG spectra of R-limonene and S-limonene, as well as the RS racemic mixture (50/50 equal amount mixture), show that the corresponding molecular groups of the R and S enantiomers are with the same interfacial orientations. The interference chiral SFG spectra of the limonene enantiomers exhibit a spectral signature from the chiral response of the Cα-H stretching mode, and a spectral signature from the prochiral response of the CH(2) asymmetric stretching mode, respectively. The chiral spectral feature of the Cα-H stretching mode changes sign from R-(+)-limonene to S-(-)-limonene surfaces, and disappears for the RS racemic mixture surface. While the prochiral spectral feature of the CH(2) asymmetric stretching mode is the same for R-(+)-limonene and S-(-)-limonene surfaces, and also surprisingly remains the same for the RS racemic mixture surface. Therefore, the structures of the R-(+)-limonene and the S-(-)-limonene at the liquid interfaces are nevertheless not mirror images to each other, even though the corresponding groups have the same tilt angle from the interfacial normal, i.e., the R-(+)-limonene and the S-(-)-limonene at the surface are diastereomeric instead of enantiomeric. These results provide detailed information in understanding the structure and chirality of molecular interfaces and demonstrate the sensitivity and potential of SFG-VS as a unique spectroscopic tool for chirality characterization and chiral recognition at the molecular interface.

  4. Palaeomagnetism and K-Ar and 40Ar/39Ar ages in the Ali Sabieh area (Republic of Djibouti and Ethiopia): constraints on the mechanism of Aden ridge propagation into southeastern Afar during the last 10 Myr

    NASA Astrophysics Data System (ADS)

    Audin, L.; Quidelleur, X.; Coulié, E.; Courtillot, V.; Gilder, S.; Manighetti, I.; Gillot, P.-Y.; Tapponnier, P.; Kidane, T.

    2004-07-01

    A new detailed palaeomagnetic study of Tertiary volcanics, including extensive K-Ar and 40Ar/39Ar dating, helps constrain the deformation mechanisms related to the opening processes of the Afar depression (Ethiopia and Djibouti). Much of the Afar depression is bounded by 30 Myr old flood basalts and floored by the ca 2 Myr old Stratoid basalts, and evidence for pre-2 Ma deformation processes is accessible only on its borders. K-Ar and 40Ar/39Ar dating of several mineral phases from rhyolitic samples from the Ali Sabieh block shows indistinguishable ages around 20 Myr. These ages can be linked to separation of this block in relation to continental breakup. Different amounts of rotation are found to the north and south of the Holhol fault zone, which cuts across the northern part of the Ali Sabieh block. The southern domain did not record any rotation for the last 8 Myr, whereas the northern domain experienced approximately 12 +/- 9° of clockwise rotation. We propose to link this rotation to the counter-clockwise rotation observed in the Danakil block since 7 Ma. This provides new constraints on the early phases of rifting and opening of the southern Afar depression in connection with the propagation of the Aden ridge. A kinematic model of propagation and transfer of extension within southern Afar is proposed, with particular emphasis on the previously poorly-known period from 10 to 4 Ma.

  5. PREFACE: Functionalized Liquid Liquid Interfaces

    NASA Astrophysics Data System (ADS)

    Girault, Hubert; Kornyshev, Alexei A.; Monroe, Charles W.; Urbakh, Michael

    2007-09-01

    Most natural processes take place at interfaces. For this reason, surface science has been a focal point of modern research. At solid-liquid interfaces one can induce various species to adsorb or react, and thus may study interactions between the substrate and adsorbates, kinetic processes, optical properties, etc. Liquid-liquid interfaces, formed by immiscible liquids such as water and oil, have a number of distinctive features. Both sides of the interface are amenable to detailed physical and chemical analysis. By chemical or electrochemical means, metal or semiconductor nanoparticles can be formed or localised at the interface. Surfactants can be used to tailor surface properties, and also to place organic molecular or supermolecular constructions at the boundary between the liquids. Electric fields can be used to drive ions from one fluid to another, or even change the shape of the interface itself. In many cases, both liquids are optically transparent, making functionalized liquid-liquid interfaces promising for various optical applications based on the transmission or reflection of light. An advantage common to most of these systems is self-assembly; because a liquid-liquid interface is not mechanically constrained like a solid-liquid interface, it can easily access its most stable state, even after it has been driven far from equilibrium. This special issue focuses on four modes of liquid-liquid interfacial functionalization: the controlled adsorption of molecules or nanoparticles, the formation of adlayers or films, electrowetting, and ion transfer or interface-localized reactions. Interfacial adsorption can be driven electrically, chemically, or mechanically. The liquid-liquid interface can be used to study how anisotropic particles orient at a surface under the influence of a field, how surfactants interact with other adsorbates, and how nanoparticles aggregate; the transparency of the interface also makes the chirality of organic adsorbates amenable to

  6. Fluxes across a thermohaline interface

    NASA Astrophysics Data System (ADS)

    Fleury, M.; Lueck, R. G.

    1991-07-01

    Measurements of velocity and temperature microstructure and hydrography were made with a towed vehicle moving in and around a single interface in a double-diffusive staircase. The interface was traversed 222 times in a saw-tooth pattern over a track 35 km long. The salinity and potential temperature and density in the mixed layers adjacent to the interface were spatially uniform except for one 8 km long anomaly. The rate of dissipation of kinetic energy was uniformly low in the interface and in the mixed layers, except for one section 600 m long where a Kelvin-Helmholtz instability generated turbulence. For the non-turbulent section of the interface, the mean rate of dissipation was 30.2 × 10 -10 W kg -1 in the mixed layers and 9.5 × 10 -10 W kg -1 in the interface. The non-dimensional dissipation rate, ɛ/vN 2, was almost always less than 16 in the interface and therfore, there was no turblent buoyancy flux according to ROHRet al. (1988, Journal of Fluid Mechanics, 195, 77-111). The average double-diffusive flux of buoyancy by heat was 3.6 × 10 -10 W kg -1. Under certain assumptions the ratio of the flux of buoyancy by heat and salt can be estimated to be 0.53 ± 0.10, in good agreement with laboratory and theoretical estimates for salt fingers. The average Cox number was about 8 in the interface, consistent with the theories of STERN (1975, Ocean circulation physics, Academic Press) and KUNZE (1987, Journal of Marine Research, 45 533-556), but displayed an inverse dependence on the vertical temperature gradient which was not predicted. As a result, the flux of buoyancy, as well as the individual contributions by heat and salt, were independent of the local mean vertical temperature gradient and the buoyancy frequency. The length of the turbulent section of the interface was only 1.7% of the total length observed. However, the turbulence was intense—the mean rate of dissipation was 2.5 × 10 -8 W kg -1—and may have sufficiently enhanced the flux of heat to

  7. XML Translator for Interface Descriptions

    NASA Technical Reports Server (NTRS)

    Boroson, Elizabeth R.

    2009-01-01

    A computer program defines an XML schema for specifying the interface to a generic FPGA from the perspective of software that will interact with the device. This XML interface description is then translated into header files for C, Verilog, and VHDL. User interface definition input is checked via both the provided XML schema and the translator module to ensure consistency and accuracy. Currently, programming used on both sides of an interface is inconsistent. This makes it hard to find and fix errors. By using a common schema, both sides are forced to use the same structure by using the same framework and toolset. This makes for easy identification of problems, which leads to the ability to formulate a solution. The toolset contains constants that allow a programmer to use each register, and to access each field in the register. Once programming is complete, the translator is run as part of the make process, which ensures that whenever an interface is changed, all of the code that uses the header files describing it is recompiled.

  8. Interface dynamics of competing tissues

    NASA Astrophysics Data System (ADS)

    Podewitz, Nils; Jülicher, Frank; Gompper, Gerhard; Elgeti, Jens

    2016-08-01

    Tissues can be characterized by their homeostatic stress, i.e. the value of stress for which cell division and cell death balance. When two different tissues grow in competition, a difference of their homeostatic stresses determines which tissue grows at the expense of the second. This then leads to the propagation of the interface separating the tissues. Here, we study structural and dynamical properties of this interface by combining continuum theory with mesoscopic simulations of a cell-based model. Using a simulation box that moves with the interface, we find that a stationary state exists in which the interface has a finite width and propagates with a constant velocity. The propagation velocity in the simulations depends linearly on the homeostatic stress difference, in excellent agreement with the analytical predictions. This agreement is also seen for the stress and velocity profiles. Finally, we analyzed the interface growth and roughness as a function of time and system size. We estimated growth and roughness exponents, which differ from those previously obtained for simple tissue growth.

  9. Active matter clusters at interfaces

    NASA Astrophysics Data System (ADS)

    Copenhagen, Katherine; Gopinathan, Ajay

    Collective and directed motility or swarming is an emergent phenomenon displayed by many self-organized assemblies of active biological matter such as clusters of embryonic cells during tissue development and flocks of birds. Such clusters typically encounter very heterogeneous environments. What happens when a cluster encounters an interface between two different environments has implications for its function and fate. Here we study this problem by using a mathematical model of a cluster that treats it as a single cohesive unit whose movement depends on the nature of the local environment. We find that low speed clusters which exert forces but no active torques, encountering an interface with a moderate difference in properties can lead to refraction or even total internal reflection of the cluster. For large speeds and clusters with active torques, they show more complex behaviors crossing the interface multiple times, becoming trapped at the interface and deviating from the predictable refraction and reflection of the low velocity clusters. Our results show a wide range of behaviors that occur when collectively moving active biological matter moves across interfaces and these insights can be used to control motion by patterning environments.

  10. DIRAC: Secure web user interface

    NASA Astrophysics Data System (ADS)

    Casajus Ramo, A.; Sapunov, M.

    2010-04-01

    Traditionally the interaction between users and the Grid is done with command line tools. However, these tools are difficult to use by non-expert users providing minimal help and generating outputs not always easy to understand especially in case of errors. Graphical User Interfaces are typically limited to providing access to the monitoring or accounting information and concentrate on some particular aspects failing to cover the full spectrum of grid control tasks. To make the Grid more user friendly more complete graphical interfaces are needed. Within the DIRAC project we have attempted to construct a Web based User Interface that provides means not only for monitoring the system behavior but also allows to steer the main user activities on the grid. Using DIRAC's web interface a user can easily track jobs and data. It provides access to job information and allows performing actions on jobs such as killing or deleting. Data managers can define and monitor file transfer activity as well as check requests set by jobs. Production managers can define and follow large data productions and react if necessary by stopping or starting them. The Web Portal is build following all the grid security standards and using modern Web 2.0 technologies which allow to achieve the user experience similar to the desktop applications. Details of the DIRAC Web Portal architecture and User Interface will be presented and discussed.

  11. EVA-glass interface bond stability

    NASA Technical Reports Server (NTRS)

    Koenig, J. L.

    1984-01-01

    The ethylene vinyl acetate/glass interface bond stability was investigated. Special methods to determine the structure of polymer/glass interface were developed. Structural changes related to hydrothermal degradation of polymer/glass interface are examined. Methods to inhibit the degradation reaction which occur at polymer/glass interface are developed.

  12. Design of Interfaces for Information Seeking.

    ERIC Educational Resources Information Center

    Marchionini, Gary; Komlodi, Anita

    1998-01-01

    Examines the current state of user interface design for information seeking. Topics include technology push and interdisciplinarity; research and development; literature trends; user-centered interface design; information seeking in electronic environments; online information retrieval system interfaces; online public access catalog interfaces;…

  13. Interface Provides Standard-Bus Communication

    NASA Technical Reports Server (NTRS)

    Culliton, William G.

    1995-01-01

    Microprocessor-controlled interface (IEEE-488/LVABI) incorporates service-request and direct-memory-access features. Is circuit card enabling digital communication between system called "laser auto-covariance buffer interface" (LVABI) and compatible personal computer via general-purpose interface bus (GPIB) conforming to Institute for Electrical and Electronics Engineers (IEEE) Standard 488. Interface serves as second interface enabling first interface to exploit advantages of GPIB, via utility software written specifically for GPIB. Advantages include compatibility with multitasking and support of communication among multiple computers. Basic concept also applied in designing interfaces for circuits other than LVABI for unidirectional or bidirectional handling of parallel data up to 16 bits wide.

  14. Multi-robot control interface

    DOEpatents

    Bruemmer, David J [Idaho Falls, ID; Walton, Miles C [Idaho Falls, ID

    2011-12-06

    Methods and systems for controlling a plurality of robots through a single user interface include at least one robot display window for each of the plurality of robots with the at least one robot display window illustrating one or more conditions of a respective one of the plurality of robots. The user interface further includes at least one robot control window for each of the plurality of robots with the at least one robot control window configured to receive one or more commands for sending to the respective one of the plurality of robots. The user interface further includes a multi-robot common window comprised of information received from each of the plurality of robots.

  15. Nanofluidic interfaces in microfluidic networks

    SciTech Connect

    Millet, Larry J.; Doktycz, Mitchel John; Retterer, Scott T.

    2015-09-24

    The integration of nano- and microfluidic technologies enables the construction of tunable interfaces to physical and biological systems across relevant length scales. The ability to perform chemical manipulations of miniscule sample volumes is greatly enhanced through these technologies and extends the ability to manipulate and sample the local fluidic environments at subcellular, cellular and community or tissue scales. Here we describe the development of a flexible surface micromachining process for the creation of nanofluidic channel arrays integrated within SU-8 microfluidic networks. The use of a semi-porous, silicon rich, silicon nitride structural layer allows rapid release of the sacrificial silicon dioxide during the nanochannel fabrication. Nanochannel openings that form the interface to biological samples are customized using focused ion beam milling. The compatibility of these interfaces with on-chip microbial culture is demonstrated.

  16. PinBus Interface Design

    SciTech Connect

    Hammerstrom, Donald J.; Adgerson, Jewel D.; Sastry, Chellury; Pratt, Richard M.; Pratt, Robert G.

    2009-12-30

    On behalf of the U.S. Department of Energy, PNNL has explored and expanded upon a simple control interface that might have merit for the inexpensive communication of smart grid operational objectives (demand response, for example) to small electric end-use devices and appliances. The approach relies on bi-directional communication via the electrical voltage states of from one to eight shared interconnection pins. The name PinBus has been suggested and adopted for the proposed interface protocol. The protocol is defined through the presentation of state diagrams and the pins’ functional definitions. Both simulations and laboratory demonstrations are being conducted to demonstrate the elegance and power of the suggested approach. PinBus supports a very high degree of interoperability across its interfaces, allowing innumerable pairings of devices and communication protocols and supporting the practice of practically any smart grid use case.

  17. Nanofluidic interfaces in microfluidic networks

    DOE PAGES

    Millet, Larry J.; Doktycz, Mitchel John; Retterer, Scott T.

    2015-09-24

    The integration of nano- and microfluidic technologies enables the construction of tunable interfaces to physical and biological systems across relevant length scales. The ability to perform chemical manipulations of miniscule sample volumes is greatly enhanced through these technologies and extends the ability to manipulate and sample the local fluidic environments at subcellular, cellular and community or tissue scales. Here we describe the development of a flexible surface micromachining process for the creation of nanofluidic channel arrays integrated within SU-8 microfluidic networks. The use of a semi-porous, silicon rich, silicon nitride structural layer allows rapid release of the sacrificial silicon dioxidemore » during the nanochannel fabrication. Nanochannel openings that form the interface to biological samples are customized using focused ion beam milling. The compatibility of these interfaces with on-chip microbial culture is demonstrated.« less

  18. Intersurf: dynamic interface between proteins.

    PubMed

    Ray, Nicolas; Cavin, Xavier; Paul, Jean-Claude; Maigret, Bernard

    2005-01-01

    Protein docking is a fundamental biological process that links two proteins. This link is typically defined by an interaction between two large zones of the protein boundaries. Visualizing such an interface is useful to understand the process thanks to 3D protein structures, to estimate the quality of docking simulation results, and to classify interactions in order to predict docking affinity between classes of interacting zones. Since the interface may be defined by a surface that separates the two proteins, it is possible to create a map of interaction that allows comparisons to be performed in 2D. This paper presents a very fast algorithm that extracts an interface surface and creates a valid and low-distorted interaction map. Another benefit of our approach is that a pre-computed part of the algorithm enables the surface to be updated in real-time while residues are moved.

