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Sample records for surface components responsible

  1. Response Surface Modeling of Combined-Cycle Propulsion Components using Computational Fluid Dynamics

    Science.gov (United States)

    Steffen, C. J., Jr.

    2002-01-01

    Three examples of response surface modeling with CFD are presented for combined cycle propulsion components. The examples include a mixed-compression-inlet during hypersonic flight, a hydrogen-fueled scramjet combustor during hypersonic flight, and a ducted-rocket nozzle during all-rocket flight. Three different experimental strategies were examined, including full factorial, fractionated central-composite, and D-optimal with embedded Plackett-Burman designs. The response variables have been confined to integral data extracted from multidimensional CFD results. Careful attention to uncertainty assessment and modeling bias has been addressed. The importance of automating experimental setup and effectively communicating statistical results are emphasized.

  2. The contribution of inflammasome components on macrophage response to surface nanotopography and chemistry

    Science.gov (United States)

    Christo, Susan; Bachhuka, Akash; Diener, Kerrilyn R.; Vasilev, Krasimir; Hayball, John D.

    2016-05-01

    Implantable devices have become an established part of medical practice. However, often a negative inflammatory host response can impede the integration and functionality of the device. In this paper, we interrogate the role of surface nanotopography and chemistry on the potential molecular role of the inflammasome in controlling macrophage responses. To achieve this goal we engineered model substrata having precisely controlled nanotopography of predetermined height and tailored outermost surface chemistry. Bone marrow derived macrophages (BMDM) were harvested from genetically engineered mice deficient in the inflammasome components ASC, NLRP3 and AIM2. These cells were then cultured on these nanoengineered substrata and assessed for their capacity to attach and express pro-inflammatory cytokines. Our data provide evidence that the inflammasome components ASC, NLRP3 and AIM2 play a role in regulating macrophage adhesion and activation in response to surface nanotopography and chemistry. The findings of this paper are important for understanding the inflammatory consequences caused by biomaterials and pave the way to the rational design of future implantable devices having controlled and predictable inflammatory outcomes.

  3. Neural Network and Response Surface Methodology for Rocket Engine Component Optimization

    Science.gov (United States)

    Vaidyanathan, Rajkumar; Papita, Nilay; Shyy, Wei; Tucker, P. Kevin; Griffin, Lisa W.; Haftka, Raphael; Fitz-Coy, Norman; McConnaughey, Helen (Technical Monitor)

    2000-01-01

    The goal of this work is to compare the performance of response surface methodology (RSM) and two types of neural networks (NN) to aid preliminary design of two rocket engine components. A data set of 45 training points and 20 test points obtained from a semi-empirical model based on three design variables is used for a shear coaxial injector element. Data for supersonic turbine design is based on six design variables, 76 training, data and 18 test data obtained from simplified aerodynamic analysis. Several RS and NN are first constructed using the training data. The test data are then employed to select the best RS or NN. Quadratic and cubic response surfaces. radial basis neural network (RBNN) and back-propagation neural network (BPNN) are compared. Two-layered RBNN are generated using two different training algorithms, namely solverbe and solverb. A two layered BPNN is generated with Tan-Sigmoid transfer function. Various issues related to the training of the neural networks are addressed including number of neurons, error goals, spread constants and the accuracy of different models in representing the design space. A search for the optimum design is carried out using a standard gradient-based optimization algorithm over the response surfaces represented by the polynomials and trained neural networks. Usually a cubic polynominal performs better than the quadratic polynomial but exceptions have been noticed. Among the NN choices, the RBNN designed using solverb yields more consistent performance for both engine components considered. The training of RBNN is easier as it requires linear regression. This coupled with the consistency in performance promise the possibility of it being used as an optimization strategy for engineering design problems.

  4. Response surface optimization of the medium components for the production of biosurfactants by probiotic bacteria

    NARCIS (Netherlands)

    Rodrigues, L; Teixeira, J; Oliveira, R; van der Mei, HC

    Optimization of the medium for biosurfactants production by probiotic bacteria (Lactococcus lactis 53 and Streptococcus thermophilus A) was carried out using response surface methodology. Both biosurfactants were proved to be growth-associated, thus the desired response selected for the optimization

  5. Application of Response Surface Methodology in Extraction of Bioactive Component from Palm Leaves (Elaeis guineensis

    Directory of Open Access Journals (Sweden)

    Nur Afiqah Arham

    2013-10-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 The hydroxyl groups of the polyphenols are capable to act as reducing agent for reduction reaction. The effect of drying temperature, extraction temperature and extraction duration were evaluated using central composite design which consists of 20 experimental runs. Response surface methodology (RSM was used to estimate the optimum parameters in extracting polyphenols from the palm leaves. The correspondence analysis of the results yielded a quadratic model which can be used to find optimum conditions of extraction process. The optimum extraction condition of drying temperature, extraction temperature and extraction duration are 70°C, at 70°C of 10 minutes, respectively. Total polyphenols were determined by application of the Folin-Ciocalteu micro method and the extract was found contain of 8 mg GAE/g dry palm leaves at optimum conditions. Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Doi: 10.12777/ijse.5.2.95-100 [How to cite this article: Arham, N.A., Mohamad, N.A.N., Jai, J., Krishnan, J., Noorsuhana Mohd Yusof, N.M. (2013. Application of Response Surface Methodology in Extraction of Bioactive Component from Palm Leaves (Elaeis guineensis. International Journal of Science and

  6. Surface mount component jig

    Science.gov (United States)

    Kronberg, James W.

    1990-08-07

    A device for bending and trimming the pins of a dual-inline-package component and the like for surface mounting rather than through mounting to a circuit board comprises, in a first part, in pin cutter astride a holder having a recess for holding the component, a first spring therebetween, and, in a second part, two flat members pivotally interconnected by a hinge and urged to an upward peaked position from a downward peaked position by a second spring. As a downward force is applied to the pin cutter it urges the holder downward, assisted by the first spring and a pair of ridges riding on shoulders of the holder, to carry the component against the upward peaked flat members which guide the pins outwardly. As the holder continues downwardly, the flat members pivot to the downward peaked position bending the pins upwardly against the sides of the holder. When the downward movement is met with sufficient resistance, the ridges of the pin cutter ride over the holder's shoulders to continue downward to cut any excess length of pin.

  7. Optimization of medium components for production of chitin deacetylase byBacillus amyloliquefaciensZ7, using response surface methodology.

    Science.gov (United States)

    He, Yuanhao; Xu, Jianping; Wang, Shengjie; Zhou, Guoying; Liu, Junang

    2014-03-04

    Plackett-Burman design and Box-Behnken response surface methodology (RSM) was employed to optimize the medium components for the chitin deacetylase (CDA) activity from Bacillus amyloliquefaciens Z7. Plackett-Burman design was applied to determine the specific medium components affecting CDA activity and found that starch, chitin and MgSO 4 were critical in augmenting CDA activity. These significant parameters were further optimized using Box-Behnken RSM and the optimum concentrations of starch, chitin and MgSO 4 were found to be 24.4, 8.8 and 0.19 g/L, respectively. The optimum medium composition was chitin 8.8 g/L, starch 24.4 g/L, yeast extract 10g/L, MgSO 4 0.19 g/L, K 2 HPO 4 0.3 g/L and NaCl 5 g/L. Under these optimal conditions, the CDA activity of Bacillus amyloliquefaciens Z7 increased distinctly from 18.75 to 27.48 U/mL (46.6% increase in total yield).

  8. Electrochemical treatment of simulated textile wastewater with industrial components and Levafix Blue CA reactive dye: Optimization through response surface methodology

    International Nuclear Information System (INIS)

    Koerbahti, Bahadir K.; Tanyolac, Abdurrahman

    2008-01-01

    The electrochemical oxidation of simulated textile wastewater was studied on iron electrodes in the presence of NaCl electrolyte in a batch electrochemical reactor. The simulated textile wastewater was prepared from industrial components based on the real mercerized and non-mercerized cotton and viscon process, being first in literature. The highest COD, color and turbidity removals were achieved as 93.9%, 99.5%, and 82.9%, respectively, at 40% pollution load, 8 V applied potential, 37.5 g/L electrolyte concentration and 30 deg. C reaction temperature. The electrochemical treatment of industrial textile wastewater was optimized using response surface methodology (RSM), where applied potential and electrolyte concentration were to be minimized while COD, color and turbidity removal percents were maximized at 100% pollution load. In a specific batch run under the optimum conditions of 30 deg. C reaction temperature, 25 g/L electrolyte concentration and 8 V applied potential applied with 35.5 mA/cm 2 current density at 100% pollution load, COD, color and turbidity removals were realized as 61.6%, 99.6% and 66.4%, respectively

  9. [Optimization for supercritical CO2 extraction with response surface methodology and component analysis of Sapindus mukorossi oil].

    Science.gov (United States)

    Wu, Yan; Xiao, Xin-yu; Ge, Fa-huan

    2012-02-01

    To study the extraction conditions of Sapindus mukorossi oil by Supercritical CO2 Extraction and identify its components. Optimized SFE-CO2 Extraction by response surface methodology and used GC-MS to analysie Sapindus mukorossi oil compounds. Established the model of an equation for the extraction rate of Sapindus mukorossi oil by Supercritical CO2 Extraction, and the optimal parameters for the Supercritical CO2 Extraction determined by the equation were: the extraction pressure was 30 MPa, temperature was 40 degrees C; The separation I pressure was 14 MPa, temperature was 45 degrees C; The separation II pressure was 6 MPa, temperature was 40 degrees C; The extraction time was 60 min and the extraction rate of Sapindus mukorossi oil of 17.58%. 22 main compounds of Sapindus mukorossi oil extracted by supercritical CO2 were identified by GC-MS, unsaturated fatty acids were 86.59%. This process is reliable, safe and with simple operation, and can be used for the extraction of Sapindus mukorossi oil.

  10. Application of Box-Behnken Design and Response Surface Methodology for Surface Roughness Prediction Model of CP-Ti Powder Metallurgy Components Through WEDM

    Science.gov (United States)

    Das, Arunangsu; Sarkar, Susenjit; Karanjai, Malobika; Sutradhar, Goutam

    2018-04-01

    The present work was undertaken to investigate and characterize the machining parameters (such as surface roughness, etc.) of uni-axially pressed commercially pure titanium sintered powder metallurgy components. Powder was uni-axially pressed at designated pressure of 840 MPa to form cylindrical samples and the green compacts were sintered at 0.001 mbar for about 4 h with sintering temperature varying from 1350 to 1450 °C. The influence of the sintering temperature, pulse-on and pulse-off time at wire-EDM on the surface roughness of the preforms has been investigated thoroughly. Experiments were conducted under different machining parameters in a CNC operated wire-cut EDM. The surface roughness of the machined surface was measured and critically analysed. The optimum surface roughness was achieved under the conditions of 6 μs pulse-on time, 9 μs pulse-off time and at sintering temperature of 1450 °C.

  11. Application of Box-Behnken Design and Response Surface Methodology for Surface Roughness Prediction Model of CP-Ti Powder Metallurgy Components Through WEDM

    Science.gov (United States)

    Das, Arunangsu; Sarkar, Susenjit; Karanjai, Malobika; Sutradhar, Goutam

    2017-06-01

    The present work was undertaken to investigate and characterize the machining parameters (such as surface roughness, etc.) of uni-axially pressed commercially pure titanium sintered powder metallurgy components. Powder was uni-axially pressed at designated pressure of 840 MPa to form cylindrical samples and the green compacts were sintered at 0.001 mbar for about 4 h with sintering temperature varying from 1350 to 1450 °C. The influence of the sintering temperature, pulse-on and pulse-off time at wire-EDM on the surface roughness of the preforms has been investigated thoroughly. Experiments were conducted under different machining parameters in a CNC operated wire-cut EDM. The surface roughness of the machined surface was measured and critically analysed. The optimum surface roughness was achieved under the conditions of 6 μs pulse-on time, 9 μs pulse-off time and at sintering temperature of 1450 °C.

  12. Effects and Interactions of Medium Components on Laccase from a Marine-Derived Fungus Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Chandralata Raghukumar

    2009-11-01

    Full Text Available The effects of various synthetic medium components and their interactions with each other ultimately impact laccase production in fungi. This was studied using a laccasehyper-producing marine-derived basidiomycete, Cerrena unicolor MTCC 5159. Inducible laccases were produced in the idiophase only after addition of an inducer such as CuSO4. Concentration of carbon and nitrogen acted antagonistically with respect to laccase production. A combination of low nitrogen and high carbon concentration favored both biomass and laccase production. The most favorable combination resulted in 917 U L-1 of laccase. After sufficient growth had occurred, addition of a surfactant such as Tween 80 positively impacted biomass and increased the laccase activity to around 1,300 U L-1. Increasing the surface to volume ratio of the culture vessel further increased its activity to almost 2,000 U L-1.

  13. In Vitro Propagation of Pink Lapacho: Response Surface Methodology and Factorial Analysis for Optimisation of Medium Components

    Directory of Open Access Journals (Sweden)

    Ezequiel Enrique Larraburu

    2012-01-01

    Full Text Available Handroanthus impetiginosus, pink lapacho, is a timber, ornamental, and medicinal tree. Experiments on the in vitro propagation of H. impetiginosus were conducted using nodal segments cultivated in both Murashige and Skoog salts with Gamborg vitamins (MSG and Woody Plant Medium (WPM with different concentrations of 6-benzylaminopurine (BA and indole butyric acid (IBA. Morphogenic responses were differentially affected by salt compositions and their interactions with plant growth regulators in each micropropagation stage. According to response surface analysis, the optimum multiplication rate with 1 μM IBA ranged from 16.7 to 21.3 μM BA in WPM, and the inhibitors of endogenous auxins could increase multiplication rates. A pulse with 50 μM IBA in 1/2 MSG produced 83% rooting with 3.2 roots per shoots and higher fresh and dry weights of shoots and roots. In the acclimatisation stage, 50% of plants survived after 1 year. This methodology optimised the culture media for the in vitro propagation of the H. impetiginosus clonal pool and could be applied to related species, several of which are categorised as vulnerable on the International Union for the Conservation of Nature Red List.

  14. Effects and interactions of medium components on laccase from a marine-derived fungus using response surface methodology

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza-Ticlo, D.; Garg, S.; Raghukumar, C.

    The effects of various synthetic medium components and their interactions with each other ultimately impact laccase production in fungi. This was studied using a laccase-hyper-producing marine-derived basidiomycete, Cerrena unicolor MTCC 5159...

  15. Response Surface Methodology

    NARCIS (Netherlands)

    Kleijnen, Jack P.C.

    2014-01-01

    Abstract: This chapter first summarizes Response Surface Methodology (RSM), which started with Box and Wilson’s article in 1951 on RSM for real, non-simulated systems. RSM is a stepwise heuristic that uses first-order polynomials to approximate the response surface locally. An estimated polynomial

  16. Response surface methodolgy

    NARCIS (Netherlands)

    Kleijnen, J.P.C.; Fu, Michael C.

    2015-01-01

    This chapter first summarizes Response Surface Methodology (RSM), which started with Box and Wilson’s 1951 article on RSM for real, non-simulated systems. RSM is a stepwise heuristic that uses first-order polynomials to approximate the response surface locally. An estimated polynomial metamodel

  17. Progressive Response Surfaces

    Science.gov (United States)

    Romero, V. J.; Swiler, L. P.

    2004-01-01

    Response surface functions are often used as simple and inexpensive replacements for computationally expensive computer models that simulate the behavior of a complex system over some parameter space. Progressive response surfaces are ones that are built up progressively as global information is added from new sample points in the parameter space. As the response surfaces are globally upgraded based on new information, heuristic indications of the convergence of the response surface approximation to the exact (fitted) function can be inferred. Sampling points can be incrementally added in a structured fashion, or in an unstructured fashion. Whatever the approach, at least in early stages of sampling it is usually desirable to sample the entire parameter space uniformly. At later stages of sampling, depending on the nature of the quantity being resolved, it may be desirable to continue sampling uniformly over the entire parameter space (Progressive response surfaces), or to switch to a focusing/economizing strategy of preferentially sampling certain regions of the parameter space based on information gained in early stages of sampling (Adaptive response surfaces). Here we consider Progressive response surfaces where a balanced indication of global response over the parameter space is desired.We use a variant of Moving Least Squares to fit and interpolate structured and unstructured point sets over the parameter space. On a 2-D test problem we compare response surface accuracy for three incremental sampling methods: Progressive Lattice Sampling; Simple-Random Monte Carlo; and Halton Quasi-Monte-Carlo sequences. We are ultimately after a system for constructing efficiently upgradable response surface approximations with reliable error estimates.

  18. Enhanced mycelial biomass production of the hairy bracket mushroom, Trametes hirsuta (Higher Basidiomycetes), by optimizing medium component with Plackett-Burman design and response surface methodology.

    Science.gov (United States)

    Yang, Rongling; Liu, Xueming; Zhao, Xiangjie; Xu, Yujuan; Ma, Rongxia

    2013-01-01

    Statistical analyses based on experimental designs were applied to optimize the medium components for mycelial biomass production by Trametes hirsuta in shake flask cultivation. First, the effects of different carbon resources (glucose, sucrose, lactose, maltose, fructose, soluble starch and potato), nitrogen resources (yeast extract, peptone, (NH4)2SO4, NH4NO3, NH4Cl, peanut powder, soybean powder) and mineral elements (CaCl2, ZnSO4·7H2O, FeSO4·7H2O, MnSO4·H2O, CuSO4·7H2O) on mycelial biomass production were investigated using a univariate design. Second, a Plackett-Burman design was applied to identify the significant variables that principally influenced the mycelial biomass production, and the path of steepest ascent was pursued to approach the regions of optimal value of the significant variables. Subsequently, these significant variables were optimized using the Box-Behnken design of response surface methodology. Ultimately, the optimized medium conditions were composed of sucrose 25.65 g·L-1, MgSO4·7H2O 1.24 g·L-1, and FeSO4·7H2O 3.36 g·L-1, and the yield of mycelial biomass reached 15.45 g·L-1, which represents an approximately 1.6-fold increase above the initial yield.

  19. Active Component Responsibility in Reserve Component Pre- and Postmobilization Training

    Science.gov (United States)

    2015-01-01

    President Lyndon Johnson refused to mobi- lize the RCs (MacCarley, 2012, pp. 38–39). 8 Active Component Responsibility in Reserve Component...ARFORGENwhitePaper1aug2011v3g2g.pdf Pernin, Christopher G., Dwayne M. Butler, Louay Constant, Lily Geyer, Duncan Long, Dan Madden, John E. Peters, James D. Powers

  20. Surface modification of tribological components in transportation

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R.

    1992-11-01

    This paper reviews a number of programs funded through the Engineered Tribological Interfaces (ETI) Task area of the Tribology Program that utilize energetic beams of atoms to enhance the mechanical and microstructural properties of near-surface regions to improve the tribological performance of critical components. The processes used in these programs include techniques based on chemical vapor deposition, physical vapor deposition, and ion implantation. A common feature of these techniques is their ability to produce dense and adherent modified surfaces without need for subsequent grinding/polishing treatments. Another feature of these techniques is their ability to introduce a wide range of elements into near-surface regions.

  1. Responsive acoustic surfaces

    DEFF Research Database (Denmark)

    Peters, Brady; Tamke, Martin; Nielsen, Stig Anton

    2011-01-01

    Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design...... for the acoustic conditions of these spaces. This paper describes an experimental research project that studied the design processes necessary to design for sound. A responsive acoustic surface was designed, fabricated and tested. This acoustic surface was designed to create specific sonic effects. The design...... was simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

  2. Adaptive Response Surface Techniques in Reliability Estimation

    DEFF Research Database (Denmark)

    Enevoldsen, I.; Faber, M. H.; Sørensen, John Dalsgaard

    1993-01-01

    Problems in connection with estimation of the reliability of a component modelled by a limit state function including noise or first order discontinuitics are considered. A gradient free adaptive response surface algorithm is developed. The algorithm applies second order polynomial surfaces...

  3. Emotional responses as independent components in EEG

    DEFF Research Database (Denmark)

    Jensen, Camilla Birgitte Falk; Petersen, Michael Kai; Larsen, Jakob Eg

    2014-01-01

    Combine wireless neuroheadsets with smartphones that enable mobile brain imaging can potentially allow us to design cognitive interfaces which adapt to our affective responses. Neuroimaging experiments using electroencephalography (EEG) initially identified two components elicited by pleasant...... or unpleasant images; early posterior negativity (EPN) and late positive potential (LPP). Recent studies suggest that several time course components may be modulated by emotional content in images or text. However these neural signatures are characterized by small voltage changes that would be highly...... susceptible to noise if captured in a mobile context. Hypothesizing that retrieval of emotional responses in mobile usage scenarios could be enhanced through spatial filtering, we compare a standard EEG electrode based analysis against an approach based on independent component analysis (ICA). By clustering...

  4. Modifing the Surface Layers of Mechanical Components

    Directory of Open Access Journals (Sweden)

    K. Slanec

    2003-01-01

    Full Text Available This paper deals with the creation of thin surface layers prepared by the Plasma Assisted Chemical Vapour Deposition Method (PACVD. Polished sample surfaces made of tool steel were used. An investigation of the dependence of layer thickness on process duration was carried out. The structure of the original surface and the structure of the coated surface were evaluated and compared. The microhardness of the surface areas was also measured.

  5. Responsive acoustic surfaces

    DEFF Research Database (Denmark)

    Peters, Brady; Tamke, Martin; Nielsen, Stig Anton

    2011-01-01

    Acoustic performance is defined by the parameter of reverberation time; however, this does not capture the acoustic experience in some types of open plan spaces. As many working and learning activities now take place in open plan spaces, it is important to be able to understand and design...... was simulated using custom integrated acoustic software and also using Odeon acoustic analysis software. The research demonstrates a method for designing space- and sound-defining surfaces, defines the concept of acoustic subspace, and suggests some new parameters for defining acoustic subspaces....

  6. Investigating the Complex Conductivity Response of Different Biofilm Components

    Science.gov (United States)

    Atekwana, E. A.; Abdel Aal, G. Z.; Sarkisova, S. A.; Patrauchan, M.

    2013-12-01

    Microbial biofilms are structured communities of microorganisms commonly attached to a surface and embedded in a self-produced matrix. The matrix is composed of extracellular polymeric substances (EPS), which commonly include extracellular DNA, proteins, and polysaccharides. In addition, the biofilm structure may contain some other components such as metabolic byproducts and biogenic nanoparticle minerals. Biogeophysical studies have demonstrated the sensitivity of spectral induced polarization (SIP) measurements to the growth and development of biofilm in saturated porous media. However, the mechanisms are not very well understood. The overarching goal of this study is to determine the contribution of the different biofilm components to the spectral induced polarization (SIP) signatures in aqueous and/or porous media. We investigated the SIP response of different biofilm components including bacterial cells, alginate (exopolysaccharide), phenazine (redox-active metabolite) and magnetite (semi-conductive particulate matter). The porous media was glass beads with grain diameter of 1 mm. Each of the biofilm components was suspended in a low salt growth medium with electrolytic conductivity of 513 μS/cm. Using Pseudomonas aeruginosa PAO1 cells in suspension and in porous media, we observed the increase in SIP parameters with increasing cell density with a very well defined relaxation peak at a frequency of ~10 Hz, which was predicted by recently developed quantitative models. However, this characteristic relaxation peak was minimized in the presence of porous media. We also observed that cells suspended in alginate enhance the polarization and show a peak frequency at ~10 Hz. The study of alginate gelation in liquid phase and porous media in vitro revealed that solidified (gelated) alginate (from brown algae) increased the magnitude of imaginary conductivity while real conductivity increased very moderately. In contrast, the study of the SIP response within a porous

  7. Mathematical and computer modeling of component surface shaping

    Science.gov (United States)

    Lyashkov, A.

    2016-04-01

    The process of shaping technical surfaces is an interaction of a tool (a shape element) and a component (a formable element or a workpiece) in their relative movements. It was established that the main objects of formation are: 1) a discriminant of a surfaces family, formed by the movement of the shape element relatively the workpiece; 2) an enveloping model of the real component surface obtained after machining, including transition curves and undercut lines; 3) The model of cut-off layers obtained in the process of shaping. When modeling shaping objects there are a lot of insufficiently solved or unsolved issues that make up a single scientific problem - a problem of qualitative shaping of the surface of the tool and then the component surface produced by this tool. The improvement of known metal-cutting tools, intensive development of systems of their computer-aided design requires further improvement of the methods of shaping the mating surfaces. In this regard, an important role is played by the study of the processes of shaping of technical surfaces with the use of the positive aspects of analytical and numerical mathematical methods and techniques associated with the use of mathematical and computer modeling. The author of the paper has posed and has solved the problem of development of mathematical, geometric and algorithmic support of computer-aided design of cutting tools based on computer simulation of the shaping process of surfaces.

  8. Surfaces: processing, coating, decontamination, pollution, etc. Surface mastering to prevent component corrosion

    International Nuclear Information System (INIS)

    Foucault, M.

    2012-01-01

    In the primary and secondary circuits of nuclear Pressurized Water Reactors, AREVA uses several nickel-based alloys or austenitic stainless steels for the manufacture of safety components. The experience feedback of the last twenty years allows us to point out the major role hold by the component surface state in their life duration. In this paper, we present four examples of problem encountered and solved by a surface study and the definition and implementation of processes for the surface control of the repaired components. Then, we propose some ideas about the present needs in term of analysis means to improve the surface knowledge and control of the manufactured components. (author)

  9. Hormonal component of tumor photodynamic therapy response

    Science.gov (United States)

    Korbelik, Mladen; Merchant, Soroush

    2008-02-01

    The involvement of adrenal glucocorticoid hormones in the response of the treatment of solid tumors by photodynamic therapy (PDT) comes from the induction of acute phase response by this modality. This adrenal gland activity is orchestrated through the engagement of the hypothalamic-pituitary-adrenal hormonal axis incited by stress signals emanating from the PDT-treated tumor. Glucocorticoid hormone activity engendered within the context of PDT-induced acute phase response performs multiple important functions; among other involvements they beget acute phase reactant production, systemic neutrophil mobilization, and control the production of inflammation-modulating and immunoregulatory proteins.

  10. Principal Component Surface (2011) for Fish Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.3x0.3 meter principal component analysis (PCA) surface for areas inside Fish Bay, St. John in the U.S. Virgin Islands (USVI). It was...

  11. Early micromovement of the Articular Surface Replacement (ASR) femoral component

    DEFF Research Database (Denmark)

    Penny, J O; Ding, M; Varmarken, J E

    2012-01-01

    Radiostereometric analysis (RSA) can detect early micromovement in unstable implant designs which are likely subsequently to have a high failure rate. In 2010, the Articular Surface Replacement (ASR) was withdrawn because of a high failure rate. In 19 ASR femoral components, the mean micromovement...

  12. Principal Component Surface (2011) for Coral Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.3x0.3 meter principal component analysis (PCA) surface for areas inside Coral Bay, St. John in the U.S. Virgin Islands (USVI). It was...

  13. Autonomous Aerobraking Using Thermal Response Surface Analysis

    Science.gov (United States)

    Prince, Jill L.; Dec, John A.; Tolson, Robert H.

    2007-01-01

    Aerobraking is a proven method of significantly increasing the science payload that can be placed into low Mars orbits when compared to an all propulsive capture. However, the aerobraking phase is long and has mission cost and risk implications. The main cost benefit is that aerobraking permits the use of a smaller and cheaper launch vehicle, but additional operational costs are incurred during the long aerobraking phase. Risk is increased due to the repeated thermal loading of spacecraft components and the multiple attitude and propulsive maneuvers required for successful aerobraking. Both the cost and risk burdens can be significantly reduced by automating the aerobraking operations phase. All of the previous Mars orbiter missions that have utilized aerobraking have increasingly relied on onboard calculations during aerobraking. Even though the temperature of spacecraft components has been the limiting factor, operational methods have relied on using a surrogate variable for mission control. This paper describes several methods, based directly on spacecraft component maximum temperature, for autonomously predicting the subsequent aerobraking orbits and prescribing apoapsis propulsive maneuvers to maintain the spacecraft within specified temperature limits. Specifically, this paper describes the use of thermal response surface analysis in predicting the temperature of the spacecraft components and the corresponding uncertainty in this temperature prediction.

  14. Non-conventional laser surface hardening for axisymmetric components

    Science.gov (United States)

    Liverani, Erica; Battiato, Nadine; Ascari, Alessandro; Fortunato, Alessandro

    2014-02-01

    A new process, based on ring spot geometry, is presented for laser surface hardening of large cylindrical com-ponents. The proposed technique leads to a very hard, deep and uniform treated area along the entire work piece surface without introducing a tempered zone, making the process very attractive compared to conventional induction hardening that exhibits both low energy efficiency and poor flexibility. A complete physical model is presented for the process, together with a study of the influence of process parameters on the final outcome. The results of an extensive validation campaign, carried out following the AISI1040 standard, are also reported.

  15. The Martian Dust Cycle: Investigation of the Surface Lifting Component

    Science.gov (United States)

    Murphy, James R.; Bridger, Alison F. C.; Haberle, Robert M.

    1996-01-01

    We have investigated the nature of the annual cycle of suspended dust in the martian atmosphere. This has been undertaken to understand the dynamical processes responsible for lifting dust from the surface, locations where dust is preferentially lifted, and preferred sites for dust deposition upon the surface. Our efforts have involved carrying out a number of numerical simulations with the Ames Mars General Circulation Model (GCM) interactively coupled with an aerosol transport/ micro-physical model. The model generates an annual dust cycle similar to that observed. Various feedbacks are present in the atmosphere/ surface system which enter into the generation of the cycle. Several locations are primary surface sources of dust, while much of the remaining planet's surface acts a sink for suspended dust.

  16. Surface composition of biomedical components by ion beam analysis

    International Nuclear Information System (INIS)

    Kenny, M.J.; Wielunski, L.S.; Baxter, G.R.

    1991-01-01

    Materials used for replacement body parts must satisfy a number of requirements such as biocompatibility and mechanical ability to handle the task with regard to strength, wear and durability. When using a CVD coated carbon fibre reinforced carbon ball, the surface must be ion implanted with uniform dose of nitrogen ions in order to make it wear resistant. The mechanism by which the wear resistance is improved is one of radiation damage and the required dose of about 10 16 cm -2 can have a tolerance of about 20%. To implant a spherical surface requires manipulation of the sample within the beam and control system (either computer or manually operated) to enable uniform dose all the way from polar to equatorial regions on the surface. A manipulator has been designed and built for this purpose. In order to establish whether the dose is uniform, nuclear reaction analysis using the reaction 14 N(d,α) 12 C is an ideal method of profiling. By taking measurements at a number of points on the surface, the uniformity of nitrogen dose can be ascertained. It is concluded that both Rutherford Backscattering and Nuclear Reaction Analysis can be used for rapid analysis of surface composition of carbon based materials used for replacement body components. 2 refs., 2 figs

  17. Surface temperature measurement of plasma facing components in tokamaks

    International Nuclear Information System (INIS)

    Amiel, Stephane

    2014-01-01

    During this PhD, the challenges on the non-intrusive surface temperature measurements of metallic plasma facing components in tokamaks are reported. Indeed, a precise material emissivity value is needed for classical infrared methods and the environment contribution has to be known particularly for low emissivities materials. Although methods have been developed to overcome these issues, they have been implemented solely for dedicated experiments. In any case, none of these methods are suitable for surface temperature measurement in tokamaks.The active pyrometry introduced in this study allows surface temperature measurements independently of reflected flux and emissivities using pulsed and modulated photothermal effect. This method has been validated in laboratory on metallic materials with reflected fluxes for pulsed and modulated modes. This experimental validation is coupled with a surface temperature variation induced by photothermal effect and temporal signal evolvement modelling in order to optimize both the heating source characteristics and the data acquisition and treatment. The experimental results have been used to determine the application range in temperature and detection wavelengths. In this context, the design of an active pyrometry system on tokamak has been completed, based on a bicolor camera for a thermography application in metallic (or low emissivity) environment.The active pyrometry method introduced in this study is a complementary technique of classical infrared methods used for thermography in tokamak environment which allows performing local and 2D surface temperature measurements independently of reflected fluxes and emissivities. (author) [fr

  18. Fine and coarse components in surface sediments from Bikini Lagoon

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V. E., LLNL

    1997-01-01

    In 1979, 21 years after the moratorium on nuclear testing in the Marshall Islands, surface sediment samples (to depths of 2 and 4 cm) were collected from 87 locations in the lagoon of Bikini Atoll, one of the two sites in the Marshall Islands used by the United States to test nuclear devices from 1946 through 1958. The main purpose for the collections was to map the distribution of long-lived man-made radionuclides associated with the bottom material. In addition the samples were processed to estimate the fraction of fine and coarse components to show, by comparison, what modifications occurred in the composition since the sediments were first described in samples collected before testing in 1946. Nuclear testing produced more finely divided material that is now found in the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. The 5 cratering events alone at Bikini Atoll redistributed sufficient material to account for the higher inventory of fine material found over the surface 4 cm of the sediment of the lagoon. Although the fraction of fine material in the bottom sediments was altered by the nuclear events, the combined processes of formation, transport and deposition were not sufficiently dynamic to greatly change the general geographical features of the major sedimentary components over most of the lagoon floor.

  19. Quantitative measurement of in-plane acoustic field components using surface-mounted fiber sensors

    Science.gov (United States)

    Claus, Richard O.; Dhawan, Rajat R.; Gunther, Michael F.; Murphy, Kent A.

    1993-01-01

    Extrinsic Fabry-Perot interferometric sensors have been used to obtain calibrated, quantitative measurements of the in-plane displacement components associated with the propagation of ultrasonic elastic stress waves on the surfaces of solids. The frequency response of the sensor is determined by the internal spacing between the two reflecting fiber endface surfaces which form the Fabry-Perot cavity, a distance which is easily controlled during fabrication. With knowledge of the material properties of the solid, the out-of-plane displacement component of the wave may also be determined, giving full field data.

  20. Bioadhesion to model thermally responsive surfaces

    Science.gov (United States)

    Andrzejewski, Brett Paul

    This dissertation focuses on the characterization of two surfaces: mixed self-assembled monolayers (SAMs) of hexa(ethylene glycol) and alkyl thiolates (mixed SAM) and poly(N-isopropylacrylamide) (PNIPAAm). The synthesis of hexa(ethylene gylcol) alkyl thiol (C11EG 6OH) is presented along with the mass spectrometry and nuclear magnetic resonance results. The gold substrates were imaged prior to SAM formation with atomic force micrscopy (AFM). Average surface roughness of the gold substrate was 0.44 nm, 0.67 nm, 1.65 nm for 15, 25 and 60 nm gold thickness, respectively. The height of the mixed SAM was measured by ellipsometry and varied from 13 to 28°A depending on surface mole fraction of C11EG6OH. The surface mole fraction of C11EG6OH for the mixed SAM was determined by X-ray photoelectron spectroscopy (XPS) with optimal thermal responsive behavior in the range of 0.4 to 0.6. The mixed SAM surface was confirmed to be thermally responsive by contact angle goniometry, 35° at 28°C and ˜55° at 40°C. In addition, the mixed SAM surfaces were confirmed to be thermally responsive for various aqueous mediums by tensiometry. Factors such as oxygen, age, and surface mole fraction and how they affect the thermal responsive of the mixed SAM are discussed. Lastly, rat fibroblasts were grown on the mixed SAM and imaged by phase contrast microscopy to show inhibition of attachment at temperatures below the molecular transition. Qualitative and quantitative measurements of the fibroblast adhesion data are provided that support the hypothesis of the mixed SAM exhibits a dominantly non-fouling molecular conformation at 25°C whereas it exhibits a dominantly fouling molecular conformation at 40°C. The adhesion of six model proteins: bovine serum albumin, collagen, pyruvate kinase, cholera toxin subunit B, ribonuclease, and lysozyme to the model thermally responsive mixed SAM were examined using AFM. All six proteins possessed adhesion to the pure component alkyl thiol, in

  1. Heavy components coupling effect on building response spectra generation

    International Nuclear Information System (INIS)

    Liu, T.H.; Johnson, E.R.

    1985-01-01

    This study investigates the dynamic coupling effect on the floor response spectra between the heavy components and the Reactor Interior (R/I) building in a PWR. The following cases were studied: (I) simplified models of one and two lump mass models representing building and heavy components, and (II) actual plant building and heavy component models. Response spectra are developed at building nodes for all models, using time-history analysis methods. Comparisons of response spectra from various models are made to observe the coupling effects. In some cases, this study found that the coupling would reduce the response spectra values in certain frequency regions even if the coupling is not required according to the above criteria. (orig./HP)

  2. Analysis of shape correctness of surfaces of diamond burnished components

    Directory of Open Access Journals (Sweden)

    Varga Gyula

    2017-01-01

    Full Text Available In these days, diamond burnishing is frequently used for final finishing manufacturing operations of components. Diamond burnishing belongs to cold plastic manufacturing procedures. When using this technique, the following advantages can be obtained: micro-hardness of near surface layer is increasing; surface roughness is improving and the shape correctness is also improving. This paper deals with how the different technological parameters of burnishing, such as the feed rate, the burnishing speed and the burnishing force effect on the cylindricity of the burnished workpiece. The experiment was done on some specimen having outer cylindrical surfaces. The experiments were executed by the Taguchi type Full Factorial Experiment Design method with which empirical formulas can be efficiently created. The measurements of the cylindricity of specimens were done with a circular and position error measuring. From the measured data, special improvement ratios were calculated in order to define the appropriate range of technological parameters which results high improvements. Further aim was to compare the measured values of different cylindricity parameters.

  3. Generalized Response Surface Methodology : A New Metaheuristic

    NARCIS (Netherlands)

    Kleijnen, J.P.C.

    2006-01-01

    Generalized Response Surface Methodology (GRSM) is a novel general-purpose metaheuristic based on Box and Wilson.s Response Surface Methodology (RSM).Both GRSM and RSM estimate local gradients to search for the optimal solution.These gradients use local first-order polynomials.GRSM, however, uses

  4. Soil Structure - A Neglected Component of Land-Surface Models

    Science.gov (United States)

    Fatichi, S.; Or, D.; Walko, R. L.; Vereecken, H.; Kollet, S. J.; Young, M.; Ghezzehei, T. A.; Hengl, T.; Agam, N.; Avissar, R.

    2017-12-01

    Soil structure is largely absent in most standard sampling and measurements and in the subsequent parameterization of soil hydraulic properties deduced from soil maps and used in Earth System Models. The apparent omission propagates into the pedotransfer functions that deduce parameters of soil hydraulic properties primarily from soil textural information. Such simple parameterization is an essential ingredient in the practical application of any land surface model. Despite the critical role of soil structure (biopores formed by decaying roots, aggregates, etc.) in defining soil hydraulic functions, only a few studies have attempted to incorporate soil structure into models. They mostly looked at the effects on preferential flow and solute transport pathways at the soil profile scale; yet, the role of soil structure in mediating large-scale fluxes remains understudied. Here, we focus on rectifying this gap and demonstrating potential impacts on surface and subsurface fluxes and system wide eco-hydrologic responses. The study proposes a systematic way for correcting the soil water retention and hydraulic conductivity functions—accounting for soil-structure—with major implications for near saturated hydraulic conductivity. Modification to the basic soil hydraulic parameterization is assumed as a function of biological activity summarized by Gross Primary Production. A land-surface model with dynamic vegetation is used to carry out numerical simulations with and without the role of soil-structure for 20 locations characterized by different climates and biomes across the globe. Including soil structure affects considerably the partition between infiltration and runoff and consequently leakage at the base of the soil profile (recharge). In several locations characterized by wet climates, a few hundreds of mm per year of surface runoff become deep-recharge accounting for soil-structure. Changes in energy fluxes, total evapotranspiration and vegetation productivity

  5. Application of response surface methodology for determining cutting ...

    Indian Academy of Sciences (India)

    by software Minitab (multiple linear regression and response surface methodology) in order to express the influence degree of the main cutting variables such as cutting speed, feed rate and depth of cut on cutting force components. These models would be helpful in selecting cutting variables for optimization of hard cutting ...

  6. Response Predicting LTCC Firing Shrinkage: A Response Surface Analysis Study

    Energy Technology Data Exchange (ETDEWEB)

    Girardi, Michael; Barner, Gregg; Lopez, Cristie; Duncan, Brent; Zawicki, Larry

    2009-02-25

    The Low Temperature Cofired Ceramic (LTCC) technology is used in a variety of applications including military/space electronics, wireless communication, MEMS, medical and automotive electronics. The use of LTCC is growing due to the low cost of investment, short development time, good electrical and mechanical properties, high reliability, and flexibility in design integration (3 dimensional (3D) microstructures with cavities are possible)). The dimensional accuracy of the resulting x/y shrinkage of LTCC substrates is responsible for component assembly problems with the tolerance effect that increases in relation to the substrate size. Response Surface Analysis was used to predict product shrinkage based on specific process inputs (metal loading, layer count, lamination pressure, and tape thickness) with the ultimate goal to optimize manufacturing outputs (NC files, stencils, and screens) in achieving the final product design the first time. Three (3) regression models were developed for the DuPont 951 tape system with DuPont 5734 gold metallization based on green tape thickness.

  7. Surfaces: processing, coating, decontamination, pollution, etc. Surface mastering to prevent component corrosion; Surfaces: traitement, revetements, decontamination, pollution, etc. Maitrise de la surface pour prevenir la corrosion des composants

    Energy Technology Data Exchange (ETDEWEB)

    Foucault, M. [Departement Corrosion Chimie, AREVA Centre Technique, BP 181, 71205 Le Creusot (France)

    2012-07-01

    In the primary and secondary circuits of nuclear Pressurized Water Reactors, AREVA uses several nickel-based alloys or austenitic stainless steels for the manufacture of safety components. The experience feedback of the last twenty years allows us to point out the major role hold by the component surface state in their life duration. In this paper, we present four examples of problem encountered and solved by a surface study and the definition and implementation of processes for the surface control of the repaired components. Then, we propose some ideas about the present needs in term of analysis means to improve the surface knowledge and control of the manufactured components. (author)

  8. Testing of Liquid Metal Components for Nuclear Surface Power Systems

    Science.gov (United States)

    Polzin, K. A.; Pearson, J. B.; Godfroy, T. J.; Schoenfeld, M.; Webster, K.; Briggs, M. H.; Geng, S. M.; Adkins, H. E.; Werner, J. E.

    2010-01-01

    The capability to perform testing at both the module/component level and in near prototypic reactor configurations using a non-nuclear test methodology allowed for evaluation of two components critical to the development of a potential nuclear fission power system for the lunar surface. A pair of 1 kW Stirling power convertors, similar to the type that would be used in a reactor system to convert heat to electricity, were integrated into a reactor simulator system to determine their performance using pumped NaK as the hot side working fluid. The performance in the pumped-NaK system met or exceed the baseline performance measurements where the converters were electrically heated. At the maximum hot-side temperature of 550 C the maximum output power was 2375 watts. A specially-designed test apparatus was fabricated and used to quantify the performance of an annular linear induction pump that is similar to the type that could be used to circulate liquid metal through the core of a space reactor system. The errors on the measurements were generally much smaller than the magnitude of the measurements, permitting accurate performance evaluation over a wide range of operating conditions. The pump produced flow rates spanning roughly 0.16 to 5.7 l/s (2.5 to 90 GPM), and delta p levels from less than 1 kPa to 90 kPa (greater than 0.145 psi to roughly 13 psi). At the nominal FSP system operating temperature of 525 C the maximum efficiency was just over 4%.

  9. Studies on yield and yield component responses of Mucuna ...

    African Journals Online (AJOL)

    Mucuna flagellipes was subjected to field scale culture over 1999 and 2000 growth seasons. Yield and yield component responses were evaluated using 4 x 3 factorial treatment combinations of phosphorus at 0, 20, 40, and 60kg P ha-1 and lime at 0, 1 and 2 t CaCO3 ha-1. The experiment was laid out in a randomized ...

  10. Linear response at the 4-component relativistic level

    DEFF Research Database (Denmark)

    Saue, T.; Jensen, Hans Jørgen Aagaard

    2003-01-01

    The theory, implementation, and application of linear response at the 4-component relativistic closed-shell Hartree-Fock level based on the concept of quasienergy and time averaging are reported. As such, an efficient AO-driven algorithm is obtained by assigning specific Hermiticity and time...

  11. Response surface use in safety analyses

    International Nuclear Information System (INIS)

    Prosek, A.

    1999-01-01

    When thousands of complex computer code runs related to nuclear safety are needed for statistical analysis, the response surface is used to replace the computer code. The main purpose of the study was to develop and demonstrate a tool called optimal statistical estimator (OSE) intended for response surface generation of complex and non-linear phenomena. The performance of optimal statistical estimator was tested by the results of 59 different RELAP5/MOD3.2 code calculations of the small-break loss-of-coolant accident in a two loop pressurized water reactor. The results showed that OSE adequately predicted the response surface for the peak cladding temperature. Some good characteristic of the OSE like monotonic function between two neighbor points and independence on the number of output parameters suggest that OSE can be used for response surface generation of any safety or system parameter in the thermal-hydraulic safety analyses.(author)

  12. Applications of response surface methodology approach to ...

    African Journals Online (AJOL)

    Applications of response surface methodology approach to determine the effect of temperature, time of incubation and light conditions on germination and germ tube growth of Puccinia coronata f.sp. avenae urediosopores.

  13. Response Surface Modeling Using Multivariate Orthogonal Functions

    Science.gov (United States)

    Morelli, Eugene A.; DeLoach, Richard

    2001-01-01

    A nonlinear modeling technique was used to characterize response surfaces for non-dimensional longitudinal aerodynamic force and moment coefficients, based on wind tunnel data from a commercial jet transport model. Data were collected using two experimental procedures - one based on modem design of experiments (MDOE), and one using a classical one factor at a time (OFAT) approach. The nonlinear modeling technique used multivariate orthogonal functions generated from the independent variable data as modeling functions in a least squares context to characterize the response surfaces. Model terms were selected automatically using a prediction error metric. Prediction error bounds computed from the modeling data alone were found to be- a good measure of actual prediction error for prediction points within the inference space. Root-mean-square model fit error and prediction error were less than 4 percent of the mean response value in all cases. Efficacy and prediction performance of the response surface models identified from both MDOE and OFAT experiments were investigated.

  14. Non-equilibrium Thermodynamic Dissolution Theory for Multi-Component Solid/Liquid Surfaces Involving Surface Adsorption and Radiolysis Kinetics

    International Nuclear Information System (INIS)

    Stout, R B

    2001-01-01

    A theoretical expression is developed for the dissolution rate response for multi-component radioactive materials that have surface adsorption kinetics and radiolysis kinetics when wetted by a multi-component aqueous solution. An application for this type of dissolution response is the performance evaluation of multi-component spent nuclear fuels (SNFs) for long term interim storage and for geological disposition. Typically, SNF compositions depend on initial composition, uranium oxide and metal alloys being most common, and on reactor burnup which results in a wide range of fission product and actinide concentrations that decay by alpha, beta, and gamma radiation. These compositional/burnup ranges of SNFs, whether placed in interim storage or emplaced in a geologic repository, will potentially be wetted by multi-component aqueous solutions, and these solutions may be further altered by radiolytic aqueous species due to three radiation fields. The solid states of the SNFs are not thermodynamically stable when wetted and will dissolve, with or without radiolysis. The following development of a dissolution theory is based on a non-equilibrium thermodynamic analysis of energy reactions and energy transport across a solid-liquid phase change discontinuity that propagates at a quasi-steady, dissolution velocity. The integral form of the energy balance equation is used for this spatial surface discontinuity analysis. The integral formulation contains internal energy functional of classical thermodynamics for both the SNFs' solid state and surface adsorption species, and the adjacent liquid state, which includes radiolytic chemical species. The steady-state concentrations of radiolytic chemical species are expressed by an approximate analysis of the decay radiation transport equation. For purposes of illustration a modified Temkin adsorption isotherm was assumed for the surface adsorption kinetics on an arbitrary, finite area of the solid-liquid dissolution interface. For

  15. Corrugated metal surface with pillars for terahertz surface plasmon polariton waveguide components

    KAUST Repository

    Yuehong, Xu

    2018-01-12

    In the terahertz regime, due to perfect conductivity of most metals, it is hard to realize a strong confinement of Surface plasmon polaritons (SPPs) although a propagation loss could be sufficiently low. We experimentally demonstrated a structure with periodic pillars arranged on a thin metal surface that supports bound modes of spoof SPPs at terahertz (THz) frequencies. By using scanning near-field THz microscopy, the electric field distribution above the metal surface within a distance of 130 μm was mapped. The results proved that this structure could guide spoof SPPs propagating along subwavelength waveguides, and at the same time reduce field expansion into free space. Further, for the development of integrated optical circuits, several components including straight waveguide, S-bend, Y-splitter and directional couplers were designed and characterized by the same method. We believe that the waveguide components proposed here will pave a new way for the development of flexible, wideband and compact photonic circuits operating at THz frequencies.

  16. An Instrument for Inspecting Aspheric Optical Surfaces and Components Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This is a Phase I proposal to develop an extremely versatile optical inspection tool for determining the optical figure of aspheric optical components, such as test...

  17. Multi-component joint analysis of surface waves

    Czech Academy of Sciences Publication Activity Database

    Dal Moro, Giancarlo; Moura, R.M.M.; Moustafa, S.S.R.

    2015-01-01

    Roč. 119, AUG (2015), s. 128-138 ISSN 0926-9851 Institutional support: RVO:67985891 Keywords : surface waves * surface wave dispersion * seismic data acquisition * seismic data inversion * velocity spectrum Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.355, year: 2015

  18. Physical parameter optimization by Response Surface Methodology ...

    African Journals Online (AJOL)

    Response Surface Methodology (RSM) is an empirical technique involving the use of Design Expert software to derive a predictive model similar to regression analysis. This present study explains the significant application of RSM in optimization of lipase production by Aspergillus niger. The experimental validation of the ...

  19. A discrete surface growth model for two components

    International Nuclear Information System (INIS)

    El-Nashar, H.F.; Cerdeira, H.A.

    2000-04-01

    We present a ballistic deposition model for the surface growth of a binary species A and C. Numerical simulations of the growth kinetics show a deviation from the Kardar-Parisi-Zhang universality class, model valid for only one kind of deposited particles. The study also shows that when the deposition of particles with less active bonds occurs more frequently the voids under the surface become relevant. However, the increase in overhang/voids processes under the moving interface does not strengthen greatly the local surface gradient. (author)

  20. Study of Huizhou architecture component point cloud in surface reconstruction

    Science.gov (United States)

    Zhang, Runmei; Wang, Guangyin; Ma, Jixiang; Wu, Yulu; Zhang, Guangbin

    2017-06-01

    Surface reconfiguration softwares have many problems such as complicated operation on point cloud data, too many interaction definitions, and too stringent requirements for inputing data. Thus, it has not been widely popularized so far. This paper selects the unique Huizhou Architecture chuandou wooden beam framework as the research object, and presents a complete set of implementation in data acquisition from point, point cloud preprocessing and finally implemented surface reconstruction. Firstly, preprocessing the acquired point cloud data, including segmentation and filtering. Secondly, the surface’s normals are deduced directly from the point cloud dataset. Finally, the surface reconstruction is studied by using Greedy Projection Triangulation Algorithm. Comparing the reconstructed model with the three-dimensional surface reconstruction softwares, the results show that the proposed scheme is more smooth, time efficient and portable.

  1. Stress corrosion cracking of Ni-based alloys in PWR primary water. Component surface control

    International Nuclear Information System (INIS)

    Foucault, M.

    2004-01-01

    In the PWR plant primary circuit, FRAMATOME-ANP uses several nickel-base alloys or austenitic stainless steels for the manufacture of safety components. The experience feedback of the last twenty years allows us to point out the major role played by the surface state of the components in their life duration. In this paper, we present two examples of problems encountered and solved by a surface study and the definition and implementation of a process for the surface control of the repair components. Then, we propose some ideas about the present needs in terms of analysis methods to improve the surface knowledge and the control of the manufactured components. (author)

  2. Integrated Optical Components Utilizing Long-Range Surface Plasmon Polaritons

    DEFF Research Database (Denmark)

    Boltasseva, Alexandra; Nikolajsen, Thomas; Leosson, Kristjan

    2005-01-01

    New optical waveguide technology for integrated optics, based on propagation of long-range surface plasmon polaritons (LR-SPPs) along metal stripes embedded in dielectric, is presented. Guiding and routing of electromagnetic radiation along nanometer-thin and micrometer-wide gold stripes embedded...

  3. Laser-assisted surface cleaning of metallic components

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... Keywords. YAG laser, oxide layer, contamination, cleaning. Abstract. Removal of a thin oxide layer from a tungsten ribbon and ThO2 particulates from zircaloy surface was achieved using a pulsed Nd:YAG laser. The removal mechanism of the oxide layer from the tungsten ribbon was identified as spallation ...

  4. Laser-assisted surface cleaning of metallic components

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... 1Advanced Fuel Fabrication Facility, Bhabha Atomic Research Centre, Tarapur 401 504, India ... taining to nuclear industry in the field of nuclear fuel fabrication and radioactive waste management. As we know .... ThO2 powder taken along with a small quantity of isopropyl alcohol on the surface of. 240.

  5. Laser-assisted surface cleaning of metallic components

    Indian Academy of Sciences (India)

    2014-02-09

    Feb 9, 2014 ... for effective utilization of uranium and thorium reserves to fulfill the ever growing need of energy [3]. ... nism of laser-assisted removal of ThO2 particulates off the metal surface and present here results of some ... samples (tungsten ribbon, thoria-contaminated zircaloy metal) were irradiated inside a chamber ...

  6. Molecular clutch drives cell response to surface viscosity.

    Science.gov (United States)

    Bennett, Mark; Cantini, Marco; Reboud, Julien; Cooper, Jonathan M; Roca-Cusachs, Pere; Salmeron-Sanchez, Manuel

    2018-02-06

    Cell response to matrix rigidity has been explained by the mechanical properties of the actin-talin-integrin-fibronectin clutch. Here the molecular clutch model is extended to account for cell interactions with purely viscous surfaces (i.e., without an elastic component). Supported lipid bilayers present an idealized and controllable system through which to study this concept. Using lipids of different diffusion coefficients, the mobility (i.e., surface viscosity) of the presented ligands (in this case RGD) was altered by an order of magnitude. Cell size and cytoskeletal organization were proportional to viscosity. Furthermore, there was a higher number of focal adhesions and a higher phosphorylation of FAK on less-mobile (more-viscous) surfaces. Actin retrograde flow, an indicator of the force exerted on surfaces, was also seen to be faster on more mobile surfaces. This has consequential effects on downstream molecules; the mechanosensitive YAP protein localized to the nucleus more on less-mobile (more-viscous) surfaces and differentiation of myoblast cells was enhanced on higher viscosity. This behavior was explained within the framework of the molecular clutch model, with lower viscosity leading to a low force loading rate, preventing the exposure of mechanosensitive proteins, and with a higher viscosity causing a higher force loading rate exposing these sites, activating downstream pathways. Consequently, the understanding of how viscosity (regardless of matrix stiffness) influences cell response adds a further tool to engineer materials that control cell behavior. Copyright © 2018 the Author(s). Published by PNAS.

  7. Surface energy budget responses to radiative forcing at Summit, Greenland

    Science.gov (United States)

    Miller, Nathaniel B.; Shupe, Matthew D.; Cox, Christopher J.; Noone, David; Persson, P. Ola G.; Steffen, Konrad

    2017-02-01

    Greenland Ice Sheet surface temperatures are controlled by an exchange of energy at the surface, which includes radiative, turbulent, and ground heat fluxes. Data collected by multiple projects are leveraged to calculate all surface energy budget (SEB) terms at Summit, Greenland, for the full annual cycle from July 2013 to June 2014 and extend to longer periods for the radiative and turbulent SEB terms. Radiative fluxes are measured directly by a suite of broadband radiometers. Turbulent sensible heat flux is estimated via the bulk aerodynamic and eddy correlation methods, and the turbulent latent heat flux is calculated via a two-level approach using measurements at 10 and 2 m. The subsurface heat flux is calculated using a string of thermistors buried in the snow pack. Extensive quality-control data processing produced a data set in which all terms of the SEB are present 75 % of the full annual cycle, despite the harsh conditions. By including a storage term for a near-surface layer, the SEB is balanced in this data set to within the aggregated uncertainties for the individual terms. November and August case studies illustrate that surface radiative forcing is driven by synoptically forced cloud characteristics, especially by low-level, liquid-bearing clouds. The annual cycle and seasonal diurnal cycles of all SEB components indicate that the non-radiative terms are anticorrelated to changes in the total radiative flux and are hence responding to cloud radiative forcing. Generally, the non-radiative SEB terms and the upwelling longwave radiation component compensate for changes in downwelling radiation, although exact partitioning of energy in the response terms varies with season and near-surface characteristics such as stability and moisture availability. Substantial surface warming from low-level clouds typically leads to a change from a very stable to a weakly stable near-surface regime with no solar radiation or from a weakly stable to neutral

  8. Electro-responsive polyelectrolyte-coated surfaces.

    Science.gov (United States)

    Sénéchal, V; Saadaoui, H; Rodriguez-Hernandez, J; Drummond, C

    2017-07-01

    The anchoring of polymer chains at solid surfaces is an efficient way to modify interfacial properties like the stability and rheology of colloidal dispersions, lubrication and biocompatibility. Polyelectrolytes are good candidates for the building of smart materials, as the polyion chain conformation can often be tuned by manipulation of different physico-chemical variables. However, achieving efficient and reversible control of this process represents an important technological challenge. In this regard, the application of an external electrical stimulus on polyelectrolytes seems to be a convenient control strategy, for several reasons. First, it is relatively easy to apply an electric field to the material with adequate spatiotemporal control. In addition, in contrast to chemically induced changes, the molecular response to a changing electric field occurs relatively quickly. If the system is properly designed, this response can then be used to control the magnitude of surface properties. In this work we discuss the effect of an external electric field on the adhesion and lubrication properties of several polyelectrolyte-coated surfaces. The influence of the applied field is investigated at different pH and salt conditions, as the polyelectrolyte conformation is sensitive to these variables. We show that it is possible to fine tune friction and adhesion using relatively low applied fields.

  9. Surface response model for quasielastic scattering

    International Nuclear Information System (INIS)

    Esbensen, H.

    1987-01-01

    The description of nucleon-nucleus inelastic scattering in terms of single-scattering has been very successful at intermediate energies. Nuclear structure is the most dominant feature at low excitations and forward scattering, and the Distorted Wave Impulse Approximation (DWIA) has been the most useful technique to extract structure information. The conventional DWIA has also been applied to quasielastic scattering. However, this method is very time-consuming at large scattering angles, since many different excitations of different multipolarities contribute to the inelastic cross section. It has therefore been useful to develop an approximate treatment that contains the main physics of quasielastic scattering. In the following the author will try to establish the connection between the DWIA and the much simpler Surface Response Model. The author will give a short description of the Random Phase Approximation that is used to calculate the nuclear response, and illustrate the spin-isospin dependence of the nucleon-nucleon t-matrix interaction, which is used to generate the excitations of the target nucleus. Finally, some of the applications of the surface response model to (p,p'), (p,n) and ( 3 H,t) reactions are reviewed. 19 refs., 5 figs

  10. Retention Forces between Titanium and Zirconia Components of Two-Part Implant Abutments with Different Techniques of Surface Modification.

    Science.gov (United States)

    von Maltzahn, Nadine Freifrau; Holstermann, Jan; Kohorst, Philipp

    2016-08-01

    The adhesive connection between titanium base and zirconia coping of two-part abutments may be responsible for the failure rate. A high mechanical stability between both components is essential for the long-term success. The aim of the present in-vitro study was to evaluate the influence of different surface modification techniques and resin-based luting agents on the retention forces between titanium and zirconia components in two-part implant abutments. A total of 120 abutments with a titanium base bonded to a zirconia coping were investigated. Two different resin-based luting agents (Panavia F 2.0 and RelyX Unicem) and six different surface modifications were used to fix these components, resulting in 12 test groups (n = 10). The surface of the test specimens was mechanically pretreated with aluminium oxide blasting in combination with application of two surface activating primers (Alloy Primer, Clearfil Ceramic Primer) or a tribological conditioning (Rocatec), respectively. All specimens underwent 10,000 thermal cycles between 5°C and 55°C in a moist environment. A pull-off test was then conducted to determine retention forces between the titanium and zirconia components, and statistical analysis was performed (two-way anova). Finally, fracture surfaces were analyzed by light and scanning electron microscopy. No significant differences were found between Panavia F 2.0 and RelyX Unicem. However, the retention forces were significantly influenced by the surface modification technique used (p zirconia copings were pretreated with aluminium oxide blasting, and with the application of Clearfil Ceramic Primer. Surface modification techniques crucially influence the retention forces between titanium and zirconia components in two-part implant abutments. All adhesion surfaces should be pretreated by sandblasting. Moreover, a phosphate-based primer serves to enhance long-term retention of the components. © 2015 Wiley Periodicals, Inc.

  11. Femtosecond tunneling response of surface plasmon polaritons

    DEFF Research Database (Denmark)

    Keil, Ulrich Dieter Felix; Ha, Taekjip; Jensen, Jacob Riis

    1998-01-01

    We obtain femtosecond (200 fs) time resolution using a scanning tunneling microscope on surface plasmon polaritons (SPPs) generated by two 100 fs laser beams in total internal reflection geometry. The tunneling gap dependence of the signal clearly indicates the tunneling origin of the signal...... and suggests that nanometer spatial resolution can be obtained together with femtosecond temporal resolution. This fast response, in contrast to the picosecond decay time of SPPs revealed by differential reflectivity measurements, can be attributed to a coherent superposition of SPPs rectified at the tunneling...... junction. (C) 1998 American Institute of Physics. [S0003-6951(98)02223-2]....

  12. Two-component injection moulding simulation of ABS-POM micro structured surfaces

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Islam, Aminul

    2013-01-01

    Multi-component micro injection moulding (μIM) processes such as two-component (2k) μIM are the key technologies for the mass fabrication of multi-material micro products. 2k-μIM experiments involving a miniaturized test component with micro features in the sub-mm dimensional range and moulding a...... process. Flow front predictions are compared with experimental results using the short shots technique over the whole miniaturized component and within the surface micro structures....

  13. Turbine component having surface cooling channels and method of forming same

    Science.gov (United States)

    Miranda, Carlos Miguel; Trimmer, Andrew Lee; Kottilingam, Srikanth Chandrudu

    2017-09-05

    A component for a turbine engine includes a substrate that includes a first surface, and an insert coupled to the substrate proximate the substrate first surface. The component also includes a channel. The channel is defined by a first channel wall formed in the substrate and a second channel wall formed by at least one coating disposed on the substrate first surface. The component further includes an inlet opening defined in flow communication with the channel. The inlet opening is defined by a first inlet wall formed in the substrate and a second inlet wall defined by the insert.

  14. Improvements to a Response Surface Thermal Model for Orion

    Science.gov (United States)

    Miller, Stephen W.; Walker, William Q.