  19. Usable Interface Design for Everyone

    NASA Astrophysics Data System (ADS)

    de Castro Lozano, Carlos; Salcines, Enrique García; Sainz de Abajo, Beatriz; Burón Fernández, F. Javier; Ramírez, José Miguel; Recellado, José Gabriel Zato; Montoya, Rafael Sanchez; Bell, John; Marin, Francisco Alcantud

    When designing "interfaces for everyone" for interactive systems, it is important to consider factors such as cost, the intended market, the state of the environment, etc. User interfaces are fundamental for the developmental process in any application, and its design must be contemplated from the start. Of the distinct parts of a system (hardware and software), it is the interface that permits the user access to computer resources. The seven principles of "Universal Design" or "Design for Everyone" focus on a universal usable design, but at the same time acknowledge the influences of internal and external factors. Structural changes in social and health services could provide an increase in the well-being of a country's citizens through the use of self-care programming and proactive management/prevention of disease. Automated home platforms can act as an accessibility instrument which permits users to avoid, compensate, mitigate, or neutralize the deficiencies and dependencies caused by living alone.

  20. Multiferroic properties of the PbTiO3/La2/3Sr1/3MnO3 interface studied from first principles.

    PubMed

    Borisov, Vladislav; Ostanin, Sergey; Mertig, Ingrid

    2017-02-27

    Magnetoelectric coupling and spin polarization at the multiferroic PbTiO3/La2/3Sr1/3MnO3 (PTO/LSMO) interface is studied from first principles in view of the recent experimental observation of the tunneling magnetoresistance sign inversion in Co/PZT/LSMO tunnel junctions (D. Pantel et al.>, Nat. Mater. 11, 289 (2012)). Our results confirm the stabilization of the locally antiferromagnetic order in the manganite when the PTO polarization points away from the LSMO side, which changes the interface magnetization by 6.3-6.9 μB per surface unit cell in agreement with previous studies. We contribute by analyzing the charge transfer from the half-metallic LSMO side which induces metallicity and local magnetic moments in the interface PTO layers. This results in either p- or n-doped conductive behavior, depending on the polarization direction. Electronic correlations were determined to qualitatively change the picture for certain configurations, as far as the magnetic phase transition in the manganite and the spin character of the interface states are concerned. Most importantly, depending on the interface termination, the spin polarization of the PTO/LSMO interface is positive for one polarization state of PTO and acquires a "spin-valve" character upon the ferroelectric switching.

  1. DHMI: dynamic holographic microscopy interface

    NASA Astrophysics Data System (ADS)

    He, Xuefei; Zheng, Yujie; Lee, Woei Ming

    2016-12-01

    Digital holographic microscopy (DHM) is a powerful in-vitro biological imaging tool. In this paper, we report a fully automated off-axis digital holographic microscopy system completed with a graphical user interface in the Matlab environment. The interface primarily includes Fourier domain processing, phase reconstruction, aberration compensation and autofocusing. A variety of imaging operations such as region of interest selection, de-noising mode (filtering and averaging), low frame rate imaging for immediate reconstruction and high frame rate imaging routine ( 27 fps) are implemented to facilitate ease of use.

  2. Immersed interface methods. Final report

    SciTech Connect

    LeVeque, R.J.; Adams, L.M.; Bube, K.P.

    1996-11-01

    Cartesian grid methods encompass a wide variety of techniques used to solve partial differential equations in more than one space dimension on uniform Cartesian grids even when the underlying geometry is complex and not aligned with the grid. The authors` groups work on Immersed Interface Methods (IIM) was originally motivated by the desire to understand and improve the ``Immersed Boundary Method``, developed by Charles Peskin to solve incompressible Navier-Stokes equations in complicated geometries with moving elastic boundaries. This report briefly discusses the development of the Immersed Interface Methods and gives examples of application of the method in solving several partial differential equations.

  3. Segmental interpenetration at polymer interfaces

    SciTech Connect

    Russell, T.P.; Fleming, W.W.

    1989-01-01

    During the first year of this proposal significant strides have been made in understanding the nature of the interface in symmetric, diblock copolymers and the nature of the interface formed between immiscible homopolymers. Emphasis has been placed on the symmetric, diblock copolymers of polystyrene (PS) and polymethylmethacrylate (PMMA) since these diblock copolymers and the corresponding homopolymers are available over a wide range of molecular weight with narrow molecular weight distributions. In addition, the homopolymers and copolymers can be obtained with different levels of deuteration. Thus, these materials form a model system by which systematic studies on the interfacial behavior of homopolymers and block copolymers can be performed.

  4. User interfaces to expert systems

    SciTech Connect

    Agarwal, A.; Emrich, M.L.

    1988-10-01

    Expert Systems are becoming increasingly popular in environments where the user is not well versed in computers or the subject domain. They offer expert advice and can also explain their lines of reasoning. As these systems are applied to highly technical areas, they become complex and large. Therefore, User Systems Interfaces (USIs) become critical. This paper discusses recent technologies that can be applied to improved user communication. In particular, bar menus/graphics, mouse interfaces, touch screens, and voice links will be highlighted. Their applications in the context of SOFTMAN (The Software Manager Apprentice) a knowledge-based system are discussed. 18 refs., 2 figs.

  5. Chemical reactions at aqueous interfaces

    NASA Astrophysics Data System (ADS)

    Vecitis, Chad David

    2009-12-01

    Interfaces or phase boundaries are a unique chemical environment relative to individual gas, liquid, or solid phases. Interfacial reaction mechanisms and kinetics are often at variance with homogeneous chemistry due to mass transfer, molecular orientation, and catalytic effects. Aqueous interfaces are a common subject of environmental science and engineering research, and three environmentally relevant aqueous interfaces are investigated in this thesis: 1) fluorochemical sonochemistry (bubble-water), 2) aqueous aerosol ozonation (gas-water droplet), and 3) electrolytic hydrogen production and simultaneous organic oxidation (water-metal/semiconductor). Direct interfacial analysis under environmentally relevant conditions is difficult, since most surface-specific techniques require relatively `extreme' conditions. Thus, the experimental investigations here focus on the development of chemical reactors and analytical techniques for the completion of time/concentration-dependent measurements of reactants and their products. Kinetic modeling, estimations, and/or correlations were used to extract information on interfacially relevant processes. We found that interfacial chemistry was determined to be the rate-limiting step to a subsequent series of relatively fast homogeneous reactions, for example: 1) Pyrolytic cleavage of the ionic headgroup of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) adsorbed to cavitating bubble-water interfaces during sonolysis was the rate-determining step in transformation to their inorganic constituents carbon monoxide, carbon dioxide, and fluoride; 2) ozone oxidation of aqueous iodide to hypoiodous acid at the aerosol-gas interface is the rate-determining step in the oxidation of bromide and chloride to dihalogens; 3) Electrolytic oxidation of anodic titanol surface groups is rate-limiting for the overall oxidation of organics by the dichloride radical. We also found chemistry unique to the interface, for example: 1

  6. Fluorescent fluid interface position sensor

    DOEpatents

    Weiss, Jonathan D.

    2004-02-17

    A new fluid interface position sensor has been developed, which is capable of optically determining the location of an interface between an upper fluid and a lower fluid, the upper fluid having a larger refractive index than a lower fluid. The sensor functions by measurement, of fluorescence excited by an optical pump beam which is confined within a fluorescent waveguide where that waveguide is in optical contact with the lower fluid, but escapes from the fluorescent waveguide where that waveguide is in optical contact with the upper fluid.

  7. Interface standards for computer equipment

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The ability to configure data systems using modules provided by independent manufacturers is complicated by the wide range of electrical, mechanical, and functional characteristics exhibited within the equipment provided by different manufacturers of computers, peripherals, and terminal devices. A number of international organizations were and still are involved in the creation of standards that enable devices to be interconnected with minimal difficulty, usually involving only a cable or data bus connection that is defined by the standard. The elements covered by an interface standard are covered and the most prominent interface standards presently in use are identified and described.

  8. A database for TMT interface control documents

    NASA Astrophysics Data System (ADS)

    Gillies, Kim; Roberts, Scott; Brighton, Allan; Rogers, John

    2016-08-01

    The TMT Software System consists of software components that interact with one another through a software infrastructure called TMT Common Software (CSW). CSW consists of software services and library code that is used by developers to create the subsystems and components that participate in the software system. CSW also defines the types of components that can be constructed and their roles. The use of common component types and shared middleware services allows standardized software interfaces for the components. A software system called the TMT Interface Database System was constructed to support the documentation of the interfaces for components based on CSW. The programmer describes a subsystem and each of its components using JSON-style text files. A command interface file describes each command a component can receive and any commands a component sends. The event interface files describe status, alarms, and events a component publishes and status and events subscribed to by a component. A web application was created to provide a user interface for the required features. Files are ingested into the software system's database. The user interface allows browsing subsystem interfaces, publishing versions of subsystem interfaces, and constructing and publishing interface control documents that consist of the intersection of two subsystem interfaces. All published subsystem interfaces and interface control documents are versioned for configuration control and follow the standard TMT change control processes. Subsystem interfaces and interface control documents can be visualized in the browser or exported as PDF files.

  9. Enhanced Deposition by Electrostatic Field-Assistance Aggravating Diesel Exhaust Aerosol Toxicity for Human Lung Cells.

    PubMed

    Stoehr, Linda C; Madl, Pierre; Boyles, Matthew S P; Zauner, Roland; Wimmer, Monika; Wiegand, Harald; Andosch, Ancuela; Kasper, Gerhard; Pesch, Markus; Lütz-Meindl, Ursula; Himly, Martin; Duschl, Albert

    2015-07-21

    Air pollution is associated with increased risk of cardiovascular and pulmonary diseases, but conventional air quality monitoring gives no information about biological consequences. Exposing human lung cells at the air-liquid interface (ALI) to ambient aerosol could help identify acute biological responses. This study investigated electrode-assisted deposition of diesel exhaust aerosol (DEA) on human lung epithelial cells (A549) in a prototype exposure chamber. A549 cells were exposed to DEA at the ALI and under submerged conditions in different electrostatic fields (EFs) and were assessed for cell viability, membrane integrity, and IL-8 secretion. Qualitative differences of the DEA and its deposition under different EFs were characterized using scanning mobility particle sizer (SMPS) measurements, transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS). Upon exposure to DEA only, cell viability decreased and membrane impairment increased for cells at the ALI; submerged cells were unaffected. These responses were enhanced upon application of an EF, as was DEA deposition. No adverse effects were observed for filtered DEA or air only, confirming particle-induced responses. The prototype exposure chamber proved suitable for testing DEA-induced biological responses of cells at the ALI using electrode-assisted deposition and may be useful for analysis of other air pollutants.

  10. Establishment of a Novel Model for Anticancer Drug Resistance in Three-Dimensional Primary Culture of Tumor Microenvironment

    PubMed Central

    Sakurai, Masashi; Enjoji, Shuhei; Umata, Koji; Fujiwara, Nobuyuki; Tsuji, Shunya; Hazama, Shoichi

    2016-01-01

    Tumor microenvironment has been implicated in tumor development and progression. As a three-dimensional tumor microenvironment model, air liquid interface (ALI) organoid culture from oncogene transgenic mouse gastrointestinal tissues was recently produced. However, ALI organoid culture system from tissues of colorectal cancer patients has not been established. Here, we developed an ALI organoid model from normal and tumor colorectal tissues of human patients. Both organoids were successfully generated and showed cystic structures containing an epithelial layer and surrounding mesenchymal stromal cells. Structures of tumor organoids closely resembled primary tumor epithelium. Expression of an epithelial cell marker, E-cadherin, a goblet cell marker, MUC2, and a fibroblast marker, vimentin, but not a myofibroblast marker, α-smooth muscle actin (SMA), was observed in normal organoids. Expression of E-cadherin, MUC2, vimentin, and α-SMA was observed in tumor organoids. Expression of a cancer stem cell marker, LGR5 in tumor organoids, was higher than that in primary tumor tissues. Tumor organoids were more resistant to toxicity of 5-fluorouracil and Irinotecan than colorectal cancer cell lines, SW480, SW620, and HCT116. These findings indicate that ALI organoid culture from colorectal cancer patients may become a novel model that is useful for examining resistance to chemotherapy in tumor microenvironment. PMID:28119740

  11. Luminescent properties of SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} and its luminescence improvement by incorporating A{sup +} (A=Li, Na, and K)

    SciTech Connect

    Li, Panlai Wang, Zhijun Yang, Zhiping; Guo, Qinglin

    2014-12-15

    A novel green phosphor SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} is synthesized by a high temperature solid-state method, and its luminescent property is investigated. X-ray diffraction patterns of SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} indicate a similarity crystalline phase to SrZn{sub 2}(PO{sub 4}){sub 2}. SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} shows green emission under 369 nm excitation, and the prominent luminescence in green (544 nm) due to {sup 5}D{sub 4}–{sup 7}F{sub 5} transition of Tb{sup 3+}. For the 544 nm emission, excitation spectrum has several excitation band from 200 nm to 400 nm. Emission intensity of SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} is influenced by Tb{sup 3+} concentration, and concentration quenching effect of Tb{sup 3+} in SrZn{sub 2}(PO{sub 4}){sub 2} is also observed. With incorporating A{sup +} (A=Li, Na, and K) as compensator charge, the emission intensity of SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} can be obviously enhanced. CIE color coordinates of SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} locate in the green region. The results indicate this phosphor may be a potential application in white LEDs. - Graphical abstract: SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} can produce green emission under near-UV excitation, and its luminescent properties can be improved by incorporating A{sup +} (A=Li, Na, and K). - Highlights: • SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} can produce green emission under near-UV excitation. • Concentration quenching effect of Tb{sup 3+} in SrZn{sub 2}(PO{sub 4}){sub 2} is observed. • Emission intensities of SrZn{sub 2}(PO{sub 4}){sub 2}:Tb{sup 3+} are enhanced by codoped A{sup +} (A=Li, Na, K)

  12. The human/robot interface.

    PubMed

    Wiker, S F

    1993-10-01

    The use of telerobotic technology in space exploration is examined. Early aspirations for anthropomorphic designs and advances in the field are reviewed. The application of human factors engineering to robotics design and the human-machine interface are examined. New strategies in design and automation are presented.

  13. Interface Reconstruction with Directional Walking

    SciTech Connect

    Yao, J

    2009-05-22

    Young's interface reconstruction with three-dimensional arbitrary mesh, in general, is rather tedious to implement compared to the case of a regular mesh. The main difficulty comes from the construction of a planar facet that bounds a certain volume inside a cell. Unlike the five basic configurations with a Cartesian mesh, there can be a great number of different configurations in the case of a general mesh. We represent a simple method that can derive the topology/geometry of the intersection of arbitrary planar objects in a uniform way. The method is based on a directional walking on the surface of objects, and links the intersection points with the paths of the walking naturally defining the intersection of objects. The method works in both two and three dimensions. The method does not take advantage of convexity, thus decomposition of an object is not necessary. Therefore, the solution with this method will have a reduced number of edges and less data storage, compared with methods that use shape decomposition. The treatment is general for arbitrary polyhedrons, and no look-up tables are needed. The same operation can easily be extended for curved geometry. The implementation of this new algorithm shall allow the interface reconstruction on an arbitrary mesh to be as simple as it is on a regular mesh. Furthermore, we exactly compute the integral of partial cell volume bounded by quadratic interface. Therefore, interface reconstruction with higher than second order accuracy can be achieved on an arbitrary mesh.