    2011-01-01

    A study was performed to determine if a Design of Experiments (DOE)/Response Surface Methodology could be applied to on-orbit thermal analysis and produce a set of Response Surface Equations (RSE) that predict Orion vehicle temperatures within 10 F. The study used the Orion Outer Mold Line model. Five separate factors were identified for study: yaw, pitch, roll, beta angle, and the environmental parameters. Twenty-three external Orion components were selected and their minimum and maximum temperatures captured over a period of two orbits. Thus, there are 46 responses. A DOE case matrix of 145 runs was developed. The data from these cases were analyzed to produce a fifth order RSE for each of the temperature responses. For the 145 cases in the DOE matrix, the agreement between the engineering data and the RSE predictions was encouraging with 40 of the 46 RSEs predicting temperatures within the goal band. However, the verification cases showed most responses did not meet the 10 F goal. After reframing the focus of the study to better align the RSE development with the purposes of the model, a set of RSEs for both the minimum and maximum radiator temperatures was produced which predicted the engineering model output within +/-4 F. Therefore, with the correct application of the DOE/RSE methodology, RSEs can be developed that provide analysts a fast and easy way to screen large numbers of environments and assess proposed changes to the RSE factors.

  15. An atlas of monthly mean distributions of GEOSAT sea surface height, SSMI surface wind speed, AVHRR/2 sea surface temperature, and ECMWF surface wind components during 1988

    Science.gov (United States)

    Halpern, D.; Zlotnicki, V.; Newman, J.; Brown, O.; Wentz, F.

    1991-01-01

    Monthly mean global distributions for 1988 are presented with a common color scale and geographical map. Distributions are included for sea surface height variation estimated from GEOSAT; surface wind speed estimated from the Special Sensor Microwave Imager on the Defense Meteorological Satellite Program spacecraft; sea surface temperature estimated from the Advanced Very High Resolution Radiometer on NOAA spacecrafts; and the Cartesian components of the 10m height wind vector computed by the European Center for Medium Range Weather Forecasting. Charts of monthly mean value, sampling distribution, and standard deviation value are displayed. Annual mean distributions are displayed.

  16. Principal component analysis for surface reflection components and structure in facial images and synthesis of facial images for various ages

    Science.gov (United States)

    Hirose, Misa; Toyota, Saori; Ojima, Nobutoshi; Ogawa-Ochiai, Keiko; Tsumura, Norimichi

    2017-08-01

    In this paper, principal component analysis is applied to the distribution of pigmentation, surface reflectance, and landmarks in whole facial images to obtain feature values. The relationship between the obtained feature vectors and the age of the face is then estimated by multiple regression analysis so that facial images can be modulated for woman aged 10-70. In a previous study, we analyzed only the distribution of pigmentation, and the reproduced images appeared to be younger than the apparent age of the initial images. We believe that this happened because we did not modulate the facial structures and detailed surfaces, such as wrinkles. By considering landmarks and surface reflectance over the entire face, we were able to analyze the variation in the distributions of facial structures and fine asperity, and pigmentation. As a result, our method is able to appropriately modulate the appearance of a face so that it appears to be the correct age.

  17. Monthly version of HadISST sea surface temperature state-space components

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — State-Space Decomposition of Monthly version of HadISST sea surface temperature component (1-degree). See Rayner, N. A., Parker, D. E., Horton, E. B., Folland, C....

  18. Printing transferable components using microstructured elastomeric surfaces with pressure modulated reversible adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Menard, Etienne; Rogers, John A.; Kim, Seok; Carlson, Andrew

    2016-08-09

    In a method of printing a transferable component, a stamp including an elastomeric post having three-dimensional relief features protruding from a surface thereof is pressed against a component on a donor substrate with a first pressure that is sufficient to mechanically deform the relief features and a region of the post between the relief features to contact the component over a first contact area. The stamp is retracted from the donor substrate such that the component is adhered to the stamp. The stamp including the component adhered thereto is pressed against a receiving substrate with a second pressure that is less than the first pressure to contact the component over a second contact area that is smaller than the first contact area. The stamp is then retracted from the receiving substrate to delaminate the component from the stamp and print the component onto the receiving substrate. Related apparatus and stamps are also discussed.

  19. Multidisciplinary design optimization using response surface analysis

    Science.gov (United States)

    Unal, Resit

    1992-01-01

    Aerospace conceptual vehicle design is a complex process which involves multidisciplinary studies of configuration and technology options considering many parameters at many values. NASA Langley's Vehicle Analysis Branch (VAB) has detailed computerized analysis capabilities in most of the key disciplines required by advanced vehicle design. Given a configuration, the capability exists to quickly determine its performance and lifecycle cost. The next step in vehicle design is to determine the best settings of design parameters that optimize the performance characteristics. Typical approach to design optimization is experience based, trial and error variation of many parameters one at a time where possible combinations usually number in the thousands. However, this approach can either lead to a very long and expensive design process or to a premature termination of the design process due to budget and/or schedule pressures. Furthermore, one variable at a time approach can not account for the interactions that occur among parts of systems and among disciplines. As a result, vehicle design may be far from optimal. Advanced multidisciplinary design optimization (MDO) methods are needed to direct the search in an efficient and intelligent manner in order to drastically reduce the number of candidate designs to be evaluated. The payoffs in terms of enhanced performance and reduced cost are significant. A literature review yields two such advanced MDO methods used in aerospace design optimization; Taguchi methods and response surface methods. Taguchi methods provide a systematic and efficient method for design optimization for performance and cost. However, response surface method (RSM) leads to a better, more accurate exploration of the parameter space and to estimated optimum conditions with a small expenditure on experimental data. These two methods are described.

  20. Identifying apple surface defects using principal components analysis and artifical neural networks

    Science.gov (United States)

    Artificial neural networks and principal components were used to detect surface defects on apples in near-infrared images. Neural networks were trained and tested on sets of principal components derived from columns of pixels from images of apples acquired at two wavelengths (740 nm and 950 nm). I...

  1. Selection of a design for response surface

    Science.gov (United States)

    Ranade, Shruti Sunil; Thiagarajan, Padma

    2017-11-01

    Box-Behnken, Central-Composite, D and I-optimal designs were compared using statistical tools. Experimental trials for all designs were generated. Random uniform responses were simulated for all models. R-square, Akaike and Bayesian Information Criterion for the fitted models were noted. One-way ANOVA and Tukey’s multiple comparison test were performed on these parameters. These models were evaluated based on the number of experimental trials generated in addition to the results of the statistical analyses. D-optimal design generated 12 trials in its model, which was lesser in comparison to both Central Composite and Box-Behnken designs. The R-square values of the fitted models were found to possess a statistically significant difference (P<0.0001). D-optimal design not only had the highest mean R-square value (0.7231), but also possessed the lowest means for both Akaike and Bayesian Information Criterion. The D-optimal design was recommended for generation of response surfaces, based on the assessment of the above parameters.

  2. Seismic response of aboveground steel storage tanks: comparative study of analyses by six and three correlated earthquake components

    Directory of Open Access Journals (Sweden)

    Taher Ghazvini

    Full Text Available Ground motions at a point on the ground surface can be decomposed to six components, namely three translational components and three rotational components; translational components include two components in the horizontal plane, and one in the vertical direction. Rotation about horizontal axes leads to rising of rocking, while the rotational component about a vertical axis generates torsional effects even in symmetrical buildings. Due to evident and significant contribution of ground shakings to the overall response of structures, rocking and torsional components of these motions resulted by strong earthquakes are recently subjected to widespread researches by engineering and research communities. In this study, first rotational components of ground motion are determined using a method developed by Hong-Nan Li and et al (2004. This method is based on frequency dependence on the angle of incidence and the wave velocity. In consequence, aboveground steel storage tanks (ASSTs with different water elevations have been analyzed with the effects of these six components of earthquake. Three translational components of six important earthquakes have been adopted to generate relevant rotational components based on SV and SH wave incidence by the Fast Fourier Transform (FFT with the discrete frequencies of time histories of translational motion. Using finite element method, linear properties of tank material including steel for cylindrical tanks have been taken into with considering fluid-structure interaction. Numerical linear dynamic analysis of these structures considering six components of earthquake motions is presented; results are compared with cases in which three translational components are considered.

  3. The study on surface characteristics of high transmission components by 3D printing technique

    Science.gov (United States)

    Kuo, Hui-Jean; Huang, Chien-Yao; Wang, Wan-Hsuan; Lin, Ping-Hung; Tsay, Ho-Lin; Hsu, Wei-Yao

    2017-06-01

    3D printing is a high freedom fabrication technique. Any components, which designed by 3D design software or scanned from real parts, can be printed. The printing materials include metals, plastics and biocompatible materials etc. Especially for those high transmission components used in optical system or biomedical field can be printed, too. High transmission lens increases the performances of optical system. And high transmission cover or shell using in biomedical field helps observers to see the structures inside, such as brain, bone, and vessels. But the surface of printed components is not transparent, even the inside layer is transparent. If we increase the transmittance of surface, the components which fabricated by 3D printing process could have high transmission. In this paper, we using illuminating and polishing methods to improve the transmittance of printing surface. The illuminating time is the experiment parameters in illuminating method. The roughness and transmission of printing components are the evaluating targets. A 3D printing machine, Stratasys Connex 500, has been used to print high transmittance components in this paper. The surface transmittance of printing components is increasing above 80 % by polishing method.

  4. Switchable and responsive surfaces and materials for biomedical applications

    CERN Document Server

    Zhang, Johnathan

    2015-01-01

    Surface modification of biomaterials can ultimately determine whether a material is accepted or rejected from the human body, and a responsive surface can further make the material ""smart"" and ""intelligent"". Switchable and Responsive Surfaces and Materials for Biomedical Applications outlines synthetic and biological materials that are responsive under different stimuli, their surface design and modification techniques, and applicability in regenerative medicine/tissue engineering,  drug delivery, medical devices, and biomedical diagnostics. Part one provides a detailed overview of swit

  5. Peak earthquake response of structures under multi-component excitations

    Science.gov (United States)

    Song, Jianwei; Liang, Zach; Chu, Yi-Lun; Lee, George C.

    2007-12-01

    Accurate estimation of the peak seismic responses of structures is important in earthquake resistant design. The internal force distributions and the seismic responses of structures are quite complex, since ground motions are multi-directional. One key issue is the uncertainty of the incident angle between the directions of ground motion and the reference axes of the structure. Different assumed seismic incidences can result in different peak values within the scope of design spectrum analysis for a given structure and earthquake ground motion record combination. Using time history analysis to determine the maximum structural responses excited by a given earthquake record requires repetitive calculations to determine the critical incident angle. This paper presents a transformation approach for relatively accurate and rapid determination of the maximum peak responses of a linear structure subjected to three-dimensional excitations within all possible seismic incident angles. The responses can be deformations, internal forces, strains and so on. An irregular building structure model is established using SAP2000 program. Several typical earthquake records and an artificial white noise are applied to the structure model to illustrate the variation of the maximum structural responses for different incident angles. Numerical results show that for many structural parameters, the variation can be greater than 100%. This method can be directly applied to time history analysis of structures using existing computer software to determine the peak responses without carrying out the analyses for all possible incident angles. It can also be used to verify and/or modify aseismic designs by using response spectrum analysis.

  6. Adsorption-Driven Surface Segregation of the Less Reactive Alloy Component

    DEFF Research Database (Denmark)

    Andersson, Klas Jerker; Calle Vallejo, Federico; Rossmeisl, Jan

    2009-01-01

    Counterintuitive to expectations and all prior observations of adsorbate-induced surface segregation of the more reactive alloy component (the one forming the stronger bond with the adsorbate), we show that CO adsorption at elevated pressures and temperatures pulls the less reactive Cu to the sur......Counterintuitive to expectations and all prior observations of adsorbate-induced surface segregation of the more reactive alloy component (the one forming the stronger bond with the adsorbate), we show that CO adsorption at elevated pressures and temperatures pulls the less reactive Cu...... to the surface of a CuPt near-surface alloy. The Cu surface segregation is driven by the formation of a stable self-organized CO/CuPt surface alloy structure and is rationalized in terms of the radically stronger Pt−CO bond when Cu is present in the first surface layer of Pt. The results, which are expected...... to apply to a range of coinage (Cu, Ag)/Pt-group bimetallic surface alloys, open up new possibilities in selective and dynamical engineering of alloy surfaces for catalysis....

  7. Surface layer scintillometry for estimating the sensible heat flux component of the surface energy balance

    Directory of Open Access Journals (Sweden)

    M. J. Savage

    2010-01-01

    Full Text Available The relatively recently developed scintillometry method, with a focus on the dual-beam surface layer scintillometer (SLS, allows boundary layer atmospheric turbulence, surface sensible heat and momentum flux to be estimated in real-time. Much of the previous research using the scintillometer method has involved the large aperture scintillometer method, with only a few studies using the SLS method. The SLS method has been mainly used by agrometeorologists, hydrologists and micrometeorologists for atmospheric stability and surface energy balance studies to obtain estimates of sensible heat from which evaporation estimates representing areas of one hectare or larger are possible. Other applications include the use of the SLS method in obtaining crucial input parameters for atmospheric dispersion and turbulence models. The SLS method relies upon optical scintillation of a horizontal laser beam between transmitter and receiver for a separation distance typically between 50 and 250 m caused by refractive index inhomogeneities in the atmosphere that arise from turbulence fluctuations in air temperature and to a much lesser extent the fluctuations in water vapour pressure. Measurements of SLS beam transmission allow turbulence of the atmosphere to be determined, from which sub-hourly, real-time and in situ path-weighted fluxes of sensible heat and momentum may be calculated by application of the Monin-Obukhov similarity theory. Unlike the eddy covariance (EC method for which corrections for flow distortion and coordinate rotation are applied, no corrections to the SLS measurements, apart from a correction for water vapour pressure, are applied. Also, path-weighted SLS estimates over the propagation path are obtained. The SLS method also offers high temporal measurement resolution and usually greater spatial coverage compared to EC, Bowen ratio energy balance, surface renewal and other sensible heat measurement methods. Applying the shortened surface

  8. Personnel development as component of business social responsibility

    Directory of Open Access Journals (Sweden)

    Vlasova T.

    2013-06-01

    Full Text Available Essence of social responsibility of business has been determined in the article on the basis of existent scientific approaches. It has been educed that in the present conditions the entrepreneurship functions should be complemented by a social function. In a market economy entrepreneurial activity is indissolubly related to the concept of responsibility (to the country, society and partners. Nature of social investment has been substantiated in the article, the difference between charity and social investing carried out by the company through the implementation of internal and external social programs has been shown.

  9. Physiological responses to taste signals of functional food components.

    Science.gov (United States)

    Narukawa, Masataka

    2018-02-01

    The functions of food have three categories: nutrition, palatability, and bioregulation. As the onset of lifestyle-related diseases has increased, many people have shown interest in functional foods that are beneficial to bioregulation. We believe that functional foods should be highly palatable for increased acceptance from consumers. In order to design functional foods with a high palatability, we have investigated about the palatability, especially in relation to the taste of food. In this review, we discuss (1) the identification of taste receptors that respond to functional food components; (2) an analysis of the peripheral taste transduction system; and (3) the investigation of the relationship between physiological functions and taste signals.

  10. Friction surfacing for enhanced surface protection of marine engineering components: erosion-corrosion study

    Science.gov (United States)

    Rajakumar, S.; Balasubramanian, V.; Balakrishnan, M.

    2016-08-01

    Good mechanical properties combined with outstanding corrosion-resistance properties of cast nickel-aluminum bronze (NAB) alloy lead to be a specific material for many marine applications, including ship propellers. However, the erosion-corrosion resistance of cast-NAB alloy is not as good as wrought NAB alloy. Hence, in this investigation, an attempt has been made to improve the erosion-corrosion resistance of cast NAB alloy by depositing wrought (extruded) NAB alloy applying the friction surfacing (FS) technique. Erosion-corrosion tests were carried out in slurries composed of sand particles of 3.5% NaCl solution. Silica sand having a nominal size range of 250-355 μm is used as an erodent. Specimens were tested at 30° and 90° impingement angles. It is observed that the erosion and erosion-corrosion resistance of friction surfaced NAB alloy exhibited an improvement as compared to cast NAB alloy. Scanning electron microscope (SEM) analysis showed that the erosion tracks developed on the cast NAB alloy were wider and deeper than those formed on the friction surfaced extruded NAB alloy.

  11. Microclimatic models. Estimation of components of the energy balance over land surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Heikinheimo, M.; Venaelaeinen, A.; Tourula, T. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1996-12-31

    Climates at regional scale are strongly dependent on the interaction between atmosphere and its lower boundary, the oceans and the land surface mosaic. Land surfaces influence climate through their albedo, and the aerodynamic roughness, the processes of the biosphere and many soil hydrological properties; all these factors vary considerably geographically. Land surfaces receive a certain portion of the solar irradiance depending on the cloudiness, atmospheric transparency and surface albedo. Short-wave solar irradiance is the source of the heat energy exchange at the earth`s surface and also regulates many biological processes, e.g. photosynthesis. Methods for estimating solar irradiance, atmospheric transparency and surface albedo were reviewed during the course of this project. The solar energy at earth`s surface is consumed for heating the soil and the lower atmosphere. Where moisture is available, evaporation is one of the key components of the surface energy balance, because the conversion of liquid water into water vapour consumes heat. The evaporation process was studied by carrying out field experiments and testing parameterisation for a cultivated agricultural surface and for lakes. The micrometeorological study over lakes was carried out as part of the international `Northern Hemisphere Climatic Processes Experiment` (NOPEX/BAHC) in Sweden. These studies have been aimed at a better understanding of the energy exchange processes of the earth`s surface-atmosphere boundary for a more accurate and realistic parameterisation of the land surface in atmospheric models

  12. Principal Component Surface (2011) for St. Thomas East End Reserve, St. Thomas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.3x0.3 meter principal component analysis (PCA) surface for areas the St. Thomas East End Reserve (STEER) in the U.S. Virgin Islands (USVI)....

  13. [Studies on the interaction of blood components with ultra-smooth polymer surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, T.H. [New Mexico Univ., Albuquerque, NM (United States). School of Medicine

    1989-04-17

    This report is in three parts, though each is briefly described data is provided. The three parts address (1) radioiodination of human thrombin and fibrinogen; (2) interaction of blood components with ultra- smooth polymer surfaces; and (3) initial studies of Tecoflex and treated Tecoflex cups with normal serum samples.

  14. Two-component injection moulding simulation of ABS-POM micro structured surfaces

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Islam, Aminul

    2013-01-01

    a pair of thermoplastic materials (ABS and POM) were conducted. Three dimensional process simulations based on the finite element method have been performed to explore the capability of predicting filling pattern shape at component-level and surface micro feature-level in a polymer/polymer overmoulding...

  15. Ultrasonic detection technology based on joint robot on composite component with complex surface

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Juan; Xu, Chunguang; Zhang, Lan [School of Mechanical Engineering, Beijing Institute of Technology, Beijing (China)

    2014-02-18

    Some components have complex surface, such as the airplane wing and the shell of a pressure vessel etc. The quality of these components determines the reliability and safety of related equipment. Ultrasonic nondestructive detection is one of the main methods used for testing material defects at present. In order to improve the testing precision, the acoustic axis of the ultrasonic transducer should be consistent with the normal direction of the measured points. When we use joint robots, automatic ultrasonic scan along the component surface normal direction can be realized by motion trajectory planning and coordinate transformation etc. In order to express the defects accurately and truly, the robot position and the signal of the ultrasonic transducer should be synchronized.

  16. Characterizing Surface Energy Budget Components in Urban Regions Using Combination of Flux Tower Observations and Satellite Remote Sensing Measurements

    Science.gov (United States)

    Norouzi, H.; Vant-hull, B.; Ramamurthy, P.; Blake, R.; Prakash, D. S.

    2016-12-01

    Urban and built regions because of their lack of surface moisture and their surface impermeability significantly perform differently in surface energy budget than natural and non-urban regions. Characterizing the effect and the response of each surface type in the cities can help to increase our understanding of climate, anthropogenic heat, and urban heat islands. Both ground observations and remote sensing observations are important when the extent of the heat energy balance components in big cities is targeted. This is study aims to provide a novel approach to use ground observations and map the maxima and minima air temperature in New York City using satellite measurements. Complete energy balance stations are installed over distinct materials such as concrete, asphalt, and rooftops. The footprint of these stations is restricted to the individual materials. The energy balance stations monitor the sensible and latent heat fluxes through eddy covariance method. To account for the incoming and outgoing radiation, a 4-component radiometer is used that can observe both incoming and outgoing longwave and shortwave radiation. Moreover, satellite observations from Landsat 8 are utilized to classify the city surfaces to distinct defined surfaces where ground observations were performed. The mapped temperatures will be linked to MODIS surface temperatures to develop a model that can downscale MODIS skin temperatures to fine resolution air temperature over urban regions. The results are compared with ground observations, which they reveal a great potential of using synergetic use of flux tower observations and satellite measurement to study urban surface energy budget. The results of this study can enhance our understanding about urban heat islands as well as climate studies and their effects on the environment.

  17. The Effect of Surface Overburden on 2D Seismic Response

    Science.gov (United States)

    White, I.; Bongajum, E.; Milkereit, B.

    2009-05-01

    This study aims to investigate the effects of overburden layers in seismic surveys. Here, we look at the effect of low velocity, low density overburden on seismic imaging. Overburden layers continue to be a problem for recording and analyzing information in seismic surveys. Placing shots and receivers in or near an overburden layer can mask responses from deep subsurface structures and cause elastic wave scattering. To investigate this problem, a finite difference elastic wave modeling study was conducted to evaluate the effects of overburden layer when using 3-component surface or borehole receivers. In this study, models were used with a reflective, angled lens having the velocity and density parameters of a sulfide orebody. The depth of the overburden layer in the first model is uniform and the second layer varies sinusoidally. The parameters used for the overburden are 2.0 g/cm3 density, 600 m/s S-wave, and 2000 m/s P-wave; in contrast, the background parameters are 2.73 g/cm3 density, 3550 m/s S-wave, and 6140 m/s P-wave. The study looks at responses from the lens in models with and without the overburden layer. The relatively slow P-wave and S-wave velocity of the overburden material impacts the travel time and the shape of the wave. As expected with borehole receivers, only the first few traces are corrupted by highly dispersed surface waves while deeper receivers show clear reflections from the sulfide lens. The location of the shot also affects the seismic response depending on whether it originates inside the overburden or below.

  18. Designing Solutions using Response Surface Technique

    Directory of Open Access Journals (Sweden)

    COMAN Ovidiu

    2014-05-01

    Full Text Available In the present study a design of experiments method was used to obtain the most suitable responses. The variables that occur in the optimization are the movement of a dielectric material on Oy and Oz axis of a waveguide and the microwave power. The responses refer to the thermal field distribution, the reflected power, dielectric's temperature and the absorbed power.

  19. Tuning a fuzzy controller using quadratic response surfaces

    Science.gov (United States)

    Schott, Brian; Whalen, Thomas

    1992-01-01

    Response surface methodology, an alternative method to traditional tuning of a fuzzy controller, is described. An example based on a simulated inverted pendulum 'plant' shows that with (only) 15 trial runs, the controller can be calibrated using a quadratic form to approximate the response surface.

  20. Assessment of Wind Turbine Structural Integrity using Response Surface Methodology

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Svenningsen, Lasse; Moser, Wolfgang

    2016-01-01

    Highlights •A new approach to assessment of site specific wind turbine loads is proposed. •The approach can be applied in both fatigue and ultimate limit state. •Two different response surface methodologies have been investigated. •The model uncertainty introduced by the response surfaces is dete...

  1. NEXAFS characterization of DNA components and molecular-orientation of surface-bound DNA oligomers

    International Nuclear Information System (INIS)

    Samuel, Newton T.; Lee, C.-Y.; Gamble, Lara J.; Fischer, Daniel A.; Castner, David G.

    2006-01-01

    Single stranded DNA oligomers (ssDNA) immobilized onto solid surfaces forms the basis for several biotechnological applications such as DNA microarrays, affinity separations, and biosensors. Surface structure of Surface-bound oligomers is expected to significantly influence their biological activity and interactions with the environment. In this study near-edge X-ray absorption fine structure spectroscopy (NEXAFS) is used to characterize the components of DNA (nucleobases, nucleotides and nucleosides) and the orientation information of surface-bound ssDNA. The K-edges of carbon, nitrogen and oxygen have spectra with features that are characteristic of the different chemical species present in the nucleobases of DNA. The effect of addition of the DNA sugar and phosphate components on the NEXAFS K-edge spectra was also investigated. The polarization-dependent nitrogen K-edge NEXAFS data show significant changes for different orientations of surface bound ssDNA. These results establish NEXAFS as a powerful technique for chemical and structural characterization of surface-bound DNA oligomers

  2. An Integrated Surface Engineering Technology Development for Improving Energy Efficiency of Engine Components

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Hsu; Liming Chang; Huan Zhan

    2009-05-31

    Frictional losses are inherent in most practical mechanical systems. The ability to control friction offers many opportunities to achieve energy conservation. Over the years, materials, lubricants, and surface modifications have been used to reduce friction in automotive and diesel engines. However, in recent years, progress in friction reduction technology has slowed because many of the inefficiencies have been eliminated. A new avenue for friction reduction is needed. Designing surfaces specifically for friction reduction with concomitant enhanced durability for various engine components has emerged recently as a viable opportunity due to advances in fabrication and surface finishing techniques. Recently, laser ablated dimples on surfaces have shown friction reduction properties and have been demonstrated successfully in conformal contacts such as seals where the speed is high and the load is low. The friction reduction mechanism in this regime appears to depend on the size, patterns, and density of dimples in the contact. This report describes modeling efforts in characterizing surface textures and understanding their mechanisms for enhanced lubrication under high contact pressure conditions. A literature survey is first presented on the development of descriptors for irregular surface features. This is followed by a study of the hydrodynamic effects of individual micro-wedge dimples using the analytical solution of the 1-D Reynolds equation and the determination of individual components of the total friction resistance. The results obtained provide a better understanding of the dimple orientation effects and the approach which may be used to further compare the friction reduction provided by different texture patterns.

  3. Characterizing Mediterranean Land Surfaces as Component of the Regional Climate System by Remote Sensing

    Science.gov (United States)

    Bolle, H.-J.; Koslowsky, D.; Menenti, M.; Nerry, F.; Otterman, Joseph; Starr, D.

    1998-01-01

    Extensive areas in the Mediterranean region are subject to land degradation and desertification. The high variability of the coupling between the surface and the atmosphere affects the regional climate. Relevant surface characteristics, such as spectral reflectance, surface emissivity in the thermal-infrared region, and vegetation indices, serve as "primary" level indicators for the state of the surface. Their spatial, seasonal and interannual variability can be monitored from satellites. Using relationships between these primary data and combining them with prior information about the land surfaces (such as topography, dominant soil type, land use, collateral ground measurements and models), a second layer of information is built up which specifies the land surfaces as a component of the regional climate system. To this category of parameters which are directly involved in the exchange of energy, momentum and mass between the surface and the atmosphere, belong broadband albedo, thermodynamic surface temperature, vegetation types, vegetation cover density, soil top moisture, and soil heat flux. Information about these parameters finally leads to the computation of sensible and latent heat fluxes. The methodology was tested with pilot data sets. Full resolution, properly calibrated and normalized NOAA-AVHRR multi-annual primary data sets are presently compiled for the whole Mediterranean area, to study interannual variability and longer term trends.

  4. Applications of response surface methodology approach to ...

    African Journals Online (AJOL)

    Jane

    2011-08-22

    Aug 22, 2011 ... coronata germination and germ tube growth had followed a quadratic response function on temperature (R² = 0.94 and 0.97). On the other hand, the experimental values were in good agreement with the predicted ones and the model was highly significant with the correlation coefficient R being. 0.97 and ...

  5. Quantifying ecological thresholds from response surfaces

    Science.gov (United States)

    Heather E. Lintz; Bruce McCune; Andrew N. Gray; Katherine A. McCulloh

    2011-01-01

    Ecological thresholds are abrupt changes of ecological state. While an ecological threshold is a widely accepted concept, most empirical methods detect them in time or across geographic space. Although useful, these approaches do not quantify the direct drivers of threshold response. Causal understanding of thresholds detected empirically requires their investigation...

  6. Accuracy Assessment of Response Surface Approximations for Supersonic Turbine Design

    Science.gov (United States)

    Papila, Nilay; Papila, Melih; Shyy, Wei; Haftka, Raphael T.; FitzCoy, Norman

    2001-01-01

    There is a growing trend to employ CFD tools to supply the necessary information for design optimization of fluid dynamics components/systems. Such results are prone to uncertainties due to reasons including discretization. errors, incomplete convergence of computational procedures, and errors associated with physical models such as turbulence closures. Based on this type of information, gradient-based optimization algorithms often suffer from the noisy calculations, which can seriously compromise the outcome. Similar problems arise from the experimental measurements. Global optimization techniques, such as those based on the response surface (RS) concept are becoming popular in part because they can overcome some of these barriers. However, there are also fundamental issues related to such global optimization technique such as RS. For example, in high dimensional design spaces, typically only a small number of function evaluations are available due to computational and experimental costs. On the other hand, complex features of the design variables do not allow one to model the global characteristics of the design space with simple quadratic polynomials. Consequently a main challenge is to reduce the size of the region where we fit the RS, or make it more accurate in the regions where the optimum is likely to reside. Response Surface techniques using either polynomials or and Neural Network (NN) methods offer designers alternatives to conduct design optimization. The RS technique employs statistical and numerical techniques to establish the relationship between design variables and objective/constraint functions, typically using polynomials. In this study, we aim at addressing issues related to the following questions: (1) How to identify outliers associated with a given RS representation and improve the RS model via appropriate treatments? (2) How to focus on selected design data so that RS can give better performance in regions critical to design optimization? (3

  7. Simulated plasma facing component measurements for an in situ surface diagnostic on Alcator C-Moda)

    Science.gov (United States)

    Hartwig, Z. S.; Whyte, D. G.

    2010-10-01

    The ideal in situ plasma facing component (PFC) diagnostic for magnetic fusion devices would perform surface element and isotope composition measurements on a shot-to-shot (˜10 min) time scale with ˜1 μm depth and ˜1 cm spatial resolution over large areas of PFCs. To this end, the experimental adaptation of the customary laboratory surface diagnostic—nuclear scattering of MeV ions—to the Alcator C-Mod tokamak is being guided by ACRONYM, a Geant4 synthetic diagnostic. The diagnostic technique and ACRONYM are described, and synthetic measurements of film thickness for boron-coated PFCs are presented.

  8. Improvement in the surface quality of structural components produced by the RTM-process

    Energy Technology Data Exchange (ETDEWEB)

    Michaeli, W.; Dyckhoff, J. [Institute of Plastics Processing, Aachen (Germany)

    1993-12-31

    During the production of long or continuous fiber reinforced structural components in Resin Transfer Moulding (RTM), surface defects like voids, pinholes or unevenness frequently occur. These have to be repaired by manual labor before final painting. The conditions for the formation of voids in the laminate as well as surface defects are investigated by model experiments, making use of a window mould. Generally the resin is assumed to flow through the fiber reinforcement in a plug flow. The investigations indicate that advance either in the nonwovens of the surface or in the center of the laminate depends on the flow front velocity. This can be attributed to a superposition of capillary and flow effects. In order to obtain a high surface quality, the flow front velocity has to be kept within a material-related band width. Otherwise, areas of air enclosure in the laminate or surface defects like pinholes will result. With the aid of a steel mould with a large area, procedural variants are investigated to reduce surface faults and to decrease the air content in the laminate. The analysis indicates that the air content can be significantly reduced by injecting the resin into a cavity filled with gaseous acetone and increasing the cavity pressure during the time of curing. Furthermore the long and short-term waviness of the surface is improved by these process modifications.

  9. Mechanisms regulating osteoblast response to surface microtopography and vitamin D

    Science.gov (United States)

    Bell, Bryan Frederick, Jr.

    A comprehensive understanding of the interactions between orthopaedic and dental implant surfaces with the surrounding host tissue is essential in the design of advanced biomaterials that better promote bone growth and osseointegration of implants. Dental implants with roughened surfaces and high surface energy are well known to promote osteoblast differentiation in vitro and promote increased bone-to-implant contact in vivo. In addition, increased surface roughness increases osteoblasts response to the vitamin D metabolite 1alpha,25(OH)2D3. However, the exact mechanisms mediating cell response to surface properties and 1alpha,25(OH)2D3 are still being elucidated. The central aim of the thesis is to investigate whether integrin signaling in response to rough surface microtopography enhances osteoblast differentiation and responsiveness to 1alpha,25(OH)2D3. The hypothesis is that the integrin alpha5beta1 plays a role in osteoblast response to surface microtopography and that 1alpha,25(OH) 2D3 acts through VDR-independent pathways involving caveolae to synergistically enhance osteoblast response to surface roughness and 1alpha,25(OH) 2D3. To test this hypothesis the objectives of the studies performed in this thesis were: (1) to determine if alpha5beta 1 signaling is required for osteoblast response to surface microstructure; (2) to determine if increased responsiveness to 1alpha,25(OH)2D 3 requires the vitamin D receptor, (3) to determine if rough titanium surfaces functionalized with the peptides targeting integrins (RGD) and transmembrane proteoglycans (KRSR) will enhance both osteoblast proliferation and differentiation, and (4) to determine whether caveolae, which are associated with integrin and 1alpha,25(OH)2D3 signaling, are required for enhance osteogenic response to surface microstructure and 1alpha,25(OH)2D 3. The results demonstrate that integrins, VDR, and caveolae play important roles in mediating osteoblast response to surface properties and 1alpha,25

  10. [Determination of film thickness, component and content based on glass surface by using XRF spectrometry].

    Science.gov (United States)

    Mei, Yan; Ma, Mi-Xia; Nie, Zuo-Ren

    2013-12-01

    Film thickness, component and content based on glass surface were determined by using XRF technic, measure condition and instrument work condition in every layer were set and adjusted for the best measure effect for every element. Background fundamental parameter (BG-FP) method was built up. Measure results with this method were consistent with the actual preparation course and the method could fit to production application.

  11. Quantitative determination of the intensities of known components in spectra obtained from surface analytical techniques

    International Nuclear Information System (INIS)

    Nelson, G.C.

    1984-01-01

    Linear least-squares methods have been used to quantitatively decompose experimental data obtained from surface analytical techniques into its separate components. The mathematical procedure for accomplishing this is described and examples are given of the use of this method with data obtained from Auger electron spectroscopy [both N(E) and derivative], x-ray photoelectron spectroscopy, and low energy ion scattering spectroscopy. The requirements on the quality of the data are discussed

  12. Integrated-Optics Components Utilizing Long-Range Surface Plasmon Polaritons

    DEFF Research Database (Denmark)

    Boltasseva, Alexandra

    2004-01-01

    This thesis describes a new class of components for integrated optics, based on the propagation of long-range surface plasmon polaritons (LR-SPPs) along metal stripes embedded in a dielectric. These novel components can provide guiding of light as well as coupling and splitting from/into a number...... fabricated and optically characterized. At 1570 nm, coupling lengths of 1.9 and 0.8 mm are found for directional couplers with waveguides separated 4 and 0 µm, respectively. LR-SPP-based waveguides and waveguide components are modeled using the effective-refractive-index method and a good agreement...... with experimental results is obtained. The interaction of LR-SPPs with photonic crystals (PCs) is also studied. The PC structures are formed by periodic arrays of gold bumps that are arranged in a triangular lattice and placed symmetrically on both sides of a thin gold film. The LR-SPP transmission through...

  13. Eye surface temperature detects stress response in budgerigars (Melopsittacus undulatus).

    Science.gov (United States)

    Ikkatai, Yuko; Watanabe, Shigeru

    2015-08-05

    Previous studies have suggested that stressors not only increase body core temperature but also body surface temperature in many animals. However, it remains unclear whether surface temperature could be used as an alternative to directly measure body core temperature, particularly in birds. We investigated whether surface temperature is perceived as a stress response in budgerigars. Budgerigars have been used as popular animal models to investigate various neural mechanisms such as visual perception, vocal learning, and imitation. Developing a new technique to understand the basic physiological mechanism would help neuroscience researchers. First, we found that cloacal temperature correlated with eye surface temperature. Second, eye surface temperature increased after handling stress. Our findings suggest that eye surface temperature is closely related to cloacal temperature and that the stress response can be measured by eye surface temperature in budgerigars.

  14. Frequency response in surface-potential driven electrohydrodynamics

    DEFF Research Database (Denmark)

    Ejsing, Louise Wellendorph; Smistrup, Kristian; Pedersen, Christian Møller

    2006-01-01

    capacitance where the net flow rate is, in general, zero while harmonic rolls as well as time-averaged vortexlike components may exist depending on the spatial symmetry and extension of the surface potential. In general, the system displays a resonance behavior at a frequency corresponding to the inverse RC...... time of the system. Different surface potentials share the common feature that the resonance frequency is inversely proportional to the characteristic length scale of the surface potential. For the asymptotic frequency dependence above resonance we find a omega(-2) power law for surface potentials...

  15. Intelligent dual-responsive cellulose surfaces via surface-initiated ATRP.

    Science.gov (United States)

    Lindqvist, Josefina; Nyström, Daniel; Ostmark, Emma; Antoni, Per; Carlmark, Anna; Johansson, Mats; Hult, Anders; Malmström, Eva

    2008-08-01

    Novel thermo-responsive cellulose (filter paper) surfaces of N-isopropylacrylamide (NIPAAm) and pH-responsive cellulose surfaces of 4-vinylpyridine (4VP) have been achieved via surface-initiated ATRP. Dual-responsive (pH and temperature) cellulose surfaces were also obtained through the synthesis of block-copolymer brushes of PNIPAAm and P4VP. With changes in pH and temperature, these "intelligent" surfaces showed a reversible response to both individual triggers, as indicated by the changes in wettability from highly hydrophilic to highly hydrophobic observed by water contact angle measurements. Adjusting the composition of the grafted block-copolymer brushes allowed for further tuning of the wettability of these "intelligent" cellulose surfaces.

  16. 2D surface temperature measurement of plasma facing components with modulated active pyrometry

    International Nuclear Information System (INIS)

    Amiel, S.; Loarer, T.; Pocheau, C.; Roche, H.; Gauthier, E.; Aumeunier, M.-H.; Courtois, X.; Jouve, M.; Balorin, C.; Moncada, V.; Le Niliot, C.; Rigollet, F.

    2014-01-01

    In nuclear fusion devices, such as Tore Supra, the plasma facing components (PFC) are in carbon. Such components are exposed to very high heat flux and the surface temperature measurement is mandatory for the safety of the device and also for efficient plasma scenario development. Besides this measurement is essential to evaluate these heat fluxes for a better knowledge of the physics of plasma-wall interaction, it is also required to monitor the fatigue of PFCs. Infrared system (IR) is used to manage to measure surface temperature in real time. For carbon PFCs, the emissivity is high and known (ε ∼ 0.8), therefore the contribution of the reflected flux from environment and collected by the IR cameras can be neglected. However, the future tokamaks such as WEST and ITER will be equipped with PFCs in metal (W and Be/W, respectively) with low and variable emissivities (ε ∼ 0.1–0.4). Consequently, the reflected flux will contribute significantly in the collected flux by IR camera. The modulated active pyrometry, using a bicolor camera, proposed in this paper allows a 2D surface temperature measurement independently of the reflected fluxes and the emissivity. Experimental results with Tungsten sample are reported and compared with simultaneous measurement performed with classical pyrometry (monochromatic and bichromatic) with and without reflective flux demonstrating the efficiency of this method for surface temperature measurement independently of the reflected flux and the emissivity

  17. Surface engineering glass-metal coatings designed for induction heating of ceramic components

    International Nuclear Information System (INIS)

    Khan, Amir Azam; Labbe, Jean Claude

    2014-01-01

    The term Surface Engineering is of relatively recent origin and use, however, the use of coatings and treatments to render surfaces of materials more suitable for certain application or environment is not new. With the advent of Vacuum Technology, Surface Engineering has gained a whole new impetus, whereby expensive materials with adequate mechanical, chemical and thermal properties are being coated or treated on their surfaces in order to achieve what is called as Surface Engineered materials. The present paper presents an overview of recent achievements in Surface Engineering and gives a detailed view of a specific application where glass-metal composite coatings were deposited on ceramic components in order to render them sensitive to induction heating. Sintered glaze coatings containing silver particles in appropriate concentration can be used for the induction heating of porcelain. Mixtures of glass ceramic powders with silver are used to prepare self-transfer patterns, which are deposited over porcelain. Several configurations of these coatings, which are aesthetic to start with, are employed and heating patterns are recorded. The microstructure of these coatings is discussed in relation to the heating ability by a classical household induction system. The results show that this technique is practical and commercially viable

  18. Surface engineering glass-metal coatings designed for induction heating of ceramic components

    International Nuclear Information System (INIS)

    Khan, A. A.; Labbe, J. C.

    2013-01-01

    The term Surface Engineering is of relatively recent origin and use, however, the use of coatings and treatments to render surfaces of materials more suitable for certain application or environment is not new. With the advent of Vacuum Technology, Surface Engineering has gained a whole new impetus, whereby expensive materials with adequate mechanical, chemical and thermal properties are being coated or treated on their surfaces in order to achieve what is called as Surface Engineered materials. The present paper presents an overview of recent achievements in Surface Engineering and gives a detailed view of a specific application where glass-metal composite coatings were deposited on ceramic components in order to render them sensitive to induction heating. Sintered glaze coatings containing silver particles in appropriate concentration can be used for the induction heating of porcelain. Mixtures of glass ceramic powders with silver are used to prepare self-transfer patterns, which are deposited over porcelain. Several configurations of these coatings, which are aesthetic to start with, are employed and heating patterns are recorded. The microstructure of these coatings is discussed in relation to the heating ability by a classical household induction system. The results show that this technique is practical and commercially viable. (author)

  19. Assembling surface mounted components on ink-jet printed double sided paper circuit board

    International Nuclear Information System (INIS)

    Andersson, Henrik A; Manuilskiy, Anatoliy; Haller, Stefan; Sidén, Johan; Nilsson, Hans-Erik; Hummelgård, Magnus; Olin, Håkan; Hummelgård, Christine

    2014-01-01

    Printed electronics is a rapidly developing field where many components can already be manufactured on flexible substrates by printing or by other high speed manufacturing methods. However, the functionality of even the most inexpensive microcontroller or other integrated circuit is, at the present time and for the foreseeable future, out of reach by means of fully printed components. Therefore, it is of interest to investigate hybrid printed electronics, where regular electrical components are mounted on flexible substrates to achieve high functionality at a low cost. Moreover, the use of paper as a substrate for printed electronics is of growing interest because it is an environmentally friendly and renewable material and is, additionally, the main material used for many packages in which electronics functionalities could be integrated. One of the challenges for such hybrid printed electronics is the mounting of the components and the interconnection between layers on flexible substrates with printed conductive tracks that should provide as low a resistance as possible while still being able to be used in a high speed manufacturing process. In this article, several conductive adhesives are evaluated as well as soldering for mounting surface mounted components on a paper circuit board with ink-jet printed tracks and, in addition, a double sided Arduino compatible circuit board is manufactured and programmed. (paper)

  20. Strong surface effect on direct bulk flexoelectric response in solids

    International Nuclear Information System (INIS)

    Yurkov, A. S.; Tagantsev, A. K.

    2016-01-01

    In the framework of a continuum theory, it is shown that the direct bulk flexoelectric response of a finite sample essentially depends on the surface polarization energy, even in the thermodynamic limit where the body size tends to infinity. It is found that a modification of the surface energy can lead to a change in the polarization response by a factor of two. The origin of the effect is an electric field produced by surface dipoles induced by the strain gradient. The unexpected sensitivity of the polarization response to the surface energy in the thermodynamic limit is conditioned by the fact that the moments of the surface dipoles may scale as the body size

  1. Response of surface buoy moorings in steady and wave flows

    Digital Repository Service at National Institute of Oceanography (India)

    Anand, N.M.; Nayak, B.U.; SanilKumar, V.

    A numerical model has been developed to evaluate the dynamics of surface buoy mooring systems under wave and current loading. System tension response and variation of tension in the mooring line at various depths have been evaluated for deep water...

  2. Response surface optimization of D(-)-lactic acid production by ...

    African Journals Online (AJOL)

    Response surface optimization of D(-)-lactic acid production by Lactobacillus SMI8 using corn steep liquor and yeast autolysate as an alternative nitrogen source. CJ Bolner de Lima, LF Coelho, KC Blanco, J Contiero ...

  3. Response surface methodology of nitrilase production by recombinant Escherichia coli.

    Science.gov (United States)

    Dubey, Sachin; Singh, Amit; Banerjee, Uttam C

    2011-07-01

    Growth and nitrilase production by recombinant Escherichia coli cells harbouring pET 21 (b) plasmid, for the expression of Pseudomonas putida nitrilase were improved using response surface methodology. Central composite design was used for obtaining ideal concentration of critical medium components which include fructose, tryptone, yeast extract and lactose. The optimal values for the concentration of fructose, tryptone, yeast extract and lactose were found to be 1.13, 2.26, 3.25 and 0.9 % (w/v), respectively. Here, fructose served as carbon source for the growth while lactose was preferably used as inducer for the expression of foreign protein. Yeast extract in the medium was used as a growth promoter while tryptone was added as a major nitrogen source. Using this optimized medium, an experimental growth of 6.67 (OD at 600 nm) and nitrilase activity of 27.13 U/ml was achieved. This approach for medium development led to an enhancement of the growth and enzyme activity by 1.4 and 2.2 times, respectively, as compared to the un-optimized medium.

  4. Response surface methodology of nitrilase production by recombinant Escherichia coli

    Directory of Open Access Journals (Sweden)

    Sachin Dubey

    2011-09-01

    Full Text Available Growth and nitrilase production by recombinant Escherichia coli cells harbouring pET 21 (b plasmid, for the expression of Pseudomonas putida nitrilase were improved using response surface methodology. Central composite design was used for obtaining ideal concentration of critical medium components which include fructose, tryptone, yeast extract and lactose. The optimal values for the concentration of fructose, tryptone, yeast extract and lactose were found to be 1.13, 2.26, 3.25 and 0.9 % (w/v, respectively. Here, fructose served as carbon source for the growth while lactose was preferably used as inducer for the expression of foreign protein. Yeast extract in the medium was used as a growth promoter while tryptone was added as a major nitrogen source. Using this optimized medium, an experimental growth of 6.67 (OD at 600 nm and nitrilase activity of 27.13 U/ml was achieved. This approach for medium development led to an enhancement of the growth and enzyme activity by 1.4 and 2.2 times, respectively, as compared to the un-optimized medium.

  5. GumPack: A Personal Health Assistant with Reconfigurable Surface Components

    Directory of Open Access Journals (Sweden)

    Kejia Li

    2013-01-01

    Full Text Available Wearable and everyday-carry medical devices can improve quality of life for individuals that need frequent health monitoring. Such tools can supplement ubiquitous home care environments populated with medical sensors, extending the reach of these environments and increasing the freedom of their occupants. This paper presents the concept design for an everyday-carry medical device called a ‘GumPack’: a small cuboid-shaped device that offers wireless connectivity and plug-and-play surface components, where a component can be a biomedical sensor or a wireless network coordinator that manages a body area network. This geometrical layout optimizes access to surface-based medical hardware mounted on a small form factor. The device offers substantive computing power, supports local component reconfigurability, and promotes interoperability with medical device coordination environments. The GumPack is envisioned to be a personal health assistant carried in a pocket or handbag that can operate alone or interface to, e.g., a cell phone.

  6. Lactic acid bacteria in dairy food: surface characterization and interactions with food matrix components.

    Science.gov (United States)

    Burgain, J; Scher, J; Francius, G; Borges, F; Corgneau, M; Revol-Junelles, A M; Cailliez-Grimal, C; Gaiani, C

    2014-11-01

    This review gives an overview of the importance of interactions occurring in dairy matrices between Lactic Acid Bacteria and milk components. Dairy products are important sources of biological active compounds of particular relevance to human health. These compounds include immunoglobulins, whey proteins and peptides, polar lipids, and lactic acid bacteria including probiotics. A better understanding of interactions between bioactive components and their delivery matrix may successfully improve their transport to their target site of action. Pioneering research on probiotic lactic acid bacteria has mainly focused on their host effects. However, very little is known about their interaction with dairy ingredients. Such knowledge could contribute to designing new and more efficient dairy food, and to better understand relationships between milk constituents. The purpose of this review is first to provide an overview of the current knowledge about the biomolecules produced on bacterial surface and the composition of the dairy matter. In order to understand how bacteria interact with dairy molecules, adhesion mechanisms are subsequently reviewed with a special focus on the environmental conditions affecting bacterial adhesion. Methods dedicated to investigate the bacterial surface and to decipher interactions between bacteria and abiotic dairy components are also detailed. Finally, relevant industrial implications of these interactions are presented and discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Identifying Industry-Specific Components of Product Liability Response System Using Delphi-AHP Method

    Directory of Open Access Journals (Sweden)

    Seo JunHyeok

    2016-12-01

    Full Text Available PL (product liability response system is an enterprise-wide system that prevents company’s financial loss due to PL-related accidents. Existing researches on PL response system are mainly focused on preventive and/or defense strategies for the companies. Also, it is obvious that each industry has their original characteristics related on PL issues. It means industry-specific characteristics should be considered to adopt PL response strategies. Thus, this paper aims to discuss industry-specific PL response system and their components. Based on prior researches, we tried to reveal the possibility of its application to manufacturing companies of existing PL response strategies using Delphi method with PL experts. Based on first round results, we tried to classify existing PL strategies of manufacturing companies into several categories. To validate our suggestion for essential components of PL response system, second round Delphi method are applied. Analytic hierarchy process (AHP technique will be applied to identify a prioritized list of each components and strategies. Existing PL response strategies could be categorized with six components – strategy, technology, investment, training, awareness, and organization. Among six components, Technology – it represents the technology needed for improving the safety of all products – is the most important components to prepare PL accidents. The limitation of this paper is on the size of survey and variety of examples. However, the future study will enhance the potential of the proposed method. Regardless of rich research efforts to identify PL response strategies, there is no effort to categorize these strategies and prioritized them. Well-coordinated and actionable PL response strategies and their priorities could help small-and-medium sized enterprise (SME to develop their own PL response system with their limited resources.

  8. Tunnel flexibility effect on the ground surface acceleration response

    Science.gov (United States)

    Baziar, Mohammad Hassan; Moghadam, Masoud Rabeti; Choo, Yun Wook; Kim, Dong-Soo

    2016-09-01

    Flexibility of underground structures relative to the surrounding medium, referred to as the flexibility ratio, is an important factor that influences their dynamic interaction. This study investigates the flexibility effect of a box-shaped subway tunnel, resting directly on bedrock, on the ground surface acceleration response using a numerical model verified against dynamic centrifuge test results. A comparison of the ground surface acceleration response for tunnel models with different flexibility ratios revealed that the tunnels with different flexibility ratios influence the acceleration response at the ground surface in different ways. Tunnels with lower flexibility ratios have higher acceleration responses at short periods, whereas tunnels with higher flexibility ratios have higher acceleration responses at longer periods. The effect of the flexibility ratio on ground surface acceleration is more prominent in the high range of frequencies. Furthermore, as the flexibility ratio of the tunnel system increases, the acceleration response moves away from the free field response and shifts towards the longer periods. Therefore, the flexibility ratio of the underground tunnels influences the peak ground acceleration (PGA) at the ground surface, and may need to be considered in the seismic zonation of urban areas.

  9. Thermographic analysis of plasma facing components covered by carbon surface layer in tokamaks

    International Nuclear Information System (INIS)

    Gardarein, Jean-Laurent

    2007-01-01

    Tokamaks are reactors based on the thermonuclear fusion energy with magnetic confinement of the plasma. In theses machines, several MW are coupled to the plasma for about 10 s. A large part of this power is directed towards plasma facing components (PFC). For better understanding and control the heat flux transfer from the plasma to the surrounding wall, it is very important to measure the surface temperature of the PFC and to estimate the imposed heat flux. In most of tokamaks using carbon PFC, the eroded carbon is circulating in the plasma and redeposited elsewhere. During the plasma operations, this leads at some locations to the formation of thin or thick carbon layers usually poorly attached to the PFC. These surface layers with unknown thermal properties complicate the calculation of the heat flux from IR surface temperature measurements. To solve this problem, we develop first, inverse method to estimate the heat flux using thermocouple (not sensitive to the carbon surface layers) temperature measurements. Then, we propose a front face pulsed photothermal method allowing an estimation of layers thermal diffusivity, conductivity, effusivity and the thermal contact resistance between the layer and the tile. The principle is to study with an infrared sensor, the cooling of the layer surface after heating by a short laser pulse, this cooling depending on the thermal properties of the successive layers. (author) [fr

  10. Components of the regular surface array of Aquaspirillum serpens MW5 and their assembly in vitro.

    Science.gov (United States)

    Kist, M L; Murray, R G

    1984-02-01

    The two-layered regular surface array of Aquaspirillum serpens MW5 was removed from cell envelopes and dissociated into subunits by treatment with 6 M urea. The surface components reassembled onto an outer membrane surface and self-assembled into planar sheets in vitro in the presence of Ca2+ or Sr2+. The two layers were removed sequentially from cell envelopes by a two-step extraction procedure involving initial treatment with a high-pH buffer to remove the outermost surface layer and subsequent treatment with 6 M urea to remove the innermost layer. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the outer and inner layers of the array were composed of two proteins with molecular weights of 125,000 and 150,000, respectively. The two layers assembled sequentially; the 150,000-molecular-weight protein formed an array on an outer membrane surface, and the 125,000-molecular-weight protein required that array as a template for its in vitro assembly.

  11. Surface inspection system for industrial components based on shape from shading minimization approach

    Science.gov (United States)

    Kotan, Muhammed; Öz, Cemil

    2017-12-01

    An inspection system using estimated three-dimensional (3-D) surface characteristics information to detect and classify the faults to increase the quality control on the frequently used industrial components is proposed. Shape from shading (SFS) is one of the basic and classic 3-D shape recovery problems in computer vision. In our application, we developed a system using Frankot and Chellappa SFS method based on the minimization of the selected basis function. First, the specialized image acquisition system captured the images of the component. To eliminate noise, wavelet transform is applied to the taken images. Then, estimated gradients were used to obtain depth and surface profiles. Depth information was used to determine and classify the surface defects. Also, a comparison made with some linearization-based SFS algorithms was discussed. The developed system was applied to real products and the results indicated that using SFS approaches is useful and various types of defects can easily be detected in a short period of time.

  12. Osteoblastic response to pectin nanocoating on titanium surfaces

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna; Svava, Rikke; Yihua, Yu

    2014-01-01

    Osseointegration of titanium implants can be improved by organic and inorganic nanocoating of the surface. The aim of our study was to evaluate the effect of organic nanocoating of titanium surface with unmodified and modified pectin Rhamnogalacturonan-Is (RG-Is) isolated from potato and apple...... with respect to surface properties and osteogenic response in osteoblastic cells. Nanocoatings on titanium surfaces were evaluated by scanning electron microscopy, contact angle measurements, atomic force microscopy, and X-ray photoelectron spectroscopy. The effect of coated RG-Is on cell adhesion, cell...... galactose produced higher level of mineralized matrix compared with control surfaces and surfaces coated with RG-I with low content of linear 1.4-linked galactose. The study showed that the pectin RG-Is nanocoating not only changed chemical and physical titanium surface properties, but also specific coating...

  13. Response surface method applied to optimization of estradiol ...

    Indian Academy of Sciences (India)

    An optimization process based on response surface methodology was carried out in order to develop a statistical model which describes the relationship between active independent variables and estradiol flux. This model can be used to find out a combination of factor levels during response optimization. Possible options ...

  14. Methodology for estimating realistic responses of buildings and components under earthquake motion and its application

    International Nuclear Information System (INIS)

    Ebisawa, Katsumi; Abe, Kiyoharu; Kohno, Kunihiko; Nakamura, Hidetaka; Itoh, Mamoru.

    1996-11-01

    Failure probabilities of buildings and components under earthquake motion are estimated as conditional probabilities that their realistic responses exceed their capacities. Two methods for estimating their failure probabilities have already been developed. One is a detailed method developed in the Seismic Safety margins Research Program of Lawrence Livermore National Laboratory in U.S.A., which is called 'SSMRP method'. The other is a simplified method proposed by Kennedy et al., which is called 'Zion method'. The Zion method is sometimes called 'response factor method'. The authors adopted the response factor method. In order to enhance the estimation accuracy of failure probabilities of buildings and components, however, a new methodology for improving the response factor method was proposed. Based on the improved method, response factors of buildings and components designed to seismic design standard in Japan were estimated, and their realistic responses were also calculated. By using their realistic responses and capacities, the failure probabilities of a reactor building and relays were estimated. In order to identify the difference between new method, SSMRP method and original response factor method, the failure probabilities were compared estimated by these three methods. A similar method of SSMRP was used instead of the original SSMRP for saving time and labor. The viewpoints for selecting the methods to estimate failure probabilities of buildings and components were also proposed. (author). 55 refs

  15. Preliminary Assessment of Seals for Dust Mitigation of Mechanical Components for Lunar Surface Systems

    Science.gov (United States)

    Delgado, Irebert R.; Handschuh, Michael J.

    2010-01-01

    Component tests were conducted on spring-loaded Teflon seals to determine their performance in keeping lunar simulant out of mechanical component gearbox, motor, and bearing housings. Baseline tests were run in a dry-room without simulant for 10,000 cycles to determine wear effects of the seal against either anodized aluminum or stainless steel shafts. Repeat tests were conducted using lunar simulants JSC-1A and LHT-2M. Finally, tests were conducted with and without simulant in vacuum at ambient temperature. Preliminary results indicate minimal seal and shaft wear through 10,000 cycles, and more importantly, no simulant was observed to pass through the seal-shaft interface. Future endurance tests are planned at relevant NASA Lunar Surface System architecture shaft sizes and operating conditions.

  16. Proceedings of the joint meeting on Plasma Surface Interaction (PSI) and Plasma Facing Components (PFC)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The joint meeting on Plasma Surface Interaction (PSI) and Plasma Facing Components (PFC) was held in Naka Fusion Establishment on December 1, 2000. This meeting has been held to enhance information exchange between PSI and PFC researchers. In the present meeting, there were 11 presentations which covered current status of PSI and PFC studies for large fusion devices such as ITER, JT-60 and LHD, and basic studies on Hydrogen isotope behavior in the fusion material. This report includes abstracts and view graphs of these presentations. (author)

  17. Principal component analysis of bacteria using surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Guicheteau, Jason; Christesen, Steven D.

    2006-05-01

    Surface-enhanced Raman scattering (SERS) provides rapid fingerprinting of biomaterial in a non-destructive manner. The problem of tissue fluorescence, which can overwhelm a normal Raman signal from biological samples, is largely overcome by treatment of biomaterials with colloidal silver. This work presents a study into the applicability of qualitative SER spectroscopy with principal component analysis (PCA) for the discrimination of four biological threat simulants; Bacillus globigii, Pantoea agglomerans, Brucella noetomae, and Yersinia rohdei. We also demonstrate differentiation of gram-negative and gram-positive species and as well as spores and vegetative cells of Bacillus globigii.

  18. Principal component analysis for surface reflection components and structure in the facial image and synthesis of the facial image in various ages

    Science.gov (United States)

    Hirose, Misa; Toyota, Saori; Ojima, Nobutoshi; Ogawa-Ochiai, Keiko; Tsumura, Norimichi

    2015-03-01

    In this paper, principal component analysis is applied to pigmentation distributions, surface reflectance components and facial landmarks in the whole facial images to obtain feature values. Furthermore, the relationship between the obtained feature vectors and age is estimated by multiple regression analysis to modulate facial images in woman of ages 10 to 70. In our previous work, we analyzed only pigmentation distributions and the reproduced images looked younger than the reproduced age by the subjective evaluation. We considered that this happened because we did not modulate the facial structures and detailed surfaces such as wrinkles. By analyzing landmarks represented facial structures and surface reflectance components, we analyzed the variation of facial structures and fine asperity distributions as well as pigmentation distributions in the whole face. As a result, our method modulate the appearance of a face by changing age more appropriately.

  19. Modification of the cellulosic component of hemp fibers using sulfonic acid derivatives: Surface and thermal characterization.

    Science.gov (United States)

    George, Michael; Mussone, Paolo G; Bressler, David C

    2015-12-10

    The aim of this study was to characterize the surface, morphological, and thermal properties of hemp fibers treated with two commercially available, inexpensive, and water soluble sulfonic acid derivatives. Specifically, the cellulosic component of the fibers were targeted, because cellulose is not easily removed during chemical treatment. These acids have the potential to selectively transform the surfaces of natural fibers for composite applications. The proposed method proceeds in the absence of conventional organic solvents and high reaction temperatures. Surface chemical composition and signature were measured using gravimetric analysis, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red spectroscopy (FTIR). XPS data from the treated hemp fibers were characterized by measuring the reduction in O/C ratio and an increase in abundance of the C-C-O signature. FTIR confirmed the reaction with the emergence of peaks characteristic of disubstituted benzene and amino groups. Grafting of the sulfonic derivatives resulted in lower surface polarity. Thermogravimetric analysis revealed that treated fibers were characterized by lower percent degradation between 200 and 300 °C, and a higher initial degradation temperature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Titanium surface hydrophilicity modulates the human macrophage inflammatory cytokine response.

    Science.gov (United States)

    Alfarsi, Mohammed A; Hamlet, Stephen M; Ivanovski, Saso

    2014-01-01

    Increased titanium surface hydrophilicity has been shown to accelerate dental implant osseointegration. Macrophages are important in the early inflammatory response to surgical implant placement and influence the subsequent healing response. This study investigated the modulatory effect of a hydrophilic titanium surface on the inflammatory cytokine expression profile in a human macrophage cell line (THP-1). Genes for 84 cytokines, chemokines, and their receptors were analyzed following exposure to (1) polished (SMO), (2) micro-rough sand blasted, acid etched (SLA), and (3) hydrophilic-modified SLA (modSLA) titanium surfaces for 1 and 3 days. By day 3, the SLA surface elicited a pro-inflammatory response compared to the SMO surface with statistically significant up-regulation of 16 genes [Tumor necrosis factor (TNF) Interleukin (IL)-1β, Chemokine (C-C motif) ligand (CCL)-1, 2, 3, 4, 18, 19, and 20, Chemokine (C-X-C motif) ligand (CXCL)-1, 5, 8 and 12, Chemokine (C-C motif) receptor (CCR)-7, Lymphotoxin-beta (LTB), and Leukotriene B4 receptor (LTB4R)]. This effect was countered by the modSLA surface, which down-regulated the expression of 10 genes (TNF, IL-1α and β, CCL-1, 3, 19 and 20, CXCL-1 and 8, and IL-1 receptor type 1), while two were up-regulated (osteopontin and CCR5) compared to the SLA surface. These cytokine gene expression changes were confirmed by decreased levels of corresponding protein secretion in response to modSLA compared to SLA. These results show that a hydrophilic titanium surface can modulate human macrophage pro-inflammatory cytokine gene expression and protein secretion. An attenuated pro-inflammatory response may be an important molecular mechanism for faster and/or improved wound healing. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

  1. Responses of fibroblasts and glial cells to nanostructured platinum surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Pennisi, C P; Sevcencu, C; Yoshida, K [Center for Sensory-Motor Interaction (SMI), Aalborg University, Aalborg (Denmark); Dolatshahi-Pirouz, A; Foss, M; Larsen, A Nylandsted; Besenbacher, F [Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus (Denmark); Hansen, J Lundsgaard [Department of Physics and Astronomy, Aarhus University, Aarhus (Denmark); Zachar, V, E-mail: cpennisi@hst.aau.d [Laboratory for Stem Cell Research, Aalborg University (Denmark)

    2009-09-23

    The chronic performance of implantable neural prostheses is affected by the growth of encapsulation tissue onto the stimulation electrodes. Encapsulation is associated with activation of connective tissue cells at the electrode's metallic contacts, usually made of platinum. Since surface nanotopography can modulate the cellular responses to materials, the aim of the present work was to evaluate the 'in vitro' responses of connective tissue cells to platinum strictly by modulating its surface nanoroughness. Using molecular beam epitaxy combined with sputtering, we produced platinum nanostructured substrates consisting of irregularly distributed nanopyramids and investigated their effect on the proliferation, cytoskeletal organization and cellular morphology of primary fibroblasts and transformed glial cells. Cells were cultured on these substrates and their responses to surface roughness were studied. After one day in culture, the fibroblasts were more elongated and their cytoskeleton less mature when cultured on rough substrates. This effect increased as the roughness of the surface increased and was associated with reduced cell proliferation throughout the observation period (4 days). Morphological changes also occurred in glial cells, but they were triggered by a different roughness scale and did not affect cellular proliferation. In conclusion, surface nanotopography modulates the responses of fibroblasts and glial cells to platinum, which may be an important factor in optimizing the tissue response to implanted neural electrodes.