  14. Coal-rock interface detector

    NASA Technical Reports Server (NTRS)

    Rose, S. D.; Crouch, C. E.; Jones, E. W. (Inventor)

    1979-01-01

    A coal-rock interface detector is presented which employs a radioactive source and radiation sensor. The source and sensor are separately and independently suspended and positioned against a mine surface of hydraulic pistons, which are biased from an air cushioned source of pressurized hydraulic fluid.

  15. Intelligent interfaces for expert systems

    NASA Technical Reports Server (NTRS)

    Villarreal, James A.; Wang, Lui

    1988-01-01

    Vital to the success of an expert system is an interface to the user which performs intelligently. A generic intelligent interface is being developed for expert systems. This intelligent interface was developed around the in-house developed Expert System for the Flight Analysis System (ESFAS). The Flight Analysis System (FAS) is comprised of 84 configuration controlled FORTRAN subroutines that are used in the preflight analysis of the space shuttle. In order to use FAS proficiently, a person must be knowledgeable in the areas of flight mechanics, the procedures involved in deploying a certain payload, and an overall understanding of the FAS. ESFAS, still in its developmental stage, is taking into account much of this knowledge. The generic intelligent interface involves the integration of a speech recognizer and synthesizer, a preparser, and a natural language parser to ESFAS. The speech recognizer being used is capable of recognizing 1000 words of connected speech. The natural language parser is a commercial software package which uses caseframe instantiation in processing the streams of words from the speech recognizer or the keyboard. The systems configuration is described along with capabilities and drawbacks.

  16. Spray algorithm without interface construction

    NASA Astrophysics Data System (ADS)

    Al-Kadhem Majhool, Ahmed Abed; Watkins, A. P.

    2012-05-01

    This research is aimed to create a new and robust family of convective schemes to capture the interface between the dispersed and the carrier phases in a spray without the need to build up the interface boundary. The selection of the Weighted Average Flux (WAF) scheme is due to this scheme being designed to deal with random flux scheme which is second-order accurate in space and time. The convective flux in each cell face utilizes the WAF scheme blended with Switching Technique for Advection and Capturing of Surfaces (STACS) scheme for high resolution flux limiters. In the next step, the high resolution scheme is blended with the WAF scheme to provide the sharpness and boundedness of the interface by using switching strategy. In this work, the Eulerian-Eulerian framework of non-reactive turbulent spray is set in terms of theoretical proposed methodology namely spray moments of drop size distribution, presented by Beck and Watkins [1]. The computational spray model avoids the need to segregate the local droplet number distribution into parcels of identical droplets. The proposed scheme is tested on capturing the spray edges in modelling hollow cone sprays without need to reconstruct two-phase interface. A test is made on simple comparison between TVD scheme and WAF scheme using the same flux limiter on convective flow hollow cone spray. Results show the WAF scheme gives a better prediction than TVD scheme. The only way to check the accuracy of the presented models is by evaluating the spray sheet thickness.

  17. Electronic Properties of Semiconductor Interfaces.

    DTIC Science & Technology

    1983-02-01

    AD-A130 745 ELECTRONIC PROPERTIES OF SEMICONDUCTOR INTERFACES(U) /; UNIVERSIDAD AUfONOMA DE MADRID (SPAIN) DEPT DE FISICA DEL ESTADO SOLIDO F FLORES...J.Sfinchez-Dehesa 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT. TASK AREA & WORK UNIT NUMBERS Departamento de Fisica del Estado Solido 6.11.02A

  18. The Human Interface Technology Laboratory.

    ERIC Educational Resources Information Center

    Washington Univ., Seattle. Washington Technology Center.

    This booklet contains information about the Human Interface Technology Laboratory (HITL), which was established by the Washington Technology Center at the University of Washington to transform virtual world concepts and research into practical, economically viable technology products. The booklet is divided into seven sections: (1) a brief…

  19. Willow: a uniform search interface.

    PubMed Central

    Ketchell, D S; Freedman, M M; Jordan, W E; Lightfoot, E M; Heyano, S; Libbey, P A

    1996-01-01

    The objective of the Willow Project is to develop a uniform search interface that allows a diverse community of users to retrieve information from heterogeneous network-based information resources. Willow separates the user interface from the database management or information retrieval system. It provides a graphic user interface to a variety of information resources residing on diverse hosts, and using different search engines and idiomatic query languages through networked-based client-server and Transmission Control Protocol/Internet Protocol (TCP/IP) protocols. It is based on a "database driver'' model, which allows new database hosts to be added without altering Willow itself. Willow employs a multimedia extension mechanism to launch external viewers to handle data in almost any form. Drivers are currently available for a local BRS/SEARCH system and the Z39.50 protocol. Students, faculty, clinicians, and researchers at the University of Washington are currently offered 30 local and remote databases via Willow. They conduct more than 250,000 sessions a month in libraries, medical centers and clinics, laboratories, and offices, and from home. The Massachusetts Institute of Technology is implementing Willow as its uniform search interface to Z39.50 hosts. PMID:8750388

  20. Gluing Soft Interfaces by Nanoparticles

    NASA Astrophysics Data System (ADS)

    Cao, Zhen; Dobrynin, Andrey

    Using a combination of the molecular dynamics simulations and scaling analysis we studied reinforcement of interface between two soft gel-like materials by spherical nanoparticles. Analysis of the simulations shows that the depth of penetration of a nanoparticle into a gel is determined by a balance of the elastic energy of the gel and nanoparticle deformations and the surface energy of nanoparticle/gel interface. In order to evaluate work of adhesion of the reinforced interface, the potential of mean force for separation of two gels was calculated. These simulations showed that the gel separation proceeds through formation of necks connecting nanoparticle with two gels. The shapes of the necks are controlled by a fine interplay between nanoparticle/gel surface energies and elastic energy of the neck deformation. Our simulations showed that by introducing nanoparticles at soft interfaces, the work required for separation of two gels could be 10-100 times larger than the work of adhesion between two gels without nanoparticle reinforcement. These results provide insight in understanding the mechanism of gluing soft gels and biological tissues by nano- and micro-sized particles. NSF DMR-1409710.

  1. Human-computer interface design

    SciTech Connect

    Bowser, S.E.

    1995-04-01

    Modern military forces assume that computer-based information is reliable, timely, available, usable, and shared. The importance of computer-based information is based on the assumption that {open_quotes}shared situation awareness, coupled with the ability to conduct continuous operations, will allow information age armies to observe, decide, and act faster, more correctly and more precisely than their enemies.{close_quotes} (Sullivan and Dubik 1994). Human-Computer Interface (HCI) design standardization is critical to the realization of the previously stated assumptions. Given that a key factor of a high-performance, high-reliability system is an easy-to-use, effective design of the interface between the hardware, software, and the user, it follows logically that the interface between the computer and the military user is critical to the success of the information-age military. The proliferation of computer technology has resulted in the development of an extensive variety of computer-based systems and the implementation of varying HCI styles on these systems. To accommodate the continued growth in computer-based systems, minimize HCI diversity, and improve system performance and reliability, the U.S. Department of Defense (DoD) is continuing to adopt interface standards for developing computer-based systems.

  2. Miniaturized neural interfaces and implants

    NASA Astrophysics Data System (ADS)

    Stieglitz, Thomas; Boretius, Tim; Ordonez, Juan; Hassler, Christina; Henle, Christian; Meier, Wolfgang; Plachta, Dennis T. T.; Schuettler, Martin

    2012-03-01

    Neural prostheses are technical systems that interface nerves to treat the symptoms of neurological diseases and to restore sensory of motor functions of the body. Success stories have been written with the cochlear implant to restore hearing, with spinal cord stimulators to treat chronic pain as well as urge incontinence, and with deep brain stimulators in patients suffering from Parkinson's disease. Highly complex neural implants for novel medical applications can be miniaturized either by means of precision mechanics technologies using known and established materials for electrodes, cables, and hermetic packages or by applying microsystems technologies. Examples for both approaches will be introduced and discussed. Electrode arrays for recording of electrocorticograms during presurgical epilepsy diagnosis have been manufactured using approved materials and a marking laser to achieve an integration density that is adequate in the context of brain machine interfaces, e.g. on the motor cortex. Microtechnologies have to be used for further miniaturization to develop polymer-based flexible and light weighted electrode arrays to interface the peripheral and central nervous system. Polyimide as substrate and insulation material will be discussed as well as several application examples for nerve interfaces like cuffs, filament like electrodes and large arrays for subdural implantation.

  3. Graphical fiber shaping control interface

    NASA Astrophysics Data System (ADS)

    Basso, Eric T.; Ninomiya, Yasuyuki

    2016-03-01

    In this paper, we present an improved graphical user interface for defining single-pass novel shaping techniques on glass processing machines that allows for streamlined process development. This approach offers unique modularity and debugging capability to researchers during the process development phase not usually afforded with similar scripting languages.

  4. BASIN: Beowulf Analysis Symbolic INterface

    NASA Astrophysics Data System (ADS)

    Vesperini, Enrico; Goldberg, David M.; McMillan, Stephen L. W.; Dura, James; Jones, Douglas

    2013-08-01

    BASIN (Beowulf Analysis Symbolic INterface) is a flexible, integrated suite of tools for multiuser parallel data analysis and visualization that allows researchers to harness the power of Beowulf PC clusters and multi-processor machines without necessarily being experts in parallel programming. It also includes general tools for data distribution and parallel operations on distributed data for developing libraries for specific tasks.

  5. Geometric similarity between protein-RNA interfaces.

    PubMed

    Zhou, Peng; Zou, Jianwei; Tian, Feifei; Shang, Zhicai

    2009-12-01

    A new method is described to measure the geometric similarity between protein-RNA interfaces quantitatively. The method is based on a procedure that dissects the interface geometry in terms of the spatial relationships between individual amino acid nucleotide pairs. Using this technique, we performed an all-on-all comparison of 586 protein-RNA interfaces deposited in the current Protein Data Bank, as the result, an interface-interface similarity score matrix was obtained. Based upon this matrix, hierarchical clustering was carried out which yielded a complete clustering tree for the 586 protein-RNA interfaces. By investigating the organizing behavior of the clustering tree and the SCOP classification of protein partners in complexes, a geometrically nonredundant, diverse data set (representative data set) consisting of 45 distinct protein-RNA interfaces was extracted for the purpose of studying protein-RNA interactions, RNA regulations, and drug design. We classified protein-RNA interfaces into three types. In type I, the families and interface structural classes of the protein partners, as well as the interface geometries are all similar. In type II, the interface geometries and the interface structural classes are similar, whereas the protein families are different. In type III, only the interface geometries are similar but the protein families and the interface structural classes are distinct. Furthermore, we also show two new RNA recognition themes derived from the representative data set.

  6. Ionic Structure at Dielectric Interfaces

    NASA Astrophysics Data System (ADS)

    Jing, Yufei

    The behavior of ions in liquids confined between macromolecules determines the outcome of many nanoscale assembly processes in synthetic and biological materials such as colloidal dispersions, emulsions, hydrogels, DNA, cell membranes, and proteins. Theoretically, the macromolecule-liquid boundary is often modeled as a dielectric interface and an important quantity of interest is the ionic structure in a liquid confined between two such interfaces. The knowledge gleaned from the study of ionic structure in such models can be useful in several industrial applications, such as biosensors, lithium-ion batteries double-layer supercapacitors for energy storage and seawater desalination. Electrostatics plays a critical role in the development of such functional materials. Many of the functions of these materials, result from charge and composition heterogeneities. There are great challenges in solving electrostatics problems in heterogeneous media with arbitrary shapes because electrostatic interactions remains unknown but depend on the particular density of charge distributions. Charged molecules in heterogeneous media affect the media's dielectric response and hence the interaction between the charges is unknown since it depends on the media and on the geometrical properties of the interfaces. To determine the properties of heterogeneous systems including crucial effects neglected in classical mean field models such as the hard core of the ions, the dielectric mismatch and interfaces with arbitrary shapes. The effect of hard core interactions accounts properly for short range interactions and the effect of local dielectric heterogeneities in the presence of ions and/or charged molecules for long-range interactions are both analyzed via an energy variational principle that enables to update charges and the medium's response in the same simulation time step. In particular, we compute the ionic structure in a model system of electrolyte confined by two planar dielectric

  7. Technique for converting non-conforming hexahedral-to-hexahedral interfaces into conforming interfaces

    DOEpatents

    Staten, Matthew L.; Shepherd, Jason F.; Ledoux, Frank; Shimada, Kenji; Merkley, Karl G.; Carbonera, Carlos

    2013-03-05

    A technique for conforming an interface between a first mesh and a second mesh is disclosed. A first interface surface in the first mesh and a second interface surface in the second mesh residing along the interface are identified. The first and second interface surfaces are initially non-conforming along the interface. Chords within the first and second interface surfaces that fall within a threshold separation distance of each other are paired. Sheets having chords that reside within the first or second interface surfaces are recursively inserted into or extracted from one or both of the first and second meshes until all remaining chords within the first interface surface are paired with corresponding chords in the second interface surface and all remaining chords within the second interface surface are paired with corresponding chords in the first interface surface.

  8. MIB Galerkin method for elliptic interface problems

    PubMed Central

    Xia, Kelin; Zhan, Meng; Wei, Guo-Wei

    2014-01-01

    Summary Material interfaces are omnipresent in the real-world structures and devices. Mathematical modeling of material interfaces often leads to elliptic partial differential equations (PDEs) with discontinuous coefficients and singular sources, which are commonly called elliptic interface problems. The development of high-order numerical schemes for elliptic interface problems has become a well defined field in applied and computational mathematics and attracted much attention in the past decades. Despite of significant advances, challenges remain in the construction of high-order schemes for nonsmooth interfaces, i.e., interfaces with geometric singularities, such as tips, cusps and sharp edges. The challenge of geometric singularities is amplified when they are associated with low solution regularities, e.g., tip-geometry effects in many fields. The present work introduces a matched interface and boundary (MIB) Galerkin method for solving two-dimensional (2D) elliptic PDEs with complex interfaces, geometric singularities and low solution regularities. The Cartesian grid based triangular elements are employed to avoid the time consuming mesh generation procedure. Consequently, the interface cuts through elements. To ensure the continuity of classic basis functions across the interface, two sets of overlapping elements, called MIB elements, are defined near the interface. As a result, differentiation can be computed near the interface as if there is no interface. Interpolation functions are constructed on MIB element spaces to smoothly extend function values across the interface. A set of lowest order interface jump conditions is enforced on the interface, which in turn, determines the interpolation functions. The performance of the proposed MIB Galerkin finite element method is validated by numerical experiments with a wide range of interface geometries, geometric singularities, low regularity solutions and grid resolutions. Extensive numerical studies confirm

  9. MIB Galerkin method for elliptic interface problems.

    PubMed

    Xia, Kelin; Zhan, Meng; Wei, Guo-Wei

    2014-12-15

    Material interfaces are omnipresent in the real-world structures and devices. Mathematical modeling of material interfaces often leads to elliptic partial differential equations (PDEs) with discontinuous coefficients and singular sources, which are commonly called elliptic interface problems. The development of high-order numerical schemes for elliptic interface problems has become a well defined field in applied and computational mathematics and attracted much attention in the past decades. Despite of significant advances, challenges remain in the construction of high-order schemes for nonsmooth interfaces, i.e., interfaces with geometric singularities, such as tips, cusps and sharp edges. The challenge of geometric singularities is amplified when they are associated with low solution regularities, e.g., tip-geometry effects in many fields. The present work introduces a matched interface and boundary (MIB) Galerkin method for solving two-dimensional (2D) elliptic PDEs with complex interfaces, geometric singularities and low solution regularities. The Cartesian grid based triangular elements are employed to avoid the time consuming mesh generation procedure. Consequently, the interface cuts through elements. To ensure the continuity of classic basis functions across the interface, two sets of overlapping elements, called MIB elements, are defined near the interface. As a result, differentiation can be computed near the interface as if there is no interface. Interpolation functions are constructed on MIB element spaces to smoothly extend function values across the interface. A set of lowest order interface jump conditions is enforced on the interface, which in turn, determines the interpolation functions. The performance of the proposed MIB Galerkin finite element method is validated by numerical experiments with a wide range of interface geometries, geometric singularities, low regularity solutions and grid resolutions. Extensive numerical studies confirm the

  10. Native-oxide-masked Si impurity-induced layer disordering of AlxGa1 - xAs-AlyGa1 - yAs-AlzGa1 - zAs quantum-well heterostructures

    NASA Astrophysics Data System (ADS)

    El-Zein, N.; Holonyak, N., Jr.; Kish, F. A.; Sugg, A. R.; Richard, T. A.; Dallesasse, J. M.; Smith, S. C.; Burnham, R. D.

    1991-08-01

    Data are presented showing that the native oxide that can be formed on high Al composition AlxGa1-xAs (x≳0.7) confining layers commonly employed on AlxGa1-xAs-AlyGa1-yAs-AlzGa1-zAs (y≳z) superlattices or quantum-well heterostructures serves as an effective mask against Si diffusion, and thus impurity-induced layer disordering. The high-quality native oxide is produced by the conversion of high-composition AlxGa1-xAs (x≳0.7) confining layers via H2O vapor oxidation (≳400 °C) in N2 carrier gas.

  11. Retraction: "Inactivation of Ink4a/Arf Leads to Deregulated Expression of miRNAs in K-Ras Transgenic Mouse Model of Pancreatic Cancer" by Ali et al.

    PubMed

    2016-10-01

    The above article, published online on June 21, 2012 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figure 5A to be inappropriately manipulated. Literature Cited Ali S, Banerjee S, Logna F, Bao B, Philip PA, Korc M, Sarkar FH. 2012. Inactivation of Ink4a/Arf leads to deregulated expression of miRNAs in K-Ras transgenic mouse model of pancreatic cancer. J Cell Physiol 227:3373-3380; doi: 10.1002/jcp.24036.

  12. Retraction: "Concurrent inhibition of NF-κB, cyclooxygenase-2, and epidermal growth factor receptor leads to greater anti-tumor activity in pancreatic cancer" by Ali et al.

    PubMed

    2016-08-01

    The above article, published online on March 8, 2010 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the first author and the corresponding author that found Figures 2A, 4, 6A, and 6C to be inappropriately manipulated. REFERENCE Ali S, Banerjee S, Schaffert JM, El-Rayes BF, Philip PA, Sarkar FH. 2010. Concurrent inhibition of NF-κB, cyclooxygenase-2, and epidermal growth factor receptor leads to greater anti-tumor activity in pancreatic cancer. J Cell Biochem 110:171-181; doi: 10.1002/jcb.22523.

  13. Characterization and Electrochemical Performance of SubstitutedLiNi0.4Co0.2-yAlyMn0.4O2 (0<_y<_0.2) Cathode Materials

    SciTech Connect

    Wilcox, James D.; Doeff, Marca M.

    2007-11-28

    A complete series of LiNi0.4Co0.2-yAlyMn0.4O2 (0<_y<_0.2) materials have been synthesized and investigated as cathode materials for lithium ion batteries. When cycled between 2.0 and 4.3 V vs. Li/Li+ at a current density of 0.1 mA/cm2, stable capacities of ~;;160 mAh/g for y=0 to ~;;110 mAh/g for y=0.2 are achieved. Upon increasing the current density, it is found that all materials containing aluminum show reduced polarization and improved rate performance. The optimal performance at all current densities was found for the compound with y=0.05. The effect of aluminumsubstitution on the crystal structure of the host is discussed.

  14. Application of multivariate statistical analysis and hydrochemical and isotopic investigations for evaluation of groundwater quality and its suitability for drinking and agriculture purposes: case of Oum Ali-Thelepte aquifer, central Tunisia.

    PubMed

    Hassen, Imen; Hamzaoui-Azaza, Fadoua; Bouhlila, Rachida

    2016-03-01

    Groundwater plays a dominant role in arid regions; it is among the most available water resources in Tunisia. Located in northwestern Tunisia, Oum Ali-Thelepte is a deep Miocene sedimentary aquifer, where groundwater is the most important source of water supply. The aim of the study is to investigate the hydrochemical processes leading to mineralization and to assess water quality with respect to agriculture and drinking for a better management of groundwater resources. To achieve such objectives, water analysis was carried out on 16 groundwater samples collected during January-February 2014. Stable isotopes and 26 hydrochemical parameters were examined. The interpretation of these analytical data showed that the concentrations of major and trace elements were within the permissible level for human use. The distribution of mineral processes in this aquifer was identified using conventional classification techniques, suggesting that the water facies gradually changes from Ca-HCO3 to Mg-SO4 type and are controlled by water-rock interaction. These results were endorsed using multivariate statistical methods such as principal component analysis and cluster analysis. The sustainability of groundwater for drinking and irrigation was assessed based on the water quality index (WQI) and on Wilcox and Richards's diagrams. This aquifer has been classified as "excellent water" serving good irrigation in the area. As for the stable isotope, the measurements showed that groundwater samples lay between global meteoric water line (GMWL) and LMWL; hence, this arrangement signifies that the recharge of the Oum Ali-Thelepte aquifer is ensured by rainwater infiltration through mountains in the border of the aquifer without evaporation effects.

  15. The Integrated Mode Management Interface

    NASA Technical Reports Server (NTRS)

    Hutchins, Edwin

    1996-01-01

    Mode management is the processes of understanding the character and consequences of autoflight modes, planning and selecting the engagement, disengagement and transitions between modes, and anticipating automatic mode transitions made by the autoflight system itself. The state of the art is represented by the latest designs produced by each of the major airframe manufacturers, the Boeing 747-400, the Boeing 777, the McDonnell Douglas MD-11, and the Airbus A320/A340 family of airplanes. In these airplanes autoflight modes are selected by manipulating switches on the control panel. The state of the autoflight system is displayed on the flight mode annunciators. The integrated mode management interface (IMMI) is a graphical interface to autoflight mode management systems for aircraft equipped with flight management computer systems (FMCS). The interface consists of a vertical mode manager and a lateral mode manager. Autoflight modes are depicted by icons on a graphical display. Mode selection is accomplished by touching (or mousing) the appropriate icon. The IMMI provides flight crews with an integrated interface to autoflight systems for aircraft equipped with flight management computer systems (FMCS). The current version is modeled on the Boeing glass-cockpit airplanes (747-400, 757/767). It runs on the SGI Indigo workstation. A working prototype of this graphics-based crew interface to the autoflight mode management tasks of glass cockpit airplanes has been installed in the Advanced Concepts Flight Simulator of the CSSRF of NASA Ames Research Center. This IMMI replaces the devices in FMCS equipped airplanes currently known as mode control panel (Boeing), flight guidance control panel (McDonnell Douglas), and flight control unit (Airbus). It also augments the functions of the flight mode annunciators. All glass cockpit airplanes are sufficiently similar that the IMMI could be tailored to the mode management system of any modern cockpit. The IMMI does not replace the

  16. Command Interface ASIC - Analog Interface ASIC Chip Set

    NASA Technical Reports Server (NTRS)

    Ruiz, Baldes; Jaffe, Burton; Burke, Gary; Lung, Gerald; Pixler, Gregory; Plummer, Joe; Katanyoutanant,, Sunant; Whitaker, William

    2003-01-01

    A command interface application-specific integrated circuit (ASIC) and an analog interface ASIC have been developed as a chip set for remote actuation and monitoring of a collection of switches, which can be used to control generic loads, pyrotechnic devices, and valves in a high-radiation environment. The command interface ASIC (CIA) can be used alone or in combination with the analog interface ASIC (AIA). Designed primarily for incorporation into spacecraft control systems, they are also suitable for use in high-radiation terrestrial environments (e.g., in nuclear power plants and facilities that process radioactive materials). The primary role of the CIA within a spacecraft or other power system is to provide a reconfigurable means of regulating the power bus, actuating all valves, firing all pyrotechnic devices, and controlling the switching of power to all switchable loads. The CIA is a mixed-signal (analog and digital) ASIC that includes an embedded microcontroller with supporting fault-tolerant switch control and monitoring circuitry that is capable of connecting to a redundant set of interintegrated circuit (I(sup 2)C) buses. Commands and telemetry requests are communicated to the CIA. Adherence to the I(sup 2)C bus standard helps to reduce development costs by facilitating the use of previously developed, commercially available components. The AIA is a mixed-signal ASIC that includes the analog circuitry needed to connect the CIA to a custom higher powered version of the I(sup 2)C bus. The higher-powered version is designed to enable operation with bus cables longer than those contemplated in the I(sup 2)C standard. If there are multiple higher-power I(sup 2)C-like buses, then there must an AIA between the CIA and each such bus. The AIA includes two identical interface blocks: one for the side-A I(sup 2)C clock and data buses and the other for the side B buses. All the AIAs on each side are powered from a common power converter module (PCM). Sides A and B

  17. Controlling the compositional inhomogeneities in AlxGa1-xN/AlyGa1-yN MQWs grown by PA-MBE: Effect on luminescence properties

    NASA Astrophysics Data System (ADS)

    Pramanik, Pallabi; Sen, Sayantani; Singha, Chirantan; Roy, Abhra Shankar; Das, Alakananda; Sen, Susanta; Bhattacharyya, Anirban; Kumar, Deepak; Sridhara Rao, D. V.

    2016-04-01

    Al0.35Ga0.65N/Al0.55Ga0.45N MQWs were grown by PA-MBE using a range of group III/V flux ratios. TEM images indicate sharp interfaces and well/barrier widths of 1.5/2 nm. We observe that small variations of group III/V flux ratio cause dramatic variations in the room temperature photoluminescence (PL) spectra. In addition to band edge luminescence, multiple low energy PL peaks are observed for growths under excess group III conditions, which are absent for near-stoichiometric growth. Temperature dependent PL measurements indicate that at room temperature, emission occurs due to transitions at potential fluctuations generated by the presence of compositional inhomogeneity. These effects are dominant for growth under excess group III conditions due to the presence of a metallic layer on the growth surface during deposition. This can be eliminated by the use of an Indium surfactant during growth, which modifies the diffusion length of Ga and Al adatoms. Under these conditions, the optical properties of MQWs are relatively insensitive to variations in group III to V flux ratio and hence substrate temperature, thus making them suitable for industrial-scale fabrication of optoelectronic devices in the ultraviolet range.

  18. Acoustic phonon modes in asymmetric AlxGa1-xN/GaN/AlyGa1-yN quantum wells

    NASA Astrophysics Data System (ADS)

    Zan, Y. H.; Ban, S. L.; Chai, Y. J.; Qu, Y.

    2017-02-01

    Using an elastic continuum model, the dispersion relations and phonon modes of propagating, confined, half space and interface acoustic phonons in asymmetric AlxGa1-xN/GaN/Al1-yGayN quantum wells (QWs) have been solved theoretically with the varieties of Al components x and y. Contrary to the previous conclusions, some regulations for the existence of the above different acoustic phonons are revealed as well as the transition conditions among these modes are also discussed. With increase of wave vectors, the dispersion relations split into several groups. Because the classification of these groups is related to the eigen frequencies of bulk materials forming QWs, phonon modes in these groups will be confined or propagating in different layers of QWs. Furthermore, the gradients of the dispersion relations' asymptotes are the velocities of longitudinal and the transverse acoustic phonons propagating in bulk materials in turns. The properties of the dispersion relations and their phonon modes are also analyzed in depth based on the cut-off conditions. By the changing of Al components x and y, the bottom of these groups will be modified to adjust eigen frequencies of AlxGa1-xN or Al1-yGayN layers. But the propagation properties of acoustic phonon modes will remain unchanged in each section.

  19. Ultrafast Thermal Transport at Interfaces

    SciTech Connect

    Cahill, David; Murphy, Catherine; Martin, Lane

    2014-10-21

    Our research program on Ultrafast Thermal Transport at Interfaces advanced understanding of the mesoscale science of heat conduction. At the length and time scales of atoms and atomic motions, energy is transported by interactions between single-particle and collective excitations. At macroscopic scales, entropy, temperature, and heat are the governing concepts. Key gaps in fundamental knowledge appear at the transitions between these two regimes. The transport of thermal energy at interfaces plays a pivotal role in these scientific issues. Measurements of heat transport with ultrafast time resolution are needed because picoseconds are the fundamental scales where the lack of equilibrium between various thermal excitations becomes a important factor in the transport physics. A critical aspect of our work has been the development of experimental methods and model systems that enabled more precise and sensitive investigations of nanoscale thermal transport.

  20. Practical Interfacing in the Laboratory

    NASA Astrophysics Data System (ADS)

    Derenzo, Stephen E.

    2003-05-01

    This text describes in practical terms how to use a desk-top computer to monitor and control laboratory experiments. The author clearly explains how to design electronic circuits and write computer programs to sense, analyse and display real-world quantities, including displacement, temperature, force, sound, light, and biomedical potentials. The book includes numerous laboratory exercises and appendices that provide practical information on microcomputer architecture and interfacing, including complete circuit diagrams and component lists. Topics include analog amplification and signal processing, digital-to-analog and analog-to-digital conversion, electronic sensors and actuators, digital and analog interfacing circuits, and programming. Only a very basic knowledge of electronics is assumed, making it ideal for college-level laboratory courses and for practising engineers and scientists. Everything you need to know about using a PC to monitor and control laboratory experiments Full of practical circuit designs and C-code examples Ideal for students and practising scientists

  1. Is structural interface standardization beneficial?

    NASA Technical Reports Server (NTRS)

    Dombert, W. E.

    1983-01-01

    Factors applicable to fixed angle, large field and fixed angle, large building flat plate photovoltaic (PV) generator arrays are discussed in the context of standardization. It is concluded that structural interface standardization may be highly desirable in any one major project, but not at this time in the overall PV industry. Attempts to mandate such standardization will act as a deterrent to long-range improvements. In specific projects, structural standardization should be defined at the largest practical interface, leaving the maximum possible freedom to the module and array manufacturer. There is a corollary area, however, where detailed standards would benefit the industry; the matter of Standard Practices. Work being done towards definition of acceptable/desirable practices in materials, finishes, fastening and locking methods, grounding techniques, lightning protection, etc., and in handling the environmental ranges, should be continued.

  2. Formal specification of human-computer interfaces

    NASA Technical Reports Server (NTRS)

    Auernheimer, Brent

    1990-01-01

    A high-level formal specification of a human computer interface is described. Previous work is reviewed and the ASLAN specification language is described. Top-level specifications written in ASLAN for a library and a multiwindow interface are discussed.

  3. Microprocessor-based interface for oceanography

    NASA Technical Reports Server (NTRS)

    Hansen, G. R.

    1979-01-01

    Ocean floor imaging system incorporates five identical microprocessor-based interface units each assigned to specific sonar instrument to simplify system. Central control module based on same microprocessor eliminates need for custom tailoring hardware interfaces for each instrument.