  2. Responses of fibroblasts and glial cells to nanostructured platinum surfaces

    Science.gov (United States)

    Pennisi, C. P.; Sevcencu, C.; Dolatshahi-Pirouz, A.; Foss, M.; Lundsgaard Hansen, J.; Nylandsted Larsen, A.; Zachar, V.; Besenbacher, F.; Yoshida, K.

    2009-09-01

    The chronic performance of implantable neural prostheses is affected by the growth of encapsulation tissue onto the stimulation electrodes. Encapsulation is associated with activation of connective tissue cells at the electrode's metallic contacts, usually made of platinum. Since surface nanotopography can modulate the cellular responses to materials, the aim of the present work was to evaluate the 'in vitro' responses of connective tissue cells to platinum strictly by modulating its surface nanoroughness. Using molecular beam epitaxy combined with sputtering, we produced platinum nanostructured substrates consisting of irregularly distributed nanopyramids and investigated their effect on the proliferation, cytoskeletal organization and cellular morphology of primary fibroblasts and transformed glial cells. Cells were cultured on these substrates and their responses to surface roughness were studied. After one day in culture, the fibroblasts were more elongated and their cytoskeleton less mature when cultured on rough substrates. This effect increased as the roughness of the surface increased and was associated with reduced cell proliferation throughout the observation period (4 days). Morphological changes also occurred in glial cells, but they were triggered by a different roughness scale and did not affect cellular proliferation. In conclusion, surface nanotopography modulates the responses of fibroblasts and glial cells to platinum, which may be an important factor in optimizing the tissue response to implanted neural electrodes.

  3. Protection of surface assets on Mars from wind blown jettisoned spacecraft components

    Science.gov (United States)

    Paton, Mark

    2017-07-01

    Jettisoned Entry, Descent and Landing System (EDLS) hardware from landing spacecraft have been observed by orbiting spacecraft, strewn over the Martian surface. Future Mars missions that land spacecraft close to prelanded assets will have to use a landing architecture that somehow minimises the possibility of impacts from these jettisoned EDLS components. Computer modelling is used here to investigate the influence of wind speed and direction on the distribution of EDLS components on the surface. Typical wind speeds encountered in the Martian Planetary Boundary Layer (PBL) were found to be of sufficient strength to blow items having a low ballistic coefficient, i.e. Hypersonic Inflatable Aerodynamic Decelerators (HIADs) or parachutes, onto prelanded assets even when the lander itself touches down several kilometres away. Employing meteorological measurements and careful characterisation of the Martian PBL, e.g. appropriate wind speed probability density functions, may then benefit future spacecraft landings, increase safety and possibly help reduce the delta v budget for Mars landers that rely on aerodynamic decelerators.

  4. The Effects of Laterite and Associated Terrain Components on PBMR Response in HAPEX-Sahel

    Science.gov (United States)

    Teng, William L.; Choudhury, Bhaskar J.; Wang, James R.

    1997-01-01

    Terrain characteristics such as roughness and vegetation have been shown to significantly affect the interpretation of microwave brightness temperatures (T(B)s) for mapping soil moisture. This study, a part of the 1992 HAPEX-Sahel experiment (Hydrologic Atmospheric Pilot Experiment in the Sahel), aimed to determine the effects of laterite and associated terrain components (i.e. vegetation, soil, and exposed water bodies) on the T(B) response of the Pushbroom Microwave Radiometer (PBMR, L-band, 21 cm wavelength), using the NS001 Thematic Mapper Simulator data as a surrogate for ground data. Coincident PBMR and NS001 data acquired from the high altitude (about 1500 m) long transect flights were processed to obtain TBs and radiances, respectively. The transects covered a range of moisture conditions. For this preliminary evaluation, no atmospheric corrections were applied, and the data sets were aligned by matching the acquisition times of the data records. NS001 pixels (about 4 m) were averaged to approximate the resolution of the PBMR (about 450 m), before their flight line data were compared. The laterite plateaux were found to have a surprisingly strong effect on the PBMR T(B) response. T(B) variations along the flight line could largely be explained by a combination of density and dielectric properties of laterite. The effect of surface moisture was distinguishable from the laterite effect, with the distinction apparently related to the occurrence of ephemeral pools of water after rainfall. Model simulated T(B)s agreed reasonably well with the observed T(B)s.

  5. Mechanism study of initial filamentary damage in optical components owing to surface contamination particles

    Science.gov (United States)

    Sun, Xiaoyan; Lei, Zemin; Lu, Xingqiang; Fan, Dianyuan

    2015-07-01

    Contaminations existing inevitably in high-power laser facilities modulate laser beams and decrease beam quality. This study set up a detection system to study the mechanism of initial filamentary damage in optical components induced by surface contaminations. The effect of ordinary solid particles, liquid particles, and solid-liquid mixed particles on the near-field intensity distribution of laser beam was studied and analyzed statistically. The experiment results show that pure solid particles make the beam generate diffraction rings with dark center usually in the shadow of the particles which is a weak intensity modulation; pure liquid particles focus the localized beam into a bright spot rapidly, but it is diffracted away soon; solid-liquid mixed particles cause diffraction rings with strongly bright center, but the high local intensity can be diffracted away only after a longer distance, which is one of the reason that induces the initial filamentary damage to optical components. The research results can predict the likelihood of component damage, and the corresponding preventive measures help to keep the safe operation of high-power laser facilities.

  6. Electroantennographic responses of New World screwworm to components of swormlure-4 and related compounds

    International Nuclear Information System (INIS)

    Cork, A.

    1992-01-01

    Electroantennographic (EAG) responses from New World screwworm flies were recorded as dose-response curves to the components of swormlure and to isobutyric acid, butanol, 1-hexanol, 1-octen-3-o1, 3-propylphenol and 3-methylindole. Among the swormlure components, good responses were obtained to valeric acid, phenol 4-methylphenol and indole. Only weaker responses were obtained to the butyl alcohols, dimethyldisulphide, acetic, butyric and benzoic acids. A strong response was obtained to 1-octen-3-o1, and the response to 3-methylindole was greater than that to indole. Responses of male and female flies were generally similar, except for those to dimethylsulphide and 4-methylphenol where responses fo males were greater than those of females. These studies indicate that EAG linked to gas chromatography should be a useful technique for detection of the biologically-active components in naturally-derived, volatile attractants, and suggest 1-octen-3-o1 and 3- methylindole should be tested for behavioural effects on NWS. 7 figs

  7. Response Ant Colony Optimization of End Milling Surface Roughness

    Directory of Open Access Journals (Sweden)

    Ahmed N. Abd Alla

    2010-03-01

    Full Text Available Metal cutting processes are important due to increased consumer demands for quality metal cutting related products (more precise tolerances and better product surface roughness that has driven the metal cutting industry to continuously improve quality control of metal cutting processes. This paper presents optimum surface roughness by using milling mould aluminium alloys (AA6061-T6 with Response Ant Colony Optimization (RACO. The approach is based on Response Surface Method (RSM and Ant Colony Optimization (ACO. The main objectives to find the optimized parameters and the most dominant variables (cutting speed, feedrate, axial depth and radial depth. The first order model indicates that the feedrate is the most significant factor affecting surface roughness.

  8. Autonomous Aerobraking: Thermal Analysis and Response Surface Development

    Science.gov (United States)

    Dec, John A.; Thornblom, Mark N.

    2011-01-01

    A high-fidelity thermal model of the Mars Reconnaissance Orbiter was developed for use in an autonomous aerobraking simulation study. Response surface equations were derived from the high-fidelity thermal model and integrated into the autonomous aerobraking simulation software. The high-fidelity thermal model was developed using the Thermal Desktop software and used in all phases of the analysis. The use of Thermal Desktop exclusively, represented a change from previously developed aerobraking thermal analysis methodologies. Comparisons were made between the Thermal Desktop solutions and those developed for the previous aerobraking thermal analyses performed on the Mars Reconnaissance Orbiter during aerobraking operations. A variable sensitivity screening study was performed to reduce the number of variables carried in the response surface equations. Thermal analysis and response surface equation development were performed for autonomous aerobraking missions at Mars and Venus.

  9. Osteoblastic response to pectin nanocoating on titanium surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gurzawska, Katarzyna, E-mail: kagu@sund.ku.dk [Research Center for Ageing and Osteoporosis, Departments of Medicine and Diagnostics, Copenhagen University Hospital Glostrup, Ndr. Ringvej 57, 2600 Glostrup (Denmark); Institute of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Nørre Allé 20, 2200 Copenhagen N (Denmark); Svava, Rikke [Department of Plant Environment Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Copenhagen Center for Glycomics, Institute for Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N (Denmark); Yihua, Yu; Haugshøj, Kenneth Brian [Microtechnology and Surface Analysis, Danish Technological Institute, Gregersensvej 8, 2630 Taastrup (Denmark); Dirscherl, Kai [Dansk Fundamental Metrologi A/S, Matematiktorvet 307, 2800 Lyngby (Denmark); Levery, Steven B. [Copenhagen Center for Glycomics, Institute for Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N (Denmark); Byg, Inge [Department of Plant Environment Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Damager, Iben [Novozymes A/S, Krogshoejvej 36, 2880 Bagsvaerd (Denmark); Nielsen, Martin W. [Department of Systems Biology, Technical University of Denmark, Matematiktorvet, Building 301, Kgs. Lyngby DK-2800 (Denmark); Jørgensen, Bodil [Department of Plant Environment Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Jørgensen, Niklas Rye [Research Center for Ageing and Osteoporosis, Departments of Medicine and Diagnostics, Copenhagen University Hospital Glostrup, Ndr. Ringvej 57, 2600 Glostrup (Denmark); and others

    2014-10-01

    Osseointegration of titanium implants can be improved by organic and inorganic nanocoating of the surface. The aim of our study was to evaluate the effect of organic nanocoating of titanium surface with unmodified and modified pectin Rhamnogalacturonan-Is (RG-Is) isolated from potato and apple with respect to surface properties and osteogenic response in osteoblastic cells. Nanocoatings on titanium surfaces were evaluated by scanning electron microscopy, contact angle measurements, atomic force microscopy, and X-ray photoelectron spectroscopy. The effect of coated RG-Is on cell adhesion, cell viability, bone matrix formation and mineralization was tested using SaOS-2 cells. Nanocoating with pectin RG-Is affected surface properties and in consequence changed the environment for cellular response. The cells cultured on surfaces coated with RG-Is from potato with high content of linear 1.4-linked galactose produced higher level of mineralized matrix compared with control surfaces and surfaces coated with RG-I with low content of linear 1.4-linked galactose. The study showed that the pectin RG-Is nanocoating not only changed chemical and physical titanium surface properties, but also specific coating with RG-Is containing high amount of galactan increased mineralized matrix formation of osteoblastic cells in vitro. - Highlights: • Surface nanocoating with plant-derived Rhamnogalacturonan-I (RG-I) is proposed. • Titanium surface became more hydrophilic after RG-Is nanocoating. • RG-Is with high galactose content resulted in high level of mineralized matrix. • RG-I is a new candidate for improvement of bone healing and osseointegration.

  10. Test-Anchored Vibration Response Predictions for an Acoustically Energized Curved Orthogrid Panel with Mounted Components

    Science.gov (United States)

    Frady, Gregory P.; Duvall, Lowery D.; Fulcher, Clay W. G.; Laverde, Bruce T.; Hunt, Ronald A.

    2011-01-01

    rich body of vibroacoustic test data was recently generated at Marshall Space Flight Center for component-loaded curved orthogrid panels typical of launch vehicle skin structures. The test data were used to anchor computational predictions of a variety of spatially distributed responses including acceleration, strain and component interface force. Transfer functions relating the responses to the input pressure field were generated from finite element based modal solutions and test-derived damping estimates. A diffuse acoustic field model was applied to correlate the measured input sound pressures across the energized panel. This application quantifies the ability to quickly and accurately predict a variety of responses to acoustically energized skin panels with mounted components. Favorable comparisons between the measured and predicted responses were established. The validated models were used to examine vibration response sensitivities to relevant modeling parameters such as pressure patch density, mesh density, weight of the mounted component and model form. Convergence metrics include spectral densities and cumulative root-mean squared (RMS) functions for acceleration, velocity, displacement, strain and interface force. Minimum frequencies for response convergence were established as well as recommendations for modeling techniques, particularly in the early stages of a component design when accurate structural vibration requirements are needed relatively quickly. The results were compared with long-established guidelines for modeling accuracy of component-loaded panels. A theoretical basis for the Response/Pressure Transfer Function (RPTF) approach provides insight into trends observed in the response predictions and confirmed in the test data. The software developed for the RPTF method allows easy replacement of the diffuse acoustic field with other pressure fields such as a turbulent boundary layer (TBL) model suitable for vehicle ascent. Structural responses

  11. Responses of physiological and biochemical components in Gossypium hirsutum L. to mutagens

    International Nuclear Information System (INIS)

    Muthusamy, A.; Vasanth, K.; Jayabalan, N.

    2003-01-01

    The two tetraploid varieties of cotton were exposed to gamma rays, EMS and SA. Chlorophyll, carotenoids, sugar, starch, free amino acids, protein, lipids, DNA and RNA were estimated quantitatively. All the physiological and biochemical components were increased in lower dose/concentration of the mutagenic treatments and they were decreased in higher dose/concentrations. The stimulation of the biochemical contents was a dose/concentration dependent response. Among the two varieties, MCU 11 was found to be responsive to mutagens than MCU 5. Based on the study the lower dose/concentration of the mutagenic treatments could enhance the biochemical components which is used for improved economic characters of cotton. (author)

  12. Mathematical modelling of ultrasonic testing of components with defects close to a non-planar surface

    International Nuclear Information System (INIS)

    Westlund, Jonathan; Bostroem, Anders

    2011-05-01

    Nondestructive testing with ultrasound is a standard procedure in the nuclear power industry. To develop and qualify the methods extensive experimental work with test blocks is usually required. This can be very time-consuming and costly and it also requires a good physical intuition of the situation. A reliable mathematical model of the testing situation can, therefore, be very valuable and cost-effective as it can reduce experimental work significantly. A good mathematical model enhances the physical intuition and is very useful for parametric studies, as a pedagogical tool, and for the qualification of procedures and personnel. The aim of the present report is to describe work that has been performed to model ultrasonic testing of components that contain a defect close to a nonplanar surface. For nuclear power applications this may be a crack or other defect on the inside of a pipe with a diameter change or connection. This is an extension of the computer program UTDefect, which previously only admits a planar back surface (which is often applicable also to pipes if the pipe diameter is large enough). The problems are investigated in both 2D and 3D, and in 2D both the simpler anti-plane (SH) and the in-plane (P-SV) problem are studied. The 2D investigations are primarily solved to get a 'feeling' for the solution procedure, the discretizations, etc. In all cases an integral equation approach with a Green's function in the kernel is taken. The nonplanar surface is treated by the boundary element method (BEM) where a division of the surface is made in small elements. The defects are mainly cracks, strip-like (in 2D) or rectangular (in 3D), and these are treated with more analytical methods. In 2D also more general defects are treated with the help of their transition (T) matrix. As in other parts of UTDefect the ultrasonic probes in transmission and reception are included in the model. In 3D normalization by a side drilled hole is possible. Some numerical results

  13. PREDICTION OF SURFACE ROUGHNESS IN END MILLING OPERATION OF DUPLEX STAINLESS STEEL USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    S. D. PHILIP

    2015-03-01

    Full Text Available Response surface methodology has been used to study the effects of the machining parameters such as spindle speed, feed rate and axial depth of cut on surface roughness of duplex stainless steel in end milling operation. Dry milling experiments were conducted with three levels of spindle speed, feed rate and axial depth of cut. A mathematical model has been developed to predict the surface roughness in terms of the machining parameters using Box-Behnken design response surface methodology. The adequacy of the model was verified using analysis of variance. The prediction equation shows that the feed rate is the most important factor that influences the surface roughness followed by axial depth of cut and spindle speed. The validity of the model was verified by conducting the confirmation experiment.

  14. An atlas of monthly mean distributions of SSMI surface wind speed, ARGOS buoy drift, AVHRR/2 sea surface temperature, and ECMWF surface wind components during 1991

    Science.gov (United States)

    Halpern, D.; Knauss, W.; Brown, O.; Wentz, F.

    1993-01-01

    The following monthly mean global distributions for 1991 are presented with a common color scale and geographical map: 10-m height wind speed estimated from the Special Sensor Microwave Imager (SSMI) on a United States Air Force Defense Meteorological Satellite Program (DMSP) spacecraft; sea surface temperature estimated from the advanced very high resolution radiometer (AVHRR/2) on a U.S. National Oceanic and Atmospheric Administration (NOAA) spacecraft; Cartesian components of free-drifting buoys which are tracked by the ARGOS navigation system on NOAA satellites; and Cartesian components of the 10-m height wind vector computed by the European Center for Medium-Range Weather Forecasting (ECMWF). Charts of monthly mean value, sampling distribution, and standard deviation value are displayed. Annual mean distributions are displayed.

  15. An atlas of monthly mean distributions of SSMI surface wind speed, ARGOS buoy drift, AVHRR/2 sea surface temperature, and ECMWF surface wind components during 1990

    Science.gov (United States)

    Halpern, D.; Knauss, W.; Brown, O.; Wentz, F.

    1993-01-01

    The following monthly mean global distributions for 1990 are proposed with a common color scale and geographical map: 10-m height wind speed estimated from the Special Sensor Microwave Imager (SSMI) on a United States (US) Air Force Defense Meteorological Satellite Program (DMSP) spacecraft; sea surface temperature estimated from the advanced very high resolution radiometer (AVHRR/2) on a U.S. National Oceanic and Atmospheric Administration (NOAA) spacecraft; Cartesian components of free drifting buoys which are tracked by the ARGOS navigation system on NOAA satellites; and Cartesian components on the 10-m height wind vector computed by the European Center for Medium-Range Weather Forecasting (ECMWF). Charts of monthly mean value, sampling distribution, and standard deviation values are displayed. Annual mean distributions are displayed.

  16. Linear response theory of activated surface diffusion with interacting adsorbates

    Energy Technology Data Exchange (ETDEWEB)

    Marti' nez-Casado, R. [Department of Chemistry, Imperial College London, South Kensington, London SW7 2AZ (United Kingdom); Sanz, A.S.; Vega, J.L. [Instituto de Fi' sica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 123, 28006 Madrid (Spain); Rojas-Lorenzo, G. [Instituto Superior de Tecnologi' as y Ciencias Aplicadas, Ave. Salvador Allende, esq. Luaces, 10400 La Habana (Cuba); Instituto de Fi' sica Fundamental, Consejo Superior de Investigaciones Cienti' ficas, Serrano 123, 28006 Madrid (Spain); Miret-Artes, S., E-mail: s.miret@imaff.cfmac.csic.es [Instituto de Fi' sica Fundamental, Consejo Superior de Investigaciones Cienti' ficas, Serrano 123, 28006 Madrid (Spain)

    2010-05-12

    Graphical abstract: Activated surface diffusion with interacting adsorbates is analyzed within the Linear Response Theory framework. The so-called interacting single adsorbate model is justified by means of a two-bath model, where one harmonic bath takes into account the interaction with the surface phonons, while the other one describes the surface coverage, this leading to defining a collisional friction. Here, the corresponding theory is applied to simple systems, such as diffusion on flat surfaces and the frustrated translational motion in a harmonic potential. Classical and quantum closed formulas are obtained. Furthermore, a more realistic problem, such as atomic Na diffusion on the corrugated Cu(0 0 1) surface, is presented and discussed within the classical context as well as within the framework of Kramer's theory. Quantum corrections to the classical results are also analyzed and discussed. - Abstract: Activated surface diffusion with interacting adsorbates is analyzed within the Linear Response Theory framework. The so-called interacting single adsorbate model is justified by means of a two-bath model, where one harmonic bath takes into account the interaction with the surface phonons, while the other one describes the surface coverage, this leading to defining a collisional friction. Here, the corresponding theory is applied to simple systems, such as diffusion on flat surfaces and the frustrated translational motion in a harmonic potential. Classical and quantum closed formulas are obtained. Furthermore, a more realistic problem, such as atomic Na diffusion on the corrugated Cu(0 0 1) surface, is presented and discussed within the classical context as well as within the framework of Kramer's theory. Quantum corrections to the classical results are also analyzed and discussed.

  17. Assessment of Response Surface Models using Independent Confirmation Point Analysis

    Science.gov (United States)

    DeLoach, Richard

    2010-01-01

    This paper highlights various advantages that confirmation-point residuals have over conventional model design-point residuals in assessing the adequacy of a response surface model fitted by regression techniques to a sample of experimental data. Particular advantages are highlighted for the case of design matrices that may be ill-conditioned for a given sample of data. The impact of both aleatory and epistemological uncertainty in response model adequacy assessments is considered.

  18. Dopamine reward prediction-error signalling: a two-component response

    Science.gov (United States)

    Schultz, Wolfram

    2017-01-01

    Environmental stimuli and objects, including rewards, are often processed sequentially in the brain. Recent work suggests that the phasic dopamine reward prediction-error response follows a similar sequential pattern. An initial brief, unselective and highly sensitive increase in activity unspecifically detects a wide range of environmental stimuli, then quickly evolves into the main response component, which reflects subjective reward value and utility. This temporal evolution allows the dopamine reward prediction-error signal to optimally combine speed and accuracy. PMID:26865020

  19. A novel two-component system involved in secretion stress response in Streptomyces lividans.

    Directory of Open Access Journals (Sweden)

    Sonia Gullón

    Full Text Available BACKGROUND: Misfolded proteins accumulating outside the bacterial cytoplasmic membrane can interfere with the secretory machinery, hence the existence of quality factors to eliminate these misfolded proteins is of capital importance in bacteria that are efficient producers of secretory proteins. These bacteria normally use a specific two-component system to respond to the stress produced by the accumulation of the misfolded proteins, by activating the expression of HtrA-like proteases to specifically eliminate the incorrectly folded proteins. METHODOLOGY/PRINCIPAL FINDINGS: Overproduction of alpha-amylase in S. lividans causing secretion stress permitted the identification of a two-component system (SCO4156-SCO4155 that regulates three HtrA-like proteases which appear to be involved in secretion stress response. Mutants in each of the genes forming part of the two-genes operon that encodes the sensor and regulator protein components accumulated misfolded proteins outside the cell, strongly suggesting the involvement of this two-component system in the S. lividans secretion stress response. CONCLUSIONS/SIGNIFICANCE: To our knowledge this is the first time that a specific secretion stress response two-component system is found to control the expression of three HtrA-like protease genes in S. lividans, a bacterium that has been repeatedly used as a host for the synthesis of homologous and heterologous secretory proteins of industrial application.

  20. The Separation of Blood Components Using Standing Surface Acoustic Waves (SSAWs Microfluidic Devices: Analysis and Simulation

    Directory of Open Access Journals (Sweden)

    Ahmed M. Soliman

    2017-03-01

    Full Text Available The separation of blood components (WBCs, RBCs, and platelets is important for medical applications. Recently, standing surface acoustic wave (SSAW microfluidic devices are used for the separation of particles. In this paper, the design analysis of SSAW microfluidics is presented. Also, the analysis of SSAW force with Rayleigh angle effect and its attenuation in liquid-loaded substrate, viscous drag force, hydrodynamic force, and diffusion force are explained and analyzed. The analyses are provided for selecting the piezoelectric material, width of the main microchannel, working area of SAW, wavelength, minimum input power required for the separation process, and widths of outlet collecting microchannels. The design analysis of SSAW microfluidics is provided for determining the minimum input power required for the separation process with appropriated the displacement contrast of the particles.The analyses are applied for simulation the separation of blood components. The piezoelectric material, width of the main microchannel, working area of SAW, wavelength, and minimum input power required for the separation process are selected as LiNbO3, 120 μm, 1.08 mm2, 300 μm, 371 mW. The results are compared to other published results. The results of these simulations achieve minimum power consumption, less complicated setup, and high collecting efficiency. All simulation programs are built by MATLAB.

  1. Antibacterial performance of polypropylene nonwoven fabric wound dressing surfaces containing passive and active components

    Energy Technology Data Exchange (ETDEWEB)

    Xin, Zhirong, E-mail: xinzhirong2012@126.com [School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005 (China); Du, Shanshan; Zhao, Chunyu; Chen, Hao; Sun, Miao [School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005 (China); Yan, Shunjie [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Luan, Shifang, E-mail: sfluan@ciac.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Yin, Jinghua [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2016-03-01

    Graphical abstract: - Highlights: • PNVP and PHMG components were covalently immobilized on PP{sub NWF} surface. • PP{sub NWF}-g-PNVP-PHMG possessed bacterial adhesion-resistant and bactericidal capabilities. • PP{sub NWF}-g-PNVP-PHMG obviously suppressed platelet and red blood cell adhesion. - Abstract: A growing number of wound dressing-related nosocomial infections necessitate the development of novel antibacterial strategies. Herein, polypropylene non-woven fabric (PP{sub NWF}) was facilely modified with passive and active antibacterial components, namely photografting polymerization both N-Vinyl-2-pyrrolidone (NVP) and glycidyl methacrylate (GMA) monomers, and the introduction of guanidine polymer through the reaction between active amino groups and epoxy groups. The modified samples were confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), respectively. Water contact angle measurement, antibacterial test, platelet and red blood cell adhesion were used to evaluate the hydrophilicity, antibacterial properties and hemocompatibility of the samples. It was found that the antibacterial properties were obviously enhanced, meanwhile significantly suppressing platelet and red blood cell adhesion after the above modification. This PP{sub NWF} samples that possess antifouling and antimicrobial properties, have great potential in wound dressing applications.

  2. Antibacterial performance of polypropylene nonwoven fabric wound dressing surfaces containing passive and active components

    International Nuclear Information System (INIS)

    Xin, Zhirong; Du, Shanshan; Zhao, Chunyu; Chen, Hao; Sun, Miao; Yan, Shunjie; Luan, Shifang; Yin, Jinghua

    2016-01-01

    Graphical abstract: - Highlights: • PNVP and PHMG components were covalently immobilized on PP NWF surface. • PP NWF -g-PNVP-PHMG possessed bacterial adhesion-resistant and bactericidal capabilities. • PP NWF -g-PNVP-PHMG obviously suppressed platelet and red blood cell adhesion. - Abstract: A growing number of wound dressing-related nosocomial infections necessitate the development of novel antibacterial strategies. Herein, polypropylene non-woven fabric (PP NWF ) was facilely modified with passive and active antibacterial components, namely photografting polymerization both N-Vinyl-2-pyrrolidone (NVP) and glycidyl methacrylate (GMA) monomers, and the introduction of guanidine polymer through the reaction between active amino groups and epoxy groups. The modified samples were confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), respectively. Water contact angle measurement, antibacterial test, platelet and red blood cell adhesion were used to evaluate the hydrophilicity, antibacterial properties and hemocompatibility of the samples. It was found that the antibacterial properties were obviously enhanced, meanwhile significantly suppressing platelet and red blood cell adhesion after the above modification. This PP NWF samples that possess antifouling and antimicrobial properties, have great potential in wound dressing applications.

  3. A Krebs Cycle Component Limits Caspase Activation Rate through Mitochondrial Surface Restriction of CRL Activation.

    Science.gov (United States)

    Aram, Lior; Braun, Tslil; Braverman, Carmel; Kaplan, Yosef; Ravid, Liat; Levin-Zaidman, Smadar; Arama, Eli

    2016-04-04

    How cells avoid excessive caspase activity and unwanted cell death during apoptotic caspase-mediated removal of large cellular structures is poorly understood. We investigate caspase-mediated extrusion of spermatid cytoplasmic contents in Drosophila during spermatid individualization. We show that a Krebs cycle component, the ATP-specific form of the succinyl-CoA synthetase β subunit (A-Sβ), binds to and activates the Cullin-3-based ubiquitin ligase (CRL3) complex required for caspase activation in spermatids. In vitro and in vivo evidence suggests that this interaction occurs on the mitochondrial surface, thereby limiting the source of CRL3 complex activation to the vicinity of this organelle and reducing the potential rate of caspase activation by at least 60%. Domain swapping between A-Sβ and the GTP-specific SCSβ (G-Sβ), which functions redundantly in the Krebs cycle, show that the metabolic and structural roles of A-Sβ in spermatids can be uncoupled, highlighting a moonlighting function of this Krebs cycle component in CRL activation. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Detection of explosives on the surface of banknotes by Raman hyperspectral imaging and independent component analysis.

    Science.gov (United States)

    Almeida, Mariana R; Correa, Deleon N; Zacca, Jorge J; Logrado, Lucio Paulo Lima; Poppi, Ronei J

    2015-02-20

    The aim of this study was to develop a methodology using Raman hyperspectral imaging and chemometric methods for identification of pre- and post-blast explosive residues on banknote surfaces. The explosives studied were of military, commercial and propellant uses. After the acquisition of the hyperspectral imaging, independent component analysis (ICA) was applied to extract the pure spectra and the distribution of the corresponding image constituents. The performance of the methodology was evaluated by the explained variance and the lack of fit of the models, by comparing the ICA recovered spectra with the reference spectra using correlation coefficients and by the presence of rotational ambiguity in the ICA solutions. The methodology was applied to forensic samples to solve an automated teller machine explosion case. Independent component analysis proved to be a suitable method of resolving curves, achieving equivalent performance with the multivariate curve resolution with alternating least squares (MCR-ALS) method. At low concentrations, MCR-ALS presents some limitations, as it did not provide the correct solution. The detection limit of the methodology presented in this study was 50 μg cm(-2). Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Application of response surface methodology optimization for the ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-20

    Apr 20, 2009 ... of CQAs in tobacco waste were identified as three isomers containing chlorogenic acid (5-caffecylquinic acid ... Key words: Caffeic acid, caffeoylquinic acids (CQAs), hydrolysis reaction parameter optimization, response surface ..... Rosmarinic acid and caffeic acid produce antidepressive-like effect in.

  6. Response Surface Methodology's Steepest Ascent and Step Size Revisited

    NARCIS (Netherlands)

    Kleijnen, J.P.C.; den Hertog, D.; Angun, M.E.

    2002-01-01

    Response Surface Methodology (RSM) searches for the input combination maximizing the output of a real system or its simulation.RSM is a heuristic that locally fits first-order polynomials, and estimates the corresponding steepest ascent (SA) paths.However, SA is scale-dependent; and its step size is

  7. Response Surface Model Building Using Orthogonal Arrays for Computer Experiments

    Science.gov (United States)

    Unal, Resit; Braun, Robert D.; Moore, Arlene A.; Lepsch, Roger A.

    1997-01-01

    This study investigates response surface methods for computer experiments and discusses some of the approaches available. Orthogonal arrays constructed for computer experiments are studied and an example application to a technology selection and optimization study for a reusable launch vehicle is presented.

  8. On the Segmentation of the Response Surfaces for Super ...

    African Journals Online (AJOL)

    The Solutions of Linear and Quadratic Programming Problems using Super Convergent Line Series involving the Segmentation of the Response Surface are presented in the paper. It is verified that the number of segments, S for which optimal solutions of these problems selected for verification are obtained are 2 and 4 for ...

  9. Application of Response Surface Methodology for Optimizing Oil ...

    African Journals Online (AJOL)

    This study investigated the optimum processing conditions which give the maximum yield of oil extracted from tropical almond seed by the use of response surface methodology (RSM). The factors investigated were solvent concentration (50 – 100% v/v), extraction temperature (84 -100oC) and processing time (60 – 120 ...

  10. The utilization of the response surface methodology for the ...

    African Journals Online (AJOL)

    SERVER

    2007-12-03

    Dec 3, 2007 ... Drojdiile ca aliment-medicament. In: Anghel I (ed). Biologia si Tehnologia Drojdiilor, vol 2, Editura Tehnica, Bucharest. Shieh CJ, Liao HF, Lee CC (2003). Optimization of lipase-catalyzed biodiesel by response surface methodology, Bioresour. Technol. 88: 103-106. Smigelschi O, Woinarovschy A (1978).

  11. Application of response surface methodology optimization for the ...

    African Journals Online (AJOL)

    by HPLC-PAD-ESI-MS/MS, and used as raw material for producing CA which preparation process was optimized by response surface methodology (RSM). The research results indicated the main ingredients of CQAs in tobacco waste were identified as three isomers containing chlorogenic acid (5-caffecylquinic acid, ...

  12. The utilization of the response surface methodology for the ...

    African Journals Online (AJOL)

    A mutant strain of the yeast Saccharomyces cerevisiae growing on ethanol as single source of carbon and energy was used in optimization experiments at laboratory and micropilot scale, following the surface response methodology. The cultivation medium optimization was performed on the basis of maximization of dry cell ...

  13. Groundnut-Corn Starch Blend- A Response Surface Analysis

    African Journals Online (AJOL)

    Cookie bars were produced from mixtures of cassava and groundnut flours with cornstarch as binder. Box-Behnken response surface design for k=3 was used to study the effects of experimental variables for cassava flour (25-75%), groundnut flour (25-75%) and corn starch (5-15%). Effects of the experimental variables on ...

  14. Response surface method to optimize the low cost medium for ...

    African Journals Online (AJOL)

    A protease producing Bacillus sp. GA CAS10 was isolated from ascidian Phallusia arabica, Tuticorin, Southeast coast of India. Response surface methodology was employed for the optimization of different nutritional and physical factors for the production of protease. Plackett-Burman method was applied to identify ...

  15. Light Responsive Two-Component Supramolecular Hydrogel: A Sensitive Platform for Humidity Sensors

    KAUST Repository

    Samai, Suman

    2016-02-15

    The supramolecular assembly of anionic azobenzene dicarboxylate and cationic cetyltrimethylammonium bromide (CTAB) formed a stimuli responsive hydrogel with a critical gelation concentration (CGC) of 0.33 wt%. This self-sustainable two-component system was able to repair damage upon light irradiation. Moreover, it was successfully employed in the fabrication of highly sensitive humidity sensors for the first time.

  16. Optical response of the copper surface to carbon monoxide deposition.

    Science.gov (United States)

    Monachesi, P; Chiodo, L

    2004-09-10

    The optical response of the Cu surface upon CO deposition is investigated from the clean Cu(110) to the reconstructed CO/Cu(110)-p(2x1) geometry through ab initio electronic structure calculations. We ascribe the relevant structures in the calculated reflectance anisotropy spectrum of the reconstructed phase to the persistence of surface states transitions. These are excited by light polarized along the direction perpendicular to the one found at the clean surface. We devise a simple model for the evolution of the optical response in the adsorption process, identifying three different regimes. The impurity regime, at very low coverages, is characterized by a critical coverage that enhances the actual one by a factor of approximately 30, close to the value estimated experimentally.

  17. Response-Surface Methods in R, Using rsm

    Directory of Open Access Journals (Sweden)

    Russell V. Lenth

    2009-10-01

    Full Text Available This article describes the recent package rsm, which was designed to provide R support for standard response-surface methods. Functions are provided to generate central-composite and Box-Behnken designs. For analysis of the resulting data, the package provides for estimating the response surface, testing its lack of fit, displaying an ensemble of contour plots of the fitted surface, and doing follow-up analyses such as steepest ascent, canonical analysis, and ridge analysis. It also implements a coded-data structure to aid in this essential aspect of the methodology. The functions are designed in hopes of providing an intuitive and effective user interface. Potential exists for expanding the package in a variety of ways.

  18. Eddy current technique for detecting and sizing surface cracks in steel components

    International Nuclear Information System (INIS)

    Cecco, V.S.; Carter, J.R.; Sullivan, S.P.

    1995-01-01

    Cracking has occurred in pressure vessel nozzles and girth welds due to thermal fatigue. Pipe welds, welds in support structures, and welds in reactor vault liner panels in nuclear facilities have failed because of cracks. Cracking can also occur in turbine rotor bore surfaces due to high cycle fatigue. Dye penetrant, magnetic particle and other surface NDT methods are used to detect cracks but cannot be used for depth sizing. Crack depth can be measured with various NDT methods such as ultrasonic time-of-flight diffraction (TOFD), potential drop, and eddy current. The TOFD technique can be difficult to implement on nozzle welds and is best suited for sizing deep cracks (>5 mm). The conventional eddy current method is easy to implement, but crack sizing is normally limited to shallow cracks ( 2 mm) cracks. Eddy current testing (ET) techniques are readily amenable to remote/automatic inspections. These new probes could augment present magnetic particle (MT) and dye penetrant (PT) testing through provision of reliable defect depth information. Reliable crack sizing permits identification of critical cracks for plant life extension and licensing purposes. In addition, performing PT and MT generates low level radioactive waste in some inspection applications in nuclear facilities. Replacing these techniques with ET for some components will eliminate some of this radioactive waste. (author)

  19. Stress hormone release is a key component of the metabolic response to lipopolysaccharide (LPS)

    DEFF Research Database (Denmark)

    Bach, Ermina; Møller, Andreas Buch; Jorgensen, Jens Otto L

    2016-01-01

    on glucose, protein and lipid metabolism in eight HP and eight matched CTR twice during 4-h basal and 2-h hyperinsulinemic euglycemic clamp conditions with muscle biopsies and fat biopsies in each period during infusion with saline or LPS. RESULTS: LPS increased cortisol and growth hormone (GH) levels in CTR...... of stress hormones. We compared the metabolic effects of LPS in hypopituitary patients (HP) (in the absence of pituitary stress hormone responses) and healthy control subjects (CTR) (with normal pituitary stress hormone responses). DESIGN: Single blind randomized. METHODS: We compared effects of LPS...... pituitary function and appropriate cortisol and GH release are crucial components of the metabolic response to LPS....

  20. Exploration on Kerf-angle and Surface Roughness in Abrasive Waterjet Machining using Response Surface Method

    Science.gov (United States)

    Babu, Munuswamy Naresh; Muthukrishnan, Nambi

    2017-05-01

    Abrasive waterjet machining is a mechanical based unconventional cutting process which uses a mixture of abrasives and pressurized water as an intermediate to cut the material. The present paper focuses in analyzing the effect process parameters like feed rate, water pressure, standoff distance and abrasive flow rate on the surface roughness and kerf-angle of AISI 1018 mild steel experimentally. The experiments were performed under Taguchi's L27 orthogonal array. Moreover, the optimal parameter that significantly reduces the surface roughness and kerf-angle were calculated through response surface method. The most dominating process parameter that affects the responses was calculated by the Analysis of variance. In addition, machined surfaces are further subjected to scanning electron microscope (SEM) and atomic force microscope (AFM) for detailed study on the texture developed.

  1. Detecting geothermal anomalies and evaluating LST geothermal component by combining thermal remote sensing time series and land surface model data

    NARCIS (Netherlands)

    Romaguera, M.; Vaughan, R. G.; Ettema, J.; Izquierdo-Verdiguier, E.; Hecker, C. A.; van der Meer, F. D.

    2017-01-01

    This paper explores for the first time the possibilities to use two land surface temperature (LST) time series of different origins (geostationary Meteosat Second Generation satellite data and Noah land surface modelling, LSM), to detect geothermal anomalies and extract the geothermal component of

  2. Cell response to hydroxyapatite surface topography modulated by sintering temperature.

    Science.gov (United States)

    Mealy, Jacob; O'Kelly, Kevin

    2015-11-01

    Increased mesenchymal stem cell (MSC) activity on hydroxyapatite (HA) bone tissue engineering scaffolds will improve their viability in diffusion-based in vivo environments and is therefore highly desirable. This work focused on modulating the sintered HA surface topography with a view to increasing cell activity; this was achieved by varying the sintering temperature of the HA substrates. Cells were cultured on the substrates for periods of up to 19 days and displayed a huge variation in viability. MSC metabolic activity was measured using a resazurin sodium salt assay and revealed that surfaces sintered from 1250 to 1350°C significantly outperformed their lower temperature counterparts from day one (p ≤ 0.05). Surfaces sintered at 1300°C induced 57% more cell activity than the control at day 16. No significant activity was observed on surfaces sintered below 1200°C. It is suggested that this is due to the granular morphology produced at these temperatures providing insufficient contact area for cell attachment. In addition, we propose the average surface wavelength as a more quantitative surface descriptor than those readily found in the literature. The wavelengths of the substrates presented here were highly correlated with cell activity (R(2)  = 0.9019); with a wavelength of 2.675 µm on the 1300°C surface inducing the highest cell response. © 2015 Wiley Periodicals, Inc.

  3. Evaluation of electro-oxidation of biologically treated landfill leachate using response surface methodology

    International Nuclear Information System (INIS)

    Zhang Hui; Ran Xiaoni; Wu Xiaogang; Zhang Daobin

    2011-01-01

    Box-Behnken statistical experiment design and response surface methodology were used to investigate electrochemical oxidation of mature landfill leachate pretreated by sequencing batch reactor (SBR). Titanium coated with ruthenium dioxide (RuO 2 ) and iridium dioxide (IrO 2 ) was used as the anode in this study. The variables included current density, inter-electrode gap and reaction time. Response factors were ammonia nitrogen removal efficiency and COD removal efficiency. The response surface methodology models were derived based on the results. The predicted values calculated with the model equations were very close to the experimental values and the models were highly significant. The organic components before and after electrochemical oxidation were determined by GC-MS.

  4. Effect of Surface Nanotopography on Bone Response to Titanium Implant.

    Science.gov (United States)

    Freitas, Gileade P; Lopes, Helena B; Martins-Neto, Evandro C; de Oliveira, Paulo T; Beloti, Marcio M; Rosa, Adalberto L

    2016-06-01

    Clinical success of implant therapy is directly related to titanium (Ti) surface properties and the quality of bone tissue. The treatment of Ti implants with H2SO4/H2O2 is a feasible, reproducible, and low-cost technique to create surface nanotopography (Ti-Nano). As this nanotopography induces osteoblast differentiation, we hypothesized that it may affect bone response to Ti. Thus, this study was designed to evaluate the bone response to a machined Ti implant treated with H2SO4/H2O2 to generate Ti-Nano and to compare it with a commercially available microtopographic Ti implant (Ti-Porous). Implants were placed in rabbit tibias and evaluated after 2 and 6 weeks, and the bone tissue formed around them was assessed by microtomography to record bone volume, bone surface, specific bone surface, trabecular number, trabecular thickness, and trabecular separation. Undecalcified histological sections were used to determine the percentages of bone-to-implant contact, bone area formed between threads, and bone area formed in the mirror area. At the end of 6 weeks, the removal torque was evaluated using a digital torque gauge. The results showed bone formation in close contact with both Ti-Nano and Ti-Porous implants without relevant morphological and morphometric differences, in addition to a similar removal torque irrespective of surface topography. In conclusion, our results have shown that a simple and low-cost method using H2SO4/H2O2 is highly efficient for creating nanotopography on Ti surfaces, which elicits a similar bone response compared with microtopography presented in a commercially available Ti implant.

  5. Counterbalancing Regulation in Response Memory of a Positively Autoregulated Two-Component System.

    Science.gov (United States)

    Gao, Rong; Godfrey, Katherine A; Sufian, Mahir A; Stock, Ann M

    2017-09-15

    Fluctuations in nutrient availability often result in recurrent exposures to the same stimulus conditions. The ability to memorize the past event and use the "memory" to make adjustments to current behaviors can lead to a more efficient adaptation to the recurring stimulus. A short-term phenotypic memory can be conferred via carryover of the response proteins to facilitate the recurrent response, but the additional accumulation of response proteins can lead to a deviation from response homeostasis. We used the Escherichia coli PhoB/PhoR two-component system (TCS) as a model system to study how cells cope with the recurrence of environmental phosphate (Pi) starvation conditions. We discovered that "memory" of prior Pi starvation can exert distinct effects through two regulatory pathways, the TCS signaling pathway and the stress response pathway. Although carryover of TCS proteins can lead to higher initial levels of transcription factor PhoB and a faster initial response in prestarved cells than in cells not starved, the response enhancement can be overcome by an earlier and greater repression of promoter activity in prestarved cells due to the memory of the stress response. The repression counterbalances the carryover of the response proteins, leading to a homeostatic response whether or not cells are prestimulated. A computational model based on sigma factor competition was developed to understand the memory of stress response and to predict the homeostasis of other PhoB-regulated response proteins. Our insight into the history-dependent PhoBR response may provide a general understanding of how TCSs respond to recurring stimuli and adapt to fluctuating environmental conditions. IMPORTANCE Bacterial cells in their natural environments experience scenarios that are far more complex than are typically replicated in laboratory experiments. The architectures of signaling systems and the integration of multiple adaptive pathways have evolved to deal with such complexity

  6. Response surface optimisation for activation of bentonite with microwave irradiation

    Directory of Open Access Journals (Sweden)

    Rožić Ljiljana S.

    2011-01-01

    Full Text Available In this study, the statistical design of the experimental method was applied on the acid activation process of bentonite with microwave irradiation. The influence of activation parameters (time, acid normality and microwave heating power on the selected process response of the activated bentonite samples was studied. The specific surface area was chosen for the process response, because the chemical, surface and structural properties of the activated clay determine and limit its potential applications. The relationship of various process parameters with the specific surface area of bentonite was examined. A mathematical model was developed using a second-order response surface model (RSM with a central composite design incorporating the above mentioned process parameters. The mathematical model developed helped in predicting the variation in specific surface area of activated bentonite with time (5-21 min, acid normality (2-7 N and microwave heating power (63-172 W. The calculated regression models were found to be statistically significant at the required range and presented little variability. Furthermore, high values of R2 (0.957 and R2 (adjusted (0.914 indicate a high dependence and correlation between the observed and the predicted values of the response. These high values also indicate that about 96% of the result of the total variation can be explained by this model. In addition, the model shows that increasing the time and acid normality improves the textural properties of bentonites, resulting in increased specific surface area. This model also can be useful for setting an optimum value of the activation parameters for achieving the maximum specific surface area. An optimum specific surface area of 142 m2g-1 was achieved with an acid normality of 5.2 N, activation time of 7.38 min and microwave power of 117 W. Acid activation of bentonite was found to occur faster with microwave irradiation than with conventional heating. Microwave

  7. Questionnaire: involved actors in large disused components management - Summary Of Responses To The Questionnaire

    International Nuclear Information System (INIS)

    2012-01-01

    The aim of the Questionnaire is to establish an overview of the various bodies [Actors] that have responsibilities or input to the issue of large component decommissioning. In answering the intent is to cover the overall organisation and those bits that have most relevance to large components. The answers should reflect the areas from site operations to decommissioning as well as the wider issue of disposal at another location. The Questionnaire covers the following points: 1 - What is the country (institutional) structure for decommissioning? 2 - who does what and where lie the responsibilities? 3 - Which bodies have responsibility for onsite safety regulation, discharges and disposal? 4 - Which body(s) owns the facilities? 5 - Describe the responsibilities for funding of the decommissioning plan and disposal plan. Are they one and the same body? Whilst there are differences between countries there are some common threads. Regulation is through the state though the number of regulators involved may vary. In summary, the IAEA principles concerning independence of the regulatory body are followed. Funding arrangements vary but there are plans. Similarly, ownership of facilities is a mix of state and private. Some systems require a separate decommissioning license with Spain having the clearest demarcation of responsibilities for the decommissioning phase and waste management responsibilities

  8. Adherence of Helicobacter pylori cells and their surface components to HeLa cell membranes.

    Science.gov (United States)

    Fauchère, J L; Blaser, M J

    1990-12-01

    Four Helicobacter pylori strains were used to develop in vitro methods to assess adherence to HeLa cells. Using direct detection by microscopy, adhesion scores increased with the initial bacteria-to-cell ratio. The urease method assessed H. pylori bound to HeLa cells by their urease activity. The percentage of the original inoculum adhering to HeLa cells remained constant for initial ratios from 10(2) to 10(5) bacteria per cell. An ELISA using anti-H. pylori serum assessed whole bacteria or components bound to HeLa cell fractions. By all three methods, the four H. pylori strains were adherent to HeLa cells or membranes whereas Campylobacter fetus and Providencia control strains were not. The adherence of H. pylori whole cells decreased following extraction with saline, water, or glycine buffer and most of the superficial adhering material (SAM) was present in the saline or water extracts. SAM bound better to HeLa membranes than to calf fetuin or bovine serum albumin (BSA); binding was inhibited by preincubation of SAM with HeLa membranes but not with fetuin or BSA or by pretreatment of HeLa membranes with neuraminidase. These data indicate that SAM has a specific receptor on the HeLa cell membranes. By gel exclusion chromatography of bacterial extracts, the most adherent components were found in the fractions which also contained the highest urease activity; these fractions included urease subunit antigens. We conclude that adherence of H. pylori can be assessed by microtiter assays and involves bacterial surface material which co-purifies with urease and is different from the N-acetyl-neuraminyl-lactose binding hemagglutinin.

  9. Response of fuzzy tungsten surfaces to pulsed plasma bombardment

    International Nuclear Information System (INIS)

    Nishijima, D.; Doerner, R.P.; Iwamoto, D.; Kikuchi, Y.; Miyamoto, M.; Nagata, M.; Sakuma, I.; Shoda, K.; Ueda, Y.

    2013-01-01

    Damage of fuzzy tungsten surfaces due to a transient plasma load is characterized in terms of mass loss, surface morphology, and optical properties. A single D pulsed (∼0.1–0.2 ms) plasma shot with surface absorbed energy density of ∼1.1 MJ m −2 leads to a mass loss of ∼80 μg, which cannot be explained by physical sputtering. Thus, macroscopic erosion processes such as droplets and dust release as well as arcing are thought to be responsible for the mass loss. In fact, scanning electron microscopy observations reveal the melting of the tips of fuzz and arc tracks. The optical reflectivity of the damaged (melted) surface is measured to be higher than that of an undamaged fuzzy surface (below ∼0.01%). Spectroscopic ellipsometry shows that the refractive index, n, and extinction coefficient, k, increase from n ≈ 1 and k ≈ 0 for an undamaged fuzzy surface with an increase in the degree of damage of fuzz

  10. Numbers of center points appropriate to blocked response surface experiments

    Science.gov (United States)

    Holms, A. G.

    1979-01-01

    Tables are given for the numbers of center points to be used with blocked sequential designs of composite response surface experiments as used in empirical optimum seeking. The tables also give the star point radii for exact orthogonal blocking. The center point options vary from a lower limit of one to an upper limit equal to the numbers proposed by Box and Hunter for approximate rotatability and uniform variance, and exact orthogonal blocking. Some operating characteristics of the proposed options are described.

  11. Ceramic Surface Treatment with a Single-component Primer: Resin Adhesion to Glass Ceramics.

    Science.gov (United States)

    Prado, Mayara; Prochnow, Catina; Marchionatti, Ana Maria Estivalete; Baldissara, Paolo; Valandro, Luiz Felipe; Wandscher, Vinicius Felipe

    2018-04-19

    To evaluate the microshear bond strength (μSBS) of composite cement bonded to two machined glass ceramics and its durability, comparing conventional surface conditioning (hydrofluoric acid + silane) to a one-step primer (Monobond Etch & Prime). Machined slices of lithium disilicate ceramic (LDC) (IPS e.max CAD) and feldspathic ceramic (FC) (VITA Mark II) glass ceramics were divided into two groups (n = 10) according to two factors: 1. surface treatment: HF+S (ca 5% hydrofluoric acid [IPS Ceramic Etching GEL] + silane coupling agent [SIL; Monobond Plus]) or MEP (single-component ceramic conditioner; Monobond Etch & Prime); 2. storage condition: baseline (without aging; tested 24 h after cementing) or aged (70 days of water storage + 12,000 thermal cycles). Composite cement (Multilink Automix, Ivoclar Vivadent) was applied to starch matrices on the treated ceramic surfaces and photoactivated. A μSBS test was performed (0.5 mm/min) and the failure pattern was determined. Contact angle and micromorphological analyses were also performed. Data were analyzed with Student's t-test (α = 5%). For both ceramic materials, HF+S resulted in higher mean μSBS (MPa) at baseline (LDC: HF+S 21.2 ± 2.2 > MEP 10.4 ± 2.4; FC: HF+S 19.6 ± 4.3 > MEP 13.5 ± 5.4) and after aging (LDC: HF+S 14.64 ± 2.31 > MEP 9 ± 3.4; FC HF+S: 14.73 ± 3.33 > MEP 11.1 ± 3.3). HF+S resulted in a statistically significant decrease in mean μSBS after aging (p = 0.0001), while MEP yielded no significant reduction. The main failure type was adhesive between composite cement and ceramic. HF+S resuted in the lowest contact angle. Hydrofluoric acid + silane resulted in higher mean μSBS than Monobond Etch & Prime for both ceramics; however, Monobond Etch & Prime had stable bonding after aging.

  12. Plant surface wax affects parasitoid's response to host footprints

    Science.gov (United States)

    Rostás, Michael; Ruf, Daniel; Zabka, Vanessa; Hildebrandt, Ulrich

    2008-10-01

    The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants ( cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones.

  13. Two component silicone modified epoxy foul release coatings: Effect of modulus, surface energy and surface restructuring on pseudobarnacle and macrofouling behavior

    International Nuclear Information System (INIS)

    Rath, S.K.; Chavan, J.G.; Sasane, Savita; Jagannath; Patri, M.; Samui, A.B.; Chakraborty, B.C.

    2010-01-01

    Two component silicone modified epoxy resin based low surface energy and non-toxic foul release coatings were developed. Silicone modified epoxy resin with 15 and 30% silicone content was used as component A and a polyether diamine (Jeffamine-500) was used as the component B. Free standing films were prepared by casting a mixture of components A and B in stoichiometric proportions. The surface composition, surface topography and wetting properties of the coatings were studied by angle resolved X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and contact angle goniometry respectively. The mechanical properties of the cured films were evaluated by tensile measurements as well as dynamic mechanical analysis. Pseudobarnacles made of aluminium studs were attached to the coated panels and adhesion tests were carried out by a pseudobarnacle tester. Coated panels were exposed in Mumbai harbor for fouling studies for a period of 90 days. Surface restructuring studies of the coatings upon immersion in seawater were carried out by measuring the changes in advancing and receding contact angles by contact angle goniometry. The effect of surface energy, modulus and surface restructuring of the coatings on the macrofouling and pseudobarnacle adhesion properties has been discussed in detail.

  14. Factors Predicting the Ocular Surface Response to Desiccating Environmental Stress

    Science.gov (United States)

    Alex, Anastasia; Edwards, Austin; Hays, J. Daniel; Kerkstra, Michelle; Shih, Amanda; de Paiva, Cintia S.; Pflugfelder, Stephen C.

    2013-01-01

    Purpose. To identify factors predicting the ocular surface response to experimental desiccating stress. Methods. The ocular surfaces of both eyes of 15 normal and 10 dry eye subjects wearing goggles were exposed to a controlled desiccating environment (15%–25% relative humidity and 2–5 L/min airflow) for 90 minutes. Eye irritation symptoms, blink rate, tear meniscus dimensions, noninvasive (RBUT) and invasive tear break-up time, and corneal fluorescein and conjunctival lissamine green-dye staining were recorded before and after desiccating stress. Pre- and postexposure measurements were compared, and Pearson correlations between clinical parameters before and after desiccating stress were calculated. Results. Corneal and conjunctival dye staining significantly increased in all subjects following 90-minute exposure to desiccating environment, and the magnitude of change was similar in normal and dry eye subjects; except superior cornea staining was greater in dry eye. Irritation severity in the desiccating environment was associated with baseline dye staining, baseline tear meniscus height, and blink rate after 45 minutes. Desiccation-induced change in corneal fluorescein staining was inversely correlated to baseline tear meniscus width, whereas change in total ocular surface dye staining was inversely correlated to baseline dye staining, RBUT, and tear meniscus height and width. Blink rate from 30 to 90 minutes in desiccating environment was higher in the dry eye than normal group. Blink rate significantly correlated to baseline corneal fluorescein staining and environmental-induced change in corneal fluorescein staining. Conclusions. Ocular surface dye staining increases in response to desiccating stress. Baseline ocular surface dye staining, tear meniscus height, and blink rate predict severity of ocular surface dye staining following exposure to a desiccating environment. PMID:23572103

  15. Optimization and in vitro antiproliferation of Curcuma wenyujin's active extracts by ultrasonication and response surface methodology.

    Science.gov (United States)

    Wang, Xiaoqin; Jiang, Ying; Hu, Daode

    2016-01-01

    Curcuma wenyujin, a member of the genus Curcuma, has been widely prescribed for anti-cancer therapy. Multiple response surface optimization has attracted a great attention, while, the research about optimizing three or more responses employing response surface methodology (RSM) was very few. RSM and desirability function (DF) were employed to get the optimum ultrasonic extraction parameters, in which the extraction yields of curdione, furanodienone, curcumol and germacrone from C. wenyujin were maximum. The yields in the extract were accurately quantified using the validated high performance liquid chromatography method with a good precision and accuracy. The optimization results indicated that the maximum combined desirability 97.1 % was achieved at conditions as follows: liquid-solid ratio, 8 mL g(-1); ethanol concentration, 70 % and ultrasonic time, 20 min. The extraction yields gained from three verification experiments were in fine agreement with those of the model's predictions. The surface morphologies of the sonication-treated C. wenyujin were loose and rough. The extract of C. wenyujin presented obvious antiproliferative activities against RKO and HT-29 cells in vitro. Response surface methodology was successfully applied to model and optimize the ultrasonic extraction of four bioactive components from C. wenyujin for antiproliferative activitiy.Graphical abstract.

  16. Variance components and selection response for feather-pecking behavior in laying hens.

    Science.gov (United States)

    Su, G; Kjaer, J B; Sørensen, P

    2005-01-01

    Variance components and selection response for feather pecking behavior were studied by analyzing the data from a divergent selection experiment. An investigation indicated that a Box-Cox transformation with power lambda = -0.2 made the data approximately normally distributed and gave the best fit for the model. Variance components and selection response were estimated using Bayesian analysis with Gibbs sampling technique. The total variation was rather large for the investigated traits in both the low feather-pecking line (LP) and the high feather-pecking line (HP). Based on the mean of marginal posterior distribution, in the Box-Cox transformed scale, heritability for number of feather pecking bouts (FP bouts) was 0.174 in line LP and 0.139 in line HP. For number of feather-pecking pecks (FP pecks), heritability was 0.139 in line LP and 0.105 in line HP. No full-sib group effect and observation pen effect were found in the 2 traits. After 4 generations of selection, the total response for number of FP bouts in the transformed scale was 58 and 74% of the mean of the first generation in line LP and line HP, respectively. The total response for number of FP pecks was 47 and 46% of the mean of the first generation in line LP and line HP, respectively. The variance components and the realized selection response together suggest that genetic selection can be effective in minimizing FP behavior. This would be expected to reduce one of the major welfare problems in laying hens.

  17. The Influence of the Tool Surface Texture on Friction and the Surface Layers Properties of Formed Component

    Directory of Open Access Journals (Sweden)

    Jana Šugárová

    2018-03-01

    Full Text Available The morphological texturing of forming tool surfaces has high potential to reduce friction and tool wear and also has impact on the surface layers properties of formed material. In order to understand the effect of different types of tool textures, produced by nanosecond fibre laser, on the tribological conditions at the interface tool-formed material and on the integrity of formed part surface layers, the series of experimental investigations have been carried out. The coefficient of friction for different texture parameters (individual feature shape, including the depth profile of the cavities and orientation of the features relative to the material flow was evaluated via a Ring Test and the surface layers integrity of formed material (surface roughness and subsurface micro hardness was also experimentally analysed. The results showed a positive effect of surface texturing on the friction coefficients and the strain hardening of test samples material. Application of surface texture consisting of dimple-like depressions arranged in radial layout contributed to the most significant friction reduction of about 40%. On the other hand, this surface texture contributed to the increase of surface roughness parameters, Ra parameter increased from 0.49 μm to 2.19 μm and the Rz parameter increased from 0.99 μm to 16.79 μm.

  18. Theory of synergistic effects: Hill-type response surfaces as 'null-interaction' models for mixtures.

    Science.gov (United States)

    Schindler, Michael

    2017-08-02

    The classification of effects caused by mixtures of agents as synergistic, antagonistic or additive depends critically on the reference model of 'null interaction'. Two main approaches are currently in use, the Additive Dose (ADM) or concentration addition (CA) and the Multiplicative Survival (MSM) or independent action (IA) models. We compare several response surface models to a newly developed Hill response surface, obtained by solving a logistic partial differential equation (PDE). Assuming that a mixture of chemicals with individual Hill-type dose-response curves can be described by an n-dimensional logistic function, Hill's differential equation for pure agents is replaced by a PDE for mixtures whose solution provides Hill surfaces as 'null-interaction' models and relies neither on Bliss independence or Loewe additivity nor uses Chou's unified general theory. An n-dimensional logistic PDE decribing the Hill-type response of n-component mixtures is solved. Appropriate boundary conditions ensure the correct asymptotic behaviour. Mathematica 11 (Wolfram, Mathematica Version 11.0, 2016) is used for the mathematics and graphics presented in this article. The Hill response surface ansatz can be applied to mixtures of compounds with arbitrary Hill parameters. Restrictions which are required when deriving analytical expressions for response surfaces from other principles, are unnecessary. Many approaches based on Loewe additivity turn out be special cases of the Hill approach whose increased flexibility permits a better description of 'null-effect' responses. Missing sham-compliance of Bliss IA, known as Colby's model in agrochemistry, leads to incompatibility with the Hill surface ansatz. Examples of binary and ternary mixtures illustrate the differences between the approaches. For Hill-slopes close to one and doses below the half-maximum effect doses MSM (Colby, Bliss, Finney, Abbott) predicts synergistic effects where the Hill model indicates 'null

  19. Fabrication and application of responsive polymer surfaces on planar substrates and colloidal particles

    Science.gov (United States)

    Lupitskyy, Robert

    2009-11-01

    In the present dissertation, the problem of controlling interactions of material surfaces with the environment was addressed. Using chemical modification of surfaces with responsive polymers, it is possible to use external stimuli to regulate surface wettability, protein adsorption, stability, and interfacial properties of colloidal particles. The research work presented in this dissertation consists of four independent parts. In the first part (Chapter II), the responsive behavior of a novel heteroarm star-copolymer, poly(2-vinylpyridine)-star-poly(styrene) (PS7-P2VP7), was investigated. For grafted layers of PS7-P2VP7,surface composition, morphology, and wettability can be reversibly changed by treatment with solvents of different thermodynamic quality. Grafted layers of the star-copolymer exhibit a pronounced solvent-dependent phase segregation characteristic and behave similarly to mixed polymer brushes with incompatible components. In the second part (Chapter III), the regulation of fibrinogen adsorption by changing surface composition and microstructure of a mixed polymer brush was explored. The brush is a combination of a protein-repelling component, poly(ethylene glycol), and a protein-attracting component, poly(acrylic acid)-b-polystyrene. Treatment with different organic solvents changes the degree of adsorption of a test protein, fibrinogen, whereas treatment with calcium chloride solution results in virtually no protein adsorption at all. Studies of brush morphology and brush extension in aqueous medium revealed that treatment with different solvents results in different size and distribution of polystyrene domains, which in turn affects the adsorption of fibrinogen. In the third part (Chapter IV), a responsive colloidal system was developed by grafting poly(styrene-b-2-vinylpyridine-b-ethylene oxide) triblock copolymer onto the surface of 200 nm silica particles. This type of grafted polymer layer is both pH- and solvent-sensitive. These properties

  20. The effect of laser pulse width on laser-induced damage at K9 and UBK7 components surface

    Science.gov (United States)

    Zhou, Xinda; Ba, Rongsheng; Zheng, Yinbo; Yuan, Jing; Li, Wenhong; Chen, Bo

    2015-07-01

    In this paper, we investigated the effects of laser pulse width on laser-induced damage. We measured the damage threshold of K9 glass and UBK7 glass optical components at different pulse width, then analysis pulse-width dependence of damage threshold. It is shown that damage threshold at different pulse width conforms to thermal restriction mechanism, Because of cm size laser beam, defect on the optical component surface leads to laser-induced threshold decreased.

  1. Evaluation of the Cutting Force Components and the Surface Roughness in the Milling Process of Micro- and Nanocrystalline Titanium

    Directory of Open Access Journals (Sweden)

    Habrat W.

    2016-09-01

    Full Text Available Nanocristalline pure titanium in comparison to microcrystalline titanium is characterized by better mechanical properties which influence its wider usability. The aim of the research was to evaluate whether the grain size of pure titanium (micro- and nanocrystalline has influence on the cutting force components and the surface roughness in the milling process. Models of cutting force components for both materials were prepared and differences between the results were examined. The feed rate effect on selected parameters of surface roughness after milling of micro- and nanocrystalline pure titanium was determined.

  2. Molecular Components of the Sporothrix schenckii Complex that Induce Immune Response.

    Science.gov (United States)

    Alba-Fierro, Carlos A; Pérez-Torres, Armando; Toriello, Conchita; Romo-Lozano, Yolanda; López-Romero, Everardo; Ruiz-Baca, Estela

    2016-08-01

    Sporotrichosis is a fungal disease caused by the Sporothrix schenckii complex that includes species such as S. brasiliensis, S. schenckii sensu stricto, S. globosa, S. luriei, S. mexicana, and S. pallida, which exhibit different potentially antigenic molecular components. The immune response of susceptible hosts to control infection and disease caused by these fungi has been little studied. Besides, the fungus-host interaction induces the activation of different types of immune response. This mini-review analyzes and discusses existing reports on the identification and functional characterization of molecules from species of the S. schenckii complex with clinical relevance, and the mechanisms that mediate the type and magnitude of the immune response in experimental models in vivo and in vitro. This knowledge is expected to contribute to the development of protective and therapeutic strategies against sporotrichosis and other mycoses.

  3. Surface-Active Agents for Isolation of the Core Component of Avian Myeloblastosis Virus 1

    Science.gov (United States)

    Stromberg, Kurt

    1972-01-01

    Sixty-one surface-active agents were evaluated in a procedure designed to assess their ability to remove the envelope from the core component of avian myeloblastosis virus (AMV). The procedure consisted of centrifugation of intact AMV through a series of sucrose gradients each containing an upper layer of agent at one of eight concentrations between 0.01 and 10%. The effectiveness of an agent in producing AMV cores was indicated by (i) the appearance of light-scattering bands in the region of core buoyant density in gradient tubes; (ii) the range of surfactant concentration over which these bands appeared; and (iii) an electron microscopy assessment by the negative-staining technique of the relative proportion of core to non-core material in each of these bands. Six nonionic surfactants were selected by this screening method for comparison in regard to recovery of core protein and endogenous ribonucleic acid (RNA)-dependent deoxyribonucleic acid (DNA) polymerase activity, as well as further morphologic evaluation by electron microscopy. The nonionic surfactants of the polyoxyethylene alcohol class (particularly, Sterox SL) were most effective. Nonionic surfactants of the polyoxyethylene alkylphenol class (particularly, Nonidet P-40) were also effective. Sterox SL and Nonidet P-40 each gave a more than fivefold increase in specific activity of endogenous RNA-dependent DNA polymerase, and each gave a low recovery of core protein. Sterox SL did not interfere to the extent that Nonidet P-40 did in procedures which involved spectrophotometric assay at 260 nm. The use of Sterox SL resulted in the least envelope contamination of core preparations by electron microscopy examination, the most recovery of protein and endogenous RNA-dependent DNA polymerase activity, and a core buoyant density in sucrose of 1.27 g/ml. Images PMID:4112071

  4. 3D Printed Reversible Shape Changing Components with Stimuli Responsive Materials.

    Science.gov (United States)

    Mao, Yiqi; Ding, Zhen; Yuan, Chao; Ai, Shigang; Isakov, Michael; Wu, Jiangtao; Wang, Tiejun; Dunn, Martin L; Qi, H Jerry

    2016-04-25

    The creation of reversibly-actuating components that alter their shapes in a controllable manner in response to environmental stimuli is a grand challenge in active materials, structures, and robotics. Here we demonstrate a new reversible shape-changing component design concept enabled by 3D printing two stimuli responsive polymers-shape memory polymers and hydrogels-in prescribed 3D architectures. This approach uses the swelling of a hydrogel as the driving force for the shape change, and the temperature-dependent modulus of a shape memory polymer to regulate the time of such shape change. Controlling the temperature and aqueous environment allows switching between two stable configurations - the structures are relatively stiff and can carry load in each - without any mechanical loading and unloading. Specific shape changing scenarios, e.g., based on bending, or twisting in prescribed directions, are enabled via the controlled interplay between the active materials and the 3D printed architectures. The physical phenomena are complex and nonintuitive, and so to help understand the interplay of geometric, material, and environmental stimuli parameters we develop 3D nonlinear finite element models. Finally, we create several 2D and 3D shape changing components that demonstrate the role of key parameters and illustrate the broad application potential of the proposed approach.

  5. Specific IgE response to different grass pollen allergen components in children undergoing sublingual immunotherapy

    Directory of Open Access Journals (Sweden)

    Marcucci Francesco

    2012-06-01

    Full Text Available Abstract Background Grass pollen is a major cause of respiratory allergy worldwide and contain a number of allergens, some of theme (Phl p 1, Phl p 2, Phl p 5, and Phl 6 from Phleum pratense, and their homologous in other grasses are known as major allergens. The administration of grass pollen extracts by immunotherapy generally induces an initial rise in specific immunoglobulin E (sIgE production followed by a progressive decline during the treatment. Some studies reported that immunotherapy is able to induce a de novo sensitisation to allergen component previously unrecognized. Methods We investigated in 30 children (19 males and 11 females, mean age 11.3 years, 19 treated with sublingual immunotherapy (SLIT by a 5-grass extract and 11 untreated, the sIgE and sIgG4 response to the different allergen components. Results Significant increases (p  Conclusions These findings confirm that the initial phase of SLIT with a grass pollen extract enhances the sIgE synthesis and show that the sIgE response concerns the same allergen components which induce IgE reactivity during natural exposure.

  6. Damage identification in beams by a response surface based technique

    Directory of Open Access Journals (Sweden)

    Teidj S.

    2014-01-01

    Full Text Available In this work, identification of damage in uniform homogeneous metallic beams was considered through the propagation of non dispersive elastic torsional waves. The proposed damage detection procedure consisted of the following sequence. Giving a localized torque excitation, having the form of a short half-sine pulse, the first step was calculating the transient solution of the resulting torsional wave. This torque could be generated in practice by means of asymmetric laser irradiation of the beam surface. Then, a localized defect assumed to be characterized by an abrupt reduction of beam section area with a given height and extent was placed at a known location of the beam. Next, the response in terms of transverse section rotation rate was obtained for a point situated afterwards the defect, where the sensor was positioned. This last could utilize in practice the concept of laser vibrometry. A parametric study has been conducted after that by using a full factorial design of experiments table and numerical simulations based on a finite difference characteristic scheme. This has enabled the derivation of a response surface model that was shown to represent adequately the response of the system in terms of the following factors: defect extent and severity. The final step was performing the inverse problem solution in order to identify the defect characteristics by using measurement.

  7. Influence of surface-energy components of Ni-P-TiO2-PTFE nanocomposite coatings on bacterial adhesion.

    Science.gov (United States)

    Liu, Chen; Zhao, Qi

    2011-08-02

    The influence of total surface energy on bacterial adhesion has been investigated intensively with the frequent conclusion that bacterial adhesion is less on low-energy surfaces. However, there are also a number of contrary findings that high-energy surfaces have a smaller biofouling tendency. Recently, it was found that the CQ ratio, which is defined as the ratio of Lifshitz-van der Waals (LW) apolar to electron donor surface-energy components of substrates, has a strong correlation to bacterial adhesion. However, the electron donor surface-energy components of substrates varied over only a very limited range. In this article, a series of Ni-P-TiO(2)-PTFE nanocomposite coatings with wide range of surface-energy components were prepared using an electroless plating technique. The bacterial adhesion and removal on the coatings were evaluated with different bacteria under both static and flow conditions. The experimental results demonstrated that there was a strong correlation between bacterial attachment (or removal) and the CQ ratio. The coatings with the lowest CQ ratio had the lowest bacterial adhesion or the highest bacterial removal, which was explained using the extented DLVO theory.

  8. Process chain for fabrication of anisotropic optical functional surfaces on polymer components

    DEFF Research Database (Denmark)

    Li, Dongya; Zhang, Yang; Regi, Francesco

    2017-01-01

    This paper aims to introduce a process chain for fabrication of anisotropic optical functional surfaces on polymer products. Thesurface features under investigation are composed of micro serrated ridges. The scope was to maximize the visible contrast betweenhorizontally orthogonal textured surfaces...

  9. Surface roughness characterization of cast components using 3D optical methods

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Tiedje, Niels Skat; Hansen, Hans Nørgaard

    made in green sand moulds and the surface roughness parameter (Sa) values were compared with those of the standards. Sa parameter suffices for the evaluation of casting surface texture. The S series comparators showed a better description of the surface of castings after shot blasting than the A series...

  10. Effect of design selection on response surface performance

    Science.gov (United States)

    Carpenter, William C.

    1993-01-01

    Artificial neural nets and polynomial approximations were used to develop response surfaces for several test problems. Based on the number of functional evaluations required to build the approximations and the number of undetermined parameters associated with the approximations, the performance of the two types of approximations was found to be comparable. A rule of thumb is developed for determining the number of nodes to be used on a hidden layer of an artificial neural net and the number of designs needed to train an approximation is discussed.

  11. Fetal auditory responses to external sounds and mother's heart beat: detection improved by Independent Component Analysis.

    Science.gov (United States)

    Porcaro, Camillo; Zappasodi, Filippo; Barbati, Giulia; Salustri, Carlo; Pizzella, Vittorio; Rossini, Paolo Maria; Tecchio, Franca

    2006-07-26

    In this paper, we present a magnetoencephalographic study of the fetal auditory response to external stimuli and to the sound of the mother's heartbeat. We describe how an ad hoc functional selection procedure allowed us to isolate the sources in the fetal brain responding to sounds only, after the application to the recorded data of a standard Independent Component Analysis algorithm. In our experiment, acoustic stimuli were delivered to twelve healthy women with uncomplicated pregnancies at a time between 36 and 40 weeks gestational age, with their fetuses in breech presentation. Ultrasound images allowed determination of the region over the women's abdomen nearest to the fetal head, over which both the acoustic stimulator and the MEG sensors were subsequently placed. In 8 out of the 12 cases, our analysis provided consistent evidence of a fetal response both to the mother's heartbeat and to the external auditory stimulation; both were characterized by a clear prominent component at around 200 ms latency, which is widely accepted as the marker of the fetal response to auditory stimuli.

  12. Measurement of the surface morphology of plasma facing components on the EAST tokamak by a laser speckle interferometry approach

    Science.gov (United States)

    Hongbei, WANG; Xiaoqian, CUI; Yuanbo, LI; Mengge, ZHAO; Shuhua, LI; Guangnan, LUO; Hongbin, DING

    2018-03-01

    The laser speckle interferometry approach provides the possibility of an in situ optical non-contacted measurement for the surface morphology of plasma facing components (PFCs), and the reconstruction image of the PFC surface morphology is computed by a numerical model based on a phase unwrapping algorithm. A remote speckle interferometry measurement at a distance of three meters for real divertor tiles retired from EAST was carried out in the laboratory to simulate a real detection condition on EAST. The preliminary surface morphology of the divertor tiles was well reproduced by the reconstructed geometric image. The feasibility and reliability of this approach for the real-time measurement of PFCs have been demonstrated.

  13. Assessment of total equivalent strain at the surface of strain controlled axisymmetric components

    International Nuclear Information System (INIS)

    Green, D.; Smith, P.S.

    1987-01-01

    The ASME Boiler and Pressure Vessel Code Case N 47 (ASME) specifies rules for assessing fatigue and creep damage to components operating at elevated temperatures. Two routes are specified, namely an elastic route and an inelastic route. This paper considers the possibility of using this approach to thermally shocked components where primary loads are negligible. (orig./GL)

  14. IAEA consultants' meeting on thermal response of plasma facing materials and components

    International Nuclear Information System (INIS)

    Janev, R.K.

    1990-07-01

    The present Summary Report contains brief proceedings and the main conclusions and recommendations of the IAEA Consultants' Meeting on ''Thermal Response of Plasma Facing Materials and Components'', which was organized by the IAEA Atomic and Molecular Data Unit and held on June 11-13, 1990, in Vienna, Austria. The Report also includes a categorization and assessment of currently studied plasma facing materials, a classification scheme of material properties data, required in fusion reactor design, and a survey of the urgently needed material properties data. (author)

  15. Ionospheric convection response to changes of interplanetary magnetic field B-z component during strong B-y component

    DEFF Research Database (Denmark)

    Huang, C.S.; Murr, D.; Sofko, G.J.

    2000-01-01

    enough, the B-z reorientation causes changes in the flow intensity but not in the shape of the convection pattern. The results show the characteristics of ionospheric convection response during strong B-y and suggest that the convection reconfiguration is not only determined by the changing B-z but also...... the dawn-dusk meridian plane, which is interpreted as propagation or expansion of newly generated convection cells in the cusp region. Other studies showed that the change in convection pattern in response to IMF reorientations is spatially fixed. In this paper, we investigate the ionospheric convection...... response to IMF Bz changes during strong IMF BZ. On March 23, 1995, B-x was small, B-y was strongly positive (7-11 nT), and the B-z polarity changed several times after 1300 UT. The dayside ionospheric convection is dominated by a large clockwise convection cell. The cell focus (the "eye" of the convection...

  16. The antagonic effect of iron and zinc in formulations of feeding diets studied by response surface methodology for mixtures

    OpenAIRE

    BUENO, Luciana

    2008-01-01

    Nutritional therapy with enteral diets became substantially specialized over the last years. This work's aim was to study the effect of the components of a formulation: fiber, calcium and medium-chain triglycerides for dialysability of minerals. Analysis of multiple variables was carried out using response surface methodology. The level curve showed an antagonic effect of interaction between iron and zinc. TCM was the variable responsible for characterizing competition between the two mineral...

  17. Changes in contact angle providing evidence for surface alteration in multi-component solid foods

    Science.gov (United States)

    Reinke, Svenja K.; Hauf, Katharina; Vieira, Josélio; Heinrich, Stefan; Palzer, Stefan

    2015-11-01

    Chocolate blooming, one of the major problems in the confectionery industry, is the formation of visible white spots or a greyish haze on the surface of chocolate products due to large sugar or fat crystals on the surface. This leads to aesthetic changes and deterioration of taste and thus large sales losses for the confectionery industry due to consumer complaints. Chocolate blooming is often related to migration of lipids or sugar molecules to the chocolate surface, where they recrystallize with an associated polymorphic change of crystal structure on the surface. The wetting behaviour from contact angle measurements gives further insight into surface properties and is needed to determine surface energies and to evaluate possible migration mechanisms and preferred pathways. Therefore, an equilibrium contact angle is needed which is not directly accessible and is influenced by surface texture and interaction between solid and test liquid. In this study, the surface of cocoa butter and conventional chocolates was characterized by measuring the contact angle with the sessile drop protocol. The influence of roughness, test liquid and pre-crystallization of the samples as well as the storage temperature were investigated. In case of no pre-crystallization, a change in surface properties due to storage at 20 °C was detected, whereas samples stored at 30 °C showed the same wetting behaviour as fresh samples. This is associated with polymorphic transformation from thermodynamically less stable crystals to more stable configurations.

  18. Changes in contact angle providing evidence for surface alteration in multi-component solid foods

    International Nuclear Information System (INIS)

    Reinke, Svenja K; Hauf, Katharina; Heinrich, Stefan; Vieira, Josélio; Palzer, Stefan

    2015-01-01

    Chocolate blooming, one of the major problems in the confectionery industry, is the formation of visible white spots or a greyish haze on the surface of chocolate products due to large sugar or fat crystals on the surface. This leads to aesthetic changes and deterioration of taste and thus large sales losses for the confectionery industry due to consumer complaints. Chocolate blooming is often related to migration of lipids or sugar molecules to the chocolate surface, where they recrystallize with an associated polymorphic change of crystal structure on the surface. The wetting behaviour from contact angle measurements gives further insight into surface properties and is needed to determine surface energies and to evaluate possible migration mechanisms and preferred pathways. Therefore, an equilibrium contact angle is needed which is not directly accessible and is influenced by surface texture and interaction between solid and test liquid. In this study, the surface of cocoa butter and conventional chocolates was characterized by measuring the contact angle with the sessile drop protocol. The influence of roughness, test liquid and pre-crystallization of the samples as well as the storage temperature were investigated. In case of no pre-crystallization, a change in surface properties due to storage at 20 °C was detected, whereas samples stored at 30 °C showed the same wetting behaviour as fresh samples. This is associated with polymorphic transformation from thermodynamically less stable crystals to more stable configurations. (paper)

  19. Modeling and Analysis of The Pressure Die Casting Using Response Surface Methodology

    International Nuclear Information System (INIS)

    Kittur, Jayant K.; Herwadkar, T. V.; Parappagoudar, M. B.

    2010-01-01

    Pressure die casting is successfully used in the manufacture of Aluminum alloys components for automobile and many other industries. Die casting is a process involving many process parameters having complex relationship with the quality of the cast product. Though various process parameters have influence on the quality of die cast component, major influence is seen by the die casting machine parameters and their proper settings. In the present work, non-linear regression models have been developed for making predictions and analyzing the effect of die casting machine parameters on the performance characteristics of die casting process. Design of Experiments (DOE) with Response Surface Methodology (RSM) has been used to analyze the effect of effect of input parameters and their interaction on the response and further used to develop nonlinear input-output relationships. Die casting machine parameters, namely, fast shot velocity, slow shot to fast shot change over point, intensification pressure and holding time have been considered as the input variables. The quality characteristics of the cast product were determined by porosity, hardness and surface rough roughness (output/responses). Design of experiments has been used to plan the experiments and analyze the impact of variables on the quality of casting. On the other-hand Response Surface Methodology (Central Composite Design) is utilized to develop non-linear input-output relationships (regression models). The developed regression models have been tested for their statistical adequacy through ANOVA test. The practical usefulness of these models has been tested with some test cases. These models can be used to make the predictions about different quality characteristics, for the known set of die casting machine parameters, without conducting the experiments.

  20. Identifying the components in eggshell membrane responsible for reducing the heat resistance of bacterial pathogens.

    Science.gov (United States)

    Ahlborn, Gene; Sheldon, Brian W

    2006-04-01

    The biological activity (D-value determination) of eggshell membrane (ESM) was examined to determine the membrane components and mechanisms responsible for antibacterial activity. Biological and enzymatic activities (i.e., beta-N-acetylglucosaminidase [beta-NAGase], lysozyme, and ovotransferrin) of ESM denatured with trypsin, lipases, or heat were compared with those of untreated ESM. Trypsin-treated ESM lost all biological activity (D-values at 54 degrees C were 5.12 and 5.38 min for immobilized and solubilized trypsin, respectively) but showed no significant loss of enzymatic activities. Treatments with porcine lipase and a lipase cocktail did not impact biological or enzymatic activities. Heat denaturation of ESM (at 80 and 100 degrees C for 15 min) resulted in significant decreases in biological activity (D-values of 3.99 and 4.43 min, respectively) and loss of beta-NAGase activity. Lysozyme and ovotransferrin activities remained but were significantly reduced. Purified ESM and hen egg white components (i.e., beta-NAGase, lysozyme, and ovotransferrin) were added to Salmonella Typhimurium suspensions (in 0.1% peptone water) at varying concentrations to evaluate their biological activity. D-values at 54 degrees C were 4.50 and 3.68 min for treatment with lysozyme or beta-NAGase alone, respectively, and 2.44 min for ovotransferrin but 1.47 min for a combination of all three components (similar to values for ESM). Exposure of Salmonella Typhimurium cells to a mixture of ovotransferrin, lysozyme, and beta-NAGase or ESM resulted in significant increases in extracellular concentrations of Ca2+, Mg2+, and K+. Transmission electron microscopic examination of Salmonella Typhimurium cells treated with a combination of ovotransferrin, lysozyme, and beta-NAGase revealed membrane disruption and cell lysis. The findings of this study demonstrate that ovotransferrin, lysozyme, and beta-NAGase are the primary components responsible for ESM antibacterial activity. The

  1. Visual responses in mice lacking critical components of all known retinal phototransduction cascades.

    Directory of Open Access Journals (Sweden)

    Annette E Allen

    2010-11-01

    Full Text Available The mammalian visual system relies upon light detection by outer-retinal rod/cone photoreceptors and melanopsin-expressing retinal ganglion cells. Gnat1(-/-;Cnga3(-/-;Opn4(-/- mice lack critical elements of each of these photoreceptive mechanisms via targeted disruption of genes encoding rod α transducin (Gnat1; the cone-specific α3 cyclic nucleotide gated channel subunit (Cnga3; and melanopsin (Opn4. Although assumed blind, we show here that these mice retain sufficiently widespread retinal photoreception to drive a reproducible flash electroretinogram (ERG. The threshold sensitivity of this ERG is similar to that of cone-based responses, however it is lost under light adapted conditions. Its spectral efficiency is consistent with that of rod opsin, but not cone opsins or melanopsin, indicating that it originates with light absorption by the rod pigment. The TKO light response survives intravitreal injection of U73122 (a phospholipase C antagonist, but is inhibited by a missense mutation of cone α transducin (Gnat2(cpfl3, suggesting Gnat2-dependence. Visual responses in TKO mice extend beyond the retina to encompass the lateral margins of the lateral geniculate nucleus and components of the visual cortex. Our data thus suggest that a Gnat1-independent phototransduction mechanism downstream of rod opsin can support relatively widespread responses in the mammalian visual system. This anomalous rod opsin-based vision should be considered in experiments relying upon Gnat1 knockout to silence rod phototransduction.

  2. Kiwifruit Non-Sugar Components Reduce Glycaemic Response to Co-Ingested Cereal in Humans.

    Science.gov (United States)

    Mishra, Suman; Edwards, Haley; Hedderley, Duncan; Podd, John; Monro, John

    2017-10-30

    Kiwifruit (KF) effects on the human glycaemic response to co-ingested wheat cereal were determined. Participants (n = 20) consumed four meals in random order, all being made to 40 g of the same available carbohydrate, by adding kiwifruit sugars (KF sug; glucose, fructose, sucrose 2:2:1) to meals not containing KF. The meals were flaked wheat biscuit (WB)+KFsug, WB+KF, WB+guar gum+KFsug, WB+guar gum+KF, that was ingested after fasting overnight. Blood glucose was monitored 3 h and hunger measured at 180 min post-meal using a visual analogue scale. KF and guar reduced postprandial blood glucose response amplitude, and prevented subsequent hypoglycaemia that occurred with WB+KFsug. The area between the blood glucose response curve and baseline from 0 to 180 min was not significantly different between meals, 0-120 min areas were significantly reduced by KF and/or guar. Area from 120 to 180 min was positive for KF, guar, and KF+guar, while the area for the WB meal was negative. Hunger at 180 min was significantly reduced by KF and/or guar when compared with WB. We conclude that KF components other than available carbohydrate may improve the glycaemic response profile to co-ingested cereal food.

  3. Kiwifruit Non-Sugar Components Reduce Glycaemic Response to Co-Ingested Cereal in Humans

    Directory of Open Access Journals (Sweden)

    Suman Mishra

    2017-10-01

    Full Text Available Kiwifruit (KF effects on the human glycaemic response to co-ingested wheat cereal were determined. Participants (n = 20 consumed four meals in random order, all being made to 40 g of the same available carbohydrate, by adding kiwifruit sugars (KF sug; glucose, fructose, sucrose 2:2:1 to meals not containing KF. The meals were flaked wheat biscuit (WB+KFsug, WB+KF, WB+guar gum+KFsug, WB+guar gum+KF, that was ingested after fasting overnight. Blood glucose was monitored 3 h and hunger measured at 180 min post-meal using a visual analogue scale. KF and guar reduced postprandial blood glucose response amplitude, and prevented subsequent hypoglycaemia that occurred with WB+KFsug. The area between the blood glucose response curve and baseline from 0 to 180 min was not significantly different between meals, 0–120 min areas were significantly reduced by KF and/or guar. Area from 120 to 180 min was positive for KF, guar, and KF+guar, while the area for the WB meal was negative. Hunger at 180 min was significantly reduced by KF and/or guar when compared with WB. We conclude that KF components other than available carbohydrate may improve the glycaemic response profile to co-ingested cereal food.

  4. Adding a Performance-Based Component to Surface Warfare Officer Bonuses: Will it Affect Retention?

    National Research Council Canada - National Science Library

    Carman, Aron S; Mudd, Ryan M

    2008-01-01

    ... Authorization and the current officer inventory beginning at 9 years of commissioned service. The objective of this study was to analyze the 13-year retention effect of adding a performance-based component to the SWO Critical Skills Bonus (CSB...

  5. An Instrument for Inspecting Aspheric Optical Surfaces and Components, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This is a Phase II SBIR proposal to develop an extremely versatile optical inspection tool for aspheric optical components and optics that are not easily inspected...

  6. An Instrument for Inspecting Aspheric Optical Surfaces and Components, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This is a Phase I proposal to develop an extremely versatile optical inspection tool for determining the optical figure of aspheric optical components, such as test...

  7. Phosphoinositide-signaling is one component of a robust plant defense response.

    Directory of Open Access Journals (Sweden)

    Imara Yasmin Perera

    2014-06-01

    Full Text Available The phosphoinositide pathway and inositol-1,4,5-triphosphate (InsP3 have been implicated in plant responses to many abiotic stresses; however, their role in response to biotic stress is not well characterized. In the current study, we show that both basal defense and systemic acquired resistance responses are affected in transgenic plants constitutively expressing the human type I inositol polyphosphate 5-phosphatase (InsP 5-ptase which have greatly reduced InsP3 levels. Flagellin induced Ca2+-release as well as the expressions of some flg22 responsive genes were attenuated in the InsP 5-ptase plants. Furthermore, the InsP 5-ptase plants were more susceptible to virulent and avirulent strains of Pseudomonas syringae pv. tomato (PstDC3000. The InsP 5-ptase plants had lower basal salicylic acid (SA levels and the induction of SAR in systemic leaves was reduced and delayed. Reciprocal exudate experiments showed that although the InsP 5-ptase plants produced equally effective molecules that could trigger PR-1 gene expression in wild type plants, exudates collected from either wild type or InsP 5-ptase plants triggered less PR-1 gene expression in InsP 5-ptase plants. Additionally, expression profiles indicated that several defense genes including PR-1, PR-2, PR-5 and AIG1 were basally down regulated in the InsP 5-ptase plants compared with wild type. Upon pathogen attack, expression of these genes was either not induced or showed delayed induction in systemic leaves. Our study shows that phosphoinositide signaling is one component of the plant defense network and is involved in both basal and systemic responses. The dampening of InsP3-mediated signaling affects Ca2+ release, modulates defense gene expression and compromises plant defense responses.

  8. Postural threat differentially affects the feedforward and feedback components of the vestibular-evoked balance response.

    Science.gov (United States)

    Osler, Callum J; Tersteeg, M C A; Reynolds, Raymond F; Loram, Ian D

    2013-10-01

    Circumstances may render the consequence of falling quite severe, thus maximising the motivation to control postural sway. This commonly occurs when exposed to height and may result from the interaction of many factors, including fear, arousal, sensory information and perception. Here, we examined human vestibular-evoked balance responses during exposure to a highly threatening postural context. Nine subjects stood with eyes closed on a narrow walkway elevated 3.85 m above ground level. This evoked an altered psycho-physiological state, demonstrated by a twofold increase in skin conductance. Balance responses were then evoked by galvanic vestibular stimulation. The sway response, which comprised a whole-body lean in the direction of the edge of the walkway, was significantly and substantially attenuated after ~800 ms. This demonstrates that a strong reason to modify the balance control strategy was created and subjects were highly motivated to minimise sway. Despite this, the initial response remained unchanged. This suggests little effect on the feedforward settings of the nervous system responsible for coupling pure vestibular input to functional motor output. The much stronger, later effect can be attributed to an integration of balance-relevant sensory feedback once the body was in motion. These results demonstrate that the feedforward and feedback components of a vestibular-evoked balance response are differently affected by postural threat. Although a fear of falling has previously been linked with instability and even falling itself, our findings suggest that this relationship is not attributable to changes in the feedforward vestibular control of balance. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  9. Computational optimization of biodiesel combustion using response surface methodology

    Directory of Open Access Journals (Sweden)

    Ganji Prabhakara Rao

    2017-01-01

    Full Text Available The present work focuses on optimization of biodiesel combustion phenomena through parametric approach using response surface methodology. Physical properties of biodiesel play a vital role for accurate simulations of the fuel spray, atomization, combustion, and emission formation processes. Typically methyl based biodiesel consists of five main types of esters: methyl palmitate, methyl oleate, methyl stearate, methyl linoleate, and methyl linolenate in its composition. Based on the amount of methyl esters present the properties of pongamia bio-diesel and its blends were estimated. CONVERGETM computational fluid dynamics software was used to simulate the fuel spray, turbulence and combustion phenomena. The simulation responses such as indicated specific fuel consumption, NOx, and soot were analyzed using design of experiments. Regression equations were developed for each of these responses. The optimum parameters were found out to be compression ratio – 16.75, start of injection – 21.9° before top dead center, and exhaust gas re-circulation – 10.94%. Results have been compared with baseline case.

  10. The surface tension of pure liquids. Thermodynamic components and corresponding states

    NARCIS (Netherlands)

    Lyklema, J.

    1999-01-01

    From the temperature dependency of surface and interfacial tensions the surface excess energy and entropy per unit area can be obtained. The excess energy is a liquid-specific property; it varies over about three decades between liquid helium and molten metals. On the other hand, the excess entropy

  11. Influence of the hydrostatic stress component on critical surface expansion in forging compound products

    DEFF Research Database (Denmark)

    Vorm, T; Bay, Niels; Wanheim, Tarras

    1974-01-01

    of a superimposed hydrostatic pressure on the critical surface expansion during a forging process. The critical surface expansion appears to decrease with increasing hydrostatic pressure. This may be due to the fact that the close contact between the materials necessary to obtain bonding is created by a micro...

  12. Identification and characterization of sigma, a novel component of the Staphylococcus aureus stress and virulence responses.

    Directory of Open Access Journals (Sweden)

    Lindsey N Shaw

    Full Text Available S. aureus is a highly successful pathogen that is speculated to be the most common cause of human disease. The progression of disease in S. aureus is subject to multi-factorial regulation, in response to the environments encountered during growth. This adaptive nature is thought to be central to pathogenesis, and is the result of multiple regulatory mechanisms employed in gene regulation. In this work we describe the existence of a novel S. aureus regulator, an as yet uncharacterized ECF-sigma factor (sigma(S, that appears to be an important component of the stress and pathogenic responses of this organism. Using biochemical approaches we have shown that sigma(S is able to associates with core-RNAP, and initiate transcription from its own coding region. Using a mutant strain we determined that sigma(S is important for S. aureus survival during starvation, extended exposure to elevated growth temperatures, and Triton X-100 induced lysis. Coculture studies reveal that a sigma(S mutant is significantly outcompeted by its parental strain, which is only exacerbated during prolonged growth (7 days, or in the presence of stressor compounds. Interestingly, transcriptional analysis determined that under standard conditions, S. aureus SH1000 does not initiate expression of sigS. Assays performed hourly for 72 h revealed expression in typically background ranges. Analysis of a potential anti-sigma factor, encoded downstream of sigS, revealed it to have no obvious role in the upregulation of sigS expression. Using a murine model of septic arthritis, sigS-mutant infected animals lost significantly less weight, developed septic arthritis at significantly lower levels, and had increased survival rates. Studies of mounted immune responses reveal that sigS-mutant infected animals had significantly lower levels of IL-6, indicating only a weak immunological response. Finally, strains of S. aureus lacking sigS were far less able to undergo systemic dissemination

  13. Cost effective production of pullulan from agri-industrial residues using response surface methodology.

    Science.gov (United States)

    Mehta, Ananya; Prasad, G S; Choudhury, Anirban Roy

    2014-03-01

    Response surface methodology was used to develop an economically feasible process for the fermentative production of pullulan using agri-industrial residues, jaggery, de-oiled jatropha seed cake (DOJSC) and corn steep liquor (CSL), as sole media components. A second order polynomial model was obtained using central composite design to understand the effects of interactions among these substrates on pullulan biosynthesis. Results indicated that, lower concentrations of CSL and DOJSC and higher concentrations of jaggery favoured pullulan production. The optimal nutrient composition (18% jaggery, 3% DOJSC and 0.97% CSL) as suggested by the model resulted in production of 66.25 g/L pullulan with a productivity of 0.92 g/Lh. Analysis of raw material cost component for pullulan production suggested that sole utilization of agri-residues may lead to development of cost effective process for pullulan production. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Dissecting Low Atmospheric Pressure Stress: Transcriptome Responses to the Components of Hypobaria in Arabidopsis.

    Science.gov (United States)

    Zhou, Mingqi; Callaham, Jordan B; Reyes, Matthew; Stasiak, Michael; Riva, Alberto; Zupanska, Agata K; Dixon, Mike A; Paul, Anna-Lisa; Ferl, Robert J

    2017-01-01

    Controlled hypobaria presents biology with an environment that is never encountered in terrestrial ecology, yet the apparent components of hypobaria are stresses typical of terrestrial ecosystems. High altitude, for example, presents terrestrial hypobaria always with hypoxia as a component stress, since the relative partial pressure of O 2 is constant in the atmosphere. Laboratory-controlled hypobaria, however, allows the dissection of pressure effects away from the effects typically associated with altitude, in particular hypoxia, as the partial pressure of O 2 can be varied. In this study, whole transcriptomes of plants grown in ambient (97 kPa/pO 2 = 21 kPa) atmospheric conditions were compared to those of plants transferred to five different atmospheres of varying pressure and oxygen composition for 24 h: 50 kPa/pO 2 = 10 kPa, 25 kPa/pO 2 = 5 kPa, 50 kPa/pO 2 = 21 kPa, 25 kPa/pO 2 = 21 kPa, or 97 kPa/pO 2 = 5 kPa. The plants exposed to these environments were 10 day old Arabidopsis seedlings grown vertically on hydrated nutrient plates. In addition, 5 day old plants were also exposed for 24 h to the 50 kPa and ambient environments to evaluate age-dependent responses. The gene expression profiles from roots and shoots showed that the hypobaric response contained more complex gene regulation than simple hypoxia, and that adding back oxygen to normoxic conditions did not completely alleviate gene expression changes in hypobaric responses.

  15. Dissecting Low Atmospheric Pressure Stress: Transcriptome Responses to the Components of Hypobaria in Arabidopsis

    Science.gov (United States)

    Zhou, Mingqi; Callaham, Jordan B.; Reyes, Matthew; Stasiak, Michael; Riva, Alberto; Zupanska, Agata K.; Dixon, Mike A.; Paul, Anna-Lisa; Ferl, Robert J.

    2017-01-01

    Controlled hypobaria presents biology with an environment that is never encountered in terrestrial ecology, yet the apparent components of hypobaria are stresses typical of terrestrial ecosystems. High altitude, for example, presents terrestrial hypobaria always with hypoxia as a component stress, since the relative partial pressure of O2 is constant in the atmosphere. Laboratory-controlled hypobaria, however, allows the dissection of pressure effects away from the effects typically associated with altitude, in particular hypoxia, as the partial pressure of O2 can be varied. In this study, whole transcriptomes of plants grown in ambient (97 kPa/pO2 = 21 kPa) atmospheric conditions were compared to those of plants transferred to five different atmospheres of varying pressure and oxygen composition for 24 h: 50 kPa/pO2 = 10 kPa, 25 kPa/pO2 = 5 kPa, 50 kPa/pO2 = 21 kPa, 25 kPa/pO2 = 21 kPa, or 97 kPa/pO2 = 5 kPa. The plants exposed to these environments were 10 day old Arabidopsis seedlings grown vertically on hydrated nutrient plates. In addition, 5 day old plants were also exposed for 24 h to the 50 kPa and ambient environments to evaluate age-dependent responses. The gene expression profiles from roots and shoots showed that the hypobaric response contained more complex gene regulation than simple hypoxia, and that adding back oxygen to normoxic conditions did not completely alleviate gene expression changes in hypobaric responses. PMID:28443120

  16. Laser structuring and modification of surfaces for chemical and medical micro components

    Science.gov (United States)

    Bremus-Koebberling, Elke A.; Gillner, Arnold

    2003-11-01

    In the production of micro devices for applications in chemistry, biotechnology and medical technologies surface properties become more and more important. The microscale topography and surface chemistry have influence on wetting properties and cell behavior. Therefore the design of material surface determines the success of artificial devices in contact with biological systems. For applications in the field of medical implants laser technologies have been developed for micro structuring of polymers to modify the surface properties with respect to wettability and controlled cell growth. The technology is based on excimer laser treatment of polymer surfaces using laser wavelength 193 nm (ArF) with different fluences and cumulated energies. Depending on the processing parameters and examined polymers either hydrophobic or hydrophilic surfaces can be increased. The water contact angle of polydimethylsiloxane (PDMS) for example can be increased from 113° to approx. 150° so that the surface exhibits the so called lotus effect. The laser generated micro patterns reveal influence on cell density and cell distribution which can be used for cell guidance. Results for cell growing experiments are shown for different polymers.

  17. Ionospheric convection response to changes of interplanetary magnetic field B-z component during strong B-y component

    DEFF Research Database (Denmark)

    Huang, C.S.; Murr, D.; Sofko, G.J.

    2000-01-01

    the dawn-dusk meridian plane, which is interpreted as propagation or expansion of newly generated convection cells in the cusp region. Other studies showed that the change in convection pattern in response to IMF reorientations is spatially fixed. In this paper, we investigate the ionospheric convection...... response to IMF Bz changes during strong IMF BZ. On March 23, 1995, B-x was small, B-y was strongly positive (7-11 nT), and the B-z polarity changed several times after 1300 UT. The dayside ionospheric convection is dominated by a large clockwise convection cell. The cell focus (the "eye" of the convection...... pattern) is located in the prenoon sector for northward B-z and in the postnoon sector for southward B-z. It is found that the cell focus shifts from the prenoon sector to the postnoon sector following a southward BL turning and vice versa for a northward B-z turning. However, the motion of the convection...

  18. Advancement of the arc-waterjet cutting to a gouging process for contaminated surface activity of steel components

    International Nuclear Information System (INIS)

    Bach, F.W.; Bruening, D.

    1990-01-01

    The technique of arc-waterjet cutting had to be progressed so that it is possible to gouge the surface of metallic components of nuclear power plants. With applicable cutting parameters depending on the thickness of the contamination the surface had to be gouged and converted to a granulation that is to remove. A continously pulled out wire electrode strikes an arc to the workpeace by short circuit and melts both. A concentric around the wire placed waterjet is able to wash the liquid metal away. With a computer numeric control it is possible to remove the surface of metal up to a deep penetration of 4 to 5 mm. With arc waterjet gouging a remote-controlled removal of contaminated surface activity in shutdowned nuclear power plants under water is possible. (orig./HP) With 15 refs., 1 tab., 14 figs [de

  19. OPTIMIZATION OF TANNASE POSITIVE PROBIOTIC PRODUCTION BY SURFACE RESPONSE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Yumnam S.

    2014-10-01

    Full Text Available Study in conditions in vitro of eight Lactobacillus strains procured from culture repositories for their probiotic potential and extracellular tannase activity was the aim of the research. Based upon acid, bile salt tolerance and antibiotic resistance L. plantarum MTCC 2621 with high tannase activity was selected for production studies. Optimization of nutrient medium in 3 L bioreactor was optimized by Surface Response Methodology based on the Full Factorial Central Composite Design. A factorial design 23 augmented by 6 axial points (α = 1.68 and six replicates at the center point was implemented in 20 experiments. The optimized conditions were found to be pH 5.69, contain of lactose 128.58 g/l, peptone 8 g/l. A tenfold increase in the biomass production was observed using the optimized nutrient medium in bioreactor as compared to initial MRS medium.

  20. Application of response surface methodology method in designing corrosion inhibitor

    Science.gov (United States)

    Asmara, Y. P.; Athirah; Siregar, J. P.; Kurniawan, T.; Bachtiar, D.

    2017-10-01

    In oil and gas pipelines and offshore structure, inhibitors have been considered to be the first choice to reduce corrosion rate. There are many corrosion inhibitor compositions available in the market. To produce the best corrosion inhibitor requires many experimental data which is not efficient. These experiments used response surface methodology (RSM) to select corrosion inhibitor compositions. The experiments investigated effects of corrosion inhibition on corrosion rate of low carbon steel in 3% NaCl solution with different concentrations of selected main inhibitor compositions which are ethyl acetate (EA), ethylene glycol (EG) and sodium benzoate (SB). Corrosion rate were calculated using linear polarization resistance (LPR). All of the experiments were set in natural conditions at pH 7. MINITAB® version 15 was used for data analysis. It is shown that a quadratic model is a representative model can predict best corrosion inhibitor composition comprehensibly.

  1. Maximization of fructose esters synthesis by response surface methodology.

    Science.gov (United States)

    Neta, Nair Sampaio; Peres, António M; Teixeira, José A; Rodrigues, Ligia R

    2011-07-01

    Enzymatic synthesis of fructose fatty acid ester was performed in organic solvent media, using a purified lipase from Candida antartica B immobilized in acrylic resin. Response surface methodology with a central composite rotatable design based on five levels was implemented to optimize three experimental operating conditions (temperature, agitation and reaction time). A statistical significant cubic model was established. Temperature and reaction time were found to be the most significant parameters. The optimum operational conditions for maximizing the synthesis of fructose esters were 57.1°C, 100 rpm and 37.8 h. The model was validated in the identified optimal conditions to check its adequacy and accuracy, and an experimental esterification percentage of 88.4% (±0.3%) was obtained. These results showed that an improvement of the enzymatic synthesis of fructose esters was obtained under the optimized conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Aerodynamic configuration design using response surface methodology analysis

    Science.gov (United States)

    Engelund, Walter C.; Stanley, Douglas O.; Lepsch, Roger A.; Mcmillin, Mark M.; Unal, Resit

    1993-01-01

    An investigation has been conducted to determine a set of optimal design parameters for a single-stage-to-orbit reentry vehicle. Several configuration geometry parameters which had a large impact on the entry vehicle flying characteristics were selected as design variables: the fuselage fineness ratio, the nose to body length ratio, the nose camber value, the wing planform area scale factor, and the wing location. The optimal geometry parameter values were chosen using a response surface methodology (RSM) technique which allowed for a minimum dry weight configuration design that met a set of aerodynamic performance constraints on the landing speed, and on the subsonic, supersonic, and hypersonic trim and stability levels. The RSM technique utilized, specifically the central composite design method, is presented, along with the general vehicle conceptual design process. Results are presented for an optimized configuration along with several design trade cases.

  3. Enhancing nitrilase production from Fusarium proliferatum using response surface methodology.

    Science.gov (United States)

    Yusuf, Farnaz; Chaubey, Asha; Raina, Arvind; Jamwal, Urmila; Parshad, Rajinder

    2013-12-01

    The individual and interactive effects of three independent variables i.e. carbon source (glucose), nitrogen source (sodium nitrate) and inducer (ϵ-caprolactam) on nitrilase production from Fusarium proliferatum were investigated using design of experiments (DOE) methodology. Response surface methodology (RSM) was followed to generate the process model and to obtain the optimal conditions for maximum nitrilase production. Based on central composite design (CCD) a quadratic model was found to fit the experimental data (pnitrilase activity of 58.3U/g biomass obtained experimentally correlated to the predicted activity which proves the authenticity of the model. Overall 2.24 fold increase in nitrilase activity was achieved as compared to the activity before optimization (26U/g biomass).

  4. Double Lap Shear Testing of Coating-Modified Ice Adhesion to Specific Shuttle Component Surfaces

    National Research Council Canada - National Science Library

    Ferrick, M. G; Mulherin, Nathan D; Coutermarsh, Barry A; Durell, Glenn D; Curtis, Leslie A; St. Clair, Terry L; Weiser, Erik S; Cano, Roberto J; Smith, Trent M; Stevenson, Charles G; Martinez, Eloy C

    2006-01-01

    The goals of this experimental program were to optimize the effectiveness of an icephobic coating for use on several Space Shuttle surfaces, to evaluate the effects of adding an ultraviolet light absorber (UVA...

  5. Optimism and pessimism are related to different components of the stress response in healthy older people.

    Science.gov (United States)

    Puig-Perez, Sara; Villada, Carolina; Pulopulos, Matias M; Almela, Mercedes; Hidalgo, Vanesa; Salvador, Alicia

    2015-11-01

    Some personality traits have key importance for health because they can affect the maintenance and evolution of different disorders with a high prevalence in older people, including stress pathologies and diseases. In this study we investigated how two relevant personality traits, optimism and pessimism, affect the psychophysiological response of 72 healthy participants (55 to 76 years old) exposed to either a psychosocial stress task (Trier Social Stress Test, TSST) or a control task; salivary cortisol, heart rate (HR) and situational appraisal were measured. Our results showed that optimism was related to faster cortisol recovery after exposure to stress. Pessimism was not related to the physiological stress response, but it was associated with the perception of the stress task as more difficult. Thus, higher optimism was associated with better physiological adjustment to a stressful situation, while higher pessimism was associated with worse psychological adjustment to stress. These results highlight different patterns of relationships, with optimism playing a more important role in the physiological component of the stress response, and pessimism having a greater effect on situational appraisal. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Light and circadian regulation of clock components aids flexible responses to environmental signals

    Science.gov (United States)

    Dixon, Laura E; Hodge, Sarah K; van Ooijen, Gerben; Troein, Carl; Akman, Ozgur E; Millar, Andrew J

    2014-01-01

    The circadian clock measures time across a 24 h period, increasing fitness by phasing biological processes to the most appropriate time of day. The interlocking feedback loop mechanism of the clock is conserved across species; however, the number of loops varies. Mathematical and computational analyses have suggested that loop complexity affects the overall flexibility of the oscillator, including its responses to entrainment signals. We used a discriminating experimental assay, at the transition between different photoperiods, in order to test this proposal in a minimal circadian network (in Ostreococcus tauri) and a more complex network (in Arabidopsis thaliana). Transcriptional and translational reporters in O. tauri primarily tracked dawn or dusk, whereas in A. thaliana, a wider range of responses were observed, consistent with its more flexible clock. Model analysis supported the requirement for this diversity of responses among the components of the more complex network. However, these and earlier data showed that the O. tauri network retains surprising flexibility, despite its simple circuit. We found that models constructed from experimental data can show flexibility either from multiple loops and/or from multiple light inputs. Our results suggest that O. tauri has adopted the latter strategy, possibly as a consequence of genomic reduction. PMID:24842166

  7. Genetic Components of Root Architecture Remodeling in Response to Salt Stress

    KAUST Repository

    Julkowska, Magdalena

    2017-11-07

    Salinity of the soil is highly detrimental to plant growth. Plants respond by a redistribution of root mass between main and lateral roots, yet the genetic machinery underlying this process is still largely unknown. Here, we describe the natural variation among 347 Arabidopsis thaliana accessions in root system architecture (RSA) and identify the traits with highest natural variation in their response to salt. Salt-induced changes in RSA were associated with 100 genetic loci using genome-wide association studies (GWAS). Two candidate loci associated with lateral root development were validated and further investigated. Changes in CYP79B2 expression in salt stress positively correlated with lateral root development in accessions, and cyp79b2 cyp79b3 double mutants developed fewer and shorter lateral roots under salt stress, but not in control conditions. By contrast, high HKT1 expression in the root repressed lateral root development, which could be partially rescued by addition of potassium. The collected data and Multi-Variate analysis of multiple RSA traits, available through the Salt_NV_Root App, capture root responses to salinity. Together, our results provide a better understanding of effective RSA remodeling responses, and the genetic components involved, for plant performance in stress conditions.

  8. Effect of metal surface composition on deposition behavior of stainless steel component dissolved in liquid sodium

    International Nuclear Information System (INIS)

    Yokota, Norikatsu; Shimoyashiki, Shigehiro

    1988-01-01

    Deposition behavior of corrosion products has been investigated to clarify the effect of metal surface composition on the deposition process in liquid sodium. For the study a sodium loop made of Type 304 stainless steel was employed. Deposition test pieces, which were Type 304 stainless steel, iron, nickel or Inconel 718, were immersed in the sodium pool of the test pot. Corrosion test pieces, which were Type 304 stainless steel, 50 at% Fe-50 at%Mn and Inconel 718, were set in a heater pin assembly along the axial direction of the heater pin surface. Sodium temperatures at the outlet and inlet of the heater pin assembly were controlled at 943 and 833 K, respectively. Sodium was purified at a cold trap temperature of 393 K and the deposition test was carried out for 4.3 x 10 2 - 2.9 x 10 4 ks. Several crystallized particles were observed on the surface of the deposition test pieces. The particles had compositions and crystal structures which depended on both the composition of deposition test pieces and the concentration of iron and manganese in sodium. Only iron-rich particles having a polyhedral shape deposited on the iron surface. Two types of particles, iron-rich α-phase and γ-phase with nearly the same composition as stainless steel, were deposited on Type 304 stainless steel. A Ni-Mn alloy was deposited on the nickel surface in the case of a higher concentration of manganese in sodium. On the other hand, for a lower manganese concentration, a Fe-Ni alloy was precipitated on the nickel surface. Particles deposited on nickel had a γ-phase crystal structure similar to the deposition test piece of nickel. Hence, the deposition process can be explained as follows: Corrosion products in liquid sodium were deposited on the metal surface by forming a metal alloy selectively with elements of the metal surface. (author)

  9. Surface texturing of Si3N4–SiC ceramic tool components by pulsed laser machining

    CSIR Research Space (South Africa)

    Tshabalala, LC

    2016-03-01

    Full Text Available Article Type: Full Length Article Keywords: silicon nitride; pulsed laser machining; surface texturing; material removal; roughness Corresponding Author: Mrs. Lerato Criscelda Tshabalala, MTech Corresponding Author's Institution: Tshwane... show the material response to various laser parameters (pulse energy and pulse overlap). For this article, we only focused on profiling the material removal depth, scan width, material removal rates and the surface roughness after using two...

  10. Quantitative studies of rhubarb using quantitative analysis of multicomponents by single marker and response surface methodology.

    Science.gov (United States)

    Sun, Jiachen; Wu, Yueting; Dong, Shengjie; Li, Xia; Gao, Wenyuan

    2017-10-01

    In this work, we developed a novel approach to evaluate the contents of bioactive components in rhubarb. The present method was based on the quantitative analysis of multicomponents by a single-marker and response surface methodology approaches. The quantitative analysis of multicomponents by a single-marker method based on high-performance liquid chromatography coupled with photodiode array detection was developed and applied to determine the contents of 12 bioactive components in rhubarb. No significant differences were found in the results from the quantitative analysis of multicomponents by a single-marker and the external standard method. In order to maximize the extraction of 12 bioactive compounds in rhubarb, the ultrasonic-assisted extraction conditions were obtained by the response surface methodology coupled with Box-Behnken design. According to the obtained results, we showed that the optimal conditions would be as follows: proportion of ethanol/water 74.39%, solvent-to-solid ratio 24.07:1 v/w, extraction time 51.13 min, and extraction temperature 63.61°C. The analytical scheme established in this research should be a reliable, convenient, and appropriate method for quantitative determination of bioactive compounds in rhubarb. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Understanding the biological responses of nanostructured metals and surfaces

    Science.gov (United States)

    Lowe, Terry C.; Reiss, Rebecca A.

    2014-08-01

    Metals produced by Severe Plastic Deformation (SPD) offer distinct advantages for medical applications such as orthopedic devices, in part because of their nanostructured surfaces. We examine the current theoretical foundations and state of knowledge for nanostructured biomaterials surface optimization within the contexts that apply to bulk nanostructured metals, differentiating how their microstructures impact osteogenesis, in particular, for Ultrafine Grained (UFG) titanium. Then we identify key gaps in the research to date, pointing out areas which merit additional focus within the scientific community. For example, we highlight the potential of next-generation DNA sequencing techniques (NGS) to reveal gene and non-coding RNA (ncRNA) expression changes induced by nanostructured metals. While our understanding of bio-nano interactions is in its infancy, nanostructured metals are already being marketed or developed for medical devices such as dental implants, spinal devices, and coronary stents. Our ability to characterize and optimize the biological response of cells to SPD metals will have synergistic effects on advances in materials, biological, and medical science.

  12. Influences of surface and solvent on retention of HEMA/mixture components after evaporation.

    Science.gov (United States)

    Garcia, Fernanda C P; Wang, Linda; Pereira, Lúcia C G; de Andrade e Silva, Safira M; Júnior, Luiz M; Carrilho, Marcela Rocha de Oliveira

    2010-01-01

    This study examined the retention of solvents within experimental HEMA/solvent primers after two conditions for solvent evaporation: from a free surface or from dentine surface. Experimental primers were prepared by mixing 35% HEMA with 65% water, methanol, ethanol or acetone (v/v). Aliquots of each primer (50 microl) were placed on glass wells or they were applied to the surface of acid-etched dentine cubes (2mm x 2mm x 2mm) (n=5). For both conditions (i.e. from free surface or dentine cubes), change in primers mass due to solvent evaporation was gravimetrically measured for 10min at 51% RH and 21 degrees C. The rate of solvent evaporation was calculated as a function of loss of primers mass (%) over time. Data were analysed by two-way ANOVA and Student-Newman-Keuls (pevaporation rate (%/min) depending on the solvent present in the primer and the condition for evaporation (from free surface or dentine cubes) (pevaporation for HEMA/acetone primer was almost 2- to 10-times higher than for HEMA/water primer depending whether evaporation occurred, respectively, from a free surface or dentine cubes. The rate of solvent evaporation varied with time, being in general highest at the earliest periods. The rate of solvent evaporation and its retention into HEMA/solvent primers was influenced by the type of the solvent and condition allowed for their evaporation.

  13. Optimization of sustained release aceclofenac microspheres using response surface methodology

    International Nuclear Information System (INIS)

    Deshmukh, Rameshwar K.; Naik, Jitendra B.

    2015-01-01

    Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14 ± 0.015% to 85.34 ± 0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12 h. The optimized microspheres formulation showed E.E. of 84.87 ± 0.005 with small error value (1.39). The low magnitudes of error and the significant value of R 2 in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects. - Highlights: • Aceclofenac microspheres were

  14. Optimization of sustained release aceclofenac microspheres using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Deshmukh, Rameshwar K.; Naik, Jitendra B., E-mail: jitunaik@gmail.com

    2015-03-01

    Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14 ± 0.015% to 85.34 ± 0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12 h. The optimized microspheres formulation showed E.E. of 84.87 ± 0.005 with small error value (1.39). The low magnitudes of error and the significant value of R{sup 2} in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects. - Highlights: • Aceclofenac microspheres

  15. Principal component analysis of the CT density histogram to generate parametric response maps of COPD

    Science.gov (United States)

    Zha, N.; Capaldi, D. P. I.; Pike, D.; McCormack, D. G.; Cunningham, I. A.; Parraga, G.

    2015-03-01

    Pulmonary x-ray computed tomography (CT) may be used to characterize emphysema and airways disease in patients with chronic obstructive pulmonary disease (COPD). One analysis approach - parametric response mapping (PMR) utilizes registered inspiratory and expiratory CT image volumes and CT-density-histogram thresholds, but there is no consensus regarding the threshold values used, or their clinical meaning. Principal-component-analysis (PCA) of the CT density histogram can be exploited to quantify emphysema using data-driven CT-density-histogram thresholds. Thus, the objective of this proof-of-concept demonstration was to develop a PRM approach using PCA-derived thresholds in COPD patients and ex-smokers without airflow limitation. Methods: Fifteen COPD ex-smokers and 5 normal ex-smokers were evaluated. Thoracic CT images were also acquired at full inspiration and full expiration and these images were non-rigidly co-registered. PCA was performed for the CT density histograms, from which the components with the highest eigenvalues greater than one were summed. Since the values of the principal component curve correlate directly with the variability in the sample, the maximum and minimum points on the curve were used as threshold values for the PCA-adjusted PRM technique. Results: A significant correlation was determined between conventional and PCA-adjusted PRM with 3He MRI apparent diffusion coefficient (p<0.001), with CT RA950 (p<0.0001), as well as with 3He MRI ventilation defect percent, a measurement of both small airways disease (p=0.049 and p=0.06, respectively) and emphysema (p=0.02). Conclusions: PRM generated using PCA thresholds of the CT density histogram showed significant correlations with CT and 3He MRI measurements of emphysema, but not airways disease.

  16. Responsiveness of cold tolerant chickpea characteristics in fall and spring planting: II. yield and yield components

    Directory of Open Access Journals (Sweden)

    ahmad nezami

    2009-06-01

    Full Text Available Previous research in Mashhad collection chickpeas (MCC has shown that there are some cold tolerant genotypes for fall planting in the highlands. To obtain more detailed information about the reaction of these genotypes to fall and spring planting, the yield and yield component responses of 33 chickpea genotypes (32 cold tolerant genotypes and one susceptible genotypes to four planting dates (28 Sep., 16 Oct., 2 Nov., and 7 Mar. were evaluated in 2000-2001 growing season. The experiment was conducted at the experimental field of college of agriculture, Ferdowsi University of Mashhad as a split plot design with two replications. The planting dates were imposed as main plot and chickpea genotypes as subplot. Effects of planting date and genotype on percent of plant survival (PPS after winter, number. of pod per plant, 100 seed weight, yield and Harvest Index (HI were significant (p

  17. Writing-skills Intervention Programming and its being a Component of Response to Intervention

    Directory of Open Access Journals (Sweden)

    Michael William Dunn

    2014-11-01

    Full Text Available For a struggling writer, step-by-step instruction can be a helpful means to manage organizing and producing elaborate text. This mixed-methods project offered four struggling writers a mnemonic strategy called Ask, Reflect, Text (ART in 45-minute sessions over 22 days. The second- and fourth-grade students attended a public school in the US Pacific Northwest. As a parallel component to the project, the students’ teachers and intervention specialist met with the author for 4 one-hour sessions to discuss: 1 the children’s intervention programming and progress, and 2 the paradigm of response to intervention (RTI and their thoughts about its feasibility in classrooms. The end-of-project assessment data demonstrated that the children made progress with writing skills, but the teachers and intervention specialist felt that support personnel would be needed to manage RTI-type intervention programming in general education classrooms.

  18. Thermal-structural response of EBR-II major components under reactor operational transients

    International Nuclear Information System (INIS)

    Chang, L.K.; Lee, M.J.

    1983-01-01

    Until recently, the LMFBR safety research has been focused primarily on severe but highly unlikely accident, such as hypothetical-core-disruptive accidents (HCDA's), and not enough attention has been given to accident prevention, which is less severe but more likely sequence. The objective of the EBR-II operational reliability testing (ORT) is to demonstrate that the reactor can be designed and operated to prevent accident. A series of mild duty cycles and overpower transients were designed for accident prevention tests. An assessment of the EBR-II major plant components has been performed to assure structural integrity of the reactor plant for the ORT program. In this paper, the thermal-structural response and structural evaluation of the reactor vessel, the reactor-vessel cover, the intermediate heat exchanger (IHX) and the superheater are presented

  19. Design and Analysis of a Micromechanical Three-Component Force Sensor for Characterizing and Quantifying Surface Roughness

    Directory of Open Access Journals (Sweden)

    Liang Q.

    2015-10-01

    Full Text Available Roughness, which can represent the trade-off between manufacturing cost and performance of mechanical components, is a critical predictor of cracks, corrosion and fatigue damage. In order to measure polished or super-finished surfaces, a novel touch probe based on three-component force sensor for characterizing and quantifying surface roughness is proposed by using silicon micromachining technology. The sensor design is based on a cross-beam structure, which ensures that the system possesses high sensitivity and low coupling. The results show that the proposed sensor possesses high sensitivity, low coupling error, and temperature compensation function. The proposed system can be used to investigate micromechanical structures with nanometer accuracy.

  20. Synthetic Three-Component HIV-1 V3 Glycopeptide Immunogens Induce Glycan-Dependent Antibody Responses.

    Science.gov (United States)

    Cai, Hui; Orwenyo, Jared; Giddens, John P; Yang, Qiang; Zhang, Roushu; LaBranche, Celia C; Montefiori, David C; Wang, Lai-Xi

    2017-12-21

    Eliciting broadly neutralizing antibody (bNAb) responses against HIV-1 is a major goal for a prophylactic HIV-1 vaccine. One approach is to design immunogens based on known broadly neutralizing epitopes. Here we report the design and synthesis of an HIV-1 glycopeptide immunogen derived from the V3 domain. We performed glycopeptide epitope mapping to determine the minimal glycopeptide sequence as the epitope of V3-glycan-specific bNAbs PGT128 and 10-1074. We further constructed a self-adjuvant three-component immunogen that consists of a 33-mer V3 glycopeptide epitope, a universal T helper epitope P30, and a lipopeptide (Pam 3 CSK 4 ) that serves as a ligand of Toll-like receptor 2. Rabbit immunization revealed that the synthetic self-adjuvant glycopeptide could elicit substantial glycan-dependent antibodies that exhibited broader recognition of HIV-1 gp120s than the non-glycosylated V3 peptide. These results suggest that the self-adjuvant synthetic glycopeptides can serve as an important component to elicit glycan-specific antibodies in HIV vaccine design. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Clonidine improves attentional and memory components of delayed response performance in a model of early Parkinsonism.

    Science.gov (United States)

    Schneider, J S; Tinker, J P; Decamp, E

    2010-08-25

    Cognitive deficits, including attention and working memory deficits, are often described in Parkinson's disease (PD) patients even during the early stages of the disease. However, cognitive deficits associated with PD have proven difficult to treat and often do not respond well to the dopaminergic therapies used to treat the motor symptoms of the disease. Chronic administration of low doses of the neurotoxin 1-methy,4-phenyl,1,2,3,6-tetrahydropyridine (MPTP) can induce cognitive dysfunction in non-human primates, including impaired performance on a variable delayed response (VDR) task with attentional and memory components. Since alpha-2 adrenergic receptor agonists have been suggested to improve attention and working memory in a variety of conditions, the present study assessed the extent to which the alpha-2 noradrenergic agonist clonidine might influence VDR performance in early Parkinsonian non-human primates. Clonidine (0.02-0.10 mg/kg) improved performance on both attentional and memory components of the task, performed in a modified Wisconsin General Test Apparatus, in a dose-dependent manner and the cognition enhancing effects of clonidine were blocked by co-administration of the alpha-2 noradrenergic antagonist idazoxan (0.10 mg/kg). These data suggest that clonidine or drugs of this class, perhaps with greater receptor subtype selectivity and low sedation liability, might be effective therapeutics for cognitive dysfunction associated with PD. Copyright 2010 Elsevier B.V. All rights reserved.