  4. Interfacing Simulations with Training Content

    DTIC Science & Technology

    2006-09-01

    learner tracking capabilities of a Learning Management System (LMS) has great potential to increase the efficacy of these technologies while reducing...standards to define the interface between a Learning Management System and learning content. Within the SCORM context, the term LMS implies a web...SCORM context, the Learning Management System (shown as the blue oval) is responsible for managing three forms of data (shown in medium blue

  5. Virtual Frame Buffer Interface Program

    NASA Technical Reports Server (NTRS)

    Wolfe, Thomas L.

    1990-01-01

    Virtual Frame Buffer Interface program makes all frame buffers appear as generic frame buffer with specified set of characteristics, allowing programmers to write codes that run unmodified on all supported hardware. Converts generic commands to actual device commands. Consists of definition of capabilities and FORTRAN subroutines called by application programs. Developed in FORTRAN 77 for DEC VAX 11/780 or DEC VAX 11/750 computer under VMS 4.X.

  6. Vibrational spectroscopy of water interfaces

    SciTech Connect

    Du, Quan

    1994-12-01

    The second order nonlinear optical processes of second harmonic generation and sum frequency generation are powerful and versatile tools for studying all kinds of surfaces. They possess unusual surface sensitivity due to the symmetry properties of the second order nonlinear susceptibility. The technique of infrared-visible sum frequency generation (SFG) is particularly attractive because it offers a viable way to do vibrational spectroscopy on any surfaces accessible to light with submonolayer sensitivity. In this thesis, the author applies SFG to study a number of important water interfaces. At the air/water interface, hydrophobic solid/water and liquid/water interfaces, it was found that approximately 25% of surface water molecules have one of their hydrogen pointing away from the liquid water. The large number of unsatisfied hydrogen bonds contributes significantly to the large interfacial energy of the hydrophobic surfaces. At the hydrophilic fused quartz/water interface and a fatty acid monolayer covered water surface, the structure and orientation of surface water molecules are controlled by the hydrogen bonding of water molecules with the surface OH groups and the electrostatic interaction with the surface field from the ionization of surface groups. A change of pH value in the bulk water can significantly change the relative importance of the two interactions and cause a drastic change in orientation of the surface water molecules. SFG has also been applied to study the tribological response of some model lubricant films. Monolayers of Langmuir-Blodgett films were found to disorder orientationaly under mildly high pressure and recover promptly upon removal of the applied pressure.

  7. Auditory interfaces: The human perceiver

    NASA Technical Reports Server (NTRS)

    Colburn, H. Steven

    1991-01-01

    A brief introduction to the basic auditory abilities of the human perceiver with particular attention toward issues that may be important for the design of auditory interfaces is presented. The importance of appropriate auditory inputs to observers with normal hearing is probably related to the role of hearing as an omnidirectional, early warning system and to its role as the primary vehicle for communication of strong personal feelings.

  8. Toward energy efficient neural interfaces.

    PubMed

    Peng, Chung-Ching; Xiao, Zhiming; Bashirullah, Rizwan

    2009-11-01

    This letter presents progress toward an energy efficient neural data acquisition transponder for brain-computer interfaces. The transponder utilizes a four-channel time-multiplexed analog front-end and an energy efficient short-range backscattering RF link to transmit digitized wireless data. In addition, a low-complexity autonomous and adaptive digital neural signal processor is proposed to minimize wireless bandwidth and overall power dissipation.

  9. Software handlers for process interfaces

    NASA Technical Reports Server (NTRS)

    Bercaw, R. W.

    1976-01-01

    Process interfaces are developed in an effort to reduce the time, effort, and money required to install computer systems. Probably the chief obstacle to the achievement of these goals lies in the problem of developing software handlers having the same degree of generality and modularity as the hardware. The problem of combining the advantages of modular instrumentation with those of modern multitask operating systems has not been completely solved, but there are a number of promising developments. The essential principles involved are considered.

  10. Multiple man-machine interfaces

    NASA Technical Reports Server (NTRS)

    Stanton, L.; Cook, C. W.

    1981-01-01

    The multiple man machine interfaces inherent in military pilot training, their social implications, and the issue of possible negative feedback were explored. Modern technology has produced machines which can see, hear, and touch with greater accuracy and precision than human beings. Consequently, the military pilot is more a systems manager, often doing battle against a target he never sees. It is concluded that unquantifiable human activity requires motivation that is not intrinsic in a machine.

  11. Tire/runway friction interface

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.

    1990-01-01

    An overview is given of NASA Langley's tire/runway pavement interface studies. The National Tire Modeling Program, evaluation of new tire and landing gear designs, tire wear and friction tests, and tire hydroplaning studies are examined. The Aircraft Landing Dynamics Facility is described along with some ground friction measuring vehicles. The major goals and scope of several joint FAA/NASA programs are identified together with current status and plans.

  12. The Interface Theory of Perception.

    PubMed

    Hoffman, Donald D; Singh, Manish; Prakash, Chetan

    2015-12-01

    Perception is a product of evolution. Our perceptual systems, like our limbs and livers, have been shaped by natural selection. The effects of selection on perception can be studied using evolutionary games and genetic algorithms. To this end, we define and classify perceptual strategies and allow them to compete in evolutionary games in a variety of worlds with a variety of fitness functions. We find that veridical perceptions--strategies tuned to the true structure of the world--are routinely dominated by nonveridical strategies tuned to fitness. Veridical perceptions escape extinction only if fitness varies monotonically with truth. Thus, a perceptual strategy favored by selection is best thought of not as a window on truth but as akin to a windows interface of a PC. Just as the color and shape of an icon for a text file do not entail that the text file itself has a color or shape, so also our perceptions of space-time and objects do not entail (by the Invention of Space-Time Theorem) that objective reality has the structure of space-time and objects. An interface serves to guide useful actions, not to resemble truth. Indeed, an interface hides the truth; for someone editing a paper or photo, seeing transistors and firmware is an irrelevant hindrance. For the perceptions of H. sapiens, space-time is the desktop and physical objects are the icons. Our perceptions of space-time and objects have been shaped by natural selection to hide the truth and guide adaptive behaviors. Perception is an adaptive interface.

  13. Implantable Neural Interfaces for Sharks

    DTIC Science & Technology

    2007-05-01

    neural codes from peripheral nerve using electrode arrays; Use simple chemical stimuli & multiple locations Completed Amino acid – evoked...rosette · Odorant perfusion across the olfactory rosette (amino acids : histidine, glutamate, cysteine) Implantable Neural Interfaces for Sharks...methane sulphonate ) at 100 mg/L on spontaneous activity recorded in the olfactory lobe. Rate histograms in 5 sec bins as a function of time. The

  14. Interface high-temperature superconductivity

    NASA Astrophysics Data System (ADS)

    Wang, Lili; Ma, Xucun; Xue, Qi-Kun

    2016-12-01

    Cuprate high-temperature superconductors consist of two quasi-two-dimensional (2D) substructures: CuO2 superconducting layers and charge reservoir layers. The superconductivity is realized by charge transfer from the charge reservoir layers into the superconducting layers without chemical dopants and defects being introduced into the latter, similar to modulation-doping in the semiconductor superlattices of AlGaAs/GaAs. Inspired by this scheme, we have been searching for high-temperature superconductivity in ultra-thin films of superconductors epitaxially grown on semiconductor/oxide substrates since 2008. We have observed interface-enhanced superconductivity in both conventional and unconventional superconducting films, including single atomic layer films of Pb and In on Si substrates and single unit cell (UC) films of FeSe on SrTiO3 (STO) substrates. The discovery of high-temperature superconductivity with a superconducting gap of ∼20 meV in 1UC-FeSe/STO has stimulated tremendous interest in the superconductivity community, for it opens a new avenue for both raising superconducting transition temperature and understanding the pairing mechanism of unconventional high-temperature superconductivity. Here, we review mainly the experimental progress on interface-enhanced superconductivity in the three systems mentioned above with emphasis on 1UC-FeSe/STO, studied by scanning tunneling microscopy/spectroscopy, angle-resolved photoemission spectroscopy and transport experiments. We discuss the roles of interfaces and a possible pairing mechanism inferred from these studies.

  15. Chiral magnetism at oxide interfaces

    NASA Astrophysics Data System (ADS)

    Randeria, Mohit

    2014-03-01

    There are tantalizing hints of magnetism at the n-type LaAlO3/SrTiO3 interface, but the experimental evidence remains controversial in view of some of the differences between different samples and probes. I will argue that if magnetism exists at interfaces, symmetry arguments imply chiral interactions that lead to a spiral ground state in zero external field and skyrmion crystals for H ≠ 0 . I will next present a microscopic model that provides a possible mechanism for the formation of local moments. I will show that the coupling of these moments to itinerant electrons leads to ferromagnetic double exchange together with Dzyaloshinskii-Moriya (DM) interactions and an easy-plane ``compass'' anisotropy, which arise from Rashba spin-orbit coupling (SOC) due to the lack of inversion symmetry at the interface. The compass term, often ignored in the literature on chiral magnetism, is shown to play a crucial role in determining the magnetic ground state. I will compare our results with existing torque magnetometry data on LAO/STO and try to reconcile it with scanning SQUID magnetometry. Finally, I will present the phase diagram in a field and show that easy-plane anisotropy stabilizes an unexpectedly large skyrmion crystal phase and describe its properties. (Work done in collaboration with Sumilan Banerjee, Onur Erten, Daniel Kestner and James Rowland). Supported by DOE-BES DE-SC0005035, NSF-DMR-1006532 and NSF MRSEC DMR-0820414.

  16. Programmable atom-photon quantum interface

    NASA Astrophysics Data System (ADS)

    Kurz, Christoph; Eich, Pascal; Schug, Michael; Müller, Philipp; Eschner, Jürgen

    2016-06-01

    We present the implementation of a programmable atom-photon quantum interface, employing a single trapped +40Ca ion and single photons. Depending on its mode of operation, the interface serves as a bidirectional atom-photon quantum-state converter, as a source of entangled atom-photon states, or as a quantum frequency converter of single photons. The interface lends itself particularly to interfacing ions with spontaneous parametric down-conversion-based single-photon or entangled-photon-pair sources.

  17. INL Multi-Robot Control Interface

    SciTech Connect

    2005-03-30

    The INL Multi-Robot Control Interface controls many robots through a single user interface. The interface includes a robot display window for each robot showing the robot’s condition. More than one window can be used depending on the number of robots. The user interface also includes a robot control window configured to receive commands for sending to the respective robot and a multi-robot common window showing information received from each robot.

  18. Towards automation of user interface design

    NASA Technical Reports Server (NTRS)

    Gastner, Rainer; Kraetzschmar, Gerhard K.; Lutz, Ernst

    1992-01-01

    This paper suggests an approach to automatic software design in the domain of graphical user interfaces. There are still some drawbacks in existing user interface management systems (UIMS's) which basically offer only quantitative layout specifications via direct manipulation. Our approach suggests a convenient way to get a default graphical user interface which may be customized and redesigned easily in further prototyping cycles.

  19. Film bonded fuel cell interface configuration

    DOEpatents

    Kaufman, Arthur; Terry, Peter L.

    1985-01-01

    An improved interface configuration for use between adjacent elements of a fuel cell stack. The interface is impervious to gas and liquid and provides resistance to corrosion by the electrolyte of the fuel cell. A multi-layer arrangement for the interface provides bridging electrical contact with a hot-pressed resin filling the void space.

  20. Molecular Dynamics Simulations of Interface Failure

    NASA Astrophysics Data System (ADS)

    Bachlechner, Martina E.; Cao, Deng; Leonard, Robert H.; Owens, Eli T.; Swan, Wm. Trevor, III; Ducatman, Samuel C.

    2007-03-01

    The mechanical integrity of silicon/silicon nitride interfaces is of great importance in their applications in micro electronics and solar cells. Large-scale molecular dynamics simulations are an excellent tool to study mechanical and structural failure of interfaces subjected to externally applied stresses and strains. When pulling the system parallel to the interface, cracks in silicon nitride and slip and pit formation in silicon are typical failure mechanisms. Hypervelocity impact perpendicular to the interface plane leads to structural transformation and delamination at the interface. Influence of system temperature, strain rate, impact velocity, and system size on type and characteristics of failure will be discussed.

  1. Intelligent subsystem interface for modular hardware system

    NASA Technical Reports Server (NTRS)

    Krening, Douglas N. (Inventor); Lannan, Gregory B. (Inventor); Schneiderwind, Michael J. (Inventor); Schneiderwind, Robert A. (Inventor); Caffrey, Robert T. (Inventor)

    2000-01-01

    A single chip application specific integrated circuit (ASIC) which provides a flexible, modular interface between a subsystem and a standard system bus. The ASIC includes a microcontroller/microprocessor, a serial interface for connection to the bus, and a variety of communications interface devices available for coupling to the subsystem. A three-bus architecture, utilizing arbitration, provides connectivity within the ASIC and between the ASIC and the subsystem. The communication interface devices include UART (serial), parallel, analog, and external device interface utilizing bus connections paired with device select signals. A low power (sleep) mode is provided as is a processor disable option.

  2. TAXI Interface Demultiplexes Proprietarily Formatted Data

    NASA Technical Reports Server (NTRS)

    Newnan, Bruce G.; Ahiport, Steven F.

    2001-01-01

    The 'TAXI Direct-to-Disk' interface is a special purpose interface unit for demultiplexing of data from a Racal Storeplex (or equivalent) multichannel recorder onto one or more hard disks that reside in, and/or are controlled by, a personal computer (PC). The acronym 'TAXI' signifies transparent asynchronous transceiver interface. The TAXI interface was developed for original use in capturing data from instrumentation on a test stand in a NASA rocket testing facility. The installation of the TAXI interface, in conjunction with other modifications, causes the transfer of data to take place in real time, so that the data are immediately available for review during or after the test.

  3. Transient aspects of stream interface signatures

    SciTech Connect

    Crooker, N.U.; Shodhan, S.; Forsyth, R.J.; Burton, M.E.; Gosling, J.T.; Fitzenreiter, R.J.; Lepping, R.P.

    1999-06-01

    Although stream interfaces are steady-state, corotating boundaries between slow and fast solar wind, their signatures are sometimes associated with transient features. Here the authors illustrate two modes of association: interfaces trailing interplanetary coronal mass ejections (ICMEs) at 1 AU and interfaces within ICMEs in the range 4--5 AU. The former are readily understood as boundaries between transient slow wind and steady-state fast wind, where the ICMEs add variability to the interface signatures. The latter are puzzling and may be related to evolution of interfaces.

  4. Model study of protein unfolding by interfaces

    NASA Astrophysics Data System (ADS)

    Chakarova, S. D.; Carlsson, A. E.

    2004-02-01

    We study interface-induced protein unfolding on hydrophobic and polar interfaces by means of a two-dimensional lattice model and an exhaustive enumeration ground-state structure search, for a set of model proteins of length 20 residues. We compare the effects of the two types of interfaces, and search for criteria that influence the retention of a protein’s native-state structure upon adsorption. We find that the unfolding proceeds by a large, sudden loss of native contacts. The unfolding at polar interfaces exhibits similar behavior to that at hydrophobic interfaces but with a much weaker interface coupling strength. Further, we find that the resistance of proteins to unfolding in our model is positively correlated with the magnitude of the folding energy in the native-state structure, the thermal stability (or energy gap) for that structure, and the interface energy for native-state adsorption. We find these factors to be of roughly equal importance.

  5. Experiments showing dynamics of materials interfaces

    SciTech Connect

    Benjamin, R.F.

    1997-02-01

    The discipline of materials science and engineering often involves understanding and controlling properties of interfaces. The authors address the challenge of educating students about properties of interfaces, particularly dynamic properties and effects of unstable interfaces. A series of simple, inexpensive, hands-on activities about fluid interfaces provides students with a testbed to develop intuition about interface dynamics. The experiments highlight the essential role of initial interfacial perturbations in determining the dynamic response of the interface. The experiments produce dramatic, unexpected effects when initial perturbations are controlled and inhibited. These activities help students to develop insight about unstable interfaces that can be applied to analogous problems in materials science and engineering. The lessons examine ``Rayleigh-Taylor instability,`` an interfacial instability that occurs when a higher-density fluid is above a lower-density fluid.