  2. Reduction of surface hydrophobicity using a stimulus-responsive polysaccharide.

    Science.gov (United States)

    Sedeva, Iliana G; Fornasiero, Daniel; Ralston, John; Beattie, David A

    2010-10-19

    The adsorption of carboxymethyl cellulose (CMC) onto a hydrophobic self-assembled monolayer has been characterized using the quartz crystal microbalance (with dissipation monitoring, QCM-D). Adsorption was studied as a function of initial solution conditions. CMC adsorbs to a greater extent at high ionic strength (10(-1) M KCl as opposed to 10(-2) M KCl) or low pH (3 as opposed to 9). The solution conditions that yielded the lowest initial adsorbed amount (10(-2) M KCl, pH 9) were used as a reference to investigate the response of the adsorbed layer to a switch in solution conditions after adsorption (i.e., to higher ionic strength (10(-1) M KCl) or lower pH (pH 3)). The adsorbed layer released significant amounts of hydration water after each solution switch, as determined by the QCM-D measurements. This expulsion of hydration water was fully reversible. For the two solution switches, reducing the solution pH resulted in a more pronounced change in the amount of hydration water within the adsorbed CMC, accompanied by a distinct conformational change, as determined from a QCM D-f plot. In addition to studying adsorption using QCM-D, the effect of adsorbed CMC on surface hydrophobicity has been investigated using captive bubble contact angle measurements. The effect of the polymer on the contact angle of the surface was seen to be greatest when adsorbed at low pH or at higher ionic strength. CMC was also seen to have a significantly enhanced ability to reduce the surface hydrophobicity after both the ionic strength and pH switches, lowering the advancing water contact angle by 6 and 23° and the receding water contact angle by 10 and 40° for the ionic strength and pH switches, respectively. As with the change in hydration water content, the change in the contact angle of the polymer-coated surface following the solution switches was reversible.

  3. A probability index for surface zonda wind occurrence at Mendoza city through vertical sounding principal components analysis

    Science.gov (United States)

    Otero, Federico; Norte, Federico; Araneo, Diego

    2018-01-01

    The aim of this work is to obtain an index for predicting the probability of occurrence of zonda event at surface level from sounding data at Mendoza city, Argentine. To accomplish this goal, surface zonda wind events were previously found with an objective classification method (OCM) only considering the surface station values. Once obtained the dates and the onset time of each event, the prior closest sounding for each event was taken to realize a principal component analysis (PCA) that is used to identify the leading patterns of the vertical structure of the atmosphere previously to a zonda wind event. These components were used to construct the index model. For the PCA an entry matrix of temperature ( T) and dew point temperature (Td) anomalies for the standard levels between 850 and 300 hPa was build. The analysis yielded six significant components with a 94 % of the variance explained and the leading patterns of favorable weather conditions for the development of the phenomenon were obtained. A zonda/non-zonda indicator c can be estimated by a logistic multiple regressions depending on the PCA component loadings, determining a zonda probability index \\widehat{c} calculable from T and Td profiles and it depends on the climatological features of the region. The index showed 74.7 % efficiency. The same analysis was performed by adding surface values of T and Td from Mendoza Aero station increasing the index efficiency to 87.8 %. The results revealed four significantly correlated PCs with a major improvement in differentiating zonda cases and a reducing of the uncertainty interval.

  4. Mass transfer in fuel cells. [electron microscopy of components, thermal decomposition of Teflon, water transport, and surface tension of KOH solutions

    Science.gov (United States)

    Walker, R. D., Jr.

    1973-01-01

    Results of experiments on electron microscopy of fuel cell components, thermal decomposition of Teflon by thermogravimetry, surface area and pore size distribution measurements, water transport in fuel cells, and surface tension of KOH solutions are described.

  5. Middle components of the auditory evoked response in bilateral temporal lobe lesions. Report on a patient with auditory agnosia

    DEFF Research Database (Denmark)

    Parving, A; Salomon, G; Elberling, Claus

    1980-01-01

    An investigation of the middle components of the auditory evoked response (10--50 msec post-stimulus) in a patient with auditory agnosia is reported. Bilateral temporal lobe infarctions were proved by means of brain scintigraphy, CAT scanning, and regional cerebral blood flow measurements...... that the middle components cannot be generated exclusively, if at all, in the primary auditory cortex, located in the temporal lobe. Furthermore, the responses are found to be of neurogenic origin according to the methodological procedure applied....

  6. Modelling Earth's surface topography: decomposition of the static and dynamic components

    DEFF Research Database (Denmark)

    Guerri, Mattia; Cammarano, Fabio; Tackley, Paul J.

    2016-01-01

    topography maps and perform instantaneous mantle flow modelling to calculate the dynamic topography. We explore the effects of proposed mantle 1-D viscosities and also test a 3D pressure- and temperature-dependent viscosity model. We find that the patterns of residual and dynamic topography are robust.......19). The correlation slightly improves when considering only the very long-wavelength components of the maps (average = ∼0.23). We therefore conclude that a robust determination of dynamic topography is not feasible since current uncertainties affecting crustal density, mantle density and mantle viscosity are still......Contrasting results on the magnitude of the dynamic component of topography motivate us to analyse the sources of uncertainties affecting long wavelength topography modelling. We obtain a range of mantle density structures from thermo-chemical interpretation of available seismic tomography models...

  7. Application of response surface techniques to helicopter rotor blade optimization procedure

    Science.gov (United States)

    Henderson, Joseph Lynn; Walsh, Joanne L.; Young, Katherine C.

    1995-01-01

    In multidisciplinary optimization problems, response surface techniques can be used to replace the complex analyses that define the objective function and/or constraints with simple functions, typically polynomials. In this work a response surface is applied to the design optimization of a helicopter rotor blade. In previous work, this problem has been formulated with a multilevel approach. Here, the response surface takes advantage of this decomposition and is used to replace the lower level, a structural optimization of the blade. Problems that were encountered and important considerations in applying the response surface are discussed. Preliminary results are also presented that illustrate the benefits of using the response surface.

  8. Principal component analysis of the cytokine and chemokine response to human traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Adel Helmy

    Full Text Available There is a growing realisation that neuro-inflammation plays a fundamental role in the pathology of Traumatic Brain Injury (TBI. This has led to the search for biomarkers that reflect these underlying inflammatory processes using techniques such as cerebral microdialysis. The interpretation of such biomarker data has been limited by the statistical methods used. When analysing data of this sort the multiple putative interactions between mediators need to be considered as well as the timing of production and high degree of statistical co-variance in levels of these mediators. Here we present a cytokine and chemokine dataset from human brain following human traumatic brain injury and use principal component analysis and partial least squares discriminant analysis to demonstrate the pattern of production following TBI, distinct phases of the humoral inflammatory response and the differing patterns of response in brain and in peripheral blood. This technique has the added advantage of making no assumptions about the Relative Recovery (RR of microdialysis derived parameters. Taken together these techniques can be used in complex microdialysis datasets to summarise the data succinctly and generate hypotheses for future study.

  9. Atmospheric components of the surface energy budget over young sea ice: Results from the N-ICE2015 campaign

    Science.gov (United States)

    Walden, Von P.; Hudson, Stephen R.; Cohen, Lana; Murphy, Sarah Y.; Granskog, Mats A.

    2017-08-01

    The Norwegian young sea ice campaign obtained the first measurements of the surface energy budget over young, thin Arctic sea ice through the seasonal transition from winter to summer. This campaign was the first of its kind in the North Atlantic sector of the Arctic. This study describes the atmospheric and surface conditions and the radiative and turbulent heat fluxes over young, thin sea ice. The shortwave albedo of the snow surface ranged from about 0.85 in winter to 0.72-0.80 in early summer. The near-surface atmosphere was typically stable in winter, unstable in spring, and near neutral in summer once the surface skin temperature reached 0°C. The daily average radiative and turbulent heat fluxes typically sum to negative values (-40 to 0 W m-2) in winter but then transition toward positive values of up to nearly +60 W m-2 as solar radiation contributes significantly to the surface energy budget. The sensible heat flux typically ranges from +20-30 W m-2 in winter (into the surface) to negative values between 0 and -20 W m-2 in spring and summer. A winter case study highlights the significant effect of synoptic storms and demonstrates the complex interplay of wind, clouds, and heat and moisture advection on the surface energy components over sea ice in winter. A spring case study contrasts a rare period of 24 h of clear-sky conditions with typical overcast conditions and highlights the impact of clouds on the surface radiation and energy budgets over young, thin sea ice.

  10. Advanced Response Surface Modeling of Ares I Roll Control Jet Aerodynamic Interactions

    Science.gov (United States)

    Favaregh, Noah M.

    2010-01-01

    The Ares I rocket uses roll control jets. These jets have aerodynamic implications as they impinge on the surface and protuberances of the vehicle. The jet interaction on the body can cause an amplification or a reduction of the rolling moment produced by the jet itself, either increasing the jet effectiveness or creating an adverse effect. A design of experiments test was planned and carried out using computation fluid dynamics, and a subsequent response surface analysis ensued on the available data to characterize the jet interaction across the ascent portion of the Ares I flight envelope. Four response surface schemes were compared including a single response surface covering the entire design space, separate sector responses that did not overlap, continuously overlapping surfaces, and recursive weighted response surfaces. These surfaces were evaluated on traditional statistical metrics as well as visual inspection. Validation of the recursive weighted response surface was performed using additionally available data at off-design point locations.

  11. Response Surface Modeling Tool Suite, Version 1.x

    Energy Technology Data Exchange (ETDEWEB)

    2016-07-05

    The Response Surface Modeling (RSM) Tool Suite is a collection of three codes used to generate an empirical interpolation function for a collection of drag coefficient calculations computed with Test Particle Monte Carlo (TPMC) simulations. The first code, "Automated RSM", automates the generation of a drag coefficient RSM for a particular object to a single command. "Automated RSM" first creates a Latin Hypercube Sample (LHS) of 1,000 ensemble members to explore the global parameter space. For each ensemble member, a TPMC simulation is performed and the object drag coefficient is computed. In the next step of the "Automated RSM" code, a Gaussian process is used to fit the TPMC simulations. In the final step, Markov Chain Monte Carlo (MCMC) is used to evaluate the non-analytic probability distribution function from the Gaussian process. The second code, "RSM Area", creates a look-up table for the projected area of the object based on input limits on the minimum and maximum allowed pitch and yaw angles and pitch and yaw angle intervals. The projected area from the look-up table is used to compute the ballistic coefficient of the object based on its pitch and yaw angle. An accurate ballistic coefficient is crucial in accurately computing the drag on an object. The third code, "RSM Cd", uses the RSM generated by the "Automated RSM" code and the projected area look-up table generated by the "RSM Area" code to accurately compute the drag coefficient and ballistic coefficient of the object. The user can modify the object velocity, object surface temperature, the translational temperature of the gas, the species concentrations of the gas, and the pitch and yaw angles of the object. Together, these codes allow for the accurate derivation of an object's drag coefficient and ballistic coefficient under any conditions with only knowledge of the object's geometry and mass.

  12. Human platelet glycoprotein Ia. One component is only expressed on the surface of activated platelets and may be a granule constituent

    International Nuclear Information System (INIS)

    Bienz, D.; Clemetson, K.J.

    1989-01-01

    Glycoprotein Ia (GP Ia) is a relatively minor component of human blood platelets thought to be a receptor involved in collagen-induced platelet activation. However, some difficulties exist with the definition of this glycoprotein. The expression of GP Ia on resting (prostacyclin analogue-treated) and thrombin-activated platelets was compared by surface labeling with 125 I-lactoperoxidase. Intact platelets or platelets solubilized in sodium dodecyl sulfate were labeled with periodate/[ 3 H]NaBH 4 . Analysis on two-dimensional isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels showed that GP Ia is very poorly labeled in resting platelets. After activation a new spot (GP Ia*) appears with the same relative molecular mass as GP Ia under reducing conditions. GP Ia and Ia* can be clearly separated by two-dimensional nonreduced/reduced gel electrophoresis. Therefore, two glycoproteins which have been termed GP Ia exist in platelets with similar molecular weight and pI under reducing conditions. One of these (GP Ia*) is only surface-labeled when platelets are activated, indicating that it is only exposed on the surface of activated platelets. Supernatant from activated platelets contains this glycoprotein as well as other granule components. This glycoprotein is missing in platelets from two patients with collagen-response defects

  13. Determining the impact of urban components on land surface temperature of Istanbul by using remote sensing indices.

    Science.gov (United States)

    Bektaş Balçik, Filiz

    2014-02-01

    For the past 60 years, Istanbul has been experiencing an accelerated urban expansion. This urban expansion is leading to the replacement of natural surfaces by various artificial materials. This situation has a critical impact on the environment due to the alteration of heat energy balance. In this study, the effect upon the urban heat island (UHI) of Istanbul was analyzed using 2009 dated Landsat 5 Thematic Mapper (TM) data. An Index Based Built-up Index (IBI) was used to derive artificial surfaces in the study area. To produce the IBI index, Soil-Adjusted Vegetation Index, Normalized Difference Built-up Index, and Modified Normalized Difference Water Index were calculated. Land surface temperature (LST) distribution was derived from Landsat 5 TM images using a mono-window algorithm. In addition, 24 transects were selected, and different regression models were applied to explore the correlation between LST and IBI index. The results show that artificial surfaces have a positive exponential relationship with LST rather than a simple linear one. An ecological evaluation index of the region was calculated to explore the impact of both the vegetated land and the artificial surfaces on the UHI. Therefore, the quantitative relationship of urban components (artificial surfaces, vegetation, and water) and LST was examined using multivariate statistical analysis, and the correlation coefficient was obtained as 0.829. This suggested that the areas with a high rate of urbanization will accelerate the rise of LST and UHI in Istanbul.

  14. Mutualism and impacts of global change: response of an important and neglected component of the biodiversity

    International Nuclear Information System (INIS)

    Hossaert-Mckey, M.

    2007-01-01

    We are studying the impact of global change on two obligate species-specific insect-plant mutualisms. Our approach combines correlative methods (examining spatial patterns of genetic diversity in populations of pairs of mutualists, to examine their responses to past climate change) and experiments (studying responses of plant partners to CO 2 fertilization). Mutualisms function because the partners have contrasting and complementary biological traits, so that a service implying only a low cost to one partner may confer a great benefit to the other. Because they can lead mutualist partners to respond differently to rapid ecological change, the biological differences that are fundamental to mutualisms may also make them vulnerable. Imbalances thereby introduced can disrupt the functioning of the mutualism. By comparing two strongly contrasting systems-fig/wasp pollination mutualisms and ant-plant protection mutualisms-we aim to characterize the diversity of responses of mutualisms to global change. By identifying points in common, we also aim to propose robust generalizations about the response to global change of obligate, specific mutualisms, an important and neglected component of tropical biodiversity. Our results show that the two mutualisms studied differ greatly in their response to Pleistocene and Holocene climatic fluctuations. Fig/wasp systems show little spatial genetic differentiation, indicating that the great dispersal capacities of both figs and their pollinating wasps resulted in maintenance of high effective population sizes throughout cycles of climatic and vegetation change. In contrast, limited dispersal capacity of both ant and plant partners has resulted in greater impact of climatic fluctuations on ant/plant protection mutualisms: species-distribution patterns suggest restriction of the system to refugia, and strong spatial genetic structure indicates widespread bottlenecks during fragmentation and expansion. Alternate contraction and expansion

  15. Experimental investigation of surface determination process on multi-material components for dimensional computed tomography

    DEFF Research Database (Denmark)

    Borges de Oliveira, Fabrício; Stolfi, Alessandro; Bartscher, Markus

    2016-01-01

    and suitable surface determination settings, limits a better acceptance of CT as a CMS. Moreover, standard CT users are subject to the algorithms and boundary conditions implied by the use of commercial analysis software. In this context, this paper is concerned with the experimental evaluation...... of the influence of surface determination process on multi-material measurements, using functions available in the commercial CT data analysis software Volume Graphics VGStudio Max 2.2.6. Calibrated step gauges made of different materials, i.e. PEEK, PPS, and Al were used as reference standards. The step gauges...... were assembled in such a way as to have different multi-material X-ray absorption ratios. Comparative measurements of mono-material assemblies were performed as well. Different segmentation processes were considered (e.g. ISO-50%, local threshold, region growing, etc.), patch-based bidirectional length...

  16. SURFACE FILMS TO SUPPRESS FIELD EMISSION IN HIGH-POWER MICROWAVE COMPONENTS

    Energy Technology Data Exchange (ETDEWEB)

    Hirshfield, Jay l

    2014-02-07

    Results are reported on attempts to reduce the RF breakdown probability on copper accelerator structures by applying thin surface films that could suppress field emission of electrons. Techniques for application and testing of copper samples with films of metals with work functions higher than copper are described, principally for application of platinum films, since platinum has the second highest work function of any metal. Techniques for application of insulating films are also described, since these can suppress field emission and damage on account of dielectric shielding of fields at the copper surface, and on account of the greater hardness of insulating films, as compared with copper. In particular, application of zirconium oxide films on high-field portions of a 11.424 GHz SLAC cavity structure for breakdown tests are described.

  17. Transient temperature response of in-vessel components due to pulsed operation in tokamak fusion experimental reactor (FER)

    International Nuclear Information System (INIS)

    Minato, Akio; Tone, Tatsuzo

    1985-12-01

    A transient temperature response of the in-vessel components (first wall, blanket, divertor/limiter and shielding) surrounding plasma in Tokamak Fusion Experimental Reactor (FER) has been analysed. Transient heat load during start up/shut down and pulsed operation cycles causes the transient temperature response in those components. The fatigue lifetime of those components significantly depends upon the resulting cyclic thermal stress. The burn time affects the temperature control in the solid breeder (Li 2 O) and also affects the thermo-mechanical design of the blanket and shielding which are constructed with thick structure. In this report, results of the transient temperature response obtained by the heat transfer and conduction analyses for various pulsed operation scenarios (start up, shut down, burn and dwell times) have been investigated in view of thermo-mechanical design of the in-vessel components. (author)

  18. The complex dynamics of the seasonal component of USA's surface temperature

    Directory of Open Access Journals (Sweden)

    A. Vecchio

    2010-10-01

    Full Text Available The dynamics of the climate system has been investigated by analyzing the complex seasonal oscillation of monthly averaged temperatures recorded at 1167 stations covering the whole USA. We found the presence of an orbit-climate relationship on time scales remarkably shorter than the Milankovitch period {related to the nutational forcing}. The relationship manifests itself through occasional destabilization of the phase of the seasonal component due to the local changing of balance between direct insolation and the net energy received by the Earth. Quite surprisingly, we found that the local intermittent dynamics is modulated by a periodic component of about 18.6 yr due to the nutation of the Earth, which represents the main modulation of the Earth's precession. The global effect in the last century results in a cumulative phase-shift of about 1.74 days towards earlier seasons, in agreement with the phase shift expected from the Earth's precession. The climate dynamics of the seasonal cycle can be described through a nonlinear circle-map, indicating that the destabilization process can be associated to intermittent transitions from quasi-periodicity to chaos.

  19. Response surface optimization of electrochemical treatment of textile dye wastewater

    International Nuclear Information System (INIS)

    Koerbahti, Bahadir K.

    2007-01-01

    The electrochemical treatment of textile dye wastewater containing Levafix Blue CA, Levafix Red CA and Levafix Yellow CA reactive dyes was studied on iron electrodes in the presence of NaCl electrolyte in a batch electrochemical reactor. The wastewater was synthetically prepared in relatively high dye concentrations between 400 mg/L and 2000 mg/L. The electrochemical treatment of textile dye wastewater was optimized using response surface methodology (RSM), where current density and electrolyte concentration were to be minimized while dye removal and turbidity removal were maximized at 28 deg. C reaction temperature. Optimized conditions under specified cost driven constraints were obtained for the highest desirability at 6.7 mA/cm 2 , 5.9 mA/cm 2 and 5.4 mA/cm 2 current density and 3.1 g/L, 2.5 g/L and 2.8 g/L NaCl concentration for Levafix Blue CA, Levafix Red CA and Levafix Yellow CA reactive textile dyes, respectively

  20. Response surface analysis to improve dispersed crude oil biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Zahed, Mohammad A.; Aziz, Hamidi A.; Mohajeri, Leila [School of Civil Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang (Malaysia); Isa, Mohamed H. [Civil Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Perak (Malaysia)

    2012-03-15

    In this research, the bioremediation of dispersed crude oil, based on the amount of nitrogen and phosphorus supplementation in the closed system, was optimized by the application of response surface methodology and central composite design. Correlation analysis of the mathematical-regression model demonstrated that a quadratic polynomial model could be used to optimize the hydrocarbon bioremediation (R{sup 2} = 0.9256). Statistical significance was checked by analysis of variance and residual analysis. Natural attenuation was removed by 22.1% of crude oil in 28 days. The highest removal on un-optimized condition of 68.1% were observed by using nitrogen of 20.00 mg/L and phosphorus of 2.00 mg/L in 28 days while optimization process exhibited a crude oil removal of 69.5% via nitrogen of 16.05 mg/L and phosphorus 1.34 mg/L in 27 days therefore optimization can improve biodegradation in shorter time with less nutrient consumption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Optimization of vibratory welding process parameters using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Pravin Kumar; Kumar, S. Deepak; Patel, D.; Prasad, S. B. [National Institute of Technology Jamshedpur, Jharkhand (India)

    2017-05-15

    The current investigation was carried out to study the effect of vibratory welding technique on mechanical properties of 6 mm thick butt welded mild steel plates. A new concept of vibratory welding technique has been designed and developed which is capable to transfer vibrations, having resonance frequency of 300 Hz, into the molten weld pool before it solidifies during the Shielded metal arc welding (SMAW) process. The important process parameters of vibratory welding technique namely welding current, welding speed and frequency of the vibrations induced in molten weld pool were optimized using Taguchi’s analysis and Response surface methodology (RSM). The effect of process parameters on tensile strength and hardness were evaluated using optimization techniques. Applying RSM, the effect of vibratory welding parameters on tensile strength and hardness were obtained through two separate regression equations. Results showed that, the most influencing factor for the desired tensile strength and hardness is frequency at its resonance value, i.e. 300 Hz. The micro-hardness and microstructures of the vibratory welded joints were studied in detail and compared with those of conventional SMAW joints. Comparatively, uniform and fine grain structure has been found in vibratory welded joints.

  2. Combined approach based on principal component analysis and canonical discriminant analysis for investigating hyperspectral plant response

    Directory of Open Access Journals (Sweden)

    Anna Maria Stellacci

    2012-07-01

    Full Text Available Hyperspectral (HS data represents an extremely powerful means for rapidly detecting crop stress and then aiding in the rational management of natural resources in agriculture. However, large volume of data poses a challenge for data processing and extracting crucial information. Multivariate statistical techniques can play a key role in the analysis of HS data, as they may allow to both eliminate redundant information and identify synthetic indices which maximize differences among levels of stress. In this paper we propose an integrated approach, based on the combined use of Principal Component Analysis (PCA and Canonical Discriminant Analysis (CDA, to investigate HS plant response and discriminate plant status. The approach was preliminary evaluated on a data set collected on durum wheat plants grown under different nitrogen (N stress levels. Hyperspectral measurements were performed at anthesis through a high resolution field spectroradiometer, ASD FieldSpec HandHeld, covering the 325-1075 nm region. Reflectance data were first restricted to the interval 510-1000 nm and then divided into five bands of the electromagnetic spectrum [green: 510-580 nm; yellow: 581-630 nm; red: 631-690 nm; red-edge: 705-770 nm; near-infrared (NIR: 771-1000 nm]. PCA was applied to each spectral interval. CDA was performed on the extracted components to identify the factors maximizing the differences among plants fertilised with increasing N rates. Within the intervals of green, yellow and red only the first principal component (PC had an eigenvalue greater than 1 and explained more than 95% of total variance; within the ranges of red-edge and NIR, the first two PCs had an eigenvalue higher than 1. Two canonical variables explained cumulatively more than 81% of total variance and the first was able to discriminate wheat plants differently fertilised, as confirmed also by the significant correlation with aboveground biomass and grain yield parameters. The combined

  3. Structural features of the two-component system LisR/LisK suggests multiple responses for the adaptation and survival of Listeria monocytogenes

    Directory of Open Access Journals (Sweden)

    Nelson Enrique Arenas Suarez

    2013-08-01

    Full Text Available Here, we characterized the structure of the two-component regulatory system, LisR/LisK, in Listeria monocytogenes. To predict the structure of both proteins and the relationship between them, we employed several bioinformatic tools and databases. Based on our results, LisK protein is embedded in the cell membrane and its modular composition (HAMP, histidine kinase and ATPase domains is associated with its autophosphorylation (His-266. A stimulus-response likely determines the sequential signal propagation from the bacterial cell surface to its cytoplasmic components. According to our results, LisR is a cytoplasmic protein with a receptor domain (homologous to CheY that comprises a phosphoacceptor residue (Asp-52 and a DNA-binding domain, which may allow the transmission of a specific transcriptional response. LisR/LisK has been experimentally characterized both biochemically andfunctionally in other Bacilli pathophysiology; our structure-function approach may facilitate the design of suitable inhibitors.

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

    Science.gov (United States)

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

    2018-02-27

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

  5. Plasma surface reflectance spectroscopy for non-invasive and continuous monitoring of extracellular component of blood

    Science.gov (United States)

    Sakota, Daisuke; Takatani, Setsuo

    2012-04-01

    To achieve the quantitative optical non-invasive diagnosis of blood during extracorporeal circulation therapies, the instrumental technique to extract extracellular spectra from whole blood was developed. In the circuit, the continuous blood flow was generated by a centrifugal blood pump. The oxygen saturation was maintained 100% by an oxygenator. The developed glass optical flow cell was attached to the outlet tubing of the oxygenator. The halogen lamp including the light from 400 to 900 nm wavelength was used for the light source. The light was guided into an optical fiber. The light emitted by the fiber was collimated and emitted to the flow cell flat surface at the incident angle of 45 degrees. The light just reflected on the boundary between inner surface of the flow cell and plasma at 45 degrees was detected by the detection fiber. The detected light was analyzed by a spectral photometer. The obtained spectrum from 400 to 600nm wavelength was not changed with respect to the hematocrit. In contrast, the signal in the spectral range was changed when the plasma free hemoglobin increased. By using two spectral range, 505+/-5 nm and 542.5+/-2.5 nm, the differential spectrum was correlated with the free hemoglobin at R2=0.99. On the other hand, as for the hematocrit, the differential spectrum was not correlated at R2=0.01. Finally, the plasma free hemoglobin was quantified with the accuracy of 22+/-19mg/dL. The result shows that the developed plasma surface reflectance spectroscopy (PSRS) can extract the plasma spectrum from flowing whole blood.

  6. Stress corrosion cracking of Ni-based alloys in PWR primary water. Component surface control; Corrosion sous contrainte des alliages a base nickel en milieu primaire des reacteurs a eaux pressurisee. Maitrise de la surface des composants

    Energy Technology Data Exchange (ETDEWEB)

    Foucault, M. [AREVA, Centre Technique Framatome ANP, Dept. Corrosion Chimie, 71 - Le Creusot (France)

    2004-06-01

    In the PWR plant primary circuit, FRAMATOME-ANP uses several nickel-base alloys or austenitic stainless steels for the manufacture of safety components. The experience feedback of the last twenty years allows us to point out the major role played by the surface state of the components in their life duration. In this paper, we present two examples of problems encountered and solved by a surface study and the definition and implementation of a process for the surface control of the repair components. Then, we propose some ideas about the present needs in terms of analysis methods to improve the surface knowledge and the control of the manufactured components. (author)

  7. Enhanced osteoblast response to electrical discharge machining surface.

    Science.gov (United States)

    Otsuka, Fukunaga; Kataoka, Yu; Miyazaki, Takashi

    2012-01-01

    The purpose of this study is to investigate the surface characteristics and biocompatibility of titanium (Ti) surfaces modified by wire electrical discharge machining (EDM). EDM surface characteristics were evaluated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thin-film X-ray diffractometry (XRD) and contact angle measurements. MC3T3-E1 cell morphology, attachment and proliferation, as well as analysis of osteoblastic gene expressions, on machined surfaces and EDM surfaces were also evaluated. EDM surfaces exhibited high super hydrophilicity, due to high surface energy. XPS and XRD revealed that a passive oxide layer with certain developing thickness onto. EDM surfaces promoted cell attachment, but restrained proliferation. Counted cell numbers increased significantly on the machined surfaces as compared to the EDM surfaces. Real-time PCR analyses showed significantly higher relative mRNA expression levels of osteoblastic genes (ALP, osteocalcin, Runx2, Osterix) in cells cultured on the EDM surfaces as compared to cells cultured on the machined surfaces.

  8. Antibacterial performance of polypropylene nonwoven fabric wound dressing surfaces containing passive and active components

    Science.gov (United States)

    Xin, Zhirong; Du, Shanshan; Zhao, Chunyu; Chen, Hao; Sun, Miao; Yan, Shunjie; Luan, Shifang; Yin, Jinghua

    2016-03-01

    A growing number of wound dressing-related nosocomial infections necessitate the development of novel antibacterial strategies. Herein, polypropylene non-woven fabric (PPNWF) was facilely modified with passive and active antibacterial components, namely photografting polymerization both N-Vinyl-2-pyrrolidone (NVP) and glycidyl methacrylate (GMA) monomers, and the introduction of guanidine polymer through the reaction between active amino groups and epoxy groups. The modified samples were confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), respectively. Water contact angle measurement, antibacterial test, platelet and red blood cell adhesion were used to evaluate the hydrophilicity, antibacterial properties and hemocompatibility of the samples. It was found that the antibacterial properties were obviously enhanced, meanwhile significantly suppressing platelet and red blood cell adhesion after the above modification. This PPNWF samples that possess antifouling and antimicrobial properties, have great potential in wound dressing applications.

  9. Wear surface damage of a Stainless Steel EN 3358 aeronautical component subjected to sliding

    Directory of Open Access Journals (Sweden)

    Ferdinando Felli

    2013-01-01

    Full Text Available The present paper describes the failure analysis of an aircraft component subjected to several episodes of in service failure, resulted in loss of the aircraft safety. Modern aircrafts are provided with mechanical systems which have the task to open not pressurized hatches during landing. The components of such systems are subject to considerable mechanical stresses in harsh environment (presence of moisture and pollutants, significant and sudden temperature variations. The system is constituted by a sliding piston, a related nipple and by a locking system consisting of 4 steel spheres which are forced into a countersink machined on the piston when the hatches is open. The whole system is activated by a preloaded spring. The machined parts, nipple and piston, are made of EN3358 steel (X3CrNiMo13-8-2, a precipitation hardening stainless steel with very low content of carbon often used in the aerospace. The samples provided by the manufacturer present different types of damage all referable to phenomena relative to the sliding of the piston inside the nipple. The present paper describes the different damage observed and the microstructure of the material, then are reported the results obtained from the characterization of the material of the samples by means of optical and electronic microscopy, carried out to define the mechanisms involved in the system seizure. In order to define the primary cause of failure and to propose solutions to be adopted, also analyzing the criticality of using this PH stainless steel for this application, the results of different tests were compared with system design and working data.

  10. GEOEPIDERM – AN ECOLOGICAL CONCEPT THAT INTEGRATES SOIL COVER WITH ASSOCIATED LAND SURFACE COMPONENTS

    Directory of Open Access Journals (Sweden)

    I. Munteanu

    2008-10-01

    Full Text Available Based on the new concept of the “Epiderm of the Earth” introduced by the 2006 edition of the WRB-SR, the idea of “geoepiderm” has been developed. Besides its holistic meaning, by including both soil and non-soil materials found in the first 2 meters of the land surface, the term “geoepiderm” has a strong ecological sense, by suggesting similarity with the skin of the living organisms, as such, this concept is fully concordant with that of “Gaia” (Living Earth developed by James Lovelock. According to the main pedo-ecological characteristics of the soil and not soil coverings from the earth surface, ten kinds (classes of ‘geoepiderms” have been identified:1 – Protoderma (Entiderma– the primitive (emerging geoepiderm (mainly non-soil materials; five main subtypes: a Regoderma, b Leptoderma, c Areniderma, d Fluviderma and e Gleyoderma, were identified;2 – Cryoderma (Geliderma – geoepiderm of cold, mainly artic and subartic, regions with mean annual soil temperature <00C (often with perennial frozen subsoil - permafrost:3 – Arididerma – geoepiderm of arid regions and salt affected lands with limited or scarce available moisture; two subtypes: a Desertiderma, b Saliderma4 – Inceptiderma (or Juvenilederma – with 2 subtypes: a Cambiderma – a young (incipiently developed geoepiderm and b Andiderma, geoepiderm developed in volcanic materials;5 – Euderma – nutrient rich geoepiderm with two main subtypes: a Cherniderma (or Molliderma and b Luviderma (or Alfiderma;6 – Oligoderma – geoepiderm with low macro-nutrient and weatherable minerals content with 2 subtypes: a Podziderma (or Spodiderma and b Acriderma (or Ultiderma;7 – Ferriderma (Oxiderma or Senilederma – geoepiderm strongly weathered and with iron and aluminium hydroxides enrichment and low weatherable minerals reserve;8 – Vertiderma (Contractilederma – Contractile geoepiderm, developed from swelling clays;9 – Histoderma (Organiderma

  11. Effects of size reduction on deformation, microstructure, and surface roughness of micro components for micro metal injection molding

    Science.gov (United States)

    Liu, Lin; Wang, Xin-da; Li, Xiang; Qi, Xiao-tong; Qu, Xuan-hui

    2017-09-01

    The fabrication of 17-4PH micro spool mandrils by micro metal injection molding was described here. The effects of size reduction on deformation, microstructure and surface roughness were studied by comparing a ϕ500 μm micro post and a ϕ1.7 mm cylinder after debinding and sintering. Experimental results show that slumping of the micro posts occurred due to a dramatic increase in outlet vapor pressure initiated at the thermal degradation onset temperature and the moment of gravity. Asymmetrical stress distribution within the micro component formed during the cooling stage may cause warping. Prior solvent debinding and adjustment in a thermal debinding scheme were useful for preventing the deformation of the micro components. Smaller grain size and higher micro hardness due to impeded grain growth were observed for the micro posts compared with the ϕ1.7 mm cylinder. Surface roughness increased with distance from the gate of the micro spool mandril due to melt front advancement during mold filling and the ensuing pressure distribution. At each position, surface roughness was dictated by injection molding and increased slightly after sintering.

  12. Formulation and Evaluation of Cookies Containing Germinated Pigeon Pea, Fermented Sorghum and Cocoyam Flour Blends using Mixture Response Surface Methodology

    OpenAIRE

    Laura C. Okpala; Eric C. Okoli

    2011-01-01

    Cookies were produced from blends of germinated pigeon pea, fermented sorghum and cocoyam flours. The study was carried out to evaluate the effects of varying the proportions of these components on the sensory and protein quality of the cookies. The sensory attributes studied were colour, taste, texture, crispiness and general acceptability while the protein quality indices were Biological Value (BV) and Net Protein Utilization (NPU). Mixture response surface methodology was used to model the...

  13. Optimization of Chitinase Production by Bacillus pumilus Using Plackett-Burman Design and Response Surface Methodology.

    Science.gov (United States)

    Tasharrofi, Noshin; Adrangi, Sina; Fazeli, Mehdi; Rastegar, Hossein; Khoshayand, Mohammad Reza; Faramarzi, Mohammad Ali

    2011-01-01

    A soil bacterium capable of degrading chitin on chitin agar plates was isolated and identified as Bacillus pumilus isolate U5 on the basis of 16S rDNA sequence analysis. In order to optimize culture conditions for chitinase production by this bacterium, a two step approach was employed. First, the effects of several medium components were studied using the Plackett-Burman design. Among various components tested, chitin and yeast extract showed positive effect on enzyme production while MgSO4 and FeSO4 had negative effect. However, the linear model proved to be insufficient for determining the optimum levels for these components due to a highly significant curvature effect. In the second step, Box-Behnken response surface methodology was used to determine the optimum values. It was noticed that a quadratic polynomial equation fitted he experimental data appropriately. The optimum concentrations for chitin, yeast extract, MgSO4 and FeSO4 were found to be 4.76, 0.439, 0.0055 and 0.019 g/L, respectively, with a predicted value of chitinase production of 97.67 U/100 mL. Using this statistically optimized medium, the practical chitinase production reached 96.1 U/100 mL.

  14. Application of Plackett-Burman design and response surface methodology to achieve exponential growth for aggregated shipworm bacterium.

    Science.gov (United States)

    Ahuja, S K; Ferreira, G M; Moreira, A R

    2004-03-20

    Here we report the successful implementation of the Plackett-Burman multifactorial design to screen the limiting components for growth and subsequent use of the response surface methodology (RSM) to design a medium that supported exponential growth of the aggregated morphology of the shipworm bacterium, Teredinobacter turnirae. The results obtained with the help of Plackett-Burman design indicated limitations of three components in the growth medium, MnCl2.4H2O, Na2CO3, and K2HPO4. The concentrations of these three components were further optimized using RSM. By increasing the concentrations of the above-mentioned components by 4-fold, 12-fold, and 12-fold, respectively, it became possible to achieve exponential growth of the culture. Copyright 2004 Wiley Periodicals, Inc.

  15. First accelerator test of vacuum components with laser-engineered surfaces for electron-cloud mitigation

    Science.gov (United States)

    Calatroni, Sergio; Garcia-Tabares Valdivieso, Elisa; Neupert, Holger; Nistor, Valentin; Perez Fontenla, Ana Teresa; Taborelli, Mauro; Chiggiato, Paolo; Malyshev, Oleg; Valizadeh, Reza; Wackerow, Stefan; Zolotovskaya, Svetlana A.; Gillespie, W. Allan; Abdolvand, Amin

    2017-11-01

    Electron cloud mitigation is an essential requirement for high-intensity proton circular accelerators. Among other solutions, laser engineered surface structures (LESS) present the advantages of having potentially a very low secondary electron yield (SEY) and allowing simple scalability for mass production. Two copper liners with LESS have been manufactured and successfully tested by monitoring the electron cloud current in a dipole magnet in the SPS accelerator at CERN during the 2016 run. In this paper we report on these results as well as the detailed experiments carried out on samples—such as the SEY and topography studies—which led to an optimized treatment in view of the SPS test and future possible use in the HL-LHC.

  16. Modeling Earth's surface topography: decomposition of the static and dynamic components

    Science.gov (United States)

    Guerri, M.; Cammarano, F.; Tackley, P. J.

    2017-12-01

    Isolating the portion of topography supported by mantle convection, the so-called dynamic topography, would give us precious information on vigor and style of the convection itself. Contrasting results on the estimate of dynamic topography motivate us to analyse the sources of uncertainties affecting its modeling. We obtain models of mantle and crust density, leveraging on seismic and mineral physics constraints. We use the models to compute isostatic topography and residual topography maps. Estimates of dynamic topography and associated synthetic geoid are obtained by instantaneous mantle flow modeling. We test various viscosity profiles and 3D viscosity distributions accounting for inferred lateral variations in temperature. We find that the patterns of residual and dynamic topography are robust, with an average correlation coefficient of 0.74 and 0.71, respectively. The amplitudes are however poorly constrained. For the static component, the considered lithospheric mantle density models result in topographies that differ, on average, 720 m, with peaks reaching 1.7 km. The crustal density models produce variations in isostatic topography averaging 350 m, with peaks of 1 km. For the dynamic component, we obtain peak-to-peak topography amplitude exceeding 3 km for all the tested mantle density and viscosity models. Such values of dynamic topography produce geoid undulations that are not in agreement with observations. Assuming chemical heterogeneities in the lower mantle, in correspondence with the LLSVPs (Large Low Shear wave Velocity Provinces), helps to decrease the amplitudes of dynamic topography and geoid, but reduces the correlation between synthetic and observed geoid. The correlation coefficients between the residual and dynamic topography maps is always less than 0.55. In general, our results indicate that, i) current knowledge of crust density, mantle density and mantle viscosity is still limited, ii) it is important to account for all the various

  17. A novel design procedure for tractor clutch fingers by using optimization and response surface methods

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Oguz; Karpat, Fatih; Yuce, Celalettin; Kaya, Necmettin; Yavuz, Nurettin [Uludag University, Gorukle (Turkmenistan); Sen, Hasan [Valeo A. S., Bursa (Turkmenistan)

    2016-06-15

    This paper presents a methodology for re-designing a failed tractor transmission component subjected to cyclic loading. Unlike other vehicles, tractors cope with tough working conditions. Thus, it is necessary to re-design components by using modern optimization techniques. To extend their service life, we present a design methodology for a failed tractor clutch power take-off finger. The finger was completely re-designed using topology and shape optimization approach. Stress-life based fatigue analyses were performed. Shape optimization and response surface methodology were conducted to obtain optimum dimensions of the finger. Two design parameters were selected for the design of experiment method and 15 cases were analyzed. By using design of the experiment method, three responses were obtained: Maximum stresses, mass, and displacement depending on the selected the design parameters. After solving the optimization problem, we achieved a maximum stress and mass reduction of 14% and 6%, respectively. The stiffness was improved up to 31.6% compared to the initial design.

  18. Microencapsulation of Theobroma cacao L. waste extract: optimization using response surface methodology.

    Science.gov (United States)

    Gabbay Alves, Taís Vanessa; Silva da Costa, Russany; Aliakbarian, Bahar; Casazza, Alessandro Alberto; Perego, Patrizia; Carréra Silva Júnior, José Otávio; Ribeiro Costa, Roseane Maria; Converti, Attilio

    2017-03-01

    The cocoa extract (Theobroma cacao L.) has a significant amount of polyphenols (TP) with potent antioxidant activity (AA). This study aims to optimise microencapsulation of the extract of cocoa waste using chitosan and maltodextrin. Microencapsulation tests were performed according to a Box-Behnken factorial design, and the results were evaluated by response surface methodology with temperature, maltodextrin concentration (MD) and extract flowrate (EF) as independent variables, and the fraction of encapsulated TP, TP encapsulation yield, AA, yield of drying and solubility index as responses. The optimum conditions were: inlet temperature of 170 °C, MD of 5% and EF of 2.5 mL/min. HPLC analysis identified epicatechin as the major component of both the extract and microparticles. TP release was faster at pH 3.5 than in water. These results as a whole suggest that microencapsulation was successful and the final product can be used as a nutrient source for aquatic animal feed. Highlights Microencapsulation is optimised according to a factorial design of the Box-Behnken type. Epicatechin is the major component of both the extract and microcapsules. The release of polyphenols from microcapsules is faster at pH 3.5 than in water.

  19. Process optimization of microencapsulation of curcumin in γ-polyglutamic acid using response surface methodology.

    Science.gov (United States)

    Ko, Wen-Ching; Chang, Chao-Kai; Wang, Hsiu-Ju; Wang, Shian-Jen; Hsieh, Chang-Wei

    2015-04-01

    The aim of this study was to develop an optimal microencapsulation method for an oil-soluble component (curcumin) using γ-PGA. The results show that Span80 significantly enhances the encapsulation efficiency (EE) of γ-Na(+)-PGA microcapsules. Therefore, the effects of γ-Na(+)-PGA, curcumin and Span80 concentration on EE of γ-Na(+)-PGA microcapsules were studied by means of response surface methodology (RSM). It was found that the optimal microencapsulation process is achieved by using γ-Na(+)-PGA 6.05%, curcumin 15.97% and Span80 0.61% with a high EE% (74.47 ± 0.20%). Furthermore, the models explain 98% of the variability in the responses. γ-Na(+)-PGA seems to be a good carrier for the encapsulation of curcumin. In conclusion, this simple and versatile approach can potentially be applied to the microencapsulation of various oil-soluble components for food applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Effects of fuel components and combustion particle physicochemical properties on toxicological responses of lung cells.

    Science.gov (United States)

    Jaramillo, Isabel C; Sturrock, Anne; Ghiassi, Hossein; Woller, Diana J; Deering-Rice, Cassandra E; Lighty, JoAnn S; Paine, Robert; Reilly, Christopher; Kelly, Kerry E

    2018-03-21

    The physicochemical properties of combustion particles that promote lung toxicity are not fully understood, hindered by the fact that combustion particles vary based on the fuel and combustion conditions. Real-world combustion-particle properties also continually change as new fuels are implemented, engines age, and engine technologies evolve. This work used laboratory-generated particles produced under controlled combustion conditions in an effort to understand the relationship between different particle properties and the activation of established toxicological outcomes in human lung cells (H441 and THP-1). Particles were generated from controlled combustion of two simple biofuel/diesel surrogates (methyl decanoate and dodecane/biofuel-blended diesel (BD), and butanol and dodecane/alcohol-blended diesel (AD)) and compared to a widely studied reference diesel (RD) particle (NIST SRM2975/RD). BD, AD, and RD particles exhibited differences in size, surface area, extractable chemical mass, and the content of individual polycyclic aromatic hydrocarbons (PAHs). Some of these differences were directly associated with different effects on biological responses. BD particles had the greatest surface area, amount of extractable material, and oxidizing potential. These particles and extracts induced cytochrome P450 1A1 and 1B1 enzyme mRNA in lung cells. AD particles and extracts had the greatest total PAH content and also caused CYP1A1 and 1B1 mRNA induction. The RD extract contained the highest relative concentration of 2-ring PAHs and stimulated the greatest level of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNFα) cytokine secretion. Finally, AD and RD were more potent activators of TRPA1 than BD, and while neither the TRPA1 antagonist HC-030031 nor the antioxidant N-acetylcysteine (NAC) affected CYP1A1 or 1B1 mRNA induction, both inhibitors reduced IL-8 secretion and mRNA induction. These results highlight that differences in fuel and combustion conditions

  1. Response Surface Methods For Spatially-Resolved Optical Measurement Techniques

    Science.gov (United States)

    Danehy, P. M.; Dorrington, A. A.; Cutler, A. D.; DeLoach, R.

    2003-01-01

    Response surface methods (or methodology), RSM, have been applied to improve data quality for two vastly different spatially-resolved optical measurement techniques. In the first application, modern design of experiments (MDOE) methods, including RSM, are employed to map the temperature field in a direct-connect supersonic combustion test facility at NASA Langley Research Center. The laser-based measurement technique known as coherent anti-Stokes Raman spectroscopy (CARS) is used to measure temperature at various locations in the combustor. RSM is then used to develop temperature maps of the flow. Even though the temperature fluctuations at a single point in the flowfield have a standard deviation on the order of 300 K, RSM provides analytic fits to the data having 95% confidence interval half width uncertainties in the fit as low as +/- 30 K. Methods of optimizing future CARS experiments are explored. The second application of RSM is to quantify the shape of a 5-meter diameter, ultra-lightweight, inflatable space antenna at NASA Langley Research Center. Photogrammetry is used to simultaneously measure the shape of the antenna at approximately 500 discrete spatial locations. RSM allows an analytic model to be developed that describes the shape of the majority of the antenna with an uncertainty of 0.4 mm, with 95% confidence. This model would allow a quantitative comparison between the actual shape of the antenna and the original design shape. Accurately determining this shape also allows confident interpolation between the measured points. Such a model could, for example, be used for ray tracing of radio-frequency waves up to 95 GHz. to predict the performance of the antenna.

  2. Optimization of cocoa nib roasting based on sensory properties and colour using response surface methodology

    Directory of Open Access Journals (Sweden)

    D.M.H. A.H. Farah

    2012-05-01

    Full Text Available Roasting of cocoa beans is a critical stage for development of its desirable flavour, aroma and colour. Prior to roasting, cocoa bean may taste astringent, bitter, acidy, musty, unclean, nutty or even chocolate-like, depends on the bean sources and their preparations. After roasting, the bean possesses a typical intense cocoa flavour. The Maillard or non-enzymatic browning reactions is a very important process for the development of cocoa flavor, which occurs primarily during the roasting process and it has generally been agreed that the main flavor components, pyrazines formation is associated within this reaction involving amino acids and reducing sugars. The effect of cocoa nib roasting conditions on sensory properties and colour of cocoa beans were investigated in this study. Roasting conditions in terms of temperature ranged from 110 to 160OC and time ranged from 15 to 40 min were optimized by using Response Surface Methodology based on the cocoa sensory characteristics including chocolate aroma, acidity, astringency, burnt taste and overall acceptability. The analyses used 9- point hedonic scale with twelve trained panelist. The changes in colour due to the roasting condition were also monitored using chromameter. Result of this study showed that sensory quality of cocoa liquor increased with the increase in roasting time and temperature up to 160OC and up to 40 min, respectively. Based on the Response Surface Methodology, the optimised operating condition for the roaster was at temperature of 127OC and time of 25 min. The proposed roasting conditions were able to produce superior quality cocoa beans that will be very useful for cocoa manufactures.Key words : Cocoa, cocoa liquor, flavour, aroma, colour, sensory characteristic, response surface methodology.

  3. Surface Composition of the Non-Ice Component on Icy Satellites and Ring Particles in the Saturn System

    Science.gov (United States)

    Clark, R. N.; Pearson, N.; Perlman, Z. S.; Bradley, E. T.; Hendrix, A.; Cuzzi, J. N.; Cruikshank, D. P.; Filacchione, G.; Nicholson, P. D.; Hedman, M. M.; Brown, R. H.; Buratti, B. J.; Baines, K. H.; Sotin, C.; Nelson, R.

    2013-12-01

    Saturn's icy satellites and ring particle surfaces have long been known to be composed mostly of frozen water. However, all surfaces show an absorption due to a non-water-ice component whose identity has not been well understood. In the near infrared, water ice has strong absorptions which limit detectability of other trace components. Similarly, at wavelengths less than about 0.18 microns, water is very absorbing. However, in the ~0.2 to ~1 micron range, water ice has low absorption and trace components are readily detected. Classical interpretations of the UV absorber and dark material on outer Solar System satellites have been varying amounts of tholins and carbon. However, tholins have spectral structure not seen in the icy spectra in the Saturn System. Many silicates also have UV spectral structure that reject them from contributing significantly to the observed spectral signatures. We have constructed a new UV spectrometer and a new environment chamber for studying the spectral properties of materials from 0.1 to 15 microns. In our survey of the spectral properties of materials so far, we find that small amounts of metallic iron and iron oxides in the icy surfaces are compatible with and can explain the UV, visible and near-infrared spectra of icy surfaces in the Saturn system (0.12 to 5.1 microns) using data from the Cassini UltraViolet Imaging Spectrograph (UVIS) and the Visual and Infrared Mapping Spectrometer (VIMS). The wide range of observed UV-NIR (0.1-5 micron) spectral signatures provide strong constraints on composition and grain size distribution, including grain sizes of the ice. Spectra of the Saturnian rings and icy satellites indicate they have a large range of ice grain sizes, from tens of microns to sub-micron. Sub-micron ice grains create unusual spectral properties, which are seen in the spectra of the rings and satellites of Saturn and on satellites further out in the Solar System. Clark et al. (2012, Icarus v218, p831) showed that VIMS

  4. Physical stability assessment and sensory optimization of a dairy-free emulsion using response surface methodology.

    Science.gov (United States)

    Granato, Daniel; de Castro, I Alves; Ellendersen, L Souza Neves; Masson, M Lucia

    2010-04-01

    Desserts made with soy cream, which are oil-in-water emulsions, are widely consumed by lactose-intolerant individuals in Brazil. In this regard, this study aimed at using response surface methodology (RSM) to optimize the sensory attributes of a soy-based emulsion over a range of pink guava juice (GJ: 22% to 32%) and soy protein (SP: 1% to 3%). WHC and backscattering were analyzed after 72 h of storage at 7 degrees C. Furthermore, a rating test was performed to determine the degree of liking of color, taste, creaminess, appearance, and overall acceptability. The data showed that the samples were stable against gravity and storage. The models developed by RSM adequately described the creaminess, taste, and appearance of the emulsions. The response surface of the desirability function was used successfully in the optimization of the sensory properties of dairy-free emulsions, suggesting that a product with 30.35% GJ and 3% SP was the best combination of these components. The optimized sample presented suitable sensory properties, in addition to being a source of dietary fiber, iron, copper, and ascorbic acid.

  5. Processing optimization of probiotic yogurt containing glucose oxidase using response surface methodology.

    Science.gov (United States)

    Cruz, A G; Faria, J A F; Walter, E H M; Andrade, R R; Cavalcanti, R N; Oliveira, C A F; Granato, D

    2010-11-01

    Exposure to oxygen may induce a lack of functionality of probiotic dairy foods because the anaerobic metabolism of probiotic bacteria compromises during storage the maintenance of their viability to provide benefits to consumer health. Glucose oxidase can constitute a potential alternative to increase the survival of probiotic bacteria in yogurt because it consumes the oxygen permeating to the inside of the pot during storage, thus making it possible to avoid the use of chemical additives. This research aimed to optimize the processing of probiotic yogurt supplemented with glucose oxidase using response surface methodology and to determine the levels of glucose and glucose oxidase that minimize the concentration of dissolved oxygen and maximize the Bifidobacterium longum count by the desirability function. Response surface methodology mathematical models adequately described the process, with adjusted determination coefficients of 83% for the oxygen and 94% for the B. longum. Linear and quadratic effects of the glucose oxidase were reported for the oxygen model, whereas for the B. longum count model an influence of the glucose oxidase at the linear level was observed followed by the quadratic influence of glucose and quadratic effect of glucose oxidase. The desirability function indicated that 62.32 ppm of glucose oxidase and 4.35 ppm of glucose was the best combination of these components for optimization of probiotic yogurt processing. An additional validation experiment was performed and results showed acceptable error between the predicted and experimental results. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. In Vitro Optimization of Enzymes Involved in Precorrin-2 Synthesis Using Response Surface Methodology.

    Science.gov (United States)

    Fang, Huan; Dong, Huina; Cai, Tao; Zheng, Ping; Li, Haixing; Zhang, Dawei; Sun, Jibin

    2016-01-01

    In order to maximize the production of biologically-derived chemicals, kinetic analyses are first necessary for predicting the role of enzyme components and coordinating enzymes in the same reaction system. Precorrin-2 is a key precursor of cobalamin and siroheme synthesis. In this study, we sought to optimize the concentrations of several molecules involved in precorrin-2 synthesis in vitro: porphobilinogen synthase (PBGS), porphobilinogen deaminase (PBGD), uroporphyrinogen III synthase (UROS), and S-adenosyl-l-methionine-dependent urogen III methyltransferase (SUMT). Response surface methodology was applied to develop a kinetic model designed to maximize precorrin-2 productivity. The optimal molar ratios of PBGS, PBGD, UROS, and SUMT were found to be approximately 1:7:7:34, respectively. Maximum precorrin-2 production was achieved at 0.1966 ± 0.0028 μM/min, agreeing with the kinetic model's predicted value of 0.1950 μM/min. The optimal concentrations of the cofactor S-adenosyl-L-methionine (SAM) and substrate 5-aminolevulinic acid (ALA) were also determined to be 200 μM and 5 mM, respectively, in a tandem-enzyme assay. By optimizing the relative concentrations of these enzymes, we were able to minimize the effects of substrate inhibition and feedback inhibition by S-adenosylhomocysteine on SUMT and thereby increase the production of precorrin-2 by approximately five-fold. These results demonstrate the effectiveness of kinetic modeling via response surface methodology for maximizing the production of biologically-derived chemicals.

  7. Optimization of ultrasonic-assisted preparation of dietary fiber from corn pericarp using response surface methodology.

    Science.gov (United States)

    Wang, Anna; Wu, Ligen; Li, Xiulin

    2013-09-01

    Corn pericarp, which is an industrial waste of corn starch production, is an important source of dietary fiber in cereals, with claimed health benefits. However, they used to be discarded or utilized as animal feed. The application of pre-ultrasound treatment is critical for achieving rapid preparation of desired components from plant materials and for preserving structural and molecular properties of these compounds. Ultrasonic-assisted preparation was used to produce dietary fiber from corn pericarp using response surface methodology. The optimal particle size of corn pericarp (mesh size 40), the ratio of liquid to solid (25 mL g⁻¹), ultrasonic power (180 W) and ultrasonic time (80 min) were determined based on response surface methodology analysis. The interaction effects of particle size of corn pericarp and ultrasonic time had a highlysignificant effect on the yield of dietary fiber, and a significant effect was shown by ultrasonic power and ultrasonic time. The maximum yield of dietary fiber was 86.84%, which agreed closely with the predicted value. Using ultrasonic-assisted preparation, it may be possible to enhance the yield of dietary fiber from corn pericarp. © 2013 Society of Chemical Industry.

  8. Stenotrophomonas maltophilia PhoP, a Two-Component Response Regulator, Involved in Antimicrobial Susceptibilities.

    Directory of Open Access Journals (Sweden)

    Ming-Che Liu

    Full Text Available Stenotrophomonas maltophilia, a gram-negative bacterium, has increasingly emerged as an important nosocomial pathogen. It is well-known for resistance to a variety of antimicrobial agents including cationic antimicrobial polypeptides (CAPs. Resistance to polymyxin B, a kind of CAPs, is known to be controlled by the two-component system PhoPQ. To unravel the role of PhoPQ in polymyxin B resistance of S. maltophilia, a phoP mutant was constructed. We found MICs of polymyxin B, chloramphenicol, ampicillin, gentamicin, kanamycin, streptomycin and spectinomycin decreased 2-64 fold in the phoP mutant. Complementation of the phoP mutant by the wild-type phoP gene restored all of the MICs to the wild type levels. Expression of PhoP was shown to be autoregulated and responsive to Mg2+ levels. The polymyxin B and gentamicin killing tests indicated that pretreatment of low Mg2+ can protect the wild-type S. maltophilia from killing but not phoP mutant. Interestingly, we found phoP mutant had a decrease in expression of SmeZ, an efflux transporter protein for aminoglycosides in S. maltophilia. Moreover, phoP mutant showed increased permeability in the cell membrane relative to the wild-type. In summary, we demonstrated the two-component regulator PhoP of S. maltophilia is involved in antimicrobial susceptibilities and low Mg2+ serves as a signal for triggering the pathway. Both the alteration in membrane permeability and downregulation of SmeZ efflux transporter in the phoP mutant contributed to the increased drug susceptibilities of S. maltophilia, in particular for aminoglycosides. This is the first report to describe the role of the Mg2+-sensing PhoP signaling pathway of S. maltophilia in regulation of the SmeZ efflux transporter and in antimicrobial susceptibilities. This study suggests PhoPQ TCS may serve as a target for development of antimicrobial agents against multidrug-resistant S. maltophilia.

  9. [Optimization for supercritical CO2 extraction with response surface methodology of Prunus armeniaca oil].

    Science.gov (United States)

    Chen, Fei-Fei; Wu, Yan; Ge, Fa-Huan

    2012-03-01

    To optimize the extraction conditions of Prunus armeniaca oil by Supercritical CO2 extraction and identify its components by GC-MS. Optimized of SFE-CO extraction by response surface methodology and used GC-MS to analysis Prunus armeniaca oil compounds. Established the model of an equation for the extraction rate of Prunus armeniaca oil by supercritical CO2 extraction, and the optimal parameters for the supercritical CO2 extraction determined by the equation were: the extraction pressure was 27 MPa, temperature was 39 degrees C, the extraction rate of Prunus armeniaca oil was 44.5%. 16 main compounds of Prunus armeniaca oil extracted by supercritical CO2 were identified by GC-MS, unsaturated fatty acids were 92.6%. This process is simple, and can be used for the extraction of Prunus armeniaca oil.

  10. Optimisation of steam distillation extraction oil from onion by response surface methodology and its chemical composition.

    Science.gov (United States)

    Wang, Zhao Dan; Li, Li Hua; Xia, Hui; Wang, Feng; Yang, Li Gang; Wang, Shao Kang; Sun, Gui Ju

    2018-01-01

    Oil extraction from onion was performed by steam distillation. Response surface methodology was applied to evaluate the effects of ratio of water to raw material, extraction time, zymolysis temperature and distillation times on yield of onion oil. The maximum extraction yield (1.779%) was obtained as following conditions: ratio of water to raw material was 1, extraction time was 2.5 h, zymolysis temperature was 36° and distillation time was 2.6 h. The experimental values agreed well with those predicted by regression model. The chemical composition of extracted onion oil under the optimum conditions was analysed by gas chromatography-mass spectrometry technology. The results showed that sulphur compounds, like alkanes, sulphide, alkenes, ester and alcohol, were the major components of onion oil.

  11. Response surface methodology for the optimization of sludge solubilization by ultrasonic pre-treatment

    Science.gov (United States)

    Zheng, Mingyue; Zhang, Xiaohui; Lu, Peng; Cao, Qiguang; Yuan, Yuan; Yue, Mingxing; Fu, Yiwei; Wu, Libin

    2018-02-01

    The present study examines the optimization of the ultrasonic pre-treatment conditions with response surface experimental design in terms of sludge disintegration efficiency (solubilisation of organic components). Ultrasonic pre-treatment for the maximum solubilization with residual sludge enhanced the SCOD release. Optimization of the ultrasonic pre-treatment was conducted through a Box-Behnken design (three variables, a total of 17 experiments) to determine the effects of three independent variables (power, residence time and TS) on COD solubilization of sludge. The optimal COD was obtained at 17349.4mg/L, when the power was 534.67W, the time was 10.77, and TS was 2%, while the SE of this condition was 28792J/kg TS.

  12. Physicochemical characterization of engineered nanoparticles under physiological conditions: effect of culture media components and particle surface coating.

    Science.gov (United States)

    Fatisson, Julien; Quevedo, Ivan R; Wilkinson, Kevin J; Tufenkji, Nathalie

    2012-03-01

    The use of engineered nanoparticles (ENPs) in commercial products has increased substantially over the last few years. Some research has been conducted in order to determine whether or not such materials are cytotoxic, but questions remain regarding the role that physiological media and sera constituents play in ENP aggregation or stabilization. In this study, several characterization methods were used to evaluate the particle size and surface potential of 6 ENPs suspended in a number of culture media and in the presence of different culture media constituents. Dynamic light scattering (DLS) and fluorescence correlation spectroscopy (FCS) were employed for size determinations. Results were interpreted on the basis of ENP surface potentials evaluated from particle electrophoretic mobilities (EPM). Measurements made after 24h of incubation at 37°C showed that the cell culture medium constituents had only moderate impact on the physicochemical properties of the ENP, although incubation in bovine serum albumin destabilized the colloidal system. In contrast, most of the serum proteins increased colloidal stabilization. Moreover, the type of ENP surface modification played a significant role in ENP behavior whereby the complexity of interactions between the ENPs and the medium components generally decreased with increasing complexity of the particle surface. This investigation emphasizes the importance of ENP characterization under conditions that are representative of cell culture media or physiological conditions for improved assessments of nanoparticle cytotoxicity. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Functionalization of PDMS modified and plasma activated two-component polyurethane coatings by surface attachment of enzymes

    International Nuclear Information System (INIS)

    Kreider, Alexej; Richter, Katharina; Sell, Stephan; Fenske, Mandus; Tornow, Christian; Stenzel, Volkmar; Grunwald, Ingo

    2013-01-01

    This article describes a new strategy for coupling the enzyme horseradish peroxidase to a two-component polyurethane (2C-PUR) coating. A stable polymer conjugate was achieved by combining the enzyme and the 2C-PUR coating which was modified with poly(dimethylsiloxane) (PDMS), located at the surface. An atmospheric pressure plasma jet system was used to convert alkyl groups from the PDMS into polar silanol functionalities. This conversion was proven by X-ray photoelectron spectroscopy and dynamic contact angle measurements. In addition, the stability of the activated 2C-PUR surface containing silanol groups was determined by measuring the contact angle as a function of time. Compared to the non-modified 2C-PUR systems the one with PDMS displayed a higher stability over a time period over 28 h. In a silanization process the coating was treated with (3-aminopropyl) trimethoxysilane and the enzyme was subsequently immobilized to the coating via the cross linker glutaraldehyde to receive new biomimetic catalytic/enzymatic functions. The chemical immobilization (chemisorption) of the enzyme to the surface showed statistically significant higher biological activity as compared to references samples without using a cross linker (physisorption). The presented technique offers the opportunity to design new and smart multifunctional surface coatings which employ biomimetic capabilities.

  14. Laser Surface Treatment of Hydro and Thermal Power Plant Components and Their Coatings: A Review and Recent Findings

    Science.gov (United States)

    Mann, B. S.

    2015-11-01

    High-power diode laser (HPDL) surface modification of hydro and thermal power plant components is of the utmost importance to minimize their damages occurring due to cavitation erosion, water droplet erosion, and particle erosion (CE, WDE, and PE). Special emphasis is given on the HPDL surface treatment of martensitic and precipitate-hardened stainless steels, Ti6Al4V alloy, plasma ion nitro-carburized layers, high pressure high velocity oxy-fuel and twin-wire arc sprayed coatings. WDE test results of all these materials and coatings in `untreated' and `HPDL- treated at 1550 °C' conditions, up to 8.55 million cycles, are already available. Their WDE testing was further continued up to 10.43 million cycles. The X20Cr13 and X10CrNiMoV1222, the most common martensitic stainless steels used in hydro and thermal power plants, were HPDL surface treated at higher temperature (1650 °C) and their WDE test results were also obtained up to 10.43 million cycles. It is observed that the increased HPDL surface temperature from 1550 to 1650 °C has resulted in significant improvement in their WDE resistances because of increased martensitic (ά) phase at higher temperature. After conducting long-range WDE tests, the correlation of CE, WDE, and PE resistances of these materials and protective coatings with their mechanical properties such as fracture toughness and microhardness product, ultimate resilience, modified resilience, and ultimate modified resilience has been reviewed and discussed. One of the edges of a 500 MW low pressure steam turbine moving blade (X10CrNiMoV1222 stainless steel) was HPDL surface treated at 1550 °C and its radii of curvatures and deflections were measured. These were compared with the data available earlier from a flat rectangular sample of similar composition and identical HPDL surface temperature.

  15. Optimization of Coolant Technique Conditions for Machining A319 Aluminium Alloy Using Response Surface Method (RSM)

    Science.gov (United States)

    Zainal Ariffin, S.; Razlan, A.; Ali, M. Mohd; Efendee, A. M.; Rahman, M. M.

    2018-03-01

    Background/Objectives: The paper discusses about the optimum cutting parameters with coolant techniques condition (1.0 mm nozzle orifice, wet and dry) to optimize surface roughness, temperature and tool wear in the machining process based on the selected setting parameters. The selected cutting parameters for this study were the cutting speed, feed rate, depth of cut and coolant techniques condition. Methods/Statistical Analysis Experiments were conducted and investigated based on Design of Experiment (DOE) with Response Surface Method. The research of the aggressive machining process on aluminum alloy (A319) for automotive applications is an effort to understand the machining concept, which widely used in a variety of manufacturing industries especially in the automotive industry. Findings: The results show that the dominant failure mode is the surface roughness, temperature and tool wear when using 1.0 mm nozzle orifice, increases during machining and also can be alternative minimize built up edge of the A319. The exploration for surface roughness, productivity and the optimization of cutting speed in the technical and commercial aspects of the manufacturing processes of A319 are discussed in automotive components industries for further work Applications/Improvements: The research result also beneficial in minimizing the costs incurred and improving productivity of manufacturing firms. According to the mathematical model and equations, generated by CCD based RSM, experiments were performed and cutting coolant condition technique using size nozzle can reduces tool wear, surface roughness and temperature was obtained. Results have been analyzed and optimization has been carried out for selecting cutting parameters, shows that the effectiveness and efficiency of the system can be identified and helps to solve potential problems.

  16. Improvements to a Response Surface Thermal Model for Orion Mated to the International Space Station

    Science.gov (United States)

    Miller, StephenW.; Walker, William Q.

    2011-01-01

    This study is an extension of previous work to evaluate the applicability of Design of Experiments (DOE)/Response Surface Methodology to on-orbit thermal analysis. The goal was to determine if the methodology could produce a Response Surface Equation (RSE) that predicted the thermal model temperature results within +/-10 F. An RSE is a polynomial expression that can then be used to predict temperatures for a defined range of factor combinations. Based on suggestions received from the previous work, this study used a model with simpler geometry, considered polynomials up to fifth order, and evaluated orbital temperature variations to establish a minimum and maximum temperature for each component. A simplified Outer Mold Line (OML) thermal model of the Orion spacecraft was used in this study. The factors chosen were the vehicle's Yaw, Pitch, and Roll (defining the on-orbit attitude), the Beta angle (restricted to positive beta angles from 0 to 75), and the environmental constants (varying from cold to hot). All factors were normalized from their native ranges to a non-dimensional range from -1.0 to 1.0. Twenty-three components from the OML were chosen and the minimum and maximum orbital temperatures were calculated for each to produce forty-six responses for the DOE model. A customized DOE case matrix of 145 analysis cases was developed which used analysis points at the factor corners, mid-points, and center. From this data set, RSE s were developed which consisted of cubic, quartic, and fifth order polynomials. The results presented are for the fifth order RSE. The RSE results were then evaluated for agreement with the analytical model predictions to produce a +/-3(sigma) error band. Forty of the 46 responses had a +/-3(sigma) value of 10 F or less. Encouraged by this initial success, two additional sets of verification cases were selected. One contained 20 cases, the other 50 cases. These cases were evaluated both with the fifth order RSE and with the analytical

  17. The effect of surface plasmon resonance on optical response in ...

    Indian Academy of Sciences (India)

    By increasing the shell radius and therefore increasing the metal content the SPR at the outer surface shifts to higher energy and the weaker peak (at inner surface) shifts to lower energy. Also, depending on the metal shell materials SPR occurs in different energy regions and therefore can be tuned the SP frequency at ...

  18. Modeling the survival responses of a multi-component biofilm to environmental stress

    Science.gov (United States)

    Carles Brangarí, Albert; Manzoni, Stefano; Sanchez-Vila, Xavier; Fernàndez-Garcia, Daniel

    2017-04-01

    Biofilms are consortia of microorganisms embedded in self-produced matrices of biopolymers. The survival of such communities depends on their capacity to improve the environmental conditions of their habitat by mitigating, or even benefitting from some adverse external factors. The mechanisms by which the microbial habitat is regulated remain mostly unknown. However, many studies have reported physiological responses to environmental stresses that include the release of extracellular polymeric substances (EPS) and the induction of a dormancy state. A sound understanding of these capacities is required to enhance the knowledge of the microbial dynamics in soils and its potential role in the carbon cycle, with significant implications for the degradation of contaminants and the emission of greenhouse gases, among others. We present a numerical analysis of the dynamics of soil microbes and their responses to environmental stresses. The conceptual model considers a multi-component heterotrophic biofilm made up of active cells, dormant cells, EPS, and extracellular enzymes. Biofilm distribution and properties are defined at the pore-scale and used to determine nutrient availability and water saturation via feedbacks of biofilm on soil hydraulic properties. The pore space micro-habitat is modeled as a simplified pore-network of cylindrical tubes in which biofilms proliferate. Microbial compartments and most of the carbon fluxes are defined at the bulk level. Microbial processes include the synthesis, decay and detachment of biomass, the activation/deactivation of cells, and the release and reutilization of EPS. Results suggest that the release of EPS and the capacity to enter a dormant state offer clear evolutionary advantages in scenarios characterized by environmental stress. On the contrary, when the conditions are favorable, the diversion of carbon into the production of the aforementioned survival mechanisms does not confer any additional benefit and the population

  19. Dissecting Low Atmospheric Pressure Stress: Transcriptome Responses to the Components of Hypobaria in Arabidopsis [Experiment 2

    Data.gov (United States)

    National Aeronautics and Space Administration — Controlled hypobaria presents biology with an environment that is never encountered in terrestrial ecology yet the apparent components of hypobaria are stresses...

  20. Dissecting Low Atmospheric Pressure Stress: Transcriptome Responses to the Components of Hypobaria in Arabidopsis [Experiment 1

    Data.gov (United States)

    National Aeronautics and Space Administration — Controlled hypobaria presents biology with an environment that is never encountered in terrestrial ecology yet the apparent components of hypobaria are stresses...

  1. Histone Deacetylase 2 Is a Component of Influenza A Virus-Induced Host Antiviral Response.

    Science.gov (United States)

    Nagesh, Prashanth T; Hussain, Mazhar; Galvin, Henry D; Husain, Matloob

    2017-01-01

    Host cells produce variety of antiviral factors that create an antiviral state and target various stages of influenza A virus (IAV) life cycle to inhibit infection. However, IAV has evolved various strategies to antagonize those antiviral factors. Recently, we reported that a member of class I host histone deacetylases (HDACs), HDAC1 possesses an anti-IAV function. Herein, we provide evidence that HDAC2, another class I member and closely related to HDAC1 in structure and function, also possesses anti-IAV properties. In turn, IAV, like HDAC1, dysregulates HDAC2, mainly at the polypeptide level through proteasomal degradation to potentially minimize its antiviral effect. We found that IAV downregulated the HDAC2 polypeptide level in A549 cells in an H1N1 strain-independent manner by up to 47%, which was recovered to almost 100% level in the presence of proteasome-inhibitor MG132. A further knockdown in HDAC2 expression by up to 90% via RNA interference augmented the growth kinetics of IAV in A549 cells by more than four-fold after 24 h of infection. Furthermore, the knockdown of HDAC2 expression decreased the IAV-induced phosphorylation of the transcription factor, Signal Transducer and Activator of Transcription I (STAT1) and the expression of interferon-stimulated gene, viperin in infected cells by 41 and 53%, respectively. The role of HDAC2 in viperin expression was analogous to that of HDAC1, but it was not in the phosphorylation of STAT1. This indicated that, like HDAC1, HDAC2 is a component of IAV-induced host innate antiviral response and performs both redundant and non-redundant functions vis-a-vis HDAC1; however, IAV dysregulates them both in a redundant manner.

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

    Directory of Open Access Journals (Sweden)

    Ekaterina V. Filippova

    2018-02-01

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

  3. Expression of cellular components in granulomatous inflammatory response in Piaractus mesopotamicus model.

    Directory of Open Access Journals (Sweden)

    Wilson Gómez Manrique

    Full Text Available The present study aimed to describe and characterize the cellular components during the evolution of chronic granulomatous inflammation in the teleost fish pacus (P. mesopotamicus induced by Bacillus Calmette-Guerin (BCG, using S-100, iNOS and cytokeratin antibodies. 50 fish (120±5.0 g were anesthetized and 45 inoculated with 20 μL (40 mg/mL (2.0 x 10(6 CFU/mg and five inoculated with saline (0,65% into muscle tissue in the laterodorsal region. To evaluate the inflammatory process, nine fish inoculated with BCG and one control were sampled in five periods: 3rd, 7th, 14th, 21st and 33rd days post-inoculation (DPI. Immunohistochemical examination showed that the marking with anti-S-100 protein and anti-iNOS antibodies was weak, with a diffuse pattern, between the third and seventh DPI. From the 14th to the 33rd day, the marking became stronger and marked the cytoplasm of the macrophages. Positivity for cytokeratin was initially observed in the 14th DPI, and the stronger immunostaining in the 33rd day, period in which the epithelioid cells were more evident and the granuloma was fully formed. Also after the 14th day, a certain degree of cellular organization was observed, due to the arrangement of the macrophages around the inoculated material, with little evidence of edema. The arrangement of the macrophages around the inoculum, the fibroblasts, the lymphocytes and, in most cases, the presence of melanomacrophages formed the granuloma and kept the inoculum isolated in the 33rd DPI. The present study suggested that the granulomatous experimental model using teleost fish P. mesopotamicus presented a similar response to those observed in mammals, confirming its importance for studies of chronic inflammatory reaction.

  4. Histone Deacetylase 2 Is a Component of Influenza A Virus-Induced Host Antiviral Response

    Directory of Open Access Journals (Sweden)

    Prashanth T. Nagesh

    2017-07-01

    Full Text Available Host cells produce variety of antiviral factors that create an antiviral state and target various stages of influenza A virus (IAV life cycle to inhibit infection. However, IAV has evolved various strategies to antagonize those antiviral factors. Recently, we reported that a member of class I host histone deacetylases (HDACs, HDAC1 possesses an anti-IAV function. Herein, we provide evidence that HDAC2, another class I member and closely related to HDAC1 in structure and function, also possesses anti-IAV properties. In turn, IAV, like HDAC1, dysregulates HDAC2, mainly at the polypeptide level through proteasomal degradation to potentially minimize its antiviral effect. We found that IAV downregulated the HDAC2 polypeptide level in A549 cells in an H1N1 strain-independent manner by up to 47%, which was recovered to almost 100% level in the presence of proteasome-inhibitor MG132. A further knockdown in HDAC2 expression by up to 90% via RNA interference augmented the growth kinetics of IAV in A549 cells by more than four-fold after 24 h of infection. Furthermore, the knockdown of HDAC2 expression decreased the IAV-induced phosphorylation of the transcription factor, Signal Transducer and Activator of Transcription I (STAT1 and the expression of interferon-stimulated gene, viperin in infected cells by 41 and 53%, respectively. The role of HDAC2 in viperin expression was analogous to that of HDAC1, but it was not in the phosphorylation of STAT1. This indicated that, like HDAC1, HDAC2 is a component of IAV-induced host innate antiviral response and performs both redundant and non-redundant functions vis-a-vis HDAC1; however, IAV dysregulates them both in a redundant manner.

  5. Analysis and Modeling of the Galvanic Skin Response Spontaneous Component in the context of Intelligent Biofeedback Systems Development

    Science.gov (United States)

    Unakafov, A.

    2009-01-01

    The paper presents an approach to galvanic skin response (GSR) spontaneous component analysis and modeling. In the study a classification of biofeedback training methods is given, importance of intelligent methods development is shown. The INTENS method, which is perspective for intellectualization, is presented. An important problem of biofeedback training method intellectualization - estimation of the GSR spontaneous component - is solved in the main part of the work. Its main characteristics are described; results of GSR spontaneous component modeling are shown. Results of small research of an optimum material for GSR probes are presented.

  6. Principal Component Analysis in Grey Based Taguchi Method for Optimization of Multiple Surface Quality Characteristics of 6061-T4 Aluminum in CNC End Milling

    Science.gov (United States)

    Datta, Saurav; Routara, Bharat Chandra; Bandyopadhyay, Asish; Mahapatra, Siba Sankar

    2011-01-01

    The present study highlights a multi-objective optimization problem by applying Principal Component Analysis (PCA) coupled with grey based Taguchi method through a case study in CNC end milling of 6061-T4 Aluminum. The study aimed at evaluating the best process environment which could simultaneously satisfy multiple requirements of surface quality. In view of the fact, that traditional Taguchi method cannot solve a multi-objective optimization problem; to overcome this limitation, grey relation theory has been coupled with Taguchi method. Furthermore, to follow the basic assumption of Taguchi method i.e. quality attributes should be uncorrelated or independent; which is not always satisfied in practical situation. To overcome this shortcoming the study applied Principal Component analysis to eliminate response correlation and to evaluate independent or uncorrelated quality indices called Principal Components which were aggregated to compute an overall quality index denoted as overall grey relational grade which was optimized (minimized) finally. The study combined PCA and grey based Taguchi method for predicting optimal setting. Optimal result was verified through confirmatory test.

  7. Brain responses to emotional stimuli during breath holding and hypoxia: an approach based on the independent component analysis.

    Science.gov (United States)

    Menicucci, Danilo; Artoni, Fiorenzo; Bedini, Remo; Pingitore, Alessandro; Passera, Mirko; Landi, Alberto; L'Abbate, Antonio; Sebastiani, Laura; Gemignani, Angelo

    2014-11-01

    Voluntary breath holding represents a physiological model of hypoxia. It consists of two phases of oxygen saturation dynamics: an initial slow decrease (normoxic phase) followed by a rapid drop (hypoxic phase) during which transitory neurological symptoms as well as slight impairment of integrated cerebral functions, such as emotional processing, can occur. This study investigated how breath holding affects emotional processing. To this aim we characterized the modulation of event-related potentials (ERPs) evoked by emotional-laden pictures as a function of breath holding time course. We recorded ERPs during free breathing and breath holding performed in air by elite apnea divers. We modeled brain responses during free breathing with four independent components distributed over different brain areas derived by an approach based on the independent component analysis (ICASSO). We described ERP changes during breath holding by estimating amplitude scaling and time shifting of the same components (component adaptation analysis). Component 1 included the main EEG features of emotional processing, had a posterior localization and did not change during breath holding; component 2, localized over temporo-frontal regions, was present only in unpleasant stimuli responses and decreased during breath holding, with no differences between breath holding phases; component 3, localized on the fronto-central midline regions, showed phase-independent breath holding decreases; component 4, quite widespread but with frontal prevalence, decreased in parallel with the hypoxic trend. The spatial localization of these components was compatible with a set of processing modules that affects the automatic and intentional controls of attention. The reduction of unpleasant-related ERP components suggests that the evaluation of aversive and/or possibly dangerous situations might be altered during breath holding.

  8. A comparison of response spectrum and direct integration analysis methods as applied to a nuclear component support structure

    International Nuclear Information System (INIS)

    Bryan, B.J.; Flanders, H.E. Jr.

    1992-01-01

    Seismic qualification of Class I nuclear components is accomplished using a variety of analytical methods. This paper compares the results of time history dynamic analyses of a heat exchanger support structure using response spectrum and time history direct integration analysis methods. Dynamic analysis is performed on the detailed component models using the two methods. A nonlinear elastic model is used for both the response spectrum and direct integration methods. A nonlinear model which includes friction and nonlinear springs, is analyzed using time history input by direct integration. The loads from the three cases are compared

  9. Quantifying the Molecular-Scale Aqueous Response to the Mica Surface

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, Arushi [Department; Pfaendtner, Jim [Department; Senior; Chun, Jaehun [Physical; Mundy, Christopher J. [Physical; Affiliate

    2017-08-09

    Modeling assembly at surfaces requires a multi-scale understanding of the interactions between solutes, solvents, and surfaces. We investigated the solvent response (water structure and orientation) to a dielectric surface (mica) using density functional theory. A different water structure is engendered by replacing naturally-occurring surface ions (K+) with H3O+ and validates classical models for the mica surface (CLAYFF). The detailed microscopic response of water to mica can be used as input into continuum models for the total interactions between two mica surfaces supporting a strong correlation between physicochemical phenomena at different scales.

  10. Osteoblast response to zirconia surfaces with different topographies

    Energy Technology Data Exchange (ETDEWEB)

    Herath, H.M.T.U. [Department of Medical Laboratory Science, Faculty of Allied Health Sciences, University of Peradeniya (Sri Lanka); Di Silvio, L. [Guy' s, King' s and St Thomas' Medical and Dental Institute, King' s College London, London SE1 9RT (United Kingdom); Evans, J.R.G., E-mail: j.r.g.evans@ucl.ac.uk [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

    2015-12-01

    Zirconia-3 mol% yttria ceramics were prepared with as-sintered, abraded, polished, and porous surfaces in order to explore the attachment, proliferation and differentiation of osteoblast-like cells. After modification, all surfaces were heated to 600 °C to extinguish traces of organic contamination. All surfaces supported cell attachment, proliferation and differentiation but the surfaces with grain boundary grooves or abraded grooves provided conditions for enhanced initial cell attachment. Nevertheless, overall cell proliferation and total DNA were highest on the polished surface. Zirconia sintered at a lower temperature (1300 °C vs. 1450 °C) had open porosity and presented reduced proliferation as assessed by alamarBlue™ assay, possibly because the openness of the pores prevented cells developing a local microenvironment. All cells retained the typical polygonal morphology of osteoblast-like cells with variations attributable to the underlying surface notably alignment along the grooves of the abraded surface. - Highlights: • Biocompatibility of chemically identical, topologically different ZrO{sub 2} was tested. • ZrO{sub 2} promoted cell adhesion, proliferation, differentiation and nodule formation. • Proliferation was high on polished ZrO{sub 2} but initial recruitment was high on abraded ZrO{sub 2}. • With open porosity, proliferation was low; cells cannot establish a microenvironment.

  11. Responses of Surface Ozone Air Quality to Anthropogenic Nitrogen Deposition

    Science.gov (United States)

    Zhang, L.; Zhao, Y.; Tai, A. P. K.; Chen, Y.; Pan, Y.

    2017-12-01

    Human activities have substantially increased atmospheric deposition of reactive nitrogen to the Earth's surface, inducing unintentional effects on ecosystems with complex environmental and climate consequences. One consequence remaining unexplored is how surface air quality might respond to the enhanced nitrogen deposition through surface-atmosphere exchange. We combine a chemical transport model (GEOS-Chem) and a global land model (Community Land Model) to address this issue with a focus on ozone pollution in the Northern Hemisphere. We consider three processes that are important for surface ozone and can be perturbed by addition of atmospheric deposited nitrogen: emissions of biogenic volatile organic compounds (VOCs), ozone dry deposition, and soil nitrogen oxide (NOx) emissions. We find that present-day anthropogenic nitrogen deposition (65 Tg N a-1 to the land), through enhancing plant growth (represented as increases in vegetation leaf area index (LAI) in the model), could increase surface ozone from increased biogenic VOC emissions, but could also decrease ozone due to higher ozone dry deposition velocities. Meanwhile, deposited anthropogenic nitrogen to soil enhances soil NOx emissions. The overall effect on summer mean surface ozone concentrations show general increases over the globe (up to 1.5-2.3 ppbv over the western US and South Asia), except for some regions with high anthropogenic NOx emissions (0.5-1.0 ppbv decreases over the eastern US, Western Europe, and North China). We compare the surface ozone changes with those driven by the past 20-year climate and historical land use changes. We find that the impacts from anthropogenic nitrogen deposition can be comparable to the climate and land use driven surface ozone changes at regional scales, and partly offset the surface ozone reductions due to land use changes reported in previous studies. Our study emphasizes the complexity of biosphere-atmosphere interactions, which can have important

  12. A dynamic monitoring approach for the surface morphology evolution measurement of plasma facing components by means of speckle interferometry

    Science.gov (United States)

    Wang, Hongbei; Cui, Xiaoqian; Feng, Chunlei; Li, Yuanbo; Zhao, Mengge; Luo, Guangnan; Ding, Hongbin

    2017-11-01

    Plasma Facing Components (PFCs) in a magnetically confined fusion plasma device will be exposed to high heat load and particle fluxes, and it would cause PFCs' surface morphology to change due to material erosion and redeposition from plasma wall interactions. The state of PFCs' surface condition will seriously affect the performance of long-pulse or steady state plasma discharge in a tokamak; it will even constitute an enormous threat to the operation and the safety of fusion plasma devices. The PFCs' surface morphology evolution measurement could provide important information about PFCs' real-time status or damage situation and it would help to a better understanding of the plasma wall interaction process and mechanism. Meanwhile through monitoring the distribution of dust deposition in a tokamak and providing an upper limit on the amount of loose dust, the PFCs' surface morphology measurement could indirectly contribute to keep fusion operational limits and fusion device safety. Aiming at in situ dynamic monitoring PFCs' surface morphology evolution, a laboratory experimental platform DUT-SIEP (Dalian University of Technology-speckle interferometry experimental platform) based on the speckle interferometry technique has been constructed at Dalian University of Technology (DUT) in China. With directional specific designing and focusing on the real detection condition of EAST (Experimental Advanced Superconducting Tokamak), the DUT-SIEP could realize a variable measurement range, widely increased from 0.1 μm to 300 μm, with high spatial resolution (adopted from EAST has been measured, and the feasibility and reliability of this new experimental platform have been demonstrated.

  13. Surface Plasmon Polaritons on Silver Gratings for Optimal SERS Response.

    Czech Academy of Sciences Publication Activity Database

    Kalachyova, Y.; Mareš, D.; Lyutakov, O.; Koštejn, Martin; Lapčák, L.; Svorčík, V.

    2015-01-01

    Roč. 119, č. 17 (2015), s. 9506-9512 ISSN 1932-7447 Institutional support: RVO:67985858 Keywords : enhanced raman-scattering * metallic surface * relief gratings Subject RIV: CC - Organic Chemistry Impact factor: 4.509, year: 2015

  14. Osteoblast cell response to surface-modified carbon nanotubes

    International Nuclear Information System (INIS)

    Zhang Faming; Weidmann, Arne; Nebe, J. Barbara; Burkel, Eberhard

    2012-01-01

    In order to investigate the interaction of cells with modified multi-walled carbon nanotubes (MWCNTs) for their potential biomedical applications, the MWCNTs were chemically modified with carboxylic acid groups (–COOH), polyvinyl alcohol (PVA) polymer and biomimetic apatite on their surfaces. Additionally, human osteoblast MG-63 cells were cultured in the presence of the surface-modified MWCNTs. The metabolic activities of osteoblastic cells, cell proliferation properties, as well as cell morphology were studied. The surface modification of MWCNTs with biomimetic apatite exhibited a significant increase in the cell viability of osteoblasts, up to 67.23%. In the proliferation phases, there were many more cells in the biomimetic apatite-modified MWCNT samples than in the MWCNTs–COOH. There were no obvious changes in cell morphology in osteoblastic MG-63 cells cultured in the presence of these chemically-modified MWCNTs. The surface modification of MWCNTs with apatite achieves an effective enhancement of their biocompatibility.

  15. Pheochromocytoma (PC12 Cell Response on Mechanobactericidal Titanium Surfaces

    Directory of Open Access Journals (Sweden)

    Jason V. Wandiyanto

    2018-04-01

    Full Text Available Titanium is a biocompatible material that is frequently used for making implantable medical devices. Nanoengineering of the surface is the common method for increasing material biocompatibility, and while the nanostructured materials are well-known to represent attractive substrata for eukaryotic cells, very little information has been documented about the interaction between mammalian cells and bactericidal nanostructured surfaces. In this study, we investigated the effect of bactericidal titanium nanostructures on PC12 cell attachment and differentiation—a cell line which has become a widely used in vitro model to study neuronal differentiation. The effects of the nanostructures on the cells were then compared to effects observed when the cells were placed in contact with non-structured titanium. It was found that bactericidal nanostructured surfaces enhanced the attachment of neuron-like cells. In addition, the PC12 cells were able to differentiate on nanostructured surfaces, while the cells on non-structured surfaces were not able to do so. These promising results demonstrate the potential application of bactericidal nanostructured surfaces in biomedical applications such as cochlear and neuronal implants.

  16. Efficient numerical methods for simulating surface tension of multi-component mixtures with the gradient theory of fluid interfaces

    KAUST Repository

    Kou, Jisheng

    2015-08-01

    Surface tension significantly impacts subsurface flow and transport, and it is the main cause of capillary effect, a major immiscible two-phase flow mechanism for systems with a strong wettability preference. In this paper, we consider the numerical simulation of the surface tension of multi-component mixtures with the gradient theory of fluid interfaces. Major numerical challenges include that the system of the Euler-Lagrange equations is solved on the infinite interval and the coefficient matrix is not positive definite. We construct a linear transformation to reduce the Euler-Lagrange equations, and naturally introduce a path function, which is proven to be a monotonic function of the spatial coordinate variable. By using the linear transformation and the path function, we overcome the above difficulties and develop the efficient methods for calculating the interface and its interior compositions. Moreover, the computation of the surface tension is also simplified. The proposed methods do not need to solve the differential equation system, and they are easy to be implemented in practical applications. Numerical examples are tested to verify the efficiency of the proposed methods. © 2014 Elsevier B.V.

  17. Different responses of soil respiration and its components to nitrogen addition among biomes: a meta-analysis.

    Science.gov (United States)

    Zhou, Lingyan; Zhou, Xuhui; Zhang, Baocheng; Lu, Meng; Luo, Yiqi; Liu, Lingli; Li, Bo

    2014-07-01

    Anthropogenic activities have increased nitrogen (N) deposition by threefold to fivefold over the last century, which may considerably affect soil respiration (Rs). Although numerous individual studies and a few meta-analyses have been conducted, it remains controversial as to how N addition affects Rs and its components [i.e., autotrophic (Ra) and heterotrophic respiration (Rh)]. To reconcile the difference, we conducted a comprehensive meta-analysis of 295 published studies to examine the responses of Rs and its components to N addition in terrestrial ecosystems. We also assessed variations in their responses in relation to ecosystem types, environmental conditions, and experimental duration (DUR). Our results show that N addition significantly increased Rs by 2.0% across all biomes but decreased by 1.44% in forests and increased by 7.84% and 12.4% in grasslands and croplands, respectively (P biomes with more stimulation of Ra in croplands and grasslands compared with no significant change in forests. Rh exhibited a similar negative response to N addition among biomes except that in croplands, tropical and boreal forests. Methods of partitioning Rs did not induce significant differences in the responses of Ra or Rh to N addition, except that Ra from root exclusion and component integration methods exhibited the opposite responses in temperate forests. The response ratios (RR) of Rs to N addition were positively correlated with mean annual temperature (MAT), with being more significant when MAT was less than 15 °C, but negatively with DUR. In addition, the responses of Rs and its components to N addition largely resulted from the changes in root and microbial biomass and soil C content as indicated by correlation analysis. The response patterns of Rs to N addition as revealed in this study can be benchmarks for future modeling and experimental studies. © 2013 John Wiley & Sons Ltd.

  18. Global transcription profiling reveals differential responses to chronic nitrogen stress and putative nitrogen regulatory components in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Zhu Tong

    2007-08-01

    Full Text Available Abstract Background A large quantity of nitrogen (N fertilizer is used for crop production to achieve high yields at a significant economic and environmental cost. Efforts have been directed to understanding the molecular basis of plant responses to N and identifying N-responsive genes in order to manipulate their expression, thus enabling plants to use N more efficiently. No studies have yet delineated these responses at the transcriptional level when plants are grown under chronic N stress and the understanding of regulatory elements involved in N response is very limited. Results To further our understanding of the response of plants to varying N levels, a growth system was developed where N was the growth-limiting factor. An Arabidopsis whole genome microarray was used to evaluate global gene expression under different N conditions. Differentially expressed genes under mild or severe chronic N stress were identified. Mild N stress triggered only a small set of genes significantly different at the transcriptional level, which are largely involved in various stress responses. Plant responses were much more pronounced under severe N stress, involving a large number of genes in many different biological processes. Differentially expressed genes were also identified in response to short- and long-term N availability increases. Putative N regulatory elements were determined along with several previously known motifs involved in the responses to N and carbon availability as well as plant stress. Conclusion Differentially expressed genes identified provide additional insights into the coordination of the complex N responses of plants and the components of the N response mechanism. Putative N regulatory elements were identified to reveal possible new components of the regulatory network for plant N responses. A better understanding of the complex regulatory network for plant N responses will help lead to strategies to improve N use efficiency.

  19. Multivariate analysis of attachment of biofouling organisms in response to material surface characteristics.

    Science.gov (United States)

    Gatley-Montross, Caitlyn M; Finlay, John A; Aldred, Nick; Cassady, Harrison; Destino, Joel F; Orihuela, Beatriz; Hickner, Michael A; Clare, Anthony S; Rittschof, Daniel; Holm, Eric R; Detty, Michael R

    2017-12-29

    Multivariate analyses were used to investigate the influence of selected surface properties (Owens-Wendt surface energy and its dispersive and polar components, static water contact angle, conceptual sign of the surface charge, zeta potentials) on the attachment patterns of five biofouling organisms (Amphibalanus amphitrite, Amphibalanus improvisus, Bugula neritina, Ulva linza, and Navicula incerta) to better understand what surface properties drive attachment across multiple fouling organisms. A library of ten xerogel coatings and a glass standard provided a range of values for the selected surface properties to compare to biofouling attachment patterns. Results from the surface characterization and biological assays were analyzed separately and in combination using multivariate statistical methods. Principal coordinate analysis of the surface property characterization and the biological assays resulted in different groupings of the xerogel coatings. In particular, the biofouling organisms were able to distinguish four coatings that were not distinguishable by the surface properties of this study. The authors used canonical analysis of principal coordinates (CAP) to identify surface properties governing attachment across all five biofouling species. The CAP pointed to surface energy and surface charge as important drivers of patterns in biological attachment, but also suggested that differentiation of the surfaces was influenced to a comparable or greater extent by the dispersive component of surface energy.

  20. Application of response surface methodology for determining cutting ...

    Indian Academy of Sciences (India)

    Cutting force is classified among the most important technological parameter to control in machining process. It is the background for the evaluation of the necessary power machining. (choice of the electric motor). It is also used for dimensioning of machine tool components and the tool body. It influences machining system ...

  1. Application of response surface methodology to the optimization of ...

    African Journals Online (AJOL)

    This research paper mainly focused on developing a media by optimizing parameters like sweet potato concentration, sodium nitrate concentration, pH, temperature for the maximum production of amylase by Aspergillus oryzae MTCC 1847. Optimization of the medium components such as sweet potato (carbon source), ...

  2. 2004 Workplace and Gender Relations Survey of Reserve Component Members: Tabulations of Responses

    National Research Council Canada - National Science Library

    2005-01-01

    The 2004 Workplace and Gender Relations Survey of Reserve Component Members was designed to both estimate the level of sexual harassment and provide information on a variety of consequences of sexual harassment...

  3. Facile Synthesis of Smart Nanocontainers as Key Components for Construction of Self-Healing Coating with Superhydrophobic Surfaces.

    Science.gov (United States)

    Liang, Yi; Wang, MingDong; Wang, Cheng; Feng, Jing; Li, JianSheng; Wang, LianJun; Fu, JiaJun

    2016-12-01

    SiO2-imidazoline nanocomposites (SiO2-IMI) owning high loading capacity of corrosion inhibitor, 1-hexadecyl-3-methylimidazolium bromide (HMID), and a special acid/alkali dual-stimuli-accelerated release property have been synthesized via a one-step modified Stöber method. SiO2-IMI were uniformly distributed into the hydrophobic SiO2 sol to construct "host"-"guest" feedback active coating with a superhydrophobic surface (SiO2-IMI@SHSC) on aluminium alloy, AA2024, by dip-coating technique. SiO2-IMI as "guest" components have good compatibility with "host" sol-gel coating, and more importantly, once localized corrosion occurs on the surface of AA2024, SiO2-IMI can simultaneously respond to the increase in environmental pH around corrosive micro-cathodic regions and decrease in pH near micro-anodic regions, promptly releasing HMID to form a compact molecular film on the damaged surface, inhibiting corrosion spread and executing a self-healing function. The scanning vibrating electrode technique (SVET) was applied to illustrate the suppression process of cathodic/anodic corrosion activities. Furthermore, benefiting from the superhydrophobic surface, SiO2-IMI@SHSC remained its protective ability after immersion in 0.5 M NaCl solution for 35 days, which is far superior to the conventional sol-gel coating with the same coating thickness. The facile fabrication method of SiO2-IMI simplifies the construction procedure of SiO2-IMI@SHSC, which have great potential to replace non-environmental chromate conversion coatings for practical use.

  4. Facile Synthesis of Smart Nanocontainers as Key Components for Construction of Self-Healing Coating with Superhydrophobic Surfaces

    Science.gov (United States)

    Liang, Yi; Wang, MingDong; Wang, Cheng; Feng, Jing; Li, JianSheng; Wang, LianJun; Fu, JiaJun

    2016-04-01

    SiO2-imidazoline nanocomposites (SiO2-IMI) owning high loading capacity of corrosion inhibitor, 1-hexadecyl-3-methylimidazolium bromide (HMID), and a special acid/alkali dual-stimuli-accelerated release property have been synthesized via a one-step modified Stöber method. SiO2-IMI were uniformly distributed into the hydrophobic SiO2 sol to construct "host"-"guest" feedback active coating with a superhydrophobic surface (SiO2-IMI@SHSC) on aluminium alloy, AA2024, by dip-coating technique. SiO2-IMI as "guest" components have good compatibility with "host" sol-gel coating, and more importantly, once localized corrosion occurs on the surface of AA2024, SiO2-IMI can simultaneously respond to the increase in environmental pH around corrosive micro-cathodic regions and decrease in pH near micro-anodic regions, promptly releasing HMID to form a compact molecular film on the damaged surface, inhibiting corrosion spread and executing a self-healing function. The scanning vibrating electrode technique (SVET) was applied to illustrate the suppression process of cathodic/anodic corrosion activities. Furthermore, benefiting from the superhydrophobic surface, SiO2-IMI@SHSC remained its protective ability after immersion in 0.5 M NaCl solution for 35 days, which is far superior to the conventional sol-gel coating with the same coating thickness. The facile fabrication method of SiO2-IMI simplifies the construction procedure of SiO2-IMI@SHSC, which have great potential to replace non-environmental chromate conversion coatings for practical use.

  5. Enzyme-enabled responsive surfaces for anti-contamination materials.

    Science.gov (United States)

    Wu, Songtao; Buthe, Andreas; Jia, Hongfei; Zhang, Minjuan; Ishii, Masahiko; Wang, Ping

    2013-06-01

    Many real-life stains have origins from biological matters including proteins, lipids, and carbohydrates that act as gluing agents binding along with other particulates or microbes to exposed surfaces of automobiles, furniture, and fabrics. Mimicking naturally occurring self-defensive processes, we demonstrate in this work that a solid surface carrying partially exposed enzyme granules protected the surface in situ from contamination by biological stains and fingerprints. Attributed to the activities of enzymes which can be made compatible with a wide range of materials, such anti-contamination and self-cleaning functionalities are highly selective and efficient toward sticky chemicals. This observation promises a new mechanism in developing smart materials with desired anti-microbial, self-reporting, self-cleaning, or self-healing functions. Copyright © 2013 Wiley Periodicals, Inc.

  6. Water quality responses to the interaction between surface water and groundwater along the Songhua River, NE China

    Science.gov (United States)

    Teng, Yanguo; Hu, Bin; Zheng, Jieqiong; Wang, Jinsheng; Zhai, Yuanzheng; Zhu, Chen

    2018-03-01

    Investigation of surface water and groundwater interaction (SW-GW interaction) provides basic information for regional water-resource protection, management, and development. In this survey of a 10-km-wide area along both sides of the Songhua River, northeast China, the hydrogeochemical responses to different SW-GW interactions were studied. Three types of SW-GW interactions were identified—"recharge", "discharge", and "flow-through"—according to the hydraulic connection between the surface water and groundwater. The single factor index, principal component analysis, and hierarchical cluster analysis of the hydrogeochemistry and pollutant data illuminated the hydrogeochemical response to the various SW-GW interactions. Clear SW-GW interactions along the Songhua River were revealed: (1) upstream in the study area, groundwater usually discharges into the surface water, (2) groundwater is recharged by surface water downstream, and (3) discharge and flow-through coexist in between. Statistical analysis indicated that the degree of hydrogeochemical response in different types of hydraulic connection varied, being clear in recharge and flow-through modes, and less obvious in discharge mode. During the interaction process, dilution, adsorption, redox reactions, nitrification, denitrification, and biodegradation contributed to the pollutant concentration and affected hydrogeochemical response in the hyporheic zone.

  7. Response of the global surface ozone distribution to Northern Hemisphere sea surface temperature changes: implications for long-range transport

    Science.gov (United States)

    Yi, Kan; Liu, Junfeng; Ban-Weiss, George; Zhang, Jiachen; Tao, Wei; Cheng, Yanli; Tao, Shu

    2017-07-01

    The response of surface ozone (O3) concentrations to basin-scale warming and cooling of Northern Hemisphere oceans is investigated using the Community Earth System Model (CESM). Idealized, spatially uniform sea surface temperature (SST) anomalies of ±1 °C are individually superimposed onto the North Pacific, North Atlantic, and North Indian oceans. Our simulations suggest large seasonal and regional variability in surface O3 in response to SST anomalies, especially in the boreal summer. The responses of surface O3 associated with basin-scale SST warming and cooling have similar magnitude but are opposite in sign. Increasing the SST by 1 °C in one of the oceans generally decreases the surface O3 concentrations from 1 to 5 ppbv. With fixed emissions, SST increases in a specific ocean basin in the Northern Hemisphere tend to increase the summertime surface O3 concentrations over upwind regions, accompanied by a widespread reduction over downwind continents. We implement the integrated process rate (IPR) analysis in CESM and find that meteorological O3 transport in response to SST changes is the key process causing surface O3 perturbations in most cases. During the boreal summer, basin-scale SST warming facilitates the vertical transport of O3 to the surface over upwind regions while significantly reducing the vertical transport over downwind continents. This process, as confirmed by tagged CO-like tracers, indicates a considerable suppression of intercontinental O3 transport due to increased tropospheric stability at lower midlatitudes induced by SST changes. Conversely, the responses of chemical O3 production to regional SST warming can exert positive effects on surface O3 levels over highly polluted continents, except South Asia, where intensified cloud loading in response to North Indian SST warming depresses both the surface air temperature and solar radiation, and thus photochemical O3 production. Our findings indicate a robust linkage between basin-scale SST

  8. Response of the global surface ozone distribution to Northern Hemisphere sea surface temperature changes: implications for long-range transport

    Directory of Open Access Journals (Sweden)

    K. Yi

    2017-07-01

    Full Text Available The response of surface ozone (O3 concentrations to basin-scale warming and cooling of Northern Hemisphere oceans is investigated using the Community Earth System Model (CESM. Idealized, spatially uniform sea surface temperature (SST anomalies of ±1 °C are individually superimposed onto the North Pacific, North Atlantic, and North Indian oceans. Our simulations suggest large seasonal and regional variability in surface O3 in response to SST anomalies, especially in the boreal summer. The responses of surface O3 associated with basin-scale SST warming and cooling have similar magnitude but are opposite in sign. Increasing the SST by 1 °C in one of the oceans generally decreases the surface O3 concentrations from 1 to 5 ppbv. With fixed emissions, SST increases in a specific ocean basin in the Northern Hemisphere tend to increase the summertime surface O3 concentrations over upwind regions, accompanied by a widespread reduction over downwind continents. We implement the integrated process rate (IPR analysis in CESM and find that meteorological O3 transport in response to SST changes is the key process causing surface O3 perturbations in most cases. During the boreal summer, basin-scale SST warming facilitates the vertical transport of O3 to the surface over upwind regions while significantly reducing the vertical transport over downwind continents. This process, as confirmed by tagged CO-like tracers, indicates a considerable suppression of intercontinental O3 transport due to increased tropospheric stability at lower midlatitudes induced by SST changes. Conversely, the responses of chemical O3 production to regional SST warming can exert positive effects on surface O3 levels over highly polluted continents, except South Asia, where intensified cloud loading in response to North Indian SST warming depresses both the surface air temperature and solar radiation, and thus photochemical O3 production. Our findings indicate a robust linkage

  9. The Influence of implant geometry and surface composition on bone response

    NARCIS (Netherlands)

    Al Farraj Aldosari, A.; Anil, S.; Alasqah, M.; Wazzan, K.A. Al; Jetaily, S.A. Al; Jansen, J.A.

    2014-01-01

    OBJECTIVES: The implant design and surface modification are independent conditions that can alter the implant bone response. The objective of this study is to compare the bone response to roughened tapered and cylindrical screw-type implants with and without hydroxyapatite (HA) surface coating in

  10. X-37 C-Sic CMC Control Surface Components Development [Status of the NASA/Boeing/USAF Orbital Vehicle and Related Efforts

    Science.gov (United States)

    Valentine, Peter G; Rivers, H. Kevin; Chen, Victor L.

    2004-01-01

    Carbon/Silicon-Carbide (C-Sic) ceramic matrix composite (CMC) flaperon and ruddervator control surface components are being developed for the X-37 Orbital Vehicle (OV). The results of the prior NASA LaRC led work, aimed at developing C-Sic flaperon and ruddervator components for the X-37, will be reviewed. The status of several on-going and/or planned NASA, USAF, and Boeing programs that will support the development of control surface components for the X-37 OV will also be reviewed. The overall design and development philosophy being employed to assemble a team(s) to develop both: (a) C-Sic hot structure control surface components for the X-37 OV, and (b) carbon-carbon (C-C) hot structure components (a risk-reduction backup option for the OV), will be presented.

  11. Auditory evoked responses to binaural beat illusion: stimulus generation and the derivation of the Binaural Interaction Component (BIC).

    Science.gov (United States)

    Ozdamar, Ozcan; Bohorquez, Jorge; Mihajloski, Todor; Yavuz, Erdem; Lachowska, Magdalena

    2011-01-01

    Electrophysiological indices of auditory binaural beats illusions are studied using late latency evoked responses. Binaural beats are generated by continuous monaural FM tones with slightly different ascending and descending frequencies lasting about 25 ms presented at 1 sec intervals. Frequency changes are carefully adjusted to avoid any creation of abrupt waveform changes. Binaural Interaction Component (BIC) analysis is used to separate the neural responses due to binaural involvement. The results show that the transient auditory evoked responses can be obtained from the auditory illusion of binaural beats.

  12. Protective structures on the surface of zirconium components of light water reactor cores: Formation, testing, and prototype equipment

    Energy Technology Data Exchange (ETDEWEB)

    Begrambekov, L. B.; Gordeev, A. A.; Evsin, A. E., E-mail: evsin@plasma.mephi.ru; Ivanova, S. V.; Kaplevsky, A. S.; Sadovskiy, Ya. A. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation)

    2015-12-15

    The results of tests of plasma treatment of zirconium and deposition of protective yttrium coatings used as the methods of protection of zirconium components of light water reactor cores against hydrogenation are detailed. The amount of hydrogen in the treated sample exposed to superheated steam for 2500 h at temperature T = 400°C and pressure p = 1 atm was five times lower than the corresponding value for the untreated one. The amount of hydrogen in the sample coated with yttrium remained almost unchanged in 4000 h of exposure. A plasma method for rapid testing for hydrogen resistance is proposed. The hydrogenation rate provided by this method is 700 times higher than that in tests with superheated steam. The results of preliminary experiments confirm the possibility of constructing a unit for batch processing of the surfaces of fuel rod claddings.

  13. Protective structures on the surface of zirconium components of light water reactor cores: Formation, testing, and prototype equipment

    Science.gov (United States)

    Begrambekov, L. B.; Gordeev, A. A.; Evsin, A. E.; Ivanova, S. V.; Kaplevsky, A. S.; Sadovskiy, Ya. A.

    2015-12-01

    The results of tests of plasma treatment of zirconium and deposition of protective yttrium coatings used as the methods of protection of zirconium components of light water reactor cores against hydrogenation are detailed. The amount of hydrogen in the treated sample exposed to superheated steam for 2500 h at temperature T = 400°C and pressure p = 1 atm was five times lower than the corresponding value for the untreated one. The amount of hydrogen in the sample coated with yttrium remained almost unchanged in 4000 h of exposure. A plasma method for rapid testing for hydrogen resistance is proposed. The hydrogenation rate provided by this method is 700 times higher than that in tests with superheated steam. The results of preliminary experiments confirm the possibility of constructing a unit for batch processing of the surfaces of fuel rod claddings.

  14. Theoretical insight of physical adsorption for a single-component adsorbent+adsorbate system: I. Thermodynamic property surfaces.

    Science.gov (United States)

    Chakraborty, Anutosh; Saha, Bidyut Baran; Ng, Kim Choon; Koyama, Shigeru; Srinivasan, Kandadai

    2009-02-17

    Thermodynamic property surfaces for a single-component adsorbent+adsorbate system are derived and developed from the viewpoint of classical thermodynamics, thermodynamic requirements of chemical equilibrium, Gibbs law, and Maxwell relations. They enable us to compute the entropy and enthalpy of the adsorbed phase, the isosteric heat of adsorption, specific heat capacity, and the adsorbed phase volume thoroughly. These equations are very simple and easy to handle for calculating the energetic performances of any adsorption system. We have shown here that the derived thermodynamic formulations fill up the information gap with respect to the state of adsorbed phase to dispel the confusion as to what is the actual state of the adsorbed phase. We have also discussed and established the temperature-entropy diagrams of (i) CaCl2-in-silica gel+water system for cooling applications, and (ii) activated carbon (Maxsorb III)+methane system for gas storage.

  15. A countermeasure for external stress corrosion cracking in piping components by means of residual stress improvement on the outer surface

    International Nuclear Information System (INIS)

    Tanaka, Yasuhiro; Umemoto, Tadahiro

    1988-01-01

    Many techniques have been proposed as countermeasures for the External Stress Corrosion Cracking (ESCC) on austenitic stainless steel piping caused by sea salt particles. However, not one seems perfect. The method proposed here is an expansion of IHSI (Induction Heating Stress Improvement) which has been successfully implemented in many nuclear power plants as a remedy for Intergranular Stress Corrossion Cracking. The proposed method named EIHSI (External IHSI) can make the residual stress compressive on the outer surface of the piping components. In order to confirm the effectiveness of EIHSI, one series of tests were conducted on a weld joint between the pipe flange and the straight pipe. The measured residual stresses and also the results of the cracking test revealed that EIHSI is a superior method to suppress the ESCC. The outline of EIHSI and the verification tests are presented in this paper. (author)

  16. Theoretical Insight of Physical Adsorption for a Single-Component Adsorbent + Adsorbate System: I. Thermodynamic Property Surfaces

    KAUST Repository

    Chakraborty, Anutosh

    2009-02-17

    Thermodynamic property surfaces for a single-component adsorbent + adsorbate system are derived and developed from the viewpoint of classical thermodynamics, thermodynamic requirements of chemical equilibrium, Gibbs law, and Maxwell relations. They enable us to compute the entropy and enthalpy of the adsorbed phase, the isosteric heat of adsorption, specific heat capacity, and the adsorbed phase volume thoroughly. These equations are very simple and easy to handle for calculating the energetic performances of any adsorption system. We have shown here that the derived thermodynamic formulations fill up the information gap with respect to the state of adsorbed phase to dispel the confusion as to what is the actual state of the adsorbed phase. We have also discussed and established the temperature-entropy diagrams of (i) CaCl 2-in-silica gel + water system for cooling applications, and (ii) activated carbon (Maxsorb III) + methane system for gas storage. © Copyright 2009 American Chemical Society.

  17. Response surface optimization of biosurfactant produced by Pseudomonas aeruginosa MA01 isolated from spoiled apples.

    Science.gov (United States)

    Abbasi, Habib; Sharafi, Hakimeh; Alidost, Leila; Bodagh, Atefe; Zahiri, Hossein Shahbani; Noghabi, Kambiz Akbari

    2013-01-01

    A potent biosurfactant-producing bacterial strain isolated from spoiled apples was identified by 16S rRNA as Pseudomonas aeruginosa MA01. Compositional analysis revealed that the extracted biosurfactant was composed of high percentages of lipid (66%, w/w) and carbohydrate (32%, w/w). The surface tension of pure water decreased gradually with increasing biosurfactant concentration to 32.5 mN m(-1) with critical micelle concentration (CMC) value of 10.1 mg L(-1). The Fourier transform infrared spectrum of extracted biosurfactant confirmed the glycolipid nature of this natural product. Response surface methodology (RSM) was employed to optimize the biosynthesis medium for the production of MA01 biosurfactant. Nineteen carbon sources and 11 nitrogen sources were examined, with soybean oil and sodium nitrate being the most effective carbon and nitrogen sources on biosurfactant production, respectively. Among the organic nitrogen sources examined, yeast extract was necessary as a complementary nitrogen source for high production yield. Biosurfactant production at the optimum value of fermentation processing factor (15.68 g/L) was 29.5% higher than the biosurfactant concentration obtained before the RSM optimization (12.1 g/L). A central composite design algorithm was used to optimize the levels of key medium components, and it was concluded that two stages of optimization using RSM could increase biosurfactant production by 1.46 times, as compared to the values obtained before optimization.

  18. Antiproliferative activity of Curcuma phaeocaulis Valeton extract using ultrasonic assistance and response surface methodology.

    Science.gov (United States)

    Wang, Xiaoqin; Jiang, Ying; Hu, Daode

    2017-01-02

    The objective of the study was to optimize the ultrasonic-assisted extraction of curdione, furanodienone, curcumol, and germacrone from Curcuma phaeocaulis Valeton (Val.) and investigate the antiproliferative activity of the extract. Under the suitable high-performance liquid chromatography condition, the calibration curves for these four tested compounds showed high levels of linearity and the recoveries of these four compounds were between 97.9 and 104.3%. Response surface methodology (RSM) combining central composite design and desirability function (DF) was used to define optimal extraction parameters. The results of RSM and DF revealed that the optimum conditions were obtained as 8 mL g -1 for liquid-solid ratio, 70% ethanol concentration, and 20 min of ultrasonic time. It was found that the surface structures of the sonicated herbal materials were fluffy and irregular. The C. phaeocaulis Val. extract significantly inhibited the proliferation of RKO and HT-29 cells in vitro. The results reveal that the RSM can be effectively used for optimizing the ultrasonic-assisted extraction of bioactive components from C. phaeocaulis Val. for antiproliferative activity.

  19. Reliability Study of Solder Paste Alloy for the Improvement of Solder Joint at Surface Mount Fine-Pitch Components

    Directory of Open Access Journals (Sweden)

    Mohd Nizam Ab. Rahman

    2014-12-01

    Full Text Available The significant increase in metal costs has forced the electronics industry to provide new materials and methods to reduce costs, while maintaining customers’ high-quality expectations. This paper considers the problem of most electronic industries in reducing costly materials, by introducing a solder paste with alloy composition tin 98.3%, silver 0.3%, and copper 0.7%, used for the construction of the surface mount fine-pitch component on a Printing Wiring Board (PWB. The reliability of the solder joint between electronic components and PWB is evaluated through the dynamic characteristic test, thermal shock test, and Taguchi method after the printing process. After experimenting with the dynamic characteristic test and thermal shock test with 20 boards, the solder paste was still able to provide a high-quality solder joint. In particular, the Taguchi method is used to determine the optimal control parameters and noise factors of the Solder Printer (SP machine, that affects solder volume and solder height. The control parameters include table separation distance, squeegee speed, squeegee pressure, and table speed of the SP machine. The result shows that the most significant parameter for the solder volume is squeegee pressure (2.0 mm, and the solder height is the table speed of the SP machine (2.5 mm/s.

  20. Proceedings of US/Japan workshop, Q219 on high heat flux components and plasma surface interactions for next fusion devices

    International Nuclear Information System (INIS)

    Ulrickson, M.A.; Stevens, P.L.; Hino, T.; Hirohata, Y.

    1996-12-01

    This report contains the viewgraphs from the proceedings of US/Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices. Some of the general topics covered by this report are: PFC/PSI in tokamak and helical devices; development of high heat flux components; PSIS and plasma facing materials;tritium; and material damage

  1. Proceedings of US/Japan workshop, Q219 on high heat flux components and plasma surface interactions for next fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Ulrickson, M.A.; Stevens, P.L.; Hino, T.; Hirohata, Y. [eds.

    1996-12-01

    This report contains the viewgraphs from the proceedings of US/Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices. Some of the general topics covered by this report are: PFC/PSI in tokamak and helical devices; development of high heat flux components; PSIS and plasma facing materials;tritium; and material damage.

  2. Localization of the event-related potential novelty response as defined by principal components analysis.

    Science.gov (United States)

    Dien, Joseph; Spencer, Kevin M; Donchin, Emanuel

    2003-10-01

    Recent research indicates that novel stimuli elicit at least two distinct components, the Novelty P3 and the P300. The P300 is thought to be elicited when a context updating mechanism is activated by a wide class of deviant events. The functional significance of the Novelty P3 is uncertain. Identification of the generator sources of the two components could provide additional information about their functional significance. Previous localization efforts have yielded conflicting results. The present report demonstrates that the use of principal components analysis (PCA) results in better convergence with knowledge about functional neuroanatomy than did previous localization efforts. The results are also more convincing than that obtained by two alternative methods, MUSIC-RAP and the Minimum Norm. Source modeling on 129-channel data with BESA and BrainVoyager suggests the P300 has sources in the temporal-parietal junction whereas the Novelty P3 has sources in the anterior cingulate.

  3. Hydrodynamic effects of eroded materials on response of plasma-facing component during a tokamak disruption

    International Nuclear Information System (INIS)

    Hassanein, A.; Konkashbaev, I.

    1999-01-01

    Loss of plasma confinement causes surface and structural damage to plasma-facing materials (PFMs) and remains a major obstacle for tokamak reactors. The deposited plasma energy results in surface erosion and structural failure. The surface erosion consists of vaporization, spallation, and liquid splatter of metallic materials, while the structural damage includes large temperature increases in structural materials and at the interfaces between surface coatings and structural members. Comprehensive models (contained in the HEIGHTS computer simulation package) are being used self-consistently to evaluate material damage. Splashing mechanisms occur as a result of volume bubble boiling and liquid hydrodynamic instabilities and brittle destruction mechanisms of nonmelting materials. The effect of macroscopic erosion on total mass losses and lifetime is evaluated. The macroscopic erosion products may further protect PFMs from severe erosion (via the droplet-shielding effect) in a manner similar to that of the vapor shielding concept

  4. Surface effects on the electroelastic responses of a thin piezoelectric plate with nanoscale thickness

    International Nuclear Information System (INIS)

    Yan Zhi; Jiang Liying

    2012-01-01

    This work aims to investigate the electroelastic responses of a thin piezoelectric plate under mechanical and electrical loads with the consideration of surface effects. Surface effects, including surface elasticity, residual surface stress and surface piezoelectricity, are incorporated into the conventional Kirchhoff plate theory for a piezoelectric plate via the surface piezoelectricity model and the generalized Young-Laplace equations. Different from the results predicted by the conventional plate theory ignoring the surface effects, the proposed model predicts size-dependent behaviours of the piezoelectric thin plate with nanoscale thickness. It is found that surface effects have significant influence on the electroelastic responses of the piezoelectric nanoplate. This work is expected to provide more accurate predictions on characterizing nanofilm or nanoribbon based piezoelectric devices in nanoelectromechanical systems. (paper)

  5. Direct transcriptional activation of BT genes by NLP transcription factors is a key component of the nitrate response in Arabidopsis.

    Science.gov (United States)

    Sato, Takeo; Maekawa, Shugo; Konishi, Mineko; Yoshioka, Nozomi; Sasaki, Yuki; Maeda, Haruna; Ishida, Tetsuya; Kato, Yuki; Yamaguchi, Junji; Yanagisawa, Shuichi

    2017-01-29

    Nitrate modulates growth and development, functioning as a nutrient signal in plants. Although many changes in physiological processes in response to nitrate have been well characterized as nitrate responses, the molecular mechanisms underlying the nitrate response are not yet fully understood. Here, we show that NLP transcription factors, which are key regulators of the nitrate response, directly activate the nitrate-inducible expression of BT1 and BT2 encoding putative scaffold proteins with a plant-specific domain structure in Arabidopsis. Interestingly, the 35S promoter-driven expression of BT2 partially rescued growth inhibition caused by reductions in NLP activity in Arabidopsis. Furthermore, simultaneous disruption of BT1 and BT2 affected nitrate-dependent lateral root development. These results suggest that direct activation of BT1 and BT2 by NLP transcriptional activators is a key component of the molecular mechanism underlying the nitrate response in Arabidopsis. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Quality assurance in ceramic materials and components. High-resolution non-destructive testing especially of ceramic surfaces

    International Nuclear Information System (INIS)

    Reiter, H.; Hoffmann, B.; Morsch, A.; Arnold, W.; Schneider, E.

    1988-01-01

    This report discusses the influence of defects on the failure behavior of ceramic materials under four-point bending stress. In this connection various Si 3 N 4 and SiC materials with and without artificially introduced defect particles (Fe, WC, Si, pores) were examined by the following non-destructive test methods: photoacoustic microscopy, scanning laser acoustic microscopy, microfocus roentgenoscopy and ultrasound transit-time measurements. Finally, a four-point bending test and a fracture-mechanical evaluation of the fracture-incuding defects were carried out at the Institute for reliability and failure studies in mechanical engineering of the University of Karlsruhe. According to the type of stress the samples predominantly failed in the case of defects in the surface zone of the side in tension. Among the ndt methods applied the photoacoustic microscopy as a typical surface testing method could predict most of the fracture-inducing defects (30-50 %) without causing destruction. In this connection a different detection sensitivity which corresponds to the thermal reflection factors became apparent according to the type of defect. Furthermore the reports describes the results of some preliminary tests on ndt of green ceramics. In these investigations both the microfocus roentgenoscopy test and the roentgen computed tomography showed a high potential of detecting inhomogeneities and defects in green Si 3 N 4 and SiC components. (orig.) [de

  7. Relevance of the two-component sensor protein CiaH to acid and oxidative stress responses in Streptococcus pyogenes.

    Science.gov (United States)

    Tatsuno, Ichiro; Isaka, Masanori; Okada, Ryo; Zhang, Yan; Hasegawa, Tadao

    2014-03-28

    The production of virulence proteins depends on environmental factors, and two-component regulatory systems are involved in sensing these factors. We previously established knockout strains in all suspected two-component regulatory sensor proteins of the emm1 clinical strain of S. pyogenes and examined their relevance to acid stimuli in a natural atmosphere. In the present study, their relevance to acid stimuli was re-examined in an atmosphere containing 5% CO2. The spy1236 (which is identical to ciaHpy) sensor knockout strain showed significant growth reduction compared with the parental strain in broth at pH 6.0, suggesting that the Spy1236 (CiaHpy) two-component sensor protein is involved in acid response of S. pyogenes. CiaH is also conserved in Streptococcus pneumoniae, and it has been reported that deletion of the gene for its cognate response regulator (ciaRpn) made the pneumococcal strains more sensitive to oxidative stress. In this report, we show that the spy1236 knockout mutant of S. pyogenes is more sensitive to oxidative stress than the parental strain. These results suggest that the two-component sensor protein CiaH is involved in stress responses in S. pyogenes.

  8. Response surface method optimization of ectoine fermentation medium with moderate halophilic bacteria Halomonas sp. H02

    Science.gov (United States)

    Li, T. T.; Qu, A.; Yuan, X. N.; Tan, F. X.; Li, X. W.; Wang, T.; Zhang, L. H.

    2017-07-01

    Moderate halophilic bacteria are of halophilic bacteria whose suitable growth of NaCl is 5-10%. When the moderate halophilic bacteria response to high osmotic stress, the intracellular will synthesize small organic molecule compatible solutes. Ectoine, which is the major synthetic osmotic compatible solutes for moderate halophilic bacteria, can help microbial enzymes, nucleic acids and the whole cell resist to hypertonic, high temperature, freezing and other inverse environment. In order to increase the Ectoine production of Moderate halophilic bacteria Halomonas sp. H02, the Ectoine fermentation medium component was optimized by Plackett-Burman (PB) and Response Surface Methodology (RSM) based on the principle of non-complete equilibrium The results of PB experiments showed that the three main influencing factors of Moderate halophilic bacteria Halomonas sp. H02 synthesis Ectoine culture medium were C5H8NNaO4 concentration, NaCl concentration and initial pH. According to the center point of the steepest climbing experiment, the central combination design experiment was used to show that the model is consistent with the actual situation. The optimum combination of three influencing factors were C5H8NNaO4 41 g/L, NaCl 87.2 g/L and initial pH 5.9, and the predicted amount of Ectoine was 1835.8 mg/L, increased by 41.6%.