  6. The cartilage-bone interface.

    PubMed

    Hoemann, Caroline D; Lafantaisie-Favreau, Charles-Hubert; Lascau-Coman, Viorica; Chen, Gaoping; Guzmán-Morales, Jessica

    2012-05-01

    In the knee joint, the purpose of the cartilage-bone interface is to maintain structural integrity of the osteochondral unit during walking, kneeling, pivoting, and jumping--during which tensile, compressive, and shear forces are transmitted from the viscoelastic articular cartilage layer to the much stiffer mineralized end of the long bone. Mature articular cartilage is integrated with subchondral bone through a approximately 20 to approximately 250 microm thick layer of calcified cartilage. Inside the calcified cartilage layer, perpendicular chondrocyte-derived collagen type II fibers become structurally cemented to collagen type I osteoid deposited by osteoblasts. The mature mineralization front is delineated by a thin approximately 5 microm undulating tidemark structure that forms at the base of articular cartilage. Growth plate cartilage is anchored to epiphyseal bone, sometimes via a thin layer of calcified cartilage and tidemark, while the hypertrophic edge does not form a tidemark and undergoes continual vascular invasion and endochondral ossification (EO) until skeletal maturity upon which the growth plates are fully resorbed and replaced by bone. In this review, the formation of the cartilage-bone interface during skeletal development and cartilage repair, and its structure and composition are presented. Animal models and human anatomical studies show that the tidemark is a dynamic structure that forms within a purely collagen type II-positive and collagen type I-negative hyaline cartilage matrix. Cartilage repair strategies that elicit fibrocartilage, a mixture of collagen type I and type II, are predicted to show little tidemark/calcified cartilage regeneration and to develop a less stable repair tissue-bone interface. The tidemark can be regenerated through a bone marrow-driven growth process of EO near the articular surface.

  7. Surface rheology and interface stability.

    SciTech Connect

    Yaklin, Melissa A.; Cote, Raymond O.; Moffat, Harry K.; Grillet, Anne Mary; Walker, Lynn; Koehler, Timothy P.; Reichert, Matthew D.; Castaneda, Jaime N.; Mondy, Lisa Ann; Brooks, Carlton, F.

    2010-11-01

    We have developed a mature laboratory at Sandia to measure interfacial rheology, using a combination of home-built, commercially available, and customized commercial tools. An Interfacial Shear Rheometer (KSV ISR-400) was modified and the software improved to increase sensitivity and reliability. Another shear rheometer, a TA Instruments AR-G2, was equipped with a du Nouey ring, bicone geometry, and a double wall ring. These interfacial attachments were compared to each other and to the ISR. The best results with the AR-G2 were obtained with the du Nouey ring. A Micro-Interfacial Rheometer (MIR) was developed in house to obtain the much higher sensitivity given by a smaller probe. However, it was found to be difficult to apply this technique for highly elastic surfaces. Interfaces also exhibit dilatational rheology when the interface changes area, such as occurs when bubbles grow or shrink. To measure this rheological response we developed a Surface Dilatational Rheometer (SDR), in which changes in surface tension with surface area are measured during the oscillation of the volume of a pendant drop or bubble. All instruments were tested with various surfactant solutions to determine the limitations of each. In addition, foaming capability and foam stability were tested and compared with the rheology data. It was found that there was no clear correlation of surface rheology with foaming/defoaming with different types of surfactants, but, within a family of surfactants, rheology could predict the foam stability. Diffusion of surfactants to the interface and the behavior of polyelectrolytes were two subjects studied with the new equipment. Finally, surface rheological terms were added to a finite element Navier-Stokes solver and preliminary testing of the code completed. Recommendations for improved implementation were given. When completed we plan to use the computations to better interpret the experimental data and account for the effects of the underlying bulk

  8. Water Tank with Capillary Air/Liquid Separation

    NASA Technical Reports Server (NTRS)

    Ungar, Eugene K.; Smith, Frederick; Edeen, Gregg; Almlie, Jay C.

    2010-01-01

    A bladderless water tank (see figure) has been developed that contains capillary devices that allow it to be filled and emptied, as needed, in microgravity. When filled with water, the tank shields human occupants of a spacecraft against cosmic radiation. A membrane that is permeable by air but is hydrophobic (neither wettable nor permeable by liquid water) covers one inside surface of the tank. Grooves between the surface and the membrane allow air to flow through vent holes in the surface as the tank is filled or drained. A margin of wettable surface surrounds the edges of the membrane, and all the other inside tank surfaces are also wettable. A fill/drain port is located in one corner of the tank and is covered with a hydrophilic membrane. As filling begins, water runs from the hydrophilic membrane into the corner fillets of the tank walls. Continued filling in the absence of gravity will result in a single contiguous air bubble that will be vented through the hydrophobic membrane. The bubble will be reduced in size until it becomes spherical and smaller than the tank thickness. Draining the tank reverses the process. Air is introduced through the hydrophobic membrane, and liquid continuity is maintained with the fill/drain port through the corner fillets. Even after the tank is emptied, as long as the suction pressure on the hydrophilic membrane does not exceed its bubble point, no air will be drawn into the liquid line.

  9. Gloved Human-Machine Interface

    NASA Technical Reports Server (NTRS)

    Adams, Richard (Inventor); Olowin, Aaron (Inventor); Hannaford, Blake (Inventor)

    2015-01-01

    Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, composition of matter, and/or user interface adapted for and/or resulting from, and/or a method and/or machine-readable medium comprising machine-implementable instructions for, activities that can comprise and/or relate to: tracking movement of a gloved hand of a human; interpreting a gloved finger movement of the human; and/or in response to interpreting the gloved finger movement, providing feedback to the human.

  10. Pattern formation at liquid interfaces

    NASA Astrophysics Data System (ADS)

    Heidel, Barbara; Knobler, Charles M.

    1990-01-01

    Quantitative experimental investigations of pattern formation at a liquid interface are described. The reaction studied is the photoreduction of Fe 3+ in aqueous solution and the subsequent formation of Turnbull's Blue. Both the wavelength of the pattern and the time at which the break in homogeneity occurs have been studied as functions of the concentrations of the reactants and the viscosity of the solvent. Many of the features of the process are consistent with a mechanism in which autocatalysis is enhanced by double diffusion. Preliminary studies of pattern formation in the KI/starch/chloralhydrate system are also presented.

  11. Techniques for Interfacing Multiplex Systems.

    DTIC Science & Technology

    1981-02-01

    Study 6 1.2. 3 Selection of Techniques 7 1.3 RECOMMENDATIONS AND SUMMARY 7 1.3.1 ARINC and H009 (F-15) Interfaces 7 1. 3. 2 Basic Signal...Override Transmitter Shutdown 72 3.4.8 Selected Transmitter Shutdown 72 viii TABLE OF CONTENTS (cont t d) Page I 3.4.9 Override Selected Transmitter...Common Mode Rejection 90 4.0 SELECTION OF TECHNIQUES 91 4.1 BACKGROUND AND RATIONALE 91 4.1.1 Ease of Retrofit 91 4. 1. 2 Future Implementation 92 4

  12. Metawidgets in the multimodal interface

    SciTech Connect

    Blattner, M.M. Anderson Cancer Center, Houston, TX ); Glinert, E.P.; Jorge, J.A.; Ormsby, G.R. . Dept. of Computer Science)

    1991-01-01

    We analyze two intertwined and fundamental issues concerning computer-to-human communication in the multimodal interfaces: the interplay between sound and graphics, and the role of object persistence. Our observations lead us to introduce metawidgets as abstract entities capable of manifesting themselves to users as image, as sound, or as various combinations and/or sequences of the two media. We show examples of metawidgets in action, and discuss mechanisms for choosing among alternative media for metawidget instantiation. Finally, we describe a couple of experimental microworlds we have implemented to test out some of our ideas. 17 refs., 7 figs.

  13. Interface Circuit For Printer Port

    NASA Technical Reports Server (NTRS)

    Tucker, Jerry H.; Yadlowsky, Ann B.

    1991-01-01

    Electronic circuit, called printer-port interface circuit (PPI) developed to overcome certain disadvantages of previous methods for connecting IBM PC or PC-compatible computer to other equipment. Has both reading and writing modes of operation. Very simple, requiring only six integrated circuits. Provides for moderately fast rates of transfer of data and uses existing unmodified circuit card in IBM PC. When used with appropriate software, circuit converts printer port on IBM PC, XT, AT, or compatible personal computer to general purpose, 8-bit-data, 16-bit address bus that connects to multitude of devices.

  14. Gestural interfaces for immersive environments

    NASA Astrophysics Data System (ADS)

    Margolis, Todd

    2014-02-01

    We are witnessing an explosion of new forms of Human Computer Interaction devices lately for both laboratory research and home use. With these new affordance in user interfaces (UI), how can gestures be used to improve interaction for large scale immersive display environments. Through the investigation of full body, head and hand tracking, this paper will discuss various modalities of gesture recognition and compare their usability to other forms of interactivity. We will explore a specific implementation of hand gesture tracking within a large tiled display environment for use with common collaborative media interaction activities.

  15. Crossover behavior in interface depinning.

    PubMed

    Chen, Y J; Zapperi, Stefano; Sethna, James P

    2015-08-01

    We study the crossover scaling behavior of the height-height correlation function in interface depinning in random media. We analyze experimental data from a fracture experiment and simulate an elastic line model with nonlinear couplings and disorder. Both exhibit a crossover between two different universality classes. For the experiment, we fit a functional form to the universal crossover scaling function. For the model, we vary the system size and the strength of the nonlinear term and describe the crossover between the two universality classes with a multiparameter scaling function. Our method provides a general strategy to extract scaling properties in depinning systems exhibiting crossover phenomena.

  16. Le diagnostic anténatal de la trisomie 21 par l'hybridation in situ en fluorescence (FISH): à propos des premiers tests réalisés au Maroc

    PubMed Central

    Lamzouri, Afaf; Natiq, Abdelhafid; Tajir, Mariam; Sendid, Mohamed; Sefiani, Abdelaziz

    2012-01-01

    Introduction Le but de cette étude était de présenter les premiers résultats de diagnostic anténatal de la trisomie 21 par la technique d'hybridation in situ en fluorescence (FISH) au Maroc et discuter son intérêt dans le diagnostic rapide de cette aneuploïdie. Méthodes Ce travail a été réalisé chez 23 femmes avec des grossesses à haut risque de trisomie 21. La moyenne d’âge des gestantes étaient de 37,43 ans avec des extrêmes de 21 et 43 ans. Toutes étaient musulmanes mariées, mariage légitimé par la Charia, dont trois mariages consanguins, sauf une originaire de la République Démocratique du Congo qui était chrétienne et concubine. La majorité des femmes étaient fonctionnaires et avaient un niveau de scolarisation moyen à élevé. Toutes les patientes ont bénéficié d'une consultation de génétique médicale au cours de laquelle il leur a été donné des informations sur la technique, son intérêt et ses limites. Il s'agit de femmes enceintes qui avaient soit un âge maternel élevé ou des signes d'appel échographiques et/ ou biochimiques. Une des patientes était porteuse d'une translocation robertsonienne t(14;21) équilibrée. Une amniocentèse a été réalisée chez toutes les gestantes et aucun avortement n'a était induit par ce geste invasif. L’âge gestationnel moyen à la première consultation était de 14 semaines d'aménorrhée (SA) et à l'amniocentèse était de 16 SA et 5 jours. L'analyse FISH a été réalisée, après consentement des couples, sur des cellules non cultivées à partir des échantillons de liquides amniotiques, en utilisant des sondes spécifiques du chromosome 21. Résultats Parmi les 23 patientes qui ont bénéficiées d'un diagnostic anténatal de la trisomie 21 par la technique FISH, nous avons pu rassurer 21 d'entre elles, et nous avons détecté deux cas de trisomie 21 fœtal. Conclusion La technique FISH permet un diagnostic anténatal rapide, en moins de 48h, de la trisomie 21 sur

  17. Brain Computer Interfaces, a Review

    PubMed Central

    Nicolas-Alonso, Luis Fernando; Gomez-Gil, Jaime

    2012-01-01

    A brain-computer interface (BCI) is a hardware and software communications system that permits cerebral activity alone to control computers or external devices. The immediate goal of BCI research is to provide communications capabilities to severely disabled people who are totally paralyzed or ‘locked in’ by neurological neuromuscular disorders, such as amyotrophic lateral sclerosis, brain stem stroke, or spinal cord injury. Here, we review the state-of-the-art of BCIs, looking at the different steps that form a standard BCI: signal acquisition, preprocessing or signal enhancement, feature extraction, classification and the control interface. We discuss their advantages, drawbacks, and latest advances, and we survey the numerous technologies reported in the scientific literature to design each step of a BCI. First, the review examines the neuroimaging modalities used in the signal acquisition step, each of which monitors a different functional brain activity such as electrical, magnetic or metabolic activity. Second, the review discusses different electrophysiological control signals that determine user intentions, which can be detected in brain activity. Third, the review includes some techniques used in the signal enhancement step to deal with the artifacts in the control signals and improve the performance. Fourth, the review studies some mathematic algorithms used in the feature extraction and classification steps which translate the information in the control signals into commands that operate a computer or other device. Finally, the review provides an overview of various BCI applications that control a range of devices. PMID:22438708

  18. Micromachined devices for interfacing neurons

    NASA Astrophysics Data System (ADS)

    Stieglitz, Thomas; Beutel, Hansjoerg; Blau, Cornelia; Meyer, Joerg-Uwe

    1998-07-01

    Micromachining technologies were established to fabricate microelectrode arrays and devices for interfacing parts of the central or peripheral nervous system. The devices were part of a neural prosthesis that allows simultaneous multichannel recording and multisite stimulation of neurons. Overcoming the brittle mechanics of silicon devices and challenging housing demands close to the nerve we established a process technology to fabricate light-weighted and highly flexible polyimide based devices. Platinum and iridium thin-film electrodes were embedded in the polyimide. With reactive ion etching we got the possibility to simply integrate interconnections and to form nearly arbitrary outer shapes of the devices. We designed multichannel devices with up to 24 electrodes in the shape of plates, hooks and cuffs for different applications. In vitro tests exhibited stable electrode properties and no cytotoxicity of the materials and the devices. Sieve electrodes were chronically implanted in rats to interface the regenerating sciatic nerve. After six months, recordings and stimulation of the nerve via electrodes on the micro-device proved functional reinnervation of the limb. Concentric circular structures were designed for a retina implant for the blind. In preliminary studies in rabbits, evoked potentials in the visual cortex corresponded to stimulation sites of the implant.

  19. Brain computer interfaces, a review.

    PubMed

    Nicolas-Alonso, Luis Fernando; Gomez-Gil, Jaime

    2012-01-01

    A brain-computer interface (BCI) is a hardware and software communications system that permits cerebral activity alone to control computers or external devices. The immediate goal of BCI research is to provide communications capabilities to severely disabled people who are totally paralyzed or 'locked in' by neurological neuromuscular disorders, such as amyotrophic lateral sclerosis, brain stem stroke, or spinal cord injury. Here, we review the state-of-the-art of BCIs, looking at the different steps that form a standard BCI: signal acquisition, preprocessing or signal enhancement, feature extraction, classification and the control interface. We discuss their advantages, drawbacks, and latest advances, and we survey the numerous technologies reported in the scientific literature to design each step of a BCI. First, the review examines the neuroimaging modalities used in the signal acquisition step, each of which monitors a different functional brain activity such as electrical, magnetic or metabolic activity. Second, the review discusses different electrophysiological control signals that determine user intentions, which can be detected in brain activity. Third, the review includes some techniques used in the signal enhancement step to deal with the artifacts in the control signals and improve the performance. Fourth, the review studies some mathematic algorithms used in the feature extraction and classification steps which translate the information in the control signals into commands that operate a computer or other device. Finally, the review provides an overview of various BCI applications that control a range of devices.