  9. Osteoblast response to oxygen functionalised plasma polymer surfaces

    CERN Document Server

    Kelly, J M

    2001-01-01

    Thin organic films with oxygen-carbon functionalities were deposited from plasmas containing vapour of the small organic compounds: allyI alcohol, methyl vinyl ketone and acrylic acid with octadiene. Characterisation of the deposits was carried out using X-ray photoelectron spectroscopy, in conjunction with chemical derivatisation, and this showed that plasma polymers retained high levels of original monomer functionality when the plasmas were sustained at low power for a given monomer vapour flow rate. High levels of attachment of rat osteosarcoma (ROS 17/2.8) cells were observed on surfaces that had high concentrations of hydroxyl and carbonyl functionalities and intermediate concentrations of carboxyl functionality. Cells did not attach to the octadiene plasma polymer. Cell attachment to carboxyl and methyl functionalised self-assembled monolayers increased with increasing concentration of surface carboxyl groups. Adsorption of the extracellular matrix protein fibronectin to acrylic acid/octadiene plasma c...

  10. Investigation of the influence of FDM operating parameters on dynamic force response using IV-optimal design and principal component analysis

    Science.gov (United States)

    Mohamed, Omar Ahmed; Masood, Syed Hasan; Bhowmik, Jahar Lal

    2017-07-01

    To improve the functionality in regards to manufacturing products at low cost, several innovative additive manufacturing processes have been developed. Fused deposition modeling (FDM) is one the most prominent additive manufacturing processes for producing plastic products. Referring to the quality and functionality, there are many FDM process conditions contributing to the occurrence of poor quality and functionality of FDM manufactured products. Therefore, the effect of the build parameters on the functionality of FDM produced products need to be examined. In this study, an attempt has also been made to investigate the critical processing parameters affecting dynamic mechanical response of plastic part processed by FDM technology using IV-optimal response surface method coupled with principal component analysis technique. The results obtained from this study can be used in the future as a guide for future in selecting the appropriate process conditions before the manufacturing process of the product take place.

  11. Assessing regional crop water demand using a satellite-based combination equation with a land surface temperature component

    Science.gov (United States)

    Moyano, Maria Carmen; Garcia, Monica; Tornos, Lucia; Recuero, Laura; Palacios-Orueta, Alicia; Juana, Luis

    2015-04-01

    Quantification of daily evapotranspiration at regional levels is fundamental for improving agricultural and hydrological management, especially in water-scarce and climatic change vulnerable regions, like the Mediterranean basin. Regional estimates of daily crop evapotranspiration (ET) have been historically based on combination equations, such as Penman-Monteith or Priestley-Taylor, forced with weather-data inputs. However, the requirements for long term in-situ data, limit the application of such traditional approaches and algorithms using satellite-data without field calibrations bridge this gap by estimating long-term ET at the pixel level from local to global scales. Land surface temperature is a key variable tracking land surface moisture status. However, it has not been included in satellite ET approaches based on combination equations. In this study, a land surface temperature component was used to estimate soil surface conductance based on an apparent thermal inertia index. A process-based model was applied to estimate surface energy fluxes including daily ET based on a modified version of the Priestley-Taylor Jet Propulsion Laboratory (PT-JPL) model at 1km pixel resolution during a chrono-sequence spanning for more than a decade (2002-2013). The thermal-PT-JPL model was forced with vegetation, albedo, reflectance and temperature products from the Moderate-resolution Imaging Spectroradiometer (MODIS) from both Aqua and Terra satellites. The study region, B-XII Irrigation District of the Lower Guadalquivir, is one of the largest irrigated areas in Spain but it has scarce in-situ micrometeorological or eddy covariance data. The final aim of this study is to evaluate the thermal version of PT-JPL model versus a lumped hydrological model to assess crop evapotranspiration deficits and long-term water consumption trends in the area. The results showed that the thermal-PT-JPL model is a suitable and simple tool requiring only air temperature and incoming solar

  12. Plasma surface modification of chitosan membranes : characterization and preliminary cell response studies

    OpenAIRE

    Silva, Simone Santos; Luna, Sandra M.; Gomes, Manuela E.; Benesch, Johan; Pashkuleva, I.; Mano, J. F.; Reis, R. L.

    2008-01-01

    Surface modification of biomaterials is a way to tailor cell responses whilst retaining the bulk properties. In this work, chitosan membranes were prepared by solvent casting and treated with nitrogen or argon plasma at 20Wfor 10–40 min. AFM indicated an increase in the surface roughness as a result of the ongoing etching process. XPS and contact angle measurements showed different surface elemental compositions and higher surface free energy. The MTS test and direct contact...

  13. Detecting geothermal anomalies and evaluating LST geothermal component by combining thermal remote sensing time series and land surface model data

    Science.gov (United States)

    Romaguera, Mireia; Vaughan, R. Greg; Ettema, J.; Izquierdo-Verdiguier, E.; Hecker, C. A.; van der Meer, F.D.

    2018-01-01

    This paper explores for the first time the possibilities to use two land surface temperature (LST) time series of different origins (geostationary Meteosat Second Generation satellite data and Noah land surface modelling, LSM), to detect geothermal anomalies and extract the geothermal component of LST, the LSTgt. We hypothesize that in geothermal areas the LSM time series will underestimate the LST as compared to the remote sensing data, since the former does not account for the geothermal component in its model.In order to extract LSTgt, two approaches of different nature (physical based and data mining) were developed and tested in an area of about 560 × 560 km2 centered at the Kenyan Rift. Pre-dawn data in the study area during the first 45 days of 2012 were analyzed.The results show consistent spatial and temporal LSTgt patterns between the two approaches, and systematic differences of about 2 K. A geothermal area map from surface studies was used to assess LSTgt inside and outside the geothermal boundaries. Spatial means were found to be higher inside the geothermal limits, as well as the relative frequency of occurrence of high LSTgt. Results further show that areas with strong topography can result in anomalously high LSTgt values (false positives), which suggests the need for a slope and aspect correction in the inputs to achieve realistic results in those areas. The uncertainty analysis indicates that large uncertainties of the input parameters may limit detection of LSTgt anomalies. To validate the approaches, higher spatial resolution images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data over the Olkaria geothermal field were used. An established method to estimate radiant geothermal flux was applied providing values between 9 and 24 W/m2 in the geothermal area, which coincides with the LSTgt flux rates obtained with the proposed approaches.The proposed approaches are a first step in estimating LSTgt

  14. Triethylene glycol, an active component of Ashwagandha (Withania somnifera leaves, is responsible for sleep induction.

    Directory of Open Access Journals (Sweden)

    Mahesh K Kaushik

    Full Text Available Insomnia is the most common sleep complaint which occurs due to difficulty in falling asleep or maintaining it. Most of currently available drugs for insomnia develop dependency and/or adverse effects. Hence natural therapies could be an alternative choice of treatment for insomnia. The root or whole plant extract of Ashwagandha (Withania somnifera has been used to induce sleep in Indian system of traditional home medicine, Ayurveda. However, its active somnogenic components remain unidentified. We investigated the effect of various components of Ashwagandha leaf on sleep regulation by oral administration in mice. We found that the alcoholic extract that contained high amount of active withanolides was ineffective to induce sleep in mice. However, the water extract which contain triethylene glycol as a major component induced significant amount of non-rapid eye movement sleep with slight change in rapid eye movement sleep. Commercially available triethylene glycol also increased non-rapid eye movement sleep in mice in a dose-dependent (10-30 mg/mouse manner. These results clearly demonstrated that triethylene glycol is an active sleep-inducing component of Ashwagandha leaves and could potentially be useful for insomnia therapy.

  15. Logistic Regression Analysis of the Response of Winter Wheat to Components of Artificial Freezing Episodes

    Science.gov (United States)

    Improvement of cold tolerance of winter wheat (Triticum aestivum L.) through breeding methods has been problematic. A better understanding of how individual wheat cultivars respond to components of the freezing process may provide new information that can be used to develop more cold tolerance culti...

  16. Response Surface Optimized Extraction of Total Triterpene Acids ...

    African Journals Online (AJOL)

    Purpose: To optimize extraction of total triterpene acids from loquat leaf and evaluate their in vitro antioxidant activities. Methods: The independent variables were ethanol concentration, extraction time, and solvent ratio, while the dependent variable was content of total triterpene acids. Composite design and response.

  17. Component-Based Modelling for Scalable Smart City Systems Interoperability: A Case Study on Integrating Energy Demand Response Systems.

    Science.gov (United States)

    Palomar, Esther; Chen, Xiaohong; Liu, Zhiming; Maharjan, Sabita; Bowen, Jonathan

    2016-10-28

    Smart city systems embrace major challenges associated with climate change, energy efficiency, mobility and future services by embedding the virtual space into a complex cyber-physical system. Those systems are constantly evolving and scaling up, involving a wide range of integration among users, devices, utilities, public services and also policies. Modelling such complex dynamic systems' architectures has always been essential for the development and application of techniques/tools to support design and deployment of integration of new components, as well as for the analysis, verification, simulation and testing to ensure trustworthiness. This article reports on the definition and implementation of a scalable component-based architecture that supports a cooperative energy demand response (DR) system coordinating energy usage between neighbouring households. The proposed architecture, called refinement of Cyber-Physical Component Systems (rCPCS), which extends the refinement calculus for component and object system (rCOS) modelling method, is implemented using Eclipse Extensible Coordination Tools (ECT), i.e., Reo coordination language. With rCPCS implementation in Reo, we specify the communication, synchronisation and co-operation amongst the heterogeneous components of the system assuring, by design scalability and the interoperability, correctness of component cooperation.

  18. Response of sunflower (Helianthus annuus L.) leaf surface defenses to exogenous methyl jasmonate.

    Science.gov (United States)

    Rowe, Heather C; Ro, Dae-kyun; Rieseberg, Loren H

    2012-01-01

    Helianthus annuus, the common sunflower, produces a complex array of secondary compounds that are secreted into glandular trichomes, specialized structures found on leaf surfaces and anther appendages of flowers. The primary components of these trichome secretions are sesquiterpene lactones (STL), a diverse class of compounds produced abundantly by the plant family Compositae and believed to contribute to plant defense against herbivory. We treated wild and cultivated H. annuus accessions with exogenous methyl jasmonate, a plant hormone that mediates plant defense against insect herbivores and certain classes of fungal pathogens. The wild sunflower produced a higher density of glandular trichomes on its leaves than the cultivar. Comparison of the profiles of glandular trichome extracts obtained by liquid chromatography-mass spectroscopy (LC-MS) showed that wild and cultivated H. annuus were qualitatively similar in surface chemistry, although differing in the relative size and proportion of various compounds detected. Despite observing consistent transcriptional responses to methyl jasmonate treatment, we detected no significant effect on glandular trichome density or LC-MS profile in cultivated or wild sunflower, with wild sunflower exhibiting a declining trend in overall STL production and foliar glandular trichome density of jasmonate-treated plants. These results suggest that glandular trichomes and associated compounds may act as constitutive defenses or require greater levels of stimulus for induction than the observed transcriptional responses to exogenous jasmonate. Reduced defense investment in domesticated lines is consistent with predicted tradeoffs caused by selection for increased yield; future research will focus on the development of genetic resources to explicitly test the ecological roles of glandular trichomes and associated effects on plant growth and fitness.

  19. A Response Surface-Based Cost Model for Wind Farm Design

    International Nuclear Information System (INIS)

    Zhang Jie; Chowdhury, Souma; Messac, Achille; Castillo, Luciano

    2012-01-01

    A Response Surface-Based Wind Farm Cost (RS-WFC) model is developed for the engineering planning of wind farms. The RS-WFC model is developed using Extended Radial Basis Functions (E-RBF) for onshore wind farms in the U.S. This model is then used to explore the influences of different design and economic parameters, including number of turbines, rotor diameter and labor cost, on the cost of a wind farm. The RS-WFC model is composed of three components that estimate the effects of engineering and economic factors on (i) the installation cost, (ii) the annual Operation and Maintenance (O and M) cost, and (iii) the total annual cost of a wind farm. The accuracy of the cost model is favorably established through comparison with pertinent commercial data. The final RS-WFC model provided interesting insights into cost variation with respect to critical engineering and economic parameters. In addition, a newly developed analytical wind farm engineering model is used to determine the power generated by the farm, and the subsequent Cost of Energy (COE). This COE is optimized for a unidirectional uniform “incoming wind speed” scenario using Particle Swarm Optimization (PSO). We found that the COE could be appreciably minimized through layout optimization, thereby yielding significant cost savings. - Highlights: ► We present a Response Surface-Based Wind Farm Cost (RS-WFC) model for wind farm design. ► The model could estimate installation cost, Operation and Maintenance cost, and total annual cost of a wind farm. ► The Cost of Energy is optimized using Particle Swarm Optimization. ► Layout optimization could yield significant cost savings.

  20. Other components

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This chapter includes descriptions of electronic and mechanical components which do not merit a chapter to themselves. Other hardware requires mention because of particularly high tolerance or intolerance of exposure to radiation. A more systematic analysis of radiation responses of structures which are definable by material was given in section 3.8. The components discussed here are field effect transistors, transducers, temperature sensors, magnetic components, superconductors, mechanical sensors, and miscellaneous electronic components

  1. On Possible Similarity Solutions for Three-Dimensional Incompressible Laminar Boundary-Layer Flows Over Developable Surfaces and with Proportional Mainstream Velocity Components

    Science.gov (United States)

    Hansen, Arthur G.

    1958-01-01

    Analysis is presented on the possible similarity solutions of the three-dimensional, laminar, incompressible, boundary-layer equations referred to orthogonal, curvilinear coordinate systems. Requirements of the existence of similarity solutions are obtained for the following: flow over developable surface and flow over non-developable surfaces with proportional mainstream velocity components.

  2. Calculating the sensitivity of wind turbine loads to wind inputs using response surfaces

    DEFF Research Database (Denmark)

    Rinker, Jennifer M.

    2016-01-01

    at a low computational cost. Sobol sensitivity indices (SIs) can then be calculated with relative ease using the calibrated response surface. The proposed methodology is demonstrated by calculating the total sensitivity of the maximum blade root bending moment of the WindPACT 5 MW reference model to four......This paper presents a methodology to calculate wind turbine load sensitivities to turbulence parameters through the use of response surfaces. A response surface is a high-dimensional polynomial surface that can be calibrated to any set of input/output data and then used to generate synthetic data...... turbulence input parameters: a reference mean wind speed, a reference turbulence intensity, the Kaimal length scale, and a novel parameter reflecting the nonstationarity present in the inflow turbulence. The input/output data used to calibrate the response surface were generated for a previous project...

  3. Fetal alcohol exposure reduces responsiveness of taste nerves and trigeminal chemosensory neurons to ethanol and its flavor components.

    Science.gov (United States)

    Glendinning, John I; Tang, Joyce; Morales Allende, Ana Paula; Bryant, Bruce P; Youngentob, Lisa; Youngentob, Steven L

    2017-08-01

    chemosensory neurons. We found that FAE substantially reduced taste and trigeminal responsiveness to ethanol and its flavor components. Copyright © 2017 the American Physiological Society.

  4. Unravelling the genetic components involved in the immune response of pigs vaccinated against influenza virus.

    Science.gov (United States)

    Zanella, Ricardo; Gava, Danielle; Peixoto, Jane de Oliveira; Schaefer, Rejane; Ciacci-Zanella, Janice Reis; Biondo, Natalha; da Silva, Marcos Vinicius Gualberto Barbosa; Cantão, Maurício Egídio; Ledur, Mônica Corrêa

    2015-12-02

    A genome-wide association study for immune response to influenza vaccination in a crossbred swine population was conducted. Swine influenza is caused by influenza A virus (FLUAV) which is considered one of the most prevalent respiratory pathogens in swine worldwide. The main strategy used to control influenza in swine herds is through vaccination. However, the currently circulating FLUAV subtypes in swine are genetically and antigenically diverse and their interaction with the host genetics poses a challenge for the production of efficacious and cross-protective vaccines. In this study, 103 pigs vaccinated with an inactivated H1N1 pandemic virus were genotyped with the Illumina PorcineSNP60V2 BeadChip for the identification of genetic markers associated with immune response efficacy to influenza A virus vaccination. Immune response was measured based on the presence or absence of HA (hemagglutinin) and NP (nucleoprotein) antibodies induced by vaccination and detected in swine sera by the hemagglutination inhibition (HI) and ELISA assays, respectively. The ELISA test was also used as a measurement of antibody levels produced following the FLUAV vaccination. Associations were tested with x(2) test for a case and control data and using maximum likelihood method for the quantitative data, where a moderate association was considered if pimmune response. Using the response to vaccination measured by ELISA as a qualitative and quantitative phenotype, four genomic regions were associated with immune response: one on SSC12 and three on chromosomes SSC1, SSC7, and SSC15, respectively. Those regions harbor important functional candidate genes possibly involved with the degree of immune response to vaccination. These results show an important role of host genetics in the immune response to influenza vaccination. Genetic selection for pigs with better response to FLUAV vaccination might be an alternative to reduce the impact of influenza virus infection in the swine industry

  5. Surface mu heavy chain signals down-regulation of the V(D)J-recombinase machinery in the absence of surrogate light chain components.

    Science.gov (United States)

    Galler, Gunther R; Mundt, Cornelia; Parker, Mathew; Pelanda, Roberta; Mårtensson, Inga-Lill; Winkler, Thomas H

    2004-06-07

    Early B cell development is characterized by stepwise, ordered rearrangement of the immunoglobulin (Ig) heavy (HC) and light (LC) chain genes. Only one of the two alleles of these genes is used to produce a receptor, a phenomenon referred to as allelic exclusion. It has been suggested that pre-B cell receptor (pre-BCR) signals are responsible for down-regulation of the VDJH-recombinase machinery (Rag1, Rag2, and terminal deoxynucleotidyl transferase [TdT]), thereby preventing further rearrangement on the second HC allele. Using a mouse model, we show that expression of an inducible muHC transgene in Rag2-/- pro-B cells induces down-regulation of the following: (a) TdT protein, (b) a transgenic green fluorescent protein reporter reflecting endogenous Rag2 expression, and (c) Rag1 primary transcripts. Similar effects were also observed in the absence of surrogate LC (SLC) components, but not in the absence of the signaling subunit Ig-alpha. Furthermore, in wild-type mice and in mice lacking either lambda5, VpreB1/2, or the entire SLC, the TdT protein is down-regulated in muHC+LC- pre-B cells. Surprisingly, muHC without LC is expressed on the surface of pro-/pre-B cells from lambda5-/-, VpreB1-/-VpreB2-/-, and SLC-/- mice. Thus, SLC or LC is not required for muHC cell surface expression and signaling in these cells. Therefore, these findings offer an explanation for the occurrence of HC allelic exclusion in mice lacking SLC components.

  6. The acclimation of Tilia cordata stomatal opening in response to light, and stomatal anatomy to vegetational shade and its components.

    Science.gov (United States)

    Aasamaa, Krõõt; Aphalo, Pedro José

    2017-02-01

    Stomatal anatomical traits and rapid responses to several components of visible light were measured in Tilia cordata Mill. seedlings grown in an open, fully sunlit field (C-set), or under different kinds of shade. The main questions were: (i) stomatal responses to which visible light spectrum regions are modified by growth-environment shade and (ii) which separate component of vegetational shade is most effective in eliciting the acclimation effects of the full vegetational shade. We found that stomatal opening in response to red or green light did not differ between the plants grown in the different environments. Stomatal response to blue light was increased (in comparison with that of C-set) in the leaves grown in full vegetational shade (IABW-set), in attenuated UVAB irradiance (AB-set) or in decreased light intensity (neutral shade) plus attenuated UVAB irradiance (IAB-set). In all sets, the addition of green light-two or four times stronger-into induction light barely changed the rate of the blue-light-stimulated stomatal opening. In the AB-set, stomatal response to blue light equalled the strong IABW-set response. In attenuated UVB-grown leaves, stomatal response fell midway between IABW- and C-set results. Blue light response by neutral shade-grown leaves did not differ from that of the C-set, and the response by the IAB-set did not differ from that of the AB-set. Stomatal size was not modified by growth environments. Stomatal density and index were remarkably decreased only in the IABW- and IAB-sets. It was concluded that differences in white light responses between T. cordata leaves grown in different light environments are caused only by their different blue light response. Differences in stomatal sensitivity are not dependent on altered stomatal anatomy. Attenuated UVAB irradiance is the most efficient component of vegetational shade in stimulating acclimation of stomata, whereas decreased light intensity plays a minor role. © The Author 2016. Published

  7. Two components in IOR: evidence for response bias and perceptual processing delays using the SAT methodology.

    Science.gov (United States)

    Zhao, Yuanyuan; Heinke, Dietmar; Ivanoff, Jason; Klein, Raymond M; Humphreys, Glyn W

    2011-10-01

    Inhibition of return (IOR) occurs when reaction times (RTs) are slowed to respond to a target that appears at a previously attended location. We used the speed-accuracy trade-off (SAT) procedure to obtain conjoint measures of IOR on sensitivity and processing speed by presenting targets at cued and uncued locations. The results showed that IOR is associated with both delays in processing speed and shifts in response criterion. When the target was briefly presented, the results supported a criterion shift account of IOR. However, when the target was presented until response, the evidence indicated that, in addition to a response bias effect, there was an increase in the minimal time required for information about the target to accumulate above chance level. A hybrid account of IOR is suggested that describes effects on both response bias and perceptual processing.

  8. Differential allergy responses to Metarhizium anisopliae fungal component extracts in BALB/c mice

    Science.gov (United States)

    Intratracheal aspiration (IA) exposure to Metarhizium anisopliae crude antigen (MACA), which is composed of equal protein amounts of mycelium (MYC), conidia (CON) and inducible proteases/chitinases (IND) extracts/filtrates, has resulted in responses characteristic of human allerg...

  9. A critical assessment of direct radiative effects of different aerosol types on surface global radiation and its components

    International Nuclear Information System (INIS)

    Xia, Xiangao

    2014-01-01

    A critical assessment of direct radiative effects of different aerosol types on surface global, direct and diffuse radiation is presented. The analysis is based on measurements of aerosol optical properties and surface solar radiation (SSR) of cloud-free days at the Baseline Surface Radiation Network (BSRN) and Aerosol Robotic Network station (AERONET) of Xianghe over the North China Plain between October 2004 and May 2012. Six aerosol types are classified based on aerosol size and absorption from the AERONET retrieval products, including two coarse-mode dominated aerosol types: dust (DU: fine mode fraction (FMF)<0.4) and polluted dust (PD: FMF within 0.4–0.7) and four fine-mode dominated aerosol types (FMF>0.7) but with different single scattering albedo (SSA): highly absorbing (HA: SSA<0.85), moderately absorbing (MA: SSA within 0.85–0.90), slightly absorbing (SA: SSA within 0.90–0.95) and very weakly absorbing (WA: SSA>0.95). Dramatic differences in aerosol direct radiative effect (ADRE) on global SSR and its components between the six aerosol types have been revealed. ADRE efficiency on global SSR for solar zenight angle (SZA) between 55° and 65° ranges from −106 W m −2 for WA to −181 W m −2 for HA. The minimum ADRE efficiency on diffuse SSR is derived for HA aerosols, being 113 W m −2 that is about half of that by DU, the maximum value of six aerosol types. ADRE efficiency on global SSR by DU and PD (−141 to −150 W m −2 for SZA between 55° and 65°) is comparable to that by MA, although 100 W m −2 more direct SSR is extincted by DU and PD than by MA. DU and PD induce more diffuse SSR than MA that offsets larger reduction of direct SSR by DU and PD. Implications of the results to related researches are detailed discussed. The results are derived from aerosol and radiation data in the North China Plain, however the method can be used to any other stations with similar measurements. - Highlights: • A statistical method is developed to

  10. SASSYS-1 balance-of-plant component models for an integrated plant response

    International Nuclear Information System (INIS)

    Ku, J.-Y.

    1989-01-01

    Models of power plant heat transfer components and rotating machinery have been added to the balance-of-plant model in the SASSYS-1 liquid metal reactor systems analysis code. This work is part of a continuing effort in plant network simulation based on the general mathematical models developed. The models described in this paper extend the scope of the balance-of-plant model to handle non-adiabatic conditions along flow paths. While the mass and momentum equations remain the same, the energy equation now contains a heat source term due to energy transfer across the flow boundary or to work done through a shaft. The heat source term is treated fully explicitly. In addition, the equation of state is rewritten in terms of the quality and separate parameters for each phase. The models are simple enough to run quickly, yet include sufficient detail of dominant plant component characteristics to provide accurate results. 5 refs., 16 figs., 2 tabs

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

    DEFF Research Database (Denmark)

    Griskova, Inga; Mørup, Morten; Parnas, Josef

    2009-01-01

    Objective: To investigate the modulation of amplitude and phase precision of the auditory steady-state response (SSR) to 20 Hz stimulation in two conditions varying in the level of activation. Methods: Click stimuli (20 Hz) were applied while subjects were sitting upright silently reading a book...... of interest (high activation level) and while subjects were sitting in a reclined position with eyes closed and the lights turned off (low activation level). Sixty-one channel EEG data was wavelet transformed, the amplitude and phase precision measures extracted and decomposed by the multi-subject non......-negative multi-way factorization (NMWF). Results: The NMWF decomposition of amplitude and phase precision measures resulted in the observation of two distinct components: a component at the frequency of stimulation – 20 Hz SSR and a component emerging at 40 Hz – 20 Hz SSR-related 40 Hz activity. Modulation...

  12. Electroantennogram responses of grape borerXylotrechus pyrrhoderus bates (Coleoptera: Cerambycidae) to its male sex pheromone components.

    Science.gov (United States)

    Iwabuchi, K; Takahashi, J; Nakagawa, Y; Sakai, T

    1985-07-01

    Electroantennograms were recorded from the grape borerXylotrechus pyrrhoderus in response to serial dilutions of male sex pheromone components, (2S,3S)-octanediol and (2S)-hydroxy-3-octanone, and to 100 μg of their optical isomers and host plant substances. Female antennae always responded more strongly than male antennae. Antennae of both sexes were highly sensitive to (2S)-hydroxy-3-octanone. F/M ratio (female to male EAG value) was greater for male sex pheromone components, especially (2S,3S)-octanediol, and their optical isomers than plant substances. Antennal sensitivity to optical isomers (2R,3R-octanediol and 2S,3R-octanediol) was lower than true pheromone components.

  13. The Adolescent Coping Process Interview: Measuring Temporal and Affective Components of Adolescent Responses to Peer Stress

    OpenAIRE

    Gould, Laura Feagans; Hussong, Andrea M.; Keeley, Mary L.

    2007-01-01

    The way in which adolescents cope with stressors in their lives has been established as an important correlate of adjustment. While most theoretical models of coping entail unfolding transactions between coping strategies and emotional arousal, the majority of coping measures tap only trait-level coping styles, ignoring both temporal and affective components of the coping process. The current study fills this gap by establishing the psychometric properties of a newly developed measure, the Ad...

  14. Dynamic of consumer groups and response of commodity markets by principal component analysis

    Science.gov (United States)

    Nobi, Ashadun; Alam, Shafiqul; Lee, Jae Woo

    2017-09-01

    This study investigates financial states and group dynamics by applying principal component analysis to the cross-correlation coefficients of the daily returns of commodity futures. The eigenvalues of the cross-correlation matrix in the 6-month timeframe displays similar values during 2010-2011, but decline following 2012. A sharp drop in eigenvalue implies the significant change of the market state. Three commodity sectors, energy, metals and agriculture, are projected into two dimensional spaces consisting of two principal components (PC). We observe that they form three distinct clusters in relation to various sectors. However, commodities with distinct features have intermingled with one another and scattered during severe crises, such as the European sovereign debt crises. We observe the notable change of the position of two dimensional spaces of groups during financial crises. By considering the first principal component (PC1) within the 6-month moving timeframe, we observe that commodities of the same group change states in a similar pattern, and the change of states of one group can be used as a warning for other group.

  15. Nonlinear optical response induced by a second-harmonic electric-field component concomitant with optical near-field excitation

    Science.gov (United States)

    Yamaguchi, Maiku; Nobusada, Katsuyuki; Yatsui, Takashi

    2015-10-01

    Electron dynamics excited by an optical near field (ONF) in a two-dimensional quantum dot model was investigated by solving a time-dependent Schrödinger equation. It was found that the ONF excitation of the electron caused two characteristic phenomena: a two-photon absorption and an induction of a magnetic dipole moment with a strong third-harmonic component. By analyzing the interaction dynamics of the ONF and the electron, we explained that the physical mechanism underlying these phenomena was the second-harmonic electric-field component concomitant with the near-field excitation originating from the nonuniformity of the ONF. Despite a y -polarized ONF source, the second-harmonic component of an x -polarized electric field was inherently generated. The effect of the second-harmonic electric-field component is not due to usual second-order nonlinear response but appears only when we explicitly consider the electron dynamics interacting with the ONF beyond the conventional optical response assuming the dipole approximation.

  16. Parsimonious classification of binary lacunarity data computed from food surface images using kernel principal component analysis and artificial neural networks.

    Science.gov (United States)

    Iqbal, Abdullah; Valous, Nektarios A; Sun, Da-Wen; Allen, Paul

    2011-02-01

    Lacunarity is about quantifying the degree of spatial heterogeneity in the visual texture of imagery through the identification of the relationships between patterns and their spatial configurations in a two-dimensional setting. The computed lacunarity data can designate a mathematical index of spatial heterogeneity, therefore the corresponding feature vectors should possess the necessary inter-class statistical properties that would enable them to be used for pattern recognition purposes. The objectives of this study is to construct a supervised parsimonious classification model of binary lacunarity data-computed by Valous et al. (2009)-from pork ham slice surface images, with the aid of kernel principal component analysis (KPCA) and artificial neural networks (ANNs), using a portion of informative salient features. At first, the dimension of the initial space (510 features) was reduced by 90% in order to avoid any noise effects in the subsequent classification. Then, using KPCA, the first nineteen kernel principal components (99.04% of total variance) were extracted from the reduced feature space, and were used as input in the ANN. An adaptive feedforward multilayer perceptron (MLP) classifier was employed to obtain a suitable mapping from the input dataset. The correct classification percentages for the training, test and validation sets were 86.7%, 86.7%, and 85.0%, respectively. The results confirm that the classification performance was satisfactory. The binary lacunarity spatial metric captured relevant information that provided a good level of differentiation among pork ham slice images. Copyright © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

  17. Near-surface groundwater responses to injection of geothermal wastes

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, S.C.

    1984-06-01

    Experiences with injecting geothermal fluids have identified technical problems associated with geothermal waste disposal. This report assesses the feasibility of injection as an alternative for geothermal wastewater disposal and analyzes hydrologic controls governing the upward migration of injected fluids. Injection experiences at several geothermal developments are presented, including: Raft River, Salton Sea, East Mesa, Otake and Hatchobaru in Japan, and Ahuachapan in El Salvador. Hydrogeologic and design/operational factors affecting the success of an injection program are identified. Hydrogeologic factors include subsidence, near-surface effects of injected fluids, and seismicity. Design/operational factors include hydrodynamic breakthrough, condition of the injection system and reservoir maintenance. Existing and potential effects of production/injection on these factors are assessed.

  18. Tracing the stellar component of low surface brightness Milky Way dwarf galaxies to their outskirts. I. Sextans

    Science.gov (United States)

    Cicuéndez, L.; Battaglia, G.; Irwin, M.; Bermejo-Climent, J. R.; McMonigal, B.; Bate, N. F.; Lewis, G. F.; Conn, A. R.; de Boer, T. J. L.; Gallart, C.; Guglielmo, M.; Ibata, R.; McConnachie, A.; Tolstoy, E.; Fernando, N.

    2018-01-01

    Aims: We present results from deep and very spatially extended CTIO/DECam g and r photometry (reaching out to 2 mag below the oldest main-sequence turn-off and covering 20 deg2) around the Sextans dwarf spheroidal galaxy. We aim to use this dataset to study the structural properties of Sextans overall stellar population and its member stars in different evolutionary phases, as well as to search for possible signs of tidal disturbance from the Milky Way, which would indicate departure from dynamical equilibrium. Methods: We performed the most accurate and quantitative structural analysis to-date of Sextans' stellar components by applying Bayesian Monte Carlo Markov chain methods to the individual stars' positions. Surface density maps are built by statistically decontaminating the sample through a matched filter analysis of the colour-magnitude diagram, and then analysed for departures from axisymmetry. Results: Sextans is found to be significantly less spatially extended and more centrally concentrated than early studies suggested. No statistically significant distortions or signs of tidal disturbances were found down to a surface brightness limit of 31.8 mag/arcsec2 in V-band. We identify an overdensity in the central regions that may correspond to previously reported kinematic substructure(s). In agreement with previous findings, old and metal-poor stars such as Blue Horizontal Branch stars cover a much larger area than stars in other evolutionary phases, and bright Blue Stragglers (BSs) are less spatially extended than faint ones. However, the different spatial distribution of bright and faint BSs appears consistent with the general age and metallicity gradients found in Sextans' stellar component. This is compatible with Sextans BSs having formed by evolution of binaries and not necessarily due to the presence of a central disrupted globular cluster, as suggested in the literature. We provide structural parameters for the various populations analysed and make

  19. Measuring localized nonlinear components in a circular accelerator with a nonlinear tune response matrix

    Directory of Open Access Journals (Sweden)

    G. Franchetti

    2008-09-01

    Full Text Available In this paper we present a method for measuring the nonlinear errors in a circular accelerator by taking advantage of the feed-down effect of high order multipoles when the closed orbit is globally deformed. We devise a nonlinear tune response matrix in which the response to a closed orbit deformation is obtained in terms of change of machine tune and correlated with the strength of the local multipoles. A numerical example and a proof of principle experiment to validate the theoretical methods are presented and discussed.

  20. Applicability of Equivalent Static Method to seismic response of piping and other components

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, B.J.

    1993-02-01

    The Equivalent Static Method (ESM) is a simple and cost effective approach in the design of systems and components subjected to seismic loads. However, its applicability is restricted to systems which can be represented by a simple model.'' In this paper the restriction to a simple model is examined using the example of a propped cantilever, for which some codes or standards explicitly state that ESM is not applicable. By comparing ESM results for the propped cantilever with those for a regular (un-propped) cantilever, it is found that ESM can conditionally be applied to the propped cantilever configuration.

  1. Applicability of Equivalent Static Method to seismic response of piping and other components

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, B.J.

    1993-02-01

    The Equivalent Static Method (ESM) is a simple and cost effective approach in the design of systems and components subjected to seismic loads. However, its applicability is restricted to systems which can be represented by a ``simple model.`` In this paper the restriction to a simple model is examined using the example of a propped cantilever, for which some codes or standards explicitly state that ESM is not applicable. By comparing ESM results for the propped cantilever with those for a regular (un-propped) cantilever, it is found that ESM can conditionally be applied to the propped cantilever configuration.

  2. Prediction of resistance development against drug combinations by collateral responses to component drugs

    DEFF Research Database (Denmark)

    Munck, Christian; Gumpert, Heidi; Nilsson Wallin, Annika

    2014-01-01

    the genomes of all evolved E. coli lineages, we identified the mutational events that drive the differences in drug resistance levels and found that the degree of resistance development against drug combinations can be understood in terms of collateral sensitivity and resistance that occurred during...... adaptation to the component drugs. Then, using engineered E. coli strains, we confirmed that drug resistance mutations that imposed collateral sensitivity were suppressed in a drug pair growth environment. These results provide a framework for rationally selecting drug combinations that limit resistance...

  3. Bacterial Cell Wall Components

    Science.gov (United States)

    Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

    Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

  4. A new response surface approach for structural reliability analysis

    Science.gov (United States)

    Thacker, B. H.; Wu, X.-T.

    1992-01-01

    This paper describes a new approach for computing structural reliability by post-processing previously computed probabilistic results for stress and strength. The objective is to provide an accurate method whereby independent probabilistic analyses for stress and strength functions can be performed independently and combined at a later time to compute probability of failure. The method provides a capability for testing different strength measures without the need for re-computing the probabilistic stress response. The proposed approach takes full account of the basic random variables effecting both stress and strength, and the failure region in the variable space identified during separate stress/strength probabilistic analyses. A simple closed-form example and a more complex analysis of a turbine blade subject to creep rupture is used to illustrate the method.

  5. Response on the earth surface due to illumination by electromagnetic pulse of nuclear explosion

    International Nuclear Information System (INIS)

    Nesic, R.

    1983-01-01

    Electromagnetic pulse is one of environment responses to extitation by nuclear explosion, its influence on the surface of the earth is most expressed in case of a nuclear explosion in ionosphere. For electromagnetic pulse of ionospheric explosion the time response, spectrum, spectral distribution and integral flux of energy on the earth surface were analysed, responses to them in shape of conductive voltage and currents were defined. Obtained shapes of responses and their range of variation are the base to define requirements for needed and justified protections. (author)

  6. Previously published midazolam-alfentanil response surface model cannot predict patient response well in gastrointestinal endoscopy sedation.

    Science.gov (United States)

    Liou, Jing-Yang; Ting, Chien-Kun; Huang, Yu-Ying; Tsou, Mei-Yung

    2016-03-01

    A response surface model is a mathematical model used to predict multiple-drug pharmacodynamic interactions. With the use of a previously published volunteer model, we tested the accuracy of the midazolam-alfentanil response surface model during gastrointestinal endoscopy. We enrolled 35 adult patients scheduled for combined endoscopic procedures. Patients were sedated with intravenous midazolam and alfentanil, and monitored with real-time auditory evoked potential. Sedation Observer's Assessment of Alertness/Sedation (OAA/S) scores were recorded by an independent observer every 2 minutes. Patients with OAA/S scores of ≥ 4 were designated as "awake". Pharmacokinetic profiles were calculated using the TIVA trainer. The published response surface model was modified to make estimations more reasonable. Patient response (OAA/S score ≥ 4 or response during gastrointestinal endoscopic procedure sedation. Accuracy in predicting an OAA/S score of response ranged from 0.04% to 2.94% at the time of arousal (OAA/S score ≥ 4) and from 0.24% to 15.55% when the patient was asleep (OAA/S score response of patients undergoing sedated gastrointestinal endoscopic procedures. Future model parameter adjustments are required. Copyright © 2016. Published by Elsevier Taiwan LLC.

  7. Training Teachers to Use Pivotal Response Training with Children with Autism: Coaching as a Critical Component

    Science.gov (United States)

    Suhrheinrich, Jessica

    2011-01-01

    Although evidence-based practices (EBPs) for educating children with autism, such as pivotal response training (PRT), exist, teachers often lack adequate training to use these practices. The current investigation examined the efficacy of a 6-hour group workshop plus individual coaching for training 20 teachers to use PRT. Results indicate that the…

  8. Pericranial muscular, respiratory, and heart rate components of the orienting response

    NARCIS (Netherlands)

    Stekelenburg, J.J.; van Boxtel, A.

    2002-01-01

    We have earlier found that voluntary attention to weak auditory stimuli induces inhibition of respiration, heart rate, and electromyographic (EMG) activity of masticatory and lower facial muscles and that these responses lower the auditory threshold for low-frequency sounds. In the current study, we

  9. Decoupling the response of an estuarine shrimp to architectural components of habitat structure.

    Science.gov (United States)

    Crooks, Jeffrey A; Chang, Andrew L; Ruiz, Gregory M

    2016-01-01

    In order to explore biotic attraction to structure, we examined how the amount and arrangement of artificial biotic stalks affected responses of a shrimp, Palaemon macrodactylus, absent other proximate factors such as predation or interspecific competition. In aquaria, we tested the effect of differing densities of both un-branched and branched stalks, where the amount of material in the branched stalk equaled four-times that of the un-branched. The results clearly showed that it was the amount of material, not how it was arranged, that elicited responses from shrimp. Also, although stalks were not purposefully designed to mimic structural elements found in nature, they did resemble biogenic structure such as hydroids, algae, or plants. In order to test shrimp attraction to a different, perhaps more unfamiliar habitat type, we examined responses to plastic "army men." These structural elements elicited similar attraction of shrimp, and, in general, shrimp response correlated well with the fractal dimension of both stalks and army men. Overall, these results indicate that attraction to physical structure, regardless of its nature, may be an important driver of high abundances often associated with complex habitats.

  10. Decoupling the response of an estuarine shrimp to architectural components of habitat structure

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Crooks

    2016-08-01

    Full Text Available In order to explore biotic attraction to structure, we examined how the amount and arrangement of artificial biotic stalks affected responses of a shrimp, Palaemon macrodactylus, absent other proximate factors such as predation or interspecific competition. In aquaria, we tested the effect of differing densities of both un-branched and branched stalks, where the amount of material in the branched stalk equaled four-times that of the un-branched. The results clearly showed that it was the amount of material, not how it was arranged, that elicited responses from shrimp. Also, although stalks were not purposefully designed to mimic structural elements found in nature, they did resemble biogenic structure such as hydroids, algae, or plants. In order to test shrimp attraction to a different, perhaps more unfamiliar habitat type, we examined responses to plastic “army men.” These structural elements elicited similar attraction of shrimp, and, in general, shrimp response correlated well with the fractal dimension of both stalks and army men. Overall, these results indicate that attraction to physical structure, regardless of its nature, may be an important driver of high abundances often associated with complex habitats.

  11. Response of Yield and Yield Components of Field Pea to Tillage ...

    African Journals Online (AJOL)

    The results indicated a highly significant positive response of mean field pea seed yield, total biomass and number of pods per plant to tillage frequency, phosphorus fertilizer and weeding treatments. Plowing twice, three and four times including the last pass for seed covering resulted in mean seed yield advantages of 38, ...

  12. Yield components and quality of intercropped cotton in response to mepiquat chloride and plant density

    NARCIS (Netherlands)

    Mao, Lili; Zhang, Lizhen; Evers, J.B.; Werf, van der Wopke; Liu, Shaodong; Zhang, Siping; Wang, Baomin; Li, Zhaohu

    2015-01-01

    Cotton yield is greatly improved by moderately increasing plant density and modifying the cotton plants to have a compact structure, which is also required by the increasing demand for mechanized harvest. However, in cotton strip intercropped with wheat, only limited knowledge on yield response

  13. An Empirical Correction Method for Improving off-Axes Response Prediction in Component Type Flight Mechanics Helicopter Models

    Science.gov (United States)

    Mansur, M. Hossein; Tischler, Mark B.

    1997-01-01

    Historically, component-type flight mechanics simulation models of helicopters have been unable to satisfactorily predict the roll response to pitch stick input and the pitch response to roll stick input off-axes responses. In the study presented here, simple first-order low-pass filtering of the elemental lift and drag forces was considered as a means of improving the correlation. The method was applied to a blade-element model of the AH-64 APache, and responses of the modified model were compared with flight data in hover and forward flight. Results indicate that significant improvement in the off-axes responses can be achieved in hover. In forward flight, however, the best correlation in the longitudinal and lateral off-axes responses required different values of the filter time constant for each axis. A compromise value was selected and was shown to result in good overall improvement in the off-axes responses. The paper describes both the method and the model used for its implementation, and presents results obtained at hover and in forward flight.

  14. Borrelia burgdorferi outer surface protein C (OspC) binds complement component C4b and confers bloodstream survival.

    Science.gov (United States)

    Caine, Jennifer A; Lin, Yi-Pin; Kessler, Julie R; Sato, Hiromi; Leong, John M; Coburn, Jenifer

    2017-12-01

    Borrelia burgdorferi (Bb) is the causative agent of Lyme disease in the United States, a disease that can result in carditis, and chronic and debilitating arthritis and/or neurologic symptoms if left untreated. Bb survives in the midgut of the Ixodes scapularis tick, or within tissues of immunocompetent hosts. In the early stages of infection, the bacteria are present in the bloodstream where they must resist clearance by the innate immune system of the host. We have found a novel role for outer surface protein C (OspC) from B. burgdorferi and B. garinii in interactions with the complement component C4b and bloodstream survival in vivo. Our data show that OspC inhibits the classical and lectin complement pathways and competes with complement protein C2 for C4b binding. Resistance to complement is important for maintenance of the lifecycle of Bb, enabling survival of the pathogen within the host as well as in the midgut of a feeding tick when ospC expression is induced. © 2017 John Wiley & Sons Ltd.

  15. Simulation of Time-Varying Spatially Uniform Pressure and Near-Surface Wind Flows on Building Components and Cladding

    Directory of Open Access Journals (Sweden)

    Seraphy Y. Shen

    2017-05-01

    Full Text Available This paper describes a new full-scale (FS testing apparatus for conducting performance evaluations of FS building envelope systems. The simulator can generate spatially uniform, time-varying pressure conditions associated with Saffir–Simpson Hurricane Wind Scale Category 5 winds while compensating for large air leakage through the specimen and also operate a high-speed wind tunnel, both with dynamic control. This paper presents system details, operating characteristics, and an early case study on the performance of large sectional door systems under wind pressure loading. Failure mechanisms are discussed, and finite element modeling is validated for two specimens. It demonstrates successful dynamic load control for large component and cladding systems, as well as simulation of flows near the building surface. These capabilities serve to complement other FS wind tunnel facilities by offering tools to generate ultimate load conditions on portions of the building. Further, the paper successfully demonstrates the utility of combining physical testing and computational analysis as a matter of routine, which underscores the potential of evolving FS testing to encompass cyber–physical approaches.

  16. An Improved Response Surface Methodology Algorithm with an Application to Traffic Signal Optimization for Urban Networks

    Science.gov (United States)

    1995-01-01

    Prepared ca. 1995. This paper illustrates the use of the simulation-optimization technique of response surface methodology (RSM) in traffic signal optimization of urban networks. It also quantifies the gains of using the common random number (CRN) va...

  17. Comparison of Response Surface and Kriging Models in the Multidisciplinary Design of an Aerospike Nozzle

    Science.gov (United States)

    Simpson, Timothy W.

    1998-01-01

    The use of response surface models and kriging models are compared for approximating non-random, deterministic computer analyses. After discussing the traditional response surface approach for constructing polynomial models for approximation, kriging is presented as an alternative statistical-based approximation method for the design and analysis of computer experiments. Both approximation methods are applied to the multidisciplinary design and analysis of an aerospike nozzle which consists of a computational fluid dynamics model and a finite element analysis model. Error analysis of the response surface and kriging models is performed along with a graphical comparison of the approximations. Four optimization problems are formulated and solved using both approximation models. While neither approximation technique consistently outperforms the other in this example, the kriging models using only a constant for the underlying global model and a Gaussian correlation function perform as well as the second order polynomial response surface models.

  18. Structural response of near surface mounted CFRP strengthened reinforced concrete bridge deck overhang.

    Science.gov (United States)

    2008-11-01

    This report presents the results from an experimental investigation which explores the change in structural response due to the addition of near-surface-mounted (NSM) carbon fiber reinforced polymer (CFRP) reinforcement for increasing the capacity of...

  19. Comparison of Response Surface and Kriging Models for Multidisciplinary Design Optimization

    Science.gov (United States)

    Simpson, Timothy W.; Korte, John J.; Mauery, Timothy M.; Mistree, Farrokh

    1998-01-01

    In this paper, we compare and contrast the use of second-order response surface models and kriging models for approximating non-random, deterministic computer analyses. After reviewing the response surface method for constructing polynomial approximations, kriging is presented as an alternative approximation method for the design and analysis of computer experiments. Both methods are applied to the multidisciplinary design of an aerospike nozzle which consists of a computational fluid dynamics model and a finite-element model. Error analysis of the response surface and kriging models is performed along with a graphical comparison of the approximations, and four optimization problems m formulated and solved using both sets of approximation models. The second-order response surface models and kriging models-using a constant underlying global model and a Gaussian correlation function-yield comparable results.

  20. Stochastic response surface methodology: A study in the human health area

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Teresa A., E-mail: teresa.oliveira@uab.pt; Oliveira, Amílcar, E-mail: amilcar.oliveira@uab.pt [Departamento de Ciências e Tecnologia, Universidade Aberta (Portugal); Centro de Estatística e Aplicações, Universidade de Lisboa (Portugal); Leal, Conceição, E-mail: conceicao.leal2010@gmail.com [Departamento de Ciências e Tecnologia, Universidade Aberta (Portugal)

    2015-03-10

    In this paper we review Stochastic Response Surface Methodology as a tool for modeling uncertainty in the context of Risk Analysis. An application in the survival analysis in the breast cancer context is implemented with R software.

  1. Discovery of a low order drug-cell response surface for applications in personalized medicine

    International Nuclear Information System (INIS)

    Ding, Xianting; Liu, Wenjia; Li, Yiyang; Weiss, Andrea; Van den Bergh, Hubert; Nowak-Sliwinska, Patrycja; Wong, Ieong; Ho, Chih-Ming; Griffioen, Arjan W; Xu, Hongquan

    2014-01-01

    The cell is a complex system involving numerous components, which may often interact in a non-linear dynamic manner. Diseases at the cellular level are thus likely to involve multiple cellular constituents and pathways. As some drugs, or drug combinations, may act synergistically on these multiple pathways, they might be more effective than the respective single target agents. Optimizing a drug mixture for a given disease in a particular patient is particularly challenging due to both the difficulty in the selection of the drug mixture components to start out with, and the all-important doses of these drugs to be applied. For n concentrations of m drugs, in principle, n m combinations will have to be tested. As this may lead to a costly and time-consuming investigation for each individual patient, we have developed a Feedback System Control (FSC) technique which can rapidly select the optimal drug–dose combination from the often millions of possible combinations. By testing this FSC technique in a number of experimental systems representing different disease states, we found that the response of cells to multiple drugs is well described by a low order, rather smooth, drug-mixture-input/drug-effect-output multidimensional surface. The main consequences of this are that optimal drug combinations can be found in a surprisingly small number of tests, and that translation from in vitro to in vivo is simplified. This points to the possibility of personalized optimal drug mixtures in the near future. This unexpectedly simple input–output relationship may also lead to a simple solution for handling the issue of human diversity in cancer therapeutics. (paper)

  2. Prediction of material removal rate and surface roughness for wire electrical discharge machining of nickel using response surface methodology

    Directory of Open Access Journals (Sweden)

    Thangam Chinnadurai

    2016-12-01

    Full Text Available This study focuses on investigating the effects of process parameters, namely, Peak current (Ip, Pulse on time (Ton, Pulse off time (Toff, Water pressure (Wp, Wire feed rate (Wf, Wire tension (Wt, Servo voltage (Sv and Servo feed setting (Sfs, on the Material Removal Rate (MRR and Surface Roughness (SR for Wire electrical discharge machining (Wire-EDM of nickel using Taguchi method. Response Surface Methodology (RSM is adopted to evolve mathematical relationships between the wire cutting process parameters and the output variables of the weld joint to determine the welding input parameters that lead to the desired optimal wire cutting quality. Besides, using response surface plots, the interaction effects of process parameters on the responses are analyzed and discussed. The statistical software Mini-tab is used to establish the design and to obtain the regression equations. The developed mathematical models are tested by analysis-of-variance (ANOVA method to check their appropriateness and suitability. Finally, a comparison is made between measured and calculated results, which are in good agreement. This indicates that the developed models can predict the responses accurately and precisely within the limits of cutting parameter being used.

  3. Prediction of material removal rate and surface roughness for wire electrical discharge machining of nickel using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Chinnadurai, T.; Vendan, S.A.

    2016-07-01

    This study focuses on investigating the effects of process parameters, namely, Peak current (Ip), Pulse on time (Ton), Pulse off time (Toff), Water pressure (Wp), Wire feed rate (Wf), Wire tension (Wt), Servo voltage (Sv) and Servo feed setting (Sfs), on the Material Removal Rate (MRR) and Surface Roughness (SR) for Wire electrical discharge machining (Wire-EDM) of nickel using Taguchi method. Response Surface Methodology (RSM) is adopted to evolve mathematical relationships between the wire cutting process parameters and the output variables of the weld joint to determine the welding input parameters that lead to the desired optimal wire cutting quality. Besides, using response surface plots, the interaction effects of process parameters on the responses are analyzed and discussed. The statistical software Mini-tab is used to establish the design and to obtain the regression equations. The developed mathematical models are tested by analysis-of-variance (ANOVA) method to check their appropriateness and suitability. Finally, a comparison is made between measured and calculated results, which are in good agreement. This indicates that the developed models can predict the responses accurately and precisely within the limits of cutting parameter being used. (Author)

  4. Response Surface Model Building and Multidisciplinary Optimization Using D-Optimal Designs

    Science.gov (United States)

    Unal, Resit; Lepsch, Roger A.; McMillin, Mark L.

    1998-01-01

    This paper discusses response surface methods for approximation model building and multidisciplinary design optimization. The response surface methods discussed are central composite designs, Bayesian methods and D-optimal designs. An over-determined D-optimal design is applied to a configuration design and optimization study of a wing-body, launch vehicle. Results suggest that over determined D-optimal designs may provide an efficient approach for approximation model building and for multidisciplinary design optimization.

  5. Investigation of Compost Fertilizer Granulation Parameters Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Y Ghasemi

    2015-03-01

    Full Text Available Nowadays compost fertilizers are suitable alternative to chemical fertilizers, due to the threats for human health and agriculture products. The most important problems for applying the compost fertilizer in the farm are: transportation (high volume, high moisture content, spreading problem, impurity such as dust and storage. To solve the problems mentioned, pressing process such as converting the compost to pellets and granules are suggested. In this research the effects of some granulation parameters on the percent of useful granules in a laboratory scale rotating drum was evaluated. The percentage of useful granules decreased by increasing the granulation time and increased by increasing the percentage of drum filling. The optimal conditions for granules production was achieved at drum rotational speed of 40.38 rpm, granulation time of 15 min, drum filling of 10% and molasse percentage of 40.97. According to these conditions, the response for useful granule was estimated as 81.6% with R2 of 0.924.

  6. The Adolescent Coping Process Interview: measuring temporal and affective components of adolescent responses to peer stress.

    Science.gov (United States)

    Feagans Gould, Laura; Hussong, Andrea M; Keeley, Mary L

    2008-10-01

    The way in which adolescents cope with stressors in their lives has been established as an important correlate of adjustment. While most theoretical models of coping entail unfolding transactions between coping strategies and emotional arousal, the majority of coping measures tap only trait-level coping styles, ignoring both temporal and affective components of the coping process. The current study fills this gap by establishing the psychometric properties of a newly developed measure, the Adolescent Coping Process Interview (ACPI), that is more in line with transactional and developmental models of coping. Results indicate that the ACPI displays good psychometric properties, captures significant intra-individual variability in coping over the process, and points to emotional arousal as informing several coping-adjustment relationships. Moreover, the ACPI and similar approaches may help promote the development of more adaptive patterns of coping in adolescents by helping to identify specific points within the coping process at which to intervene.

  7. 2015 Workplace and Gender Relations Survey of Reserve Component Members: Tabulations of Responses

    Science.gov (United States)

    2016-03-17

    environment and sexual quid pro quo) and/or the gender discrimination prevalence rate...frame of “12 months prior to taking the survey.”4 3. Gender-Related MEO Violations—Experiences of MEO violations ( discrimination and sexual ...for sexual harassment, gender discrimination , and sexual assault to tailor question stems and survey responses to each respondent based on his/her

  8. Effect of nanocoating with rhamnogalacturonan-I on surface properties and osteoblasts response

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna Aleksandra; Svava, Rikke; Syberg, Susanne

    2012-01-01

    -I) on surface properties and osteoblasts response. Three different RG-Is from apple and lupin pectins were modified and coated on amino-functionalized tissue culture polystyrene plates (aminated TCPS). Surface properties were evaluated by scanning electron microscopy, contact angle measurement, atomic force...

  9. Homogenate Extraction of Crocins from Saffron Optimized by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Yingpeng Tong

    2018-01-01

    Full Text Available Saffron, which has many kinds of biological activities, has been widely used in medicine, cosmetics, food, and other fields of health promotion industries. Crocins are the main component of saffron (Crocus sativus L.. At present, most of the extraction methods for crocins require long time or special instruments to complete the process and some of them are not suitable for industrial production at present. In this article, homogenate extraction technology which is a convenient and efficient method was developed for crocins extraction from saffron. Firstly, the influences of extraction voltage, extraction time, ethanol concentration, and temperature on crocins yield were studied by single factor experiments; and then response surface methodology (RSM was used to optimize levels of four variables based on the result of single factor experiments. Results showed that the optimum extraction process conditions for crocins were as follows: extraction voltage, 110 V; ethanol concentration, 70%; extraction temperature, 57°C; and extraction time, 40 s. Based on these conditions, the extraction yield of crocins can reach 22.76% which is higher than ultrasonic extraction method. Therefore, homogenate extraction is an effective way to extract crocins from saffron with higher extraction yield and shorter extraction time.

  10. Characterization of Lactococcus lactis response to ampicillin and ciprofloxacin using surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Wang, Panxue; Pang, Shintaro; Zhang, Hua; Fan, Mingtao; He, Lili

    2016-01-01

    Decades of antibiotic use or misuse has resulted in antibiotic resistance in lactic acid bacteria, a group of common culture starters and probiotic microorganisms. This has urged researchers to study how lactic acid bacteria respond to antibiotics, so as to have a better strategy to identify and predict the antibiotic-resistant bacteria. This study aimed to characterize the biochemical profiles of Lactococcus lactis responding to antibiotics using surface-enhanced Raman spectroscopy (SERS). Lactococcus lactis exposed to antibiotics was mixed with 50-nm gold nanoparticles for subsequent SERS measurements. The SERS spectra analyzed by principal component analysis showed no significant change after 30 min of antibiotic treatment, whereas distinct changes were clearly observed after 60 and 90 min of antibiotic treatment. Different antibiotics induced different spectral changes, and these changes revealed the detailed biochemical information of cellular responses. This study demonstrates that the SERS method developed not only senses the changes in the bacterial cell wall, but also reveals details of the biochemical profiles, which help us to understand how lactic acid bacteria respond to antibiotics, as well as to set a base for the detection of antibiotic susceptibility of bacteria by SERS.

  11. Optimization of ultrasound-assisted extraction of charantin from Momordica charantia fruits using response surface methodology.

    Science.gov (United States)

    Ahamad, Javed; Amin, Saima; Mir, Showkat R

    2015-01-01

    Momordica charantia Linn. (Cucurbitaceae) fruits are well known for their beneficial effects in diabetes that are often attributed to its bioactive component charantin. The aim of the present study is to develop and optimize an efficient protocol for the extraction of charantin from M. charantia fruits. Response surface methodology (RSM) was used for the optimization of ultrasound-assisted extraction (UAE) conditions. RSM was based on a three-level, three-variable Box-Behnken design (BBD), and the studied variables included solid to solvent ratio, extraction temperature, and extraction time. The optimal conditions predicted by the BBD were: UAE with methanol: Water (80:20, v/v) at 46°C for 120 min with solid to solvent ratio of 1:26 w/v, under which the yield of charantin was 3.18 mg/g. Confirmation trials under slightly adjusted conditions yielded 3.12 ± 0.14 mg/g of charantin on dry weight basis of fruits. The result of UAE was also compared with Soxhlet extraction method and UAE was found 2.74-fold more efficient than the Soxhlet extraction for extracting charantin. A facile UAE protocol for a high extraction yield of charantin was developed and validated.

  12. Enhanced Production of Xylitol from Corncob by Pachysolen tannophilus Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    S. Ramesh

    2013-01-01

    Full Text Available Optimization of the culture medium and process variables for xylitol production using corncob hemicellulose hydrolysate by Pachysolen tannophilus (MTTC 1077 was performed with statistical methodology based on experimental designs. The screening of nine nutrients for their influence on xylitol production was achieved using a Plackett-Burman design. Peptone, xylose, MgSO4·7H2O, and yeast extract were selected based on their positive influence on xylitol production. The selected components were optimized with Box-Behnken design using response surface methodology (RSM. The optimum levels (g/L were peptone: 6.03, xylose: 10.62, MgSO4·7H2O: 1.39, yeast extract: 4.66. The influence of various process variables on the xylitol production was evaluated. The optimal levels of these variables were quantified by the central composite design using RSM, for establishment of a significant mathematical model with a coefficient determination of . The validation experimental was consistent with the prediction model. The optimum levels of process variables were temperature (36.56°C, pH (7.27, substrate concentration (3.55 g/L, inoculum size (3.69 mL, and agitation speed (194.44 rpm. These conditions were validated experimentally which revealed an enhanced xylitol yield of 0.80 g/g.

  13. Optimization of ultrasound-assisted extraction of charantin from Momordica charantia fruits using response surface methodology

    Directory of Open Access Journals (Sweden)

    Javed Ahamad

    2015-01-01

    Full Text Available Background: Momordica charantia Linn. (Cucurbitaceae fruits are well known for their beneficial effects in diabetes that are often attributed to its bioactive component charantin. Objective: The aim of the present study is to develop and optimize an efficient protocol for the extraction of charantin from M. charantia fruits. Materials and Methods: Response surface methodology (RSM was used for the optimization of ultrasound-assisted extraction (UAE conditions. RSM was based on a three-level, three-variable Box-Behnken design (BBD, and the studied variables included solid to solvent ratio, extraction temperature, and extraction time. Results: The optimal conditions predicted by the BBD were: UAE with methanol: Water (80:20, v/v at 46°C for 120 min with solid to solvent ratio of 1:26 w/v, under which the yield of charantin was 3.18 mg/g. Confirmation trials under slightly adjusted conditions yielded 3.12 ± 0.14 mg/g of charantin on dry weight basis of fruits. The result of UAE was also compared with Soxhlet extraction method and UAE was found 2.74-fold more efficient than the Soxhlet extraction for extracting charantin. Conclusions:A facile UAE protocol for a high extraction yield of charantin was developed and validated.

  14. Optimization of ultrasound-assisted extraction of charantin from Momordica charantia fruits using response surface methodology

    Science.gov (United States)

    Ahamad, Javed; Amin, Saima; Mir, Showkat R.

    2015-01-01

    Background: Momordica charantia Linn. (Cucurbitaceae) fruits are well known for their beneficial effects in diabetes that are often attributed to its bioactive component charantin. Objective: The aim of the present study is to develop and optimize an efficient protocol for the extraction of charantin from M. charantia fruits. Materials and Methods: Response surface methodology (RSM) was used for the optimization of ultrasound-assisted extraction (UAE) conditions. RSM was based on a three-level, three-variable Box-Behnken design (BBD), and the studied variables included solid to solvent ratio, extraction temperature, and extraction time. Results: The optimal conditions predicted by the BBD were: UAE with methanol: Water (80:20, v/v) at 46°C for 120 min with solid to solvent ratio of 1:26 w/v, under which the yield of charantin was 3.18 mg/g. Confirmation trials under slightly adjusted conditions yielded 3.12 ± 0.14 mg/g of charantin on dry weight basis of fruits. The result of UAE was also compared with Soxhlet extraction method and UAE was found 2.74-fold more efficient than the Soxhlet extraction for extracting charantin. Conclusions: A facile UAE protocol for a high extraction yield of charantin was developed and validated. PMID:26681889

  15. Application of response surface methodology to enhancement of biomass production by Lactobacillus rhamnosus E/N

    Directory of Open Access Journals (Sweden)

    Magdalena Polak-Berecka

    2011-12-01

    Full Text Available Response surface methodology (RSM was employed to study the effects of various medium components on biomass production by Lactobacillus rhamnosus E/N. This strain is commonly used in the pharmaceutical and food industries due to its beneficial effect on the human gut and general health. The best medium composition derived from RSM regression was (in g/l glucose 15.44, sodium pyruvate 3.92, meat extract 8.0, potassium phosphate 1.88, sodium acetate 4.7, and ammonium citrate 1.88. With this medium composition biomass production was 23 g/l of dry cell weight after 18 h of cultivation in bioreactor conditions, whereas on MRS the yield of biomass was 21 g/l of dry cell weight. The cost of 1 g of biomass obtained on MRS broth was calculated at the level of 0.44 € whereas on the new optimal medium it was 25% lower. It may be concluded then, that the new medium, being cheaper than the control MRS allows large scale commercial cultivation of the L. rhamnosus strain. This study is of relevance to food industry because the possibility to obtain high yield of bacterial biomass is necessary step in manufacturing of probiotic food.