  20. Hydrothermal cement/metal interfaces

    SciTech Connect

    Sugama, Toshifumi; Baldwin, S.

    1996-01-01

    The authors investigated the adherence of two cementitious materials, calcium phosphate cement (CPC) and silica flour-filled class G cement (CGC), to metal substrates, such as cold-rolled steel (CRS), stainless steel (SS), electroplated zinc-coated steel (EZS), and zinc phosphate-coated steel (ZPS) after autoclaving at 200 C. In CPC/metal joints, the {gamma}-AlOOH phase, which segregated from the hydroxyapatite phase of the CPC matrix, was preferentially precipitated on the CRS and SS surfaces and also mixed with the reaction products formed at the interfaces between CPC and EZS or ZPS. Precipitation of {gamma}-AlOOH caused the formation of a weak boundary layer at the interfacial transition zones, thereby resulting in a low shear-bond strength. Although CGC accelerated the rate of corrosion of CRS and SS surfaces, the growth of Fe{sub 2}O{sub 3} clusters, formed as the corrosion products of metals at interfaces, aided the anchoring effect of xonotlite crystals as the major phase of CGC matrix, thereby conferring a high shear-bond strength. The EZS and ZPS surfaces were susceptible to alkali dissolution caused by the attack of the high-pH interstitial fluid of CGC pastes to the Zn and zinc phosphate coatings. Thus, the bond strengths of the CGC/EZS and /ZPS joints were lower than those of the joints made with CRS and SS.

  1. The interactive digital video interface

    NASA Technical Reports Server (NTRS)

    Doyle, Michael D.

    1989-01-01

    A frequent complaint in the computer oriented trade journals is that current hardware technology is progressing so quickly that software developers cannot keep up. A example of this phenomenon can be seen in the field of microcomputer graphics. To exploit the advantages of new mechanisms of information storage and retrieval, new approaches must be made towards incorporating existing programs as well as developing entirely new applications. A particular area of need is the correlation of discrete image elements to textural information. The interactive digital video (IDV) interface embodies a new concept in software design which addresses these needs. The IDV interface is a patented device and language independent process for identifying image features on a digital video display and which allows a number of different processes to be keyed to that identification. Its capabilities include the correlation of discrete image elements to relevant text information and the correlation of these image features to other images as well as to program control mechanisms. Sophisticated interrelationships can be set up between images, text, and program control mechanisms.

  2. Tailoring thermal interfaces with nanomaterials

    NASA Astrophysics Data System (ADS)

    Seshadri, Indira

    Thermal interfaces are key to ensure the reliable performance of many semiconductor, energy and electronic systems. High thermal conductivity (k), low elastic modulus (E) interface materials are required to dissipate heat and relieve thermo-mechanical stresses. The aim of this thesis is to develop compliant, high k nanocomposite materials for thermal interface applications utilizing nanostructured networks. Realizing high k nanocomposites is a challenge because of difficulties in incorporating high fractions of uniformly dispersed nanofillers and countering low filler-matrix interfacial conductance, while retaining a low elastic modulus. In this thesis, it is demonstrated that these issues are obviated by using < 5 volume % sub-10-nm cold welded gold nanowire fillers to obtain an unprecedented 30-fold increase in polydimethylsiloxane thermal conductivity that is 6-fold higher than previously reported nanocomposites at low nanofiller loadings and exceeds theoretical predictions. The nanowire diameter and aspect ratio are key to obtain cold-welded networks that enhance k at low filler fractions, while fostering low E. Along with high k, tailoring high thermal contact conductance G c is crucial for many applications. This thesis reveals a critical correlation between the rheological behavior of a high k gold-nanowire-filled polydimethylsiloxane nanocomposite and its thermal contact conductance with copper. At a critical filler fraction, an abrupt increase in the nanocomposite k is accompanied by a liquid-solid transition and a multifold decrease in Gc. These concurrent changes are attributed to nanowire percolation network formation and pre-cure polymer gelation that inhibits the formation of conformal void-free interfaces. These findings will be important for designing processing sequences to realize heterointerfaces with nanowire filled high k nanocomposite materials. Another important finding of this thesis is that nanowire networks can result in mechanical

  3. Microfluidic PMMA interfaces for rectangular glass capillaries

    NASA Astrophysics Data System (ADS)

    Evander, Mikael; Tenje, Maria

    2014-02-01

    We present the design and fabrication of a polymeric capillary fluidic interface fabricated by micro-milling. The design enables the use of glass capillaries with any kind of cross-section in complex microfluidic setups. We demonstrate two different designs of the interface; a double-inlet interface for hydrodynamic focusing and a capillary interface with integrated pneumatic valves. Both capillary interfaces are presented together with examples of practical applications. This communication shows the design optimization and presents details of the fabrication process. The capillary interface opens up for the use of complex microfluidic systems in single-use glass capillaries. They also enable simple fabrication of glass/polymer hybrid devices that can be beneficial in many research fields where a pure polymer chip negatively affects the device's performance, e.g. acoustofluidics.

  4. Imaging Macromolecular Interactions at an Interface

    PubMed Central

    Lampe, Joshua W.; Liao, Zhengzheng; Dmochowski, Ivan J.; Ayyaswamy, Portonovo S.; Eckmann, David M.

    2010-01-01

    Important physiological, pathological, and technological processes occur at continuous and dispersed phase interfaces. Understanding these processes is limited by inability to quantitate molecular events occurring at the interface. To provide a model-independent measurement of protein concentration and mobility at the interface, we employed confocal laser scanning microscopy (CLSM). Fluorescently labeled albumin and fibrinogen were studied singly, pairwise, and with a surfactant, Pluronic F-127, in aqueous droplets. CLSM enables measurement of molecular behaviors manifest as surface inhomogeneity and of biophysical quantities including partitioning between the bulk and the gas-liquid (GL) interface. We conclude that albumin and fibrinogen behave substantially differently at the GL interface, that adsorption from multi-species solutions is fundamentally different than adsorption from solutions of single species, and surfactants can inhibit proteins from occupying the interface. PMID:20085337

  5. Imaging macromolecular interactions at an interface.

    PubMed

    Lampe, Joshua W; Liao, Zhengzheng; Dmochowski, Ivan J; Ayyaswamy, Portonovo S; Eckmann, David M

    2010-02-16

    Important physiological, pathological, and technological processes occur at continuous and dispersed phase interfaces. Understanding these processes is limited by inability to quantitate molecular events occurring at the interface. To provide a model-independent measurement of protein concentration and mobility at the interface, we employed confocal laser scanning microscopy (CLSM). Fluorescently labeled albumin and fibrinogen were studied singly, pairwise, and with a surfactant, Pluronic F-127, in aqueous droplets. CLSM enables measurement of molecular behaviors manifest as surface inhomogeneity and of biophysical quantities including partitioning between the bulk and the gas-liquid (GL) interface. We conclude that albumin and fibrinogen behave substantially differently at the GL interface, adsorption from multispecies solutions is fundamentally different than adsorption from solutions of single species, and surfactants can inhibit proteins from occupying the interface.

  6. Development of a simulated smart pump interface.

    PubMed

    Elias, Beth L; Moss, Jacqueline A; Shih, Alan; Dillavou, Marcus

    2014-01-01

    Medical device user interfaces are increasingly complex, resulting in a need for evaluation in clinicallyaccurate settings. Simulation of these interfaces can allow for evaluation, training, and use for research without the risk of harming patients and with a significant cost reduction over using the actual medical devices. This pilot project was phase 1 of a study to define and evaluate a methodology for development of simulated medical device interface technology to be used for education, device development, and research. Digital video and audio recordings of interface interactions were analyzed to develop a model of a smart intravenous medication infusion pump user interface. This model was used to program a high-fidelity simulated smart intravenous medication infusion pump user interface on an inexpensive netbook platform.

  7. Electronic Interfacing with Living Cells

    NASA Astrophysics Data System (ADS)

    Fleming, James T.

    The direct interfacing of living cells with inorganic electronic materials, components or systems has led to the development of two broad categories of devices that can (1) transduce biochemical signals generated by biological components into electrical signals and (2) transduce electronically generated signals into biochemical signals. The first category of devices permits the monitoring of living cells, the second, enables control of cellular processes. This review will survey this exciting area with emphasis on the fundamental issues and obstacles faced by researchers. Devices and applications that use both prokaryotic (microbial) and eukaryotic (mammalian) cells will be covered. Individual devices described include microbial biofuel cells that produce electricity, bioelectrical reactors that enable electronic control of cellular metabolism, living cell biosensors for the detection of chemicals and devices that permit monitoring and control of mammalian physiology.

  8. General purpose intelligent sensor interface

    NASA Technical Reports Server (NTRS)

    Mckee, J. W.

    1990-01-01

    The long range goal is to develop an intelligent sensor system that will simplify the design and development of expert systems that use sensors of physical phenomena as a source of input data. This phase of the research concentrated on the integration of image processing sensors with expert system environments. The anticipated result of this research is the ability to design systems in which the user will not need to be an expert in such areas as image processing algorithms, local area networks, image processor hardware selection or interfacing, or television cameras selection. The user will be able to access data from video sensors through standard expert system statements without any need to know about the sensor hardware or software.

  9. Conduction at a ferroelectric interface

    SciTech Connect

    Marshall, Matthew S. J.; Malashevich, Andrei; Disa, Ankit S.; Han, Myung -Geun; Chen, Hanghui; Zhu, Yimei; Ismail-Beigi, Sohrab; Walker, Frederick J.; Ahn, Charles H.

    2014-11-05

    Typical logic elements utilizing the field effect rely on the change in carrier concentration due to the field in the channel region of the device. Ferroelectric-field-effect devices provide a nonvolatile version of this effect due to the stable polarization order parameter in the ferroelectric. In this study, we describe an oxide/oxide ferroelectric heterostructure device based on (001)-oriented PbZr₀̣.₂Ti₀.₈O₃-LaNiO₃ where the dominant change in conductivity is a result of a significant mobility change in the interfacial channel region. The effect is confined to a few atomic layers at the interface and is reversible by switching the ferroelectric polarization. More interestingly, in one polarization state, the field effect induces a 1.7 eV shift of the interfacial bands to create a new conducting channel in the interfacial PbO layer of the ferroelectric.

  10. Conduction at a ferroelectric interface

    DOE PAGES

    Marshall, Matthew S. J.; Malashevich, Andrei; Disa, Ankit S.; ...

    2014-11-05

    Typical logic elements utilizing the field effect rely on the change in carrier concentration due to the field in the channel region of the device. Ferroelectric-field-effect devices provide a nonvolatile version of this effect due to the stable polarization order parameter in the ferroelectric. In this study, we describe an oxide/oxide ferroelectric heterostructure device based on (001)-oriented PbZr₀̣.₂Ti₀.₈O₃-LaNiO₃ where the dominant change in conductivity is a result of a significant mobility change in the interfacial channel region. The effect is confined to a few atomic layers at the interface and is reversible by switching the ferroelectric polarization. More interestingly, inmore » one polarization state, the field effect induces a 1.7 eV shift of the interfacial bands to create a new conducting channel in the interfacial PbO layer of the ferroelectric.« less

  11. CONDUIT: Control Designer's Unified Interface

    NASA Technical Reports Server (NTRS)

    Levine, William S.; Tischler, Mark B.

    1999-01-01

    CONDUIT, which stands for control designer's unified interface, is a computer software package. Its purpose is to assist a human control system designer in designing control systems for aircraft. At the present time CONDUIT is being used by most of the major U. S. rotorcraft and fixed-wing aircraft manufacturers to assist in the design of stability and control augmentation systems. Work is also continuing on the development of additional features for CONDUIT, including tools for analyzing the sensitivity of solutions, and on further enhancements to the basic package. The purpose of this paper is to describe CONDUIT, its operation, and the sensitivity tools that are being developed for inclusion in the next release of the package.

  12. Cooperative strings and glassy interfaces.

    PubMed

    Salez, Thomas; Salez, Justin; Dalnoki-Veress, Kari; Raphaël, Elie; Forrest, James A

    2015-07-07

    We introduce a minimal theory of glass formation based on the ideas of molecular crowding and resultant string-like cooperative rearrangement, and address the effects of free interfaces. In the bulk case, we obtain a scaling expression for the number of particles taking part in cooperative strings, and we recover the Adam-Gibbs description of glassy dynamics. Then, by including thermal dilatation, the Vogel-Fulcher-Tammann relation is derived. Moreover, the random and string-like characters of the cooperative rearrangement allow us to predict a temperature-dependent expression for the cooperative length ξ of bulk relaxation. Finally, we explore the influence of sample boundaries when the system size becomes comparable to ξ. The theory is in agreement with measurements of the glass-transition temperature of thin polymer films, and allows quantification of the temperature-dependent thickness hm of the interfacial mobile layer.

  13. [Pathology of the vitreomacular interface].

    PubMed

    Pop, Monica; Gheorghe, Alina

    2014-01-01

    Vitreous role in the pathophysiology of retinal diseases has increased importantly over the recent years. This was possible using Optical Coherence Tomography which reviewed the way the vitreoretinal interface should be looked at and defined and classified new pathologies such as Vitreoretinal Traction Syndrome. Vitreous is not an empty space but an important anatomical structure with role in ocular physiology. With age biochemical changes occur so that vitreous starts to liquefy. Once the vitreous is liquefied (sinchisis) it collapses and passes in the retrohialoid space (sineresis). In complete PVD besides sinchisis there is a weakness of the adherence between the posterior cortex and ILM with total detachment of posterior cortex. Abnormal adhesions are associated with incomplete PVD. The definition and understanting of vitreoretinal pathology is an active and continuous process, PVD being the trigger of a lot of retinal pathologies: epiretinal membrane, macular hole, tractional macular oedema, VMTS, myopic traction maculopathy, exacerbations of exudative ARMD.

  14. Interface area transport of monodispersed spherical particulates

    SciTech Connect

    Chang, Chong H.

    2016-08-05

    We present an interface area transport model required in tracking of mass, momentum, and energy exchange between dispersed and background materials. The basic transport equation has been rigorously derived from the volume fraction evolution equation. Interface area changes due to mass transport and local compression/expansion are included. The model is then simplified for the case in which the dispersed phase is composed of spheres of locally uniform size. A procedure for calculating advective flux with interface reconstruction has been suggested.

  15. Neuroengineering: building interfaces from neurons to brain.

    PubMed

    Thakor, Nitish V

    2008-01-01

    Neuroengineering is emerging as an exciting new field with wide ranging research opportunities to contribute to both basic and clinical neurosciences. Armed with training and diverse research tools, engineers are now contributing to technologies to interface to neurons and to the whole brain. The research on modern neural and brain interface technologies has culminated in very recent, exciting programs to develop brain-machine interfaces such as neutrally controlled prostheses.

  16. Interface For Color-Video Monitor

    NASA Technical Reports Server (NTRS)

    Rodriguez, Eric

    1987-01-01

    Commercially produced color-video monitor modified by addition of interface circuit to accommodate wider-than-usual range of scanning rates and resolutions. Interface circuit measures frequencies of horizontal- and vertical-synchronizing pulses. When frequencies fall within combination of preset ranges, interface generates associated preset combination of eight picture-adjusting signals. Video monitor "trained" by computer that helps to control calibration procedure and inserts values in calibration tables.

  17. Workload-Based Automated Interface Mode Selection

    DTIC Science & Technology

    2012-03-22

    Exposing more control and information gives the operator the ability to understand the state of the system better and take more complex actions, but at the...and require fast response, and may be a better target for these types of interface features. Many computer games already use adaptive interfaces to...introduces an agent into the system interface to assume responsibility for man- aging automation mode selection. The agent uses a novel dynamic scheme for

  18. Network interface unit design options performance analysis

    NASA Technical Reports Server (NTRS)

    Miller, Frank W.

    1991-01-01

    An analysis is presented of three design options for the Space Station Freedom (SSF) onboard Data Management System (DMS) Network Interface Unit (NIU). The NIU provides the interface from the Fiber Distributed Data Interface (FDDI) local area network (LAN) to the DMS processing elements. The FDDI LAN provides the primary means for command and control and low and medium rate telemetry data transfers on board the SSF. The results of this analysis provide the basis for the implementation of the NIU.

  19. Recent work on material interface reconstruction

    SciTech Connect

    Mosso, S.J.; Swartz, B.K.

    1997-12-31

    For the last 15 years, many Eulerian codes have relied on a series of piecewise linear interface reconstruction algorithms developed by David Youngs. In a typical Youngs` method, the material interfaces were reconstructed based upon nearly cell values of volume fractions of each material. The interfaces were locally represented by linear segments in two dimensions and by pieces of planes in three dimensions. The first step in such reconstruction was to locally approximate an interface normal. In Youngs` 3D method, a local gradient of a cell-volume-fraction function was estimated and taken to be the local interface normal. A linear interface was moved perpendicular to the now known normal until the mass behind it matched the material volume fraction for the cell in question. But for distorted or nonorthogonal meshes, the gradient normal estimate didn`t accurately match that of linear material interfaces. Moreover, curved material interfaces were also poorly represented. The authors will present some recent work in the computation of more accurate interface normals, without necessarily increasing stencil size. Their estimate of the normal is made using an iterative process that, given mass fractions for nearby cells of known but arbitrary variable density, converges in 3 or 4 passes in practice (and quadratically--like Newton`s method--in principle). The method reproduces a linear interface in both orthogonal and nonorthogonal meshes. The local linear approximation is generally 2nd-order accurate, with a 1st-order accurate normal for curved interfaces in both two and three dimensional polyhedral meshes. Recent work demonstrating the interface reconstruction for curved surfaces will /be discussed.

  20. Flexible feature interface for multimedia sources

    DOEpatents

    Coffland, Douglas R.

    2009-06-09

    A flexible feature interface for multimedia sources system that includes a single interface for the addition of features and functions to multimedia sources and for accessing those features and functions from remote hosts. The interface utilizes the export statement: export "C" D11Export void FunctionName(int argc, char ** argv,char * result, SecureSession *ctrl) or the binary equivalent of the export statement.

  1. New User Interface Capabilities for Control Systems

    SciTech Connect

    Kasemir, Kay

    2009-01-01

    Latest technologies promise new control system User Interface (UI) features and greater interoperability of applications. New developments using Java and Eclipse aim to unify diverse control systems and make communication between applications seamless. Web based user interfaces can improve portability and remote access. Modern programming tools improve efficiency, support testing and facilitate shared code. This paper will discuss new developments aimed at improving control system interfaces and their development environment.

  2. Nonequilibrium interfaces in colloidal fluids

    NASA Astrophysics Data System (ADS)

    Bier, Markus; Arnold, Daniel

    2013-12-01

    The time-dependent structure, interfacial tension, and evaporation of an oversaturated colloid-rich (liquid) phase in contact with an undersaturated colloid-poor (vapor) phase of a colloidal dispersion is investigated theoretically during the early-stage relaxation, where the interface is relaxing towards a local equilibrium state while the bulk phases are still out of equilibrium. Since systems of this type exhibit a clear separation of colloidal and solvent relaxation time scales with typical times of interfacial tension measurements in between, they can be expected to be suitable for analogous experimental studies, too. The major finding is that, irrespective of how much the bulk phases differ from two-phase coexistence, the interfacial structure and the interfacial tension approach those at two-phase coexistence during the early-stage relaxation process. This is a surprising observation since it implies that the relaxation towards global equilibrium of the interface is not following but preceding that of the bulk phases. Scaling forms for the local chemical potential, the flux, and the dissipation rate exhibit qualitatively different leading order contributions depending on whether an equilibrium or a nonequilibrium system is considered. The degree of nonquilibrium between the bulk phases is found to not influence the qualitative relaxation behavior (i.e., the values of power-law exponents), but to determine the quantitative deviation of the observed quantities from their values at two-phase coexistence. Whereas the underlying dynamics differs between colloidal and molecular fluids, the behavior of quantities such as the interfacial tension approaching the equilibrium values during the early-stage relaxation process, during which nonequilibrium conditions of the bulk phases are not changed, can be expected to occur for both types of systems.

  3. On Building a Search Interface Discovery System

    NASA Astrophysics Data System (ADS)

    Shestakov, Denis

    A huge portion of the Web known as the deep Web is accessible via search interfaces to myriads of databases on the Web. While relatively good approaches for querying the contents of web databases have been recently proposed, one cannot fully utilize them having most search interfaces unlocated. Thus, the automatic recognition of search interfaces to online databases is crucial for any application accessing the deep Web. This paper describes the architecture of the I-Crawler, a system for finding and classifying search interfaces. The I-Crawler is intentionally designed to be used in the deep web characterization surveys and for constructing directories of deep web resources.

  4. Hydrothermal synthesis, structures and optical properties of A2Zn3(SeO3)4·XH2O (A=Li, Na, K; X=2 or 0)

    NASA Astrophysics Data System (ADS)

    Liu, Yunsheng; Mei, Dajiang; Xu, Jingli; Wu, Yuandong

    2015-12-01

    New alkali metal zinc selenites, A2Zn3(SeO3)4·XH2O (A=Li, Na, K; X=2 or 0) were prepared through hydrothermal reactions. Li2Zn3(SeO3)4·2H2O (1) crystallizes in the monoclinic space group P21/c with lattice parameters a=8.123(4), b=9.139(4), c=7.938(3) Å, β=112.838(9)°. Na2Zn3(SeO3)4·2H2O (2) crystallizes in the monoclinic space group C2/c with lattice parameters a=15.7940(18), b=6.5744(8), c=14.6787(17) Å, β=107.396(3)°. K2Zn3(SeO3)4 (3) crystallizes in the monoclinic space group C2/c with lattice parameters a=11.3584(12), b=8.6091(9), c=13.6816(14) Å, β=93.456(2)°. The anionic structures are composed of [Zn3O12]18- sheets, chains, and "isolated" units in compound 1, 2, 3, respectively, and trigonal pyramids SeO32-. The compounds were characterized by the solid state UV-vis-NIR diffuse reflectance spectroscopy, infrared spectra and thermogravimetric analysis.

  5. Crystal structure and ionic conductivity of ruthenium diphosphate ARu{sub 2}(P{sub 2}O{sub 7}){sub 2}, A=Li, Na, and Ag, with a tunnel structure

    SciTech Connect

    Fukuoka, Hiroshi; Matsunaga, Hideyuki; Yamanaka, Shoji

    2003-05-26

    Crystal structure and ionic conductivity of ruthenium diphosphates, ARu{sub 2}(P{sub 2}O{sub 7}){sub 2} A=Li, Na, and Ag, were investigated. The structure of the Ag compound was determined by single crystal X-ray diffraction techniques. It crystallized in the triclinic space group P-1 with a=4.759(2) A, b=6.843(2) A, c=8.063(1) A, {alpha}=90.44(2) deg., {beta}=92.80(2) deg., {gamma}=104.88(2) deg., V=253.4(1) A{sup 3}. The host structure of it was composed of RuO{sub 6} and P{sub 2}O{sub 7} groups and formed tunnels running along the a-axis, in which Ag{sup +} ions were situated. The ionic conductivities have been measured on pellets of the polycrystalline powders. The Li and Ag compounds showed the conductivities of 1.0x10{sup -4} and 3.5x10{sup -5} S cm{sup -1} at 150 deg. C, respectively. Magnetic susceptibility measurement of the Ag compound showed that it did not obey the Curie-Weiss law and the effective magnetic moment decreased as temperature decreased due to the large spin-orbital coupling effect of Ru{sup 4+} ions.

  6. An interface energy density-based theory considering the coherent interface effect in nanomaterials

    NASA Astrophysics Data System (ADS)

    Yao, Yin; Chen, Shaohua; Fang, Daining

    2017-02-01

    To characterize the coherent interface effect conveniently and feasibly in nanomaterials, a continuum theory is proposed that is based on the concept of the interface free energy density, which is a dominant factor affecting the mechanical properties of the coherent interface in materials of all scales. The effect of the residual strain caused by self-relaxation and the lattice misfit of nanomaterials, as well as that due to the interface deformation induced by an external load on the interface free energy density is considered. In contrast to the existing theories, the stress discontinuity at the interface is characterized by the interface free energy density through an interface-induced traction. As a result, the interface elastic constant introduced in previous theories, which is not easy to determine precisely, is avoided in the present theory. Only the surface energy density of the bulk materials forming the interface, the relaxation parameter induced by surface relaxation, and the mismatch parameter for forming a coherent interface between the two surfaces are involved. All the related parameters are far easier to determine than the interface elastic constants. The effective bulk and shear moduli of a nanoparticle-reinforced nanocomposite are predicted using the proposed theory. Closed-form solutions are achieved, demonstrating the feasibility and convenience of the proposed model for predicting the interface effect in nanomaterials.

  7. Structural modifications due to interface chemistry at metal-nitride interfaces

    PubMed Central

    Yadav, S. K.; Shao, S.; Wang, J.; Liu, X.-Y.

    2015-01-01

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. Corresponding to structural energies of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces. PMID:26611639

  8. Structural modifications due to interface chemistry at metal-nitride interfaces.

    PubMed

    Yadav, S K; Shao, S; Wang, J; Liu, X-Y

    2015-11-27

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. Corresponding to structural energies of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces.

  9. Structural modifications due to interface chemistry at metal-nitride interfaces

    NASA Astrophysics Data System (ADS)

    Yadav, S. K.; Shao, S.; Wang, J.; Liu, X.-Y.

    2015-11-01

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. Corresponding to structural energies of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces.

  10. Structural modifications due to interface chemistry at metal-nitride interfaces

    DOE PAGES

    Yadav, S. K.; Shao, S.; Wang, J.; ...

    2015-11-27

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. As a result, corresponding to structural energiesmore » of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces.« less

  11. Structural modifications due to interface chemistry at metal-nitride interfaces

    SciTech Connect

    Yadav, S. K.; Shao, S.; Wang, J.; Liu, X. -Y.

    2015-11-27

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. As a result, corresponding to structural energies of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces.

  12. EDITORIAL: Sensors based on interfaces

    NASA Astrophysics Data System (ADS)

    Camassel, Jean; Soukiassian, Patrick G.

    2007-12-01

    Sensors are specific analog devices that convert a physical quantity, like the temperature or external pressure or concentration of carbon monoxide in a confined atmosphere, into an electrical signal. Considered in this way, every sensor is then a part of the artificial interface, which connects the human world to the world of machines. The other side of the interface is represented by actuators. Most often, after processing the data they are used to convert the out-coming electrical power into counteracting physical action. In the last few years, thanks to inexpensive silicon technology, enormous capability for data processing has been developed and the world of machines has become increasingly invasive. The world of sensors has become increasingly complex too. Applications range from classical measurements of the temperature, vibrations, shocks and acceleration to more recent chemical and bio-sensing technologies. Chemical sensors are used to detect the presence of specific, generally toxic, chemical species. To measure their concentration, one uses some specific property, generally a physical one, like the intensity of infrared absorption bands. Bio-sensors are new, more complex, devices that combine a bio-receptor with a physical transducer. The bio-receptor is a molecule (for instance, an enzyme like glucose oxidase) that can recognize a specific target (glucose molecules in the case of glucose oxidase). The enzyme must be fixed on the transducer and, as a consequence of recognition, the transducer must convert the event into a measurable analytical signal. A common feature of many chemical and bio-sensors is that they require a large surface of interaction with the outside world. For that reason and in order to increase efficiency, either nanoparticles or pores or a combination of both, made from various materials including (but not limited to) porous silicon, are often used as the functional transducer interface. The reviews in this Cluster Issue of Journal

  13. Interfacing the expert: Characteristics and requirements for the user interface in expert systems

    NASA Technical Reports Server (NTRS)

    Potter, Andrew

    1987-01-01

    Because expert systems deal with new sets of problems presenting unique interface requirements, special issues requiring special attention are presented to user interface designers. External knowledge representation (how knowdedge is represented across the user interface), modes of user-system interdependence (advisory, cooperative, and autonomous), and management of uncertainty (deciding what actions to take or recommend based on incomplete evidence) are discussed.

  14. Towards an Educational SuperInterface.

    ERIC Educational Resources Information Center

    De Diana, Italo P. F.; White, T. N.

    1994-01-01

    Describes an educational computer network, SuperInterface, that could be used for telestudy for university education. Topics discussed include computer-supported collaborative work; computer-based learning; multimedia databases, or electronic books; human-machine interfaces; hardware, software, and groupware; learners; teachers; organizations and…

  15. Designing a Visual Interface for Online Searching.

    ERIC Educational Resources Information Center

    Lin, Xia

    1999-01-01

    "MedLine Search Assistant" is a new interface for MEDLINE searching that improves both search precision and recall by helping the user convert a free text search to a controlled vocabulary-based search in a visual environment. Features of the interface are described, followed by details of the conceptual design and the physical design of…

  16. User Interface Design for Dynamic Geometry Software

    ERIC Educational Resources Information Center

    Kortenkamp, Ulrich; Dohrmann, Christian

    2010-01-01

    In this article we describe long-standing user interface issues with Dynamic Geometry Software and common approaches to address them. We describe first prototypes of multi-touch-capable DGS. We also give some hints on the educational benefits of proper user interface design.

  17. Hypertext Interface Design and Structural Knowledge Acquisition.

    ERIC Educational Resources Information Center

    Koneman, Philip A.; Jonassen, David H.

    Hypertext is well-suited for educational applications where open learning and knowledge exploration is desired. In such applications, principles of good hypertext interface design should be employed to avoid navigational problems so as to maximize learning. Interface design, however, may also directly enhance acquisition of a particular knowledge…

  18. Utilizing Bayesian Techniques for User Interface Intelligence

    DTIC Science & Technology

    1996-12-01

    rea - soning and knowledge) have placed little or no emphasis on the expert system user interface. These developers spend most resources perfecting the...1994). 24. Cesta, Amedeo and Daniela DAloisi. "Building Interfaces as Personal Assis- tants," SIGCHI Bulletin, 28(3):108-113 (1996). 25. Chappel, H

  19. Development of the Computer Interface Literacy Measure.

    ERIC Educational Resources Information Center

    Turner, G. Marc; Sweany, Noelle Wall; Husman, Jenefer

    2000-01-01

    Discussion of computer literacy and the rapidly changing face of technology focuses on a study that redefined computer literacy to include competencies for using graphical user interfaces for operating systems, hypermedia applications, and the Internet. Describes the development and testing of the Computer Interface Literacy Measure with…

  20. Visual User Interfaces for Information Exploration.

    ERIC Educational Resources Information Center

    Shneiderman, Ben

    1991-01-01

    Discussion of human-computer interfaces focuses on the use of graphical and direct manipulation approaches to improve the user interface. Topics discussed include information seeking; computerized search capabilities, including full-text string searches, index searches, and hypertext; Boolean expressions; dynamic or direct manipulation queries;…