  16. Expression of secreted Wnt pathway components reveals unexpected complexity of the planarian amputation response.

    Science.gov (United States)

    Gurley, Kyle A; Elliott, Sarah A; Simakov, Oleg; Schmidt, Heiko A; Holstein, Thomas W; Sánchez Alvarado, Alejandro

    2010-11-01

    Regeneration is widespread throughout the animal kingdom, but our molecular understanding of this process in adult animals remains poorly understood. Wnt/β-catenin signaling plays crucial roles throughout animal life from early development to adulthood. In intact and regenerating planarians, the regulation of Wnt/β-catenin signaling functions to maintain and specify anterior/posterior (A/P) identity. Here, we explore the expression kinetics and RNAi phenotypes for secreted members of the Wnt signaling pathway in the planarian Schmidtea mediterranea. Smed-wnt and sFRP expression during regeneration is surprisingly dynamic and reveals fundamental aspects of planarian biology that have been previously unappreciated. We show that after amputation, a wounding response precedes rapid re-organization of the A/P axis. Furthermore, cells throughout the body plan can mount this response and reassess their new A/P location in the complete absence of stem cells. While initial stages of the amputation response are stem cell independent, tissue remodeling and the integration of a new A/P address with anatomy are stem cell dependent. We also show that WNT5 functions in a reciprocal manner with SLIT to pattern the planarian mediolateral axis, while WNT11-2 patterns the posterior midline. Moreover, we perform an extensive phylogenetic analysis on the Smed-wnt genes using a method that combines and integrates both sequence and structural alignments, enabling us to place all nine genes into Wnt subfamilies for the first time. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. Serum and skin surface antibody responses in merino sheep given three successive inoculations with Dermatophilus congolensis.

    Science.gov (United States)

    Sutherland, S S; Ellis, T M; Robertson, G M; Gregory, A R

    1987-11-01

    Three antigens prepared from different phases of the life cycle of Dermatophilus congolensis were used in an enzyme-linked immunosorbent assay to measure serum and skin surface antibody responses in sheep after a first, second and third inoculation with D. congolensis. After the first inoculation, a strong antibody response to the flagella, filament and soluble antigens was detected after 7-21 days in the sera from sheep that were regularly biopsied; the antibody response at the skin surface was detected 28-42 days after inoculation, when the lesions were resolving. Strong anamnestic responses were detected in the serum of sheep that were biopsied and some of the nonbiopsied sheep after the second and third inoculations, but the skin surface antibody response at these times was variable.

  18. An Effective Vacuum Assisted Extraction Method for the Optimization of Labdane Diterpenoids from Andrographis paniculata by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Ya-Qi Wang

    2014-12-01

    Full Text Available An effective vacuum assisted extraction (VAE technique was proposed for the first time and applied to extract bioactive components from Andrographis paniculata. The process was carefully optimized by response surface methodology (RSM. Under the optimized experimental conditions, the best results were obtained using a boiling temperature of 65 °C, 50% ethanol concentration, 16 min of extraction time, one extraction cycles and a 12:1 liquid-solid ratio. Compared with conventional ultrasonic assisted extraction and heat reflux extraction, the VAE technique gave shorter extraction times and remarkable higher extraction efficiency, which indicated that a certain degree of vacuum gave the solvent a better penetration of the solvent into the pores and between the matrix particles, and enhanced the process of mass transfer. The present results demonstrated that VAE is an efficient, simple and fast method for extracting bioactive components from A. paniculata, which shows great potential for becoming an alternative technique for industrial scale-up applications.

  19. Prediction and Optimization of Phase Transformation Region After Spot Continual Induction Hardening Process Using Response Surface Method

    Science.gov (United States)

    Qin, Xunpeng; Gao, Kai; Zhu, Zhenhua; Chen, Xuliang; Wang, Zhou

    2017-09-01

    The spot continual induction hardening (SCIH) process, which is a modified induction hardening, can be assembled to a five-axis cooperating computer numerical control machine tool to strengthen more than one small area or relatively large area on complicated component surface. In this study, a response surface method was presented to optimize phase transformation region after the SCIH process. The effects of five process parameters including feed velocity, input power, gap, curvature and flow rate on temperature, microstructure, microhardness and phase transformation geometry were investigated. Central composition design, a second-order response surface design, was employed to systematically estimate the empirical models of temperature and phase transformation geometry. The analysis results indicated that feed velocity has a dominant effect on the uniformity of microstructure and microhardness, domain size, oxidized track width, phase transformation width and height in the SCIH process while curvature has the largest effect on center temperature in the design space. The optimum operating conditions with 0.817, 0.845 and 0.773 of desirability values are expected to be able to minimize ratio (tempering region) and maximize phase transformation width for concave, flat and convex surface workpieces, respectively. The verification result indicated that the process parameters obtained by the model were reliable.

  20. RACLETTE: a model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Pt. I. Theory and description of model capabilities

    International Nuclear Information System (INIS)

    Raffray, A.R.; Federici, G.

    1997-01-01

    For pt.II see ibid., p.101-30, 1997. RACLETTE (Rate Analysis Code for pLasma Energy Transfer Transient Evaluation), a comprehensive but relatively simple and versatile model, was developed to help in the design analysis of plasma facing components (PFCs) under 'slow' high power transients, such as those associated with plasma vertical displacement events. The model includes all the key surface heat transfer processes such as evaporation, melting, and radiation, and their interaction with the PFC block thermal response and the coolant behaviour. This paper represents part I of two sister and complementary papers. It covers the model description, calibration and validation, and presents a number of parametric analyses shedding light on and identifying trends in the PFC armour block response to high plasma energy deposition transients. Parameters investigated include the plasma energy density and deposition time, the armour thickness and the presence of vapour shielding effects. Part II of the paper focuses on specific design analyses of ITER plasma facing components (divertor, limiter, primary first wall and baffle), including improvements in the thermal-hydraulic modeling required for better understanding the consequences of high energy deposition transients in particular for the ITER limiter case. (orig.)

  1. RACLETTE: a model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Part I: Theory and description of model capabilities

    Science.gov (United States)

    Raffray, A. René; Federici, Gianfranco

    1997-04-01

    RACLETTE (Rate Analysis Code for pLasma Energy Transfer Transient Evaluation), a comprehensive but relatively simple and versatile model, was developed to help in the design analysis of plasma facing components (PFCs) under 'slow' high power transients, such as those associated with plasma vertical displacement events. The model includes all the key surface heat transfer processes such as evaporation, melting, and radiation, and their interaction with the PFC block thermal response and the coolant behaviour. This paper represents part I of two sister and complementary papers. It covers the model description, calibration and validation, and presents a number of parametric analyses shedding light on and identifying trends in the PFC armour block response to high plasma energy deposition transients. Parameters investigated include the plasma energy density and deposition time, the armour thickness and the presence of vapour shielding effects. Part II of the paper focuses on specific design analyses of ITER plasma facing components (divertor, limiter, primary first wall and baffle), including improvements in the thermal-hydraulic modeling required for better understanding the consequences of high energy deposition transients in particular for the ITER limiter case.

  2. [Optimization of flash-type extraction technology of alisol B 23-acetate from Alismatis Rhizoma by response surface methodology].

    Science.gov (United States)

    Wei, Ying-Chun; Yan, Ming; Yang, Jing; Liu, Jun-Chao; Yin, Hong-Mei; Wu, Yun; Sun, Yong-Cheng; Xiao, Wei

    2016-02-01

    Response surface methodology was used to optimize and obtain the optimal flash-type extraction technology of alisol B 23-acetate from Alismatis Rhizoma. With the extraction rate of alisol B 23-acetate as an indicator, single-factor test was used to investigate the effect of ethanol volume fraction, liquid-solid ratio, extraction times and extracting time on the extraction rate of alisol B 23-acetate.The results were combined with Box-Benhnken design and response surface analysis to optimize the technology parameters for extraction process of Alismatis Rhizoma and obtain the optimal flash-type extraction technology under the following conditions: ethanol volume fraction 80%, liquid-solid ratio 12∶1, extraction 4 times, 114 s/time. Flash-type extraction technology of alisol B 23-acetate by response surface methodology is stable, time-saving, efficient, and with the advantages of room temperature extraction and no component damage, so it can be used for massive production. Copyright© by the Chinese Pharmaceutical Association.

  3. Environmentally responsive surface-modified silica nanoparticles for enhanced oil recovery

    International Nuclear Information System (INIS)

    Behzadi, Abed; Mohammadi, Aliasghar

    2016-01-01

    Environmentally responsive surface-modified nanoparticles are colloidal nanoparticles coated with, at least, two physicochemically distinct surface groups. Recent advances in the synthesis and production of nanoparticles have enabled the production of environmentally responsive surface-modified nanoparticles with both hydrophilic and hydrophobic surface groups. These nanoparticles act like colloidal surfactants. In this paper, environmentally responsive surface-modified silica nanoparticles are synthesized and used for enhancement of oil recovery. For this purpose, silica nanoparticles are coated with polyethylene glycol chains as hydrophilic agent and propyl chains as hydrophobic agent at various quantities, and their ability to modulate oil–water interface properties and oil recovery is examined. Oil–water interfacial tension and water surface tension are decreased by 50 % in the presence of silica nanoparticles coated with both agents. Measuring oil-drop contact angle on oil-wetted glass slides and carbonate rock sections, after aging in various surface-modified silica nanofluids, indicates that the wettability of various oil-wetted surfaces is modified from strongly oil-wet to water-wet. Flooding nanofluids to glass micro-models and pore-level investigations demonstrate that surface modification of silica nanoparticles, specially, with both hydrophilic and hydrophobic agents improves considerably their performance in increasing oil recovery and wettability alteration.

  4. Attenuating Immune Response of Macrophage by Enhancing Hydrophilicity of Ti Surface

    Directory of Open Access Journals (Sweden)

    Xiaohan Dai

    2015-01-01

    Full Text Available Immune responses can determine the in vivo fate of implanted materials. The strategy for developing implants has shifted towards using materials with immunomodulatory activity. However, the immunoregulatory effect of hydrophilicity of titanium surface on the macrophage behavior and its underlying mechanism remain poorly understood. Here, the Ti surface hydrophilicity-dependent behavior of murine RAW264.7 macrophages was investigated in vitro. Two laboratory models with significantly different surface hydrophilicity and similar roughness were established with Ti-polished and Ti-H2O2 surfaces. The results of cell morphology observation showed that the Ti-H2O2 surface yielded enhanced cell adhesion and less multinucleated cell formation. CCK-8 assay indicated that the growth rate of macrophage on Ti-H2O2 surface is higher than that of Ti-polished. ELISA assay result revealed lower level of proinflammatory factor TNF-α and higher level of anti-inflammatory factor IL-10 on the Ti-H2O2 surface compared to Ti-polished. Subsequently, immunofluorescence and western blotting analysis showed that activation of the NF-κB-TNF-α pathway might be involved in the modulation of the immune response by surface hydrophilicity. Together, these results suggested that relative high hydrophilic Ti surface might attenuate the immune response of macrophage by activating NF-κB signaling. These findings could provide new insights into designing implant devices for orthopedic applications.

  5. Environmentally responsive surface-modified silica nanoparticles for enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Behzadi, Abed; Mohammadi, Aliasghar, E-mail: amohammadi@sharif.edu [Sharif University of Technology, Department of Chemical and Petroleum Engineering (Iran, Islamic Republic of)

    2016-09-15

    Environmentally responsive surface-modified nanoparticles are colloidal nanoparticles coated with, at least, two physicochemically distinct surface groups. Recent advances in the synthesis and production of nanoparticles have enabled the production of environmentally responsive surface-modified nanoparticles with both hydrophilic and hydrophobic surface groups. These nanoparticles act like colloidal surfactants. In this paper, environmentally responsive surface-modified silica nanoparticles are synthesized and used for enhancement of oil recovery. For this purpose, silica nanoparticles are coated with polyethylene glycol chains as hydrophilic agent and propyl chains as hydrophobic agent at various quantities, and their ability to modulate oil–water interface properties and oil recovery is examined. Oil–water interfacial tension and water surface tension are decreased by 50 % in the presence of silica nanoparticles coated with both agents. Measuring oil-drop contact angle on oil-wetted glass slides and carbonate rock sections, after aging in various surface-modified silica nanofluids, indicates that the wettability of various oil-wetted surfaces is modified from strongly oil-wet to water-wet. Flooding nanofluids to glass micro-models and pore-level investigations demonstrate that surface modification of silica nanoparticles, specially, with both hydrophilic and hydrophobic agents improves considerably their performance in increasing oil recovery and wettability alteration.

  6. Environmentally responsive surface-modified silica nanoparticles for enhanced oil recovery

    Science.gov (United States)

    Behzadi, Abed; Mohammadi, Aliasghar

    2016-09-01

    Environmentally responsive surface-modified nanoparticles are colloidal nanoparticles coated with, at least, two physicochemically distinct surface groups. Recent advances in the synthesis and production of nanoparticles have enabled the production of environmentally responsive surface-modified nanoparticles with both hydrophilic and hydrophobic surface groups. These nanoparticles act like colloidal surfactants. In this paper, environmentally responsive surface-modified silica nanoparticles are synthesized and used for enhancement of oil recovery. For this purpose, silica nanoparticles are coated with polyethylene glycol chains as hydrophilic agent and propyl chains as hydrophobic agent at various quantities, and their ability to modulate oil-water interface properties and oil recovery is examined. Oil-water interfacial tension and water surface tension are decreased by 50 % in the presence of silica nanoparticles coated with both agents. Measuring oil-drop contact angle on oil-wetted glass slides and carbonate rock sections, after aging in various surface-modified silica nanofluids, indicates that the wettability of various oil-wetted surfaces is modified from strongly oil-wet to water-wet. Flooding nanofluids to glass micro-models and pore-level investigations demonstrate that surface modification of silica nanoparticles, specially, with both hydrophilic and hydrophobic agents improves considerably their performance in increasing oil recovery and wettability alteration.

  7. US-Japan workshop Q-181 on high heat flux components and plasma-surface interactions for next devices: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, R.T. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Yamashina, T. [ed.] [Hokkadio Univ. (Japan)

    1994-04-01

    This report contain viewgraphs of papers from the following sessions: plasma facing components issues for future machines; recent PMI results from several tokamaks; high heat flux technology; plasma facing components design and applications; plasma facing component materials and irradiation damage; boundary layer plasma; plasma disruptions; conditioning and tritium; and erosion/redeposition.

  8. US-Japan workshop Q-181 on high heat flux components and plasma-surface interactions for next devices: Proceedings

    International Nuclear Information System (INIS)

    McGrath, R.T.; Yamashina, T.

    1994-04-01

    This report contain viewgraphs of papers from the following sessions: plasma facing components issues for future machines; recent PMI results from several tokamaks; high heat flux technology; plasma facing components design and applications; plasma facing component materials and irradiation damage; boundary layer plasma; plasma disruptions; conditioning and tritium; and erosion/redeposition

  9. A novel pseudopodial component of the dendritic cell anti-fungal response: the fungipod.

    Directory of Open Access Journals (Sweden)

    Aaron K Neumann

    2010-02-01

    Full Text Available Fungal pathologies are seen in immunocompromised and healthy humans. C-type lectins expressed on immature dendritic cells (DC recognize fungi. We report a novel dorsal pseudopodial protrusion, the "fungipod", formed by DC after contact with yeast cell walls. These structures have a convoluted cell-proximal end and a smooth distal end. They persist for hours, exhibit noticeable growth and total 13.7+/-5.6 microm long and 1.8+/-0.67 microm wide at the contact. Fungipods contain clathrin and an actin core surrounded by a sheath of cortactin. The actin cytoskeleton, but not microtubules, is required for fungipod integrity and growth. An apparent rearward flow (225+/-55 nm/second exists from the zymosan contact site into the distal fungipod. The phagocytic receptor Dectin-1 is not required for fungipod formation, but CD206 (Mannose Receptor is the generative receptor for these protrusions. The human pathogen Candida parapsilosis induces DC fungipod formation strongly, but the response is species specific since the related fungal pathogens Candida tropicalis and Candida albicans induce very few and no fungipods, respectively. Our findings show that fungipods are dynamic actin-driven cellular structures involved in fungal recognition by DC. They may promote yeast particle phagocytosis by DC and are a specific response to large (i.e., 5 microm particulate ligands. Our work also highlights the importance of this novel protrusive structure to innate immune recognition of medically significant Candida yeasts in a species specific fashion.

  10. Phosphoproteomic dynamics of chickpea (Cicer arietinum L.) reveals shared and distinct components of dehydration response.

    Science.gov (United States)

    Subba, Pratigya; Barua, Pragya; Kumar, Rajiv; Datta, Asis; Soni, Kamlesh Kumar; Chakraborty, Subhra; Chakraborty, Niranjan

    2013-11-01

    Reversible protein phosphorylation is a ubiquitous regulatory mechanism that plays critical roles in transducing stress signals to bring about coordinated intracellular responses. To gain better understanding of dehydration response in plants, we have developed a differential phosphoproteome in a food legume, chickpea (Cicer arietinum L.). Three-week-old chickpea seedlings were subjected to progressive dehydration by withdrawing water, and the changes in the phosphorylation status of a large repertoire of proteins were monitored. The proteins were resolved by 2-DE and stained with phosphospecific fluorescent Pro-Q Diamond dye. Mass spectrometric analysis led to the identification of 91 putative phosphoproteins, presumably involved in a variety of functions including cell defense and rescue, photosynthesis and photorespiration, molecular chaperones, and ion transport, among others. Multiple sites of phosphorylation were predicted on several key elements, which include both the regulatory as well as the functional proteins. A critical survey of the phosphorylome revealed a DREPP (developmentally regulated plasma membrane protein) plasma membrane polypeptide family protein, henceforth designated CaDREPP1. The transcripts of CaDREPP1 were found to be differentially regulated under dehydration stress, further corroborating the proteomic results. This work provides new insights into the possible phosphorylation events triggered by the conditions of progressive water-deficit in plants.

  11. Conceptualizing psychological processes in response to globalization: Components, antecedents, and consequences of global orientations.

    Science.gov (United States)

    Chen, Sylvia Xiaohua; Lam, Ben C P; Hui, Bryant P H; Ng, Jacky C K; Mak, Winnie W S; Guan, Yanjun; Buchtel, Emma E; Tang, Willie C S; Lau, Victor C Y

    2016-02-01

    The influences of globalization have permeated various aspects of life in contemporary society, from technical innovations, economic development, and lifestyles, to communication patterns. The present research proposed a construct termed global orientation to denote individual differences in the psychological processes of acculturating to the globalizing world. It encompasses multicultural acquisition as a proactive response and ethnic protection as a defensive response to globalization. Ten studies examined the applicability of global orientations among majority and minority groups, including immigrants and sojourners, in multicultural and relatively monocultural contexts, and across Eastern and Western cultures. Multicultural acquisition is positively correlated with both independent and interdependent self-construals, bilingual proficiency and usage, and dual cultural identifications. Multicultural acquisition is promotion-focused, while ethnic protection is prevention-focused and related to acculturative stress. Global orientations affect individuating and modest behavior over and above multicultural ideology, predict overlap with outgroups over and above political orientation, and predict psychological adaptation, sociocultural competence, tolerance, and attitudes toward ethnocultural groups over and above acculturation expectations/strategies. Global orientations also predict English and Chinese oral presentation performance in multilevel analyses and the frequency and pleasantness of intercultural contact in cross-lagged panel models. We discuss how the psychological study of global orientations contributes to theory and research on acculturation, cultural identity, and intergroup relations. (c) 2016 APA, all rights reserved).

  12. Main Leaf Polyphenolic Components of Berry Color Variant Grapevines and Their Acclimative Responses to Sunlight Exposure

    Directory of Open Access Journals (Sweden)

    Marianna Kocsis

    2015-12-01

    Full Text Available Grapevine leaf synthesizes a wide variety of bioactive secondary metabolites, including polyphenols, which are also key components in ensuring development and growth of the whole plant even under adverse environmental conditions. Our study evaluates the nonanthocyanin polyphenolic composition in grapevine leaves of three varieties of Gohér conculta (Vitis vinifera L. native to Hungary. A high performance liquid chromatography (HPLC system including a diode array detector (DAD coupled to a time-of-flight mass spectrometer (q-TOFMS was successfully applied to profile intact glycoconjugate forms in samples. In-source fragmentation was utilized in order to provide structural information on the compounds. Using this method, the presence of 16 polyphenolic metabolites were confirmed, and eight of them were subjected to further quantification in sun acclimated and half shaded leaves. Intracellular microimaging detected accumulation of flavonols in cell nuclei, cell wall and chloroplasts. Our findings demonstrated that Gohér conculta—a special grapevine taxon of our viticultural heritage with berry color variants—is a suitable model to study the interaction between genetic and environmental factors in determination of grapevine phenolic composition.

  13. Dietary Aloe vera components' effects on cholesterol lowering and estrogenic responses in juvenile goldfish, Carassius auratus.

    Science.gov (United States)

    Palermo, Francesco A; Cocci, Paolo; Angeletti, Mauro; Felici, Alberto; Polzonetti-Magni, Alberta Maria; Mosconi, Gilberto

    2013-08-01

    Aloes are now considered a very interesting source of bioactive compounds among which phytosterols should play a major role. The present study is an attempt to investigate the hypocholesterolemic activity of Aloe vera associated with its impact on the reproductive status of juvenile goldfish. Therefore, the short- and long-term effects of feeding supplementary diet containing aloe components (20 mg aloe/g diet; 2%) on plasma lipids, plasma vitellogenin, and hepatic estrogen receptor α/β1 mRNA levels in goldfish were examined. Results of GC-MS for phytosterols show high abundance of β-sitosterol in freeze-dried powder of Aloe vera whole leaves. Moreover, a 2% aloe powder dietary supplement was not found estrogenic in juvenile goldfish after either 7- or 30-day treatment, but was consistent in plasma hypocholesterolemic effects following long-term exposure. The present data further support that plasma cholesterol modulation induced by phytosterols may not be related to estrogen-like activity.

  14. Mechanisms of recurrent otitis media: importance of the immune response to bacterial surface antigens.

    Science.gov (United States)

    Murphy, T F; Yi, K

    1997-12-29

    Otitis-prone children experience recurrent episodes of otitis media due to nontypeable H. influenzae (NTHI). A protective immune response occurs following infection, but this immune response is specific for the infecting strain, leaving the child susceptible to infection by other strains of NTHI. Little is known about the mechanism by which a strain-specific antibody response occurs to nonencapsulated bacteria. To explore the mechanism by which this strain-specific response occurs, animals were inoculated with whole bacterial cells and the antibody response was studied. The antibody response was predominantly directed to a highly strain-specific, immunodominant surface loop on the major outer membrane protein. This exquisitely restricted immune response leaves the host susceptible to recurrent infections by many strains of NTHI. The ability of the bacterium to direct the host to make a strain-specific antibody response has important implications in understanding the immune response to otitis media due to NTHI and in designing strategies for vaccine development.

  15. Electromechanical response of a curved piezoelectric nanobeam with the consideration of surface effects

    International Nuclear Information System (INIS)

    Yan Zhi; Jiang Liying

    2011-01-01

    This work investigates the electromechanical response of a curved piezoelectric nanobeam with the consideration of surface effects through the surface-layer-based model and the generalized Young-Laplace equations. For nanoscale piezoelectric structures, the surface effects also include surface piezoelectricity in addition to the residual surface stress and surface elasticity for elastic nanomaterials. A Euler-Bernoulli curved beam theory is used to get the explicit solutions for the electroelastic fields of a curved cantilever beam when subjected to mechanical and electrical loads. In order to apply the appropriate boundary conditions on the beam, effective axial force, shear force and moment are derived. The results indicate that the surface effects play a significant role in the electroelastic fields and the piezoelectric response of the curved piezoelectric nanobeam. It is also found that the coupling of the residual surface stress, the surface elasticity and the surface piezoelectricity may be dramatic despite that the influence of the individual one is small under some circumstances. This study is expected to be useful for design and applications of curved beam based piezoelectric nanodevices, such as the curved nanowires/nanobelts or nanorings as nanoswitches or nanoactuators for displacement control purpose.

  16. Macrobenthic species response surfaces along estuarine gradients: prediction by logistic regression

    NARCIS (Netherlands)

    Ysebaert, T.; Meire, P.; Herman, P.M.J.; Verbeek, H.

    2002-01-01

    This study aims at contributing to the development of statistical models to predict macrobenthic species response to environmental conditions in estuarine ecosystems. Ecological response surfaces are derived for 10 estuarine macrobenthic species. Logistic regression is applied on a large data set,

  17. Interaction between Nitrous Oxide, Sevoflurane, and Opioids A Response Surface Approach

    NARCIS (Netherlands)

    Vereecke, Hugo E. M.; Proost, Johannes H.; Heyse, Bjorn; Eleveld, Douglas J.; Katoh, Takasumi; Luginbuehl, Martin; Struys, Michel M. R. F.

    Background: The interaction of sevoflurane and opioids can be described by response surface modeling using the hierarchical model. We expanded this for combined administration of sevoflurane, opioids, and 66 vol.% nitrous oxide (N2O), using historical data on the motor and hemodynamic responsiveness

  18. Surface chemistry of Ti6Al4V components fabricated using selective laser melting for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Vaithilingam, Jayasheelan, E-mail: Jayasheelan.Vaithilingam@nottingham.ac.uk [Additive Manufacturing and 3D Printing Research Group, EPSRC Centre for Innovative Manufacturing in Additive Manufacturing, School of Engineering, The University of Nottingham, Nottingham NG7 2RD (United Kingdom); Prina, Elisabetta [School of Pharmacy, Centre for Biomolecular Sciences, The University of Nottingham, Nottingham NG7 2RD (United Kingdom); Goodridge, Ruth D.; Hague, Richard J.M. [Additive Manufacturing and 3D Printing Research Group, EPSRC Centre for Innovative Manufacturing in Additive Manufacturing, School of Engineering, The University of Nottingham, Nottingham NG7 2RD (United Kingdom); Edmondson, Steve [School of Materials, The University of Manchester, Manchester M13 9PL (United Kingdom); Rose, Felicity R.A.J. [School of Pharmacy, Centre for Biomolecular Sciences, The University of Nottingham, Nottingham NG7 2RD (United Kingdom); Christie, Steven D.R. [Department of Chemistry, Loughborough University, Loughborough LE11 3TU (United Kingdom)

    2016-10-01

    Selective laser melting (SLM) has previously been shown to be a viable method for fabricating biomedical implants; however, the surface chemistry of SLM fabricated parts is poorly understood. In this study, X-ray photoelectron spectroscopy (XPS) was used to determine the surface chemistries of (a) SLM as-fabricated (SLM-AF) Ti6Al4V and (b) SLM fabricated and mechanically polished (SLM-MP) Ti6Al4V samples and compared with (c) traditionally manufactured (forged) and mechanically polished Ti6Al4V samples. The SLM–AF surface was observed to be porous with an average surface roughness (Ra) of 17.6 ± 3.7 μm. The surface chemistry of the SLM-AF was significantly different to the FGD-MP surface with respect to elemental distribution and their existence on the outermost surface. Sintered particles on the SLM-AF surface were observed to affect depth profiling of the sample due to a shadowing effect during argon ion sputtering. Surface heterogeneity was observed for all three surfaces; however, vanadium was witnessed only on the mechanically polished (SLM-MP and FGD-MP) surfaces. The direct and indirect 3T3 cell cytotoxicity studies revealed that the cells were viable on the SLM fabricated Ti6Al4V parts. The varied surface chemistry of the SLM-AF and SLM-MP did not influence the cell behaviour. - Highlights: • Surface chemistry of selective laser melted (SLM) Ti6Al4V parts was compared with conventionally forged Ti6Al4V parts. • The surface elemental compositions of the SLM as-fabricated surfaces were significantly different to the forged surface. • Surface oxide-layer of the SLM as-fabricated was thicker than the polished SLM surfaces and the forged Ti6Al4V surfaces.

  19. Vulnerability and behavioral response to ultraviolet radiation in the components of a foliar mite prey-predator system

    Science.gov (United States)

    Tachi, Fuyuki; Osakabe, Masahiro

    2012-12-01

    Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites ( Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite ( Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species ( T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.

  20. Biosorption of diethyl phthalate ester by living and nonliving Burkholderia cepacia and the role of its cell surface components.

    Science.gov (United States)

    Luo, Si; Li, Langlang; Chen, Anwei; Zeng, Qingru; Xia, Hao; Gu, Ji-Dong

    2017-07-01

    In this study, the dibutyl phthalate (DBP) binding properties of a DBP-tolerant bacterium (B. cepacia) were characterized in terms of adsorption kinetics and isotherm. Living and nonliving cells both exhibited rapid removal of DBP, achieving more than 80% of maximum sorption within 30 min of contact and reached the equilibrium after 3 h. The adsorption isotherms were well fitted with the Sips model and the nonliving cells have greater biosorption capacity and affinity for DBP than the living cells. Furthermore, the absence of an active mechanism dependent on metabolism implied that the DBP bioaccumulation by living cells was mainly attribute to passive surface binding. The optimum pH for DBP adsorption by living and nonliving cells were both observed to be 6.0. The biosorptive mechanism of DBP binding by B. cepacia was further confirmed by FTIR analysis and various chemical treatments. FTIR results indicated that the phosphate and CH 2 groups on B. cepacia were the main bounding sites for DBP. Furthermore, 2.28, 2.15, 1.93 and 0.87 g of pretreated cells were obtained from 2.40 g of native cells via extracellular polymeric substances (EPS), superficial layer-capsule, lipids components and cell membrane removal treatments, respectively. Total binding amount of DBP on the native cells, EPS-removed cells, capsule-removed cells, lipids-extracted cells and membrane-removed cells were 26.69, 24.84, 24.93, 16.11 and 10.80 mg, respectively, suggesting that the cell wall lipids, proteins or peptidoglycan might play important roles in the sorption of DBP by B. cepacia. The information could be applied in understanding on the mobility, transport and ultimate fate of PAEs in soil and related environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Modification of titanium alloys surface properties by plasma electrolytic oxidation (PEO) and influence on biological response.

    Science.gov (United States)

    Echeverry-Rendón, Mónica; Galvis, Oscar; Aguirre, Robinson; Robledo, Sara; Castaño, Juan Guillermo; Echeverría, Félix

    2017-09-27

    Surface characteristics can mediate biological interaction improving or affecting the tissue integration after implantation of a biomaterial. Features such as topography, wettability, surface energy and chemistry can be key determinants for interactions between cells and materials. Plasma electrolytic oxidation (PEO) is a technique used to control this kind of parameters by the addition of chemical species and the production of different morphologies on the surfaces of titanium and its alloys. With the purpose to improve the biological response, surfaces of c.p titanium and Ti6Al4V were modified by using PEO. Different electrolytes, voltages, current densities and anodizing times were tested in order to obtain surfaces with different characteristics. The obtained materials were characterized by different techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and glow discharge optical emission spectroscopy (GDOES). Wettability of the obtained surfaces were measured and the corresponding surface energies were calculated. Superhydrophilic surfaces with contact angles of about 0 degrees were obtained without any other treatment but PEO and this condition in some cases remains stable after several weeks of anodizing; crystal phase composition (anatase-rutile) of the anodic surface appears to be critical for obtaining this property. Finally, in order to verify the biological effect of these surfaces, osteoblast were seeded on the samples. It was found that cell behavior improves as SFE (surface free energy) and coating porosity increases whereas it is affected negatively by roughness. Techniques for surface modification allow changes in the coatings such as surface energy, roughness and porosity. As a consequence of this, biological response can be altered. In this paper, surfaces of c.p Ti and Ti6Al4V were modified by using plasma electrolytic oxidation (PEO) in order to accelerate the cell adhesion process.

  2. Visible tumor surface response to physical plasma and apoptotic cell kill in head and neck cancer.

    Science.gov (United States)

    Schuster, Matthias; Seebauer, Christian; Rutkowski, Rico; Hauschild, Anna; Podmelle, Fred; Metelmann, Camilla; Metelmann, Bibiana; von Woedtke, Thomas; Hasse, Sybille; Weltmann, Klaus-Dieter; Metelmann, Hans-Robert

    2016-09-01

    The aim of the study was to learn, whether clinical application of cold atmospheric pressure plasma (CAP) is able to cause (i) visible tumor surface effects and (ii) apoptotic cell kill in squamous cell carcinoma and (iii) whether CAP-induced visible tumor surface response occurs as often as CAP-induced apoptotic cell kill. Twelve patients with advanced head and neck cancer and infected ulcerations received locally CAP followed by palliative treatment. Four of them revealed tumor surface response appearing 2 weeks after intervention. The tumor surface response expressed as a flat area with vascular stimulation (type 1) or a contraction of tumor ulceration rims forming recesses covered with scabs, in each case surrounded by tumor tissue in visible progress (type 2). In parallel, 9 patients with the same kind of cancer received CAP before radical tumor resection. Tissue specimens were analyzed for apoptotic cells. Apoptotic cells were detectable and occurred more frequently in tissue areas previously treated with CAP than in untreated areas. Bringing together both findings and placing side by side the frequency of clinical tumor surface response and the frequency of analytically proven apoptotic cell kill, detection of apoptotic cells is as common as clinical tumor surface response. There was no patient showing signs of an enhanced or stimulated tumor growth under influence of CAP. CAP was made applicable by a plasma jet, kINPen(®) MED (neoplas tools GmbH, Greifswald, Germany). Copyright © 2016. Published by Elsevier Ltd.

  3. Catalog of physical protection equipment. Book 3: Volume VI. Automated response components

    International Nuclear Information System (INIS)

    Haberman, W.

    1977-06-01

    The Catalog of Physical Protection Equipment presents information on currently available physical protection equipment that could be employed to safeguard special nuclear materials. The primary source of information was the responses of manufacturers and vendors to requests for literature and data. All equipment listed in the Catalog has been screened in accordance with the following general criteria, and only items meeting one or more of these criteria have been included: (1) equipment is commercially available off-the-shelf; (2) equipment is currently in use at commercial nuclear facilities licensed or to be licensed by NRC; (3) equipment is applicable for use at nuclear facilities licensed or to be licensed by NRC; (4) equipment can operate in the environmental conditions present at nuclear facilities; and (5) equipment is not designed solely or primarily for residential use. The final report describes the methodology and rationale used to create the Catalog of Physical Protection Equipment

  4. Bacterial fumarase and L-malic acid are evolutionary ancient components of the DNA damage response

    Science.gov (United States)

    Singer, Esti; Silas, Yardena BH; Ben-Yehuda, Sigal

    2017-01-01

    Fumarase is distributed between two compartments of the eukaryotic cell. The enzyme catalyses the reversible conversion of fumaric to L-malic acid in mitochondria as part of the tricarboxylic acid (TCA) cycle, and in the cytosol/nucleus as part of the DNA damage response (DDR). Here, we show that fumarase of the model prokaryote Bacillus subtilis (Fum-bc) is induced upon DNA damage, co-localized with the bacterial DNA and is required for the DDR. Fum-bc can substitute for both eukaryotic functions in yeast. Furthermore, we found that the fumarase-dependent intracellular signaling of the B. subtilis DDR is achieved via production of L-malic acid, which affects the translation of RecN, the first protein recruited to DNA damage sites. This study provides a different evolutionary scenario in which the dual function of the ancient prokaryotic fumarase, led to its subsequent distribution into different cellular compartments in eukaryotes. PMID:29140245

  5. Environmental components of OCS policy committee recommendations regarding national oil spill prevention and response program

    International Nuclear Information System (INIS)

    Groat, C.G.; Thorman, J.

    1991-01-01

    The Exxon Valdez oil spill of March 24, 1989 resulted in thousands of pages of analytical reports assessing the environmental, organizational, legal, procedural, social, economic, and political aspects of the event. Even though the accident was a transportation incident, it had a major impact on the public and political perception of offshore oil operations. This caused the OCS Policy Committee, which advises the Secretary of the Interior and the Minerals Management Service on Outer Continental Shelf resource development and environmental matters, to undertake a review of the reports for the purpose of developing recommendations to the secretary for improvements in OCS operations that would insure maximum efforts to prevent spills and optimal ability to deal with any that occur. The Committee felt strongly that 'a credible national spill prevention and response program from both OCS and non-OCS oil spills in the marine environment is needed to create the political climate for a viable OCS program.' The report of the Committee described eight essential elements of this program; four of these focused on the environmental aspects of oil spills, calling for (1) adequate characterization of the marine and coastal environment, including both information and analysis, accessible to decision makers, (2) the capacity to restore economic and environmental resources as quickly as possible if damage occurs, (3) a mechanism for research on oil spill impacts, and (4) a meaningful role for all interested and responsible parties, including the public, in as many of these activities as possible, from spill prevention and contingency planning to environmental oversight of ongoing operations and participation in clean-up and restoration activities

  6. Green's function surface-integral method for nonlocal response of plasmonic nanowires in arbitrary dielectric environments

    DEFF Research Database (Denmark)

    Yan, Wei; Mortensen, N. Asger; Wubs, Martijn

    2013-01-01

    We develop a nonlocal-response generalization to the Green's function surface-integral method (GSIM), also known as the boundary-element method. This numerically efficient method can accurately describe the linear hydrodynamic nonlocal response of arbitrarily shaped plasmonic nanowires in arbitrary...... and the longitudinal wave number become smaller, or when the effective background permittivity or the mode inhomogeneity increase. The inhomogeneity can be expressed in terms of an effective angular momentum of the surface-plasmon mode. We compare local and nonlocal response of freestanding nanowires, and of nanowires...

  7. Near 7-day response of ocean bottom pressure to atmospheric surface pressure and winds in the northern South China Sea

    Science.gov (United States)

    Zhang, Kun; Zhu, Xiao-Hua; Zhao, Ruixiang

    2018-02-01

    Ocean bottom pressures, observed by five pressure-recording inverted echo sounders (PIESs) from October 2012 to July 2014, exhibit strong near 7-day variability in the northern South China Sea (SCS) where long-term in situ bottom pressure observations are quite sparse. This variability was strongest in October 2013 during the near two years observation period. By joint analysis with European Center for Medium-Range Weather Forecasts (ECMWF) data, it is shown that the near 7-day ocean bottom pressure variability is closely related to the local atmospheric surface pressure and winds. Within a period band near 7 days, there are high coherences, exceeding 95% significance level, of observed ocean bottom pressure with local atmospheric surface pressure and with both zonal and meridional components of the wind. Ekman pumping/suction caused by the meridional component of the wind in particular, is suggested as one driving mechanism. A Kelvin wave response to the near 7-day oscillation would propagate down along the continental slope, observed at the Qui Nhon in the Vietnam. By multiple and partial coherence analyses, we find that local atmospheric surface pressure and Ekman pumping/suction show nearly equal influence on ocean bottom pressure variability at near 7-day periods. A schematic diagram representing an idealized model gives us a possible mechanism to explain the relationship between ocean bottom pressure and local atmospheric forcing at near 7-day periods in the northern SCS.

  8. Surface tension of different sized single-component droplets, according to macroscopic data obtained using the lattice gas model and the critical droplet size during phase formation

    Science.gov (United States)

    Tovbin, Yu. K.; Zaitseva, E. S.; Rabinovich, A. B.

    2017-10-01

    Size dependences of the surface tension of spherical single-component droplets are calculated using equations of the lattice gas model for 19 compounds. Parameters of the model are found from experimental data on the surface tension of these compounds for a macroscopic planar surface. The chosen low-molecular compounds satisfy the law of corresponding states. To improve agreement with the experimental data, Lennard-Jones potential parameters are varied within 10% deviations. The surface tensions of different sized equilibrium droplets are calculated at elevated and lowered temperatures. It is found that the surface tension of droplets grows monotonically as the droplet size increases from zero to its bulk value. The droplet size R 0 corresponding to zero surface tension corresponds to the critical size of the emergence of a new phase. The critical droplet sizes in the new phase of the considered compounds are estimated for the first time.

  9. Multi-response optimization of T300/epoxy prepreg tape-wound cylinder by grey relational analysis coupled with the response surface method

    Science.gov (United States)

    Kang, Chao; Shi, Yaoyao; He, Xiaodong; Yu, Tao; Deng, Bo; Zhang, Hongji; Sun, Pengcheng; Zhang, Wenbin

    2017-09-01

    This study investigates the multi-objective optimization of quality characteristics for a T300/epoxy prepreg tape-wound cylinder. The method integrates the Taguchi method, grey relational analysis (GRA) and response surface methodology, and is adopted to improve tensile strength and reduce residual stress. In the winding process, the main process parameters involving winding tension, pressure, temperature and speed are selected to evaluate the parametric influences on tensile strength and residual stress. Experiments are conducted using the Box-Behnken design. Based on principal component analysis, the grey relational grades are properly established to convert multi-responses into an individual objective problem. Then the response surface method is used to build a second-order model of grey relational grade and predict the optimum parameters. The predictive accuracy of the developed model is proved by two test experiments with a low prediction error of less than 7%. The following process parameters, namely winding tension 124.29 N, pressure 2000 N, temperature 40 °C and speed 10.65 rpm, have the highest grey relational grade and give better quality characteristics in terms of tensile strength and residual stress. The confirmation experiment shows that better results are obtained with GRA improved by the proposed method than with ordinary GRA. The proposed method is proved to be feasible and can be applied to optimize the multi-objective problem in the filament winding process.

  10. Tomography-Based Quantification of Regional Differences in Cortical Bone Surface Remodeling and Mechano-Response.

    Science.gov (United States)

    Birkhold, Annette I; Razi, Hajar; Duda, Georg N; Checa, Sara; Willie, Bettina M

    2017-03-01

    Bone has an adaptive capacity to maintain structural integrity. However, there seems to be a heterogeneous cortical (re)modeling response to loading at different regions within the same bone, which may lead to inconsistent findings since most studies analyze only one region. It remains unclear if the local mechanical environment is responsible for this heterogeneous response and whether both formation and resorption are affected. Thus, we compared the formation and resorptive response to in vivo loading and the strain environment at two commonly analyzed regions in the mouse tibia, the mid-diaphysis and proximal metaphysis. We quantified cortical surface (re)modeling by tracking changes between geometrically aligned consecutive in vivo micro-tomography images (time lapse 15 days). We investigated the local mechanical strain environment using finite element analyses. The relationship between mechanical stimuli and surface (re)modeling was examined by sub-dividing the mid-diaphysis and proximal metaphysis into 32 sub-regions. In response to loading, metaphyseal cortical bone (re)modeled predominantly at the periosteal surface, whereas diaphyseal (re)modeling was more pronounced at the endocortical surface. Furthermore, different set points and slopes of the relationship between engendered strains and remodeling response were found for the endosteal and periosteal surfaces at the metaphyseal and diaphyseal regions. Resorption was correlated with strain at the endocortical, but not the periosteal surfaces, whereas, formation correlated with strain at all surfaces, except at the metaphyseal periosteal surface. Therefore, besides mechanical stimuli, other non-mechanical factors are likely driving regional differences in adaptation. Studies investigating adaptation to loading or other treatments should consider region-specific (re)modeling differences.

  11. Effect of surface loading on the hydro-mechanical response of a tunnel in saturated ground

    Directory of Open Access Journals (Sweden)

    Simon Heru Prassetyo

    2016-09-01

    Full Text Available The design of underground spaces in urban areas must account not only for the current overburden load but also for future surface loads, such as from construction of high-rise buildings above underground structures. In saturated ground, the surface load will generate an additional mechanical response through stress changes and ground displacement, as well as a hydraulic response through pore pressure changes. These hydro-mechanical (H-M changes can severely influence tunnel stability. This paper examines the effect of surface loading on the H-M response of a typical horseshoe-shaped tunnel in saturated ground. Two tunnel models were created in the computer code Fast Lagrangian Analysis of Continua (FLAC. One model represented weak and low permeability ground (stiff clay, and the other represented strong and high permeability ground (weathered granite. Each of the models was run under two liner permeabilities: permeable and impermeable. Two main cases were compared. In Case 1, the surface load was applied 10 years after tunnel construction. In Case 2, the surface load was applied after the steady state pore pressure condition was achieved. The simulation results show that tunnels with impermeable liners experienced the most severe influence from the surface loading, with high pore pressures, large inward displacement around the tunnels, and high bending moments in the liner. In addition, the severity of the response increased toward steady state. This induced H-M response was worse for tunnels in clay than for those in granite. Furthermore, the long-term liner stabilities in Case 1 and Case 2 were similar, indicating that the influence of the length of time between when the tunnel was completed and when the surface load was applied was negligible. These findings suggest that under surface loading, in addition to the ground strength, tunnel stability in saturated ground is largely influenced by liner permeability and the long-term H-M response of

  12. Inflammatory response to titanium surfaces with fibrinogen and catalase coatings: an in vitro study.

    Science.gov (United States)

    Göransson, A; Gretzer, C; Tengvall, P; Wennerberg, A

    2007-03-01

    The aim of the present study was to evaluate the possibility to modulate the early inflammatory response in vitro by coating titanium surfaces with candidate proinflammatory (fibrinogen coated turned titanium "Fib") and antiinflammatory proteins (catalase on top of fibrinogen coated turned titanium "Cat"). Additionally, turned titanium surfaces (Ti) were used as controls. The discs were incubated with human mononuclear cells. Adhered cells were investigated with respect to number, viability, differentiation (acute marker 27E10 vs. chronic marker RM3/1), and cytokine production (TNF-alpha and IL-10), after 24 and 72 h. The results indicated that it is possible to modulate the inflammatory response with protein coatings. However, the strongest inflammatory response, indicated by increased number of adhered cells and release of pro and antiinflammatory mediators, was induced by Cat. Furthermore, the cytokine production on this surface was not sensitive to LPS stimulation. Differentiation measured as the expression of the chronic cell surface marker, dominated after 72 h for all surface modifications and Cat displayed an increased number compared to the others. A decrease in the total number of adhered cells and amounts of TNF-alpha were observed on all surfaces over time. The cell viability was, in general, high for all tested surfaces. In conclusion, the study proved it possible to influence the early inflammatory response in vitro by immobilizing protein coatings to titanium surfaces. However, the catalase surface demonstrated the strongest inflammatory response, and the possibility to selectively use the potent antiinflammatory capacity of catalase needs to be further evaluated.

  13. The transient response for different types of erodable surface thermocouples using finite element analysis

    Directory of Open Access Journals (Sweden)

    Mohammed Hussein

    2007-01-01

    Full Text Available The transient response of erodable surface thermocouples has been numerically assessed by using a two dimensional finite element analysis. Four types of base metal erodable surface thermocouples have been examined in this study, included type-K (alumel-chromel, type-E (chromel-constantan, type-T (copper-constantan, and type-J (iron-constantan with 50 mm thick- ness for each. The practical importance of these types of thermocouples is to be used in internal combustion engine studies and aerodynamics experiments. The step heat flux was applied at the surface of the thermocouple model. The heat flux from the measurements of the surface temperature can be commonly identified by assuming that the heat transfer within these devices is one-dimensional. The surface temperature histories at different positions along the thermocouple are presented. The normalized surface temperature histories at the center of the thermocouple for different types at different response time are also depicted. The thermocouple response to different heat flux variations were considered by using a square heat flux with 2 ms width, a sinusoidal surface heat flux variation width 10 ms period and repeated heat flux variation with 2 ms width. The present results demonstrate that the two dimensional transient heat conduction effects have a significant influence on the surface temperature history measurements made with these devices. It was observed that the surface temperature history and the transient response for thermocouple type-E are higher than that for other types due to the thermal properties of this thermocouple. It was concluded that the thermal properties of the surrounding material do have an impact, but the properties of the thermocouple and the insulation materials also make an important contribution to the net response.

  14. Application of response surface methodology to tailor the surface chemistry of electrospun chitosan-poly(ethylene oxide) fibers.

    Science.gov (United States)

    Bösiger, Peter; Richard, Isabelle M T; Le Gat, Luce; Michen, Benjamin; Schubert, Mark; Rossi, René M; Fortunato, Giuseppino

    2018-04-15

    Chitosan is a promising biocompatible polymer for regenerative engineering applications, but its processing remains challenging due to limited solubility and rigid crystalline structure. This work represents the development of electrospun chitosan/poly(ethylene oxide) blend nanofibrous membranes by means of a numerical analysis in order to identify and tailor the main influencing parameters with respect to accessible surface nitrogen functionalities which are of importance for the biological activity as well as for further functionalization. Depending on the solution composition, both gradient fibers and homogenous blended fiber structures could be obtained with surface nitrogen concentrations varying between 0 and 6.4%. Response surface methodology (RSM) revealed chitosan/poly(ethylene oxide) ratio and chitosan molecular weight as the main influencing factors with respect to accessible nitrogen surface atoms and respective concentrations. The model showed good adequacy hence providing a tool to tailor the surface properties of chitosan/poly(ethylene oxide) blends by addressing the amount of accessible chitosan. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Robust Optimization Design for Turbine Blade-Tip Radial Running Clearance using Hierarchically Response Surface Method

    Science.gov (United States)

    Zhiying, Chen; Ping, Zhou

    2017-11-01

    Considering the robust optimization computational precision and efficiency for complex mechanical assembly relationship like turbine blade-tip radial running clearance, a hierarchically response surface robust optimization algorithm is proposed. The distribute collaborative response surface method is used to generate assembly system level approximation model of overall parameters and blade-tip clearance, and then a set samples of design parameters and objective response mean and/or standard deviation is generated by using system approximation model and design of experiment method. Finally, a new response surface approximation model is constructed by using those samples, and this approximation model is used for robust optimization process. The analyses results demonstrate the proposed method can dramatic reduce the computational cost and ensure the computational precision. The presented research offers an effective way for the robust optimization design of turbine blade-tip radial running clearance.

  16. Assessing the effect of 5-hydroxymethylfurfural on selected components of immune responses in mice immunised with ovalbumin.

    Science.gov (United States)

    Alizadeh, Mohammad; Khodaei, Hamed; Mesgari Abbasi, Mehran; Saleh-Ghadimi, Sevda

    2017-09-01

    5-Hydroxymethylfurfural (5-HMF) is one of the most important products of the Maillard reaction. In recent years, many profitable biological effects of this compound have been demonstrated. This study sought to elucidate the anti-allergic effect of 5-HMF by investigating some selected components of the immune response in BALB/c mice immunised with ovalbumin (OVA). Immunised animals had an increased level of serum total and OVA-specific antibodies when compared to the control (P mice. 5-HMF could therefore be a novel therapeutic approach for the prevention of IgE-mediated allergic diseases. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  17. Link between chemotactic response to Ni2+ and its adsorption onto the Escherichia coli cell surface.

    Science.gov (United States)

    Borrok, David; Borrok, M Jack; Fein, Jeremy B; Kiessling, Laura L

    2005-07-15

    Bacterial chemotaxis is of medical, biological, and geological significance. Despite its importance, current chemotaxis measurements fail to account for the speciation of the chemical effector and the protonation state of the bacterial surface. We hypothesize that adsorption of Ni2+ onto the surface of Escherichia coli can influence its effective concentration and therefore influence its ability to induce a repellent response. By measuring repellent response at different pH values, the influence of Ni2+ adsorption on chemotaxis was assessed. In addition, we tested the effect of different Ni2+ chelating agents. Our data indicate that adsorption reactions influence the chemotactic response to Ni2+. We use potentiometric titration and Ni2+ adsorption experiments to develop and constrain a thermodynamic model capable of quantifying the concentration of Ni2+ at the bacteria/solution interface. Results from this model predict that the concentration of adsorbed Ni2+ is linearly proportional to the magnitude of the chemotactic response in E. coli. If adsorption is linked to chemotaxis in other cases, then chemotactic responses in realistic settings depend on a number of environmental factors such as pH, competing binding agents (e.g., aqueous organic acids, natural organic matter, mineral surfaces, etc.), and ionic strength. Our modeling approach quantifies adsorbed species on bacterial surfaces and may be used to predict the responses of different species to a variety of chemoeffectors. Our data suggest that specified changes in environmental conditions can be used to tune chemotactic responses in natural biological and geological settings.

  18. The genetic component of the forced diving bradycardia response in mammals

    Directory of Open Access Journals (Sweden)

    Andreas eFahlman

    2011-09-01

    Full Text Available We contrasted the forced diving bradycardia between two genetically similar (inbred rat strains (Fischer and Buffalo, compared to that of outbred rats (Wistar. The animals were habituated to forced diving for 4 weeks. Each animal was then tested during one 40-sec dive on each of 3 days. The heart rate (fH was measured before, during, and after each dive. Fischer and Buffalo exhibited marked difference in dive bradycardia (Fischer: 120.9 ± 14.0 beats • min-1 vs. Buffalo: 92.8 ± 12.8 beats • min-1, P < 0.05. Outbred rats showed an intermediate response (103.0 ± 30.9 beats • min-1 but their between-animal variability in mean dive fH and pre-diving resting fH were higher than the inbred strains (P < 0.05, which showed no difference (P > 0.05. The decreased variability in fH in inbred rats as compared with the outbred group indicates that reduced genetic variability minimizes variability of the diving bradycardia between individuals. Heritability within strains was assessed by the repeatability (R index and was 0.93 ± 0.05 for the outbred, 0.84 ± 0.16 for Buffalo, and 0.80 ± 0.12 for Fischer rats for fH during diving. Our results suggest that a portion of the mammalian diving bradycardia may be a heritable trait.

  19. Effects of playing surface on physiological responses and performance variables in a controlled football simulation.

    Science.gov (United States)

    Hughes, Michael G; Birdsey, Laurence; Meyers, Rob; Newcombe, Daniel; Oliver, Jon Lee; Smith, Paul M; Stembridge, Michael; Stone, Keeron; Kerwin, David George

    2013-01-01

    In spite of the increased acceptance of artificial turf in football, few studies have investigated if matches are altered by the type of surface used and no research has compared physiological responses to football activity on artificial and natural surfaces. In the present study, participants performed a football match simulation on high-quality artificial and natural surfaces. Neither mean heart rate (171 ± 9 beats · min(-1) vs. 171 ± 9 beats · min(-1); P > 0.05) nor blood lactate (4.8 ± 1.6 mM vs. 5.3 ± 1.8 mM; P > 0.05) differed between the artificial and natural surface, respectively. Measures of sprint, jumping and agility performance declined through the match simulation but surface type did not affect the decrease in performance. For example, the fatigue index of repeated sprints did not differ (P > 0.05) between the artificial, (6.9 ± 2.1%) and natural surface (7.4 ± 2.4%). The ability to turn after sprinting was affected by surface type but this difference was dependent on the type of turn. Although there were small differences in the ability to perform certain movements between artificial and natural surfaces, the results suggest that fatigue and physiological responses to football activity do not differ markedly between surface-type using the high-quality pitches of the present study.

  20. Surface chemistry of Ti6Al4V components fabricated using selective laser melting for biomedical applications.

    Science.gov (United States)

    Vaithilingam, Jayasheelan; Prina, Elisabetta; Goodridge, Ruth D; Hague, Richard J M; Edmondson, Steve; Rose, Felicity R A J; Christie, Steven D R

    2016-10-01

    Selective laser melting (SLM) has previously been shown to be a viable method for fabricating biomedical implants; however, the surface chemistry of SLM fabricated parts is poorly understood. In this study, X-ray photoelectron spectroscopy (XPS) was used to determine the surface chemistries of (a) SLM as-fabricated (SLM-AF) Ti6Al4V and (b) SLM fabricated and mechanically polished (SLM-MP) Ti6Al4V samples and compared with (c) traditionally manufactured (forged) and mechanically polished Ti6Al4V samples. The SLM-AF surface was observed to be porous with an average surface roughness (Ra) of 17.6±3.7μm. The surface chemistry of the SLM-AF was significantly different to the FGD-MP surface with respect to elemental distribution and their existence on the outermost surface. Sintered particles on the SLM-AF surface were observed to affect depth profiling of the sample due to a shadowing effect during argon ion sputtering. Surface heterogeneity was observed for all three surfaces; however, vanadium was witnessed only on the mechanically polished (SLM-MP and FGD-MP) surfaces. The direct and indirect 3T3 cell cytotoxicity studies revealed that the cells were viable on the SLM fabricated Ti6Al4V parts. The varied surface chemistry of the SLM-AF and SLM-MP did not influence the cell behaviour. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Comprehensive insights into the response of Alexandrium tamarense to algicidal component secreted by a marine bacterium

    Directory of Open Access Journals (Sweden)

    Xueqian eLei

    2015-01-01

    Full Text Available Harmful algal blooms occur throughout the world, threatening human health and destroying marine ecosystems. Alexandrium tamarense is a globally distributed and notoriously toxic dinoflagellate that is responsible for most paralytic shellfish poisoning incidents. The culture supernatant of the marine algicidal bacterium BS02 showed potent algicidal effects on A. tamarense ATGD98-006. In this study, we investigated the effects of this supernatant on A. tamarense at physiological and biochemical levels to elucidate the mechanism involved in the inhibition of algal growth by the supernatant of the strain BS02. Reactive oxygen species (ROS levels increased following exposure to the BS02 supernatant, indicating that the algal cells had suffered from oxidative damage. The levels of cellular pigments, including chlorophyll a and carotenoids, were significantly decreased, which indicated that the accumulation of ROS destroyed pigment synthesis. The decline of the maximum photochemical quantum yield (Fv/Fm and relative electron transport rate (rETR suggested that the photosynthesis systems of algal cells were attacked by the BS02 supernatant. To eliminate the ROS, the activities of antioxidant enzymes, including superoxide dismutase (SOD and catalase (CAT, increased significantly within a short period of time. Real-time PCR revealed changes in the transcript abundances of two target photosynthesis-related genes (psbA and psbD and two target respiration-related genes (cob and cox. The transcription of the respiration-related genes was significantly inhibited by the treatments, which indicated that the respiratory system was disturbed. Our results demonstrate that the BS02 supernatant can affect the photosynthesis process and might block the PS II electron transport chain, leading to the production of excessive ROS. The increased ROS can further destroy membrane integrity and pigments, ultimately inducing algal cell death.

  2. A role for immune responses against non-CS components in the cross-species protection induced by immunization with irradiated malaria sporozoites.

    Directory of Open Access Journals (Sweden)

    Marjorie Mauduit

    Full Text Available Immunization with irradiated Plasmodium sporozoites induces sterile immunity in rodents, monkeys and humans. The major surface component of the sporozoite the circumsporozoite protein (CS long considered as the antigen predominantly responsible for this immunity, thus remains the leading candidate antigen for vaccines targeting the parasite's pre-erythrocytic (PE stages. However, this role for CS was questioned when we recently showed that immunization with irradiated sporozoites (IrrSpz of a P. berghei line whose endogenous CS was replaced by that of P. falciparum still conferred sterile protection against challenge with wild type P. berghei sporozoites. In order to investigate the involvement of CS in the cross-species protection recently observed between the two rodent parasites P. berghei and P. yoelii, we adopted our gene replacement approach for the P. yoelii CS and exploited the ability to conduct reciprocal challenges. Overall, we found that immunization led to sterile immunity irrespective of the origin of the CS in the immunizing or challenge sporozoites. However, for some combinations, immune responses to CS contributed to the acquisition of protective immunity and were dependent on the immunizing IrrSpz dose. Nonetheless, when data from all the cross-species immunization/challenges were considered, the immune responses directed against non-CS parasite antigens shared by the two parasite species played a major role in the sterile protection induced by immunization with IrrSpz. This opens the perspective to develop a single vaccine formulation that could protect against multiple parasite species.

  3. Surface structures and dielectric response of ultrafine BaTiO3 particles

    International Nuclear Information System (INIS)

    Jiang, B.; Peng, J.L.; Bursill, L.A.

    1998-01-01

    Characteristic differences are observed for the dielectric response and microstructures of BaTiO 3 nanoscale fine powders prepared using sol gel (SG) and steric acid gel (SAG) methods. The former exhibit a critical size below which there is no paraelectric/ferroelectric phase transition whereas BaTiO 3 prepared via the SAG route remained cubic for all conditions. Atomic resolution images of both varieties showed a high density of interesting surface steps and facets. Computer simulated images of surface structure models showed that the outer (100) surface was typically a BaO layer and that at corners and ledges the steps are typically finished with Ba+2 ions; i.e. the surfaces and steps are Ba-rich. Otherwise the surfaces were typically clean and free of amorphous layers. The relationship between the observed surfaces structures and theoretical models for size effects on the dielectric properties is discussed. (authors)

  4. Antiplatelet and thermally responsive poly(N-isopropylacrylamide) surface with nanoscale topography.

    Science.gov (United States)

    Chen, Li; Liu, Mingjie; Bai, Hao; Chen, Peipei; Xia, Fan; Han, Dong; Jiang, Lei

    2009-08-05

    Nanoscale topography was constructed on a thermally responsive poly(N-isopropylacrylamide) (PNIPAAm) surface by grafting the polymer from silicon nanowire arrays via surface-initiated atom transfer radical polymerization. The as-prepared surface showed largely reduced platelet adhesion in vitro both below and above the lower critical solution temperature (LCST) of PNIPAAm ( approximately 32 degrees C), while a smooth PNIPAAm surface exhibited antiadhesion to platelets only below the LCST. Contact angle and adhesive force measurements on oil droplets (1,2-dichloroethane) in water demonstrated that the nanoscale topography kept a relatively high ratio of water content on the as-prepared surface and played a key role in largely reducing the adhesion of platelets; however, this effect did not exist on the smooth PNIPAAm surface. The results can be used to extend the applications of PNIPAAm in the fields of biomaterials and biomedicine under human physiological temperature and provide a new strategy for fabricating other blood-compatible materials.

  5. Reliability-based design optimization via high order response surface method

    International Nuclear Information System (INIS)

    Li, Hong Shuang

    2013-01-01

    To reduce the computational effort of reliability-based design optimization (RBDO), the response surface method (RSM) has been widely used to evaluate reliability constraints. We propose an efficient methodology for solving RBDO problems based on an improved high order response surface method (HORSM) that takes advantage of an efficient sampling method, Hermite polynomials and uncertainty contribution concept to construct a high order response surface function with cross terms for reliability analysis. The sampling method generates supporting points from Gauss-Hermite quadrature points, which can be used to approximate response surface function without cross terms, to identify the highest order of each random variable and to determine the significant variables connected with point estimate method. The cross terms between two significant random variables are added to the response surface function to improve the approximation accuracy. Integrating the nested strategy, the improved HORSM is explored in solving RBDO problems. Additionally, a sampling based reliability sensitivity analysis method is employed to reduce the computational effort further when design variables are distributional parameters of input random variables. The proposed methodology is applied on two test problems to validate its accuracy and efficiency. The proposed methodology is more efficient than first order reliability method based RBDO and Monte Carlo simulation based RBDO, and enables the use of RBDO as a practical design tool.

  6. Histological response of human pulps capped with calcium hydroxide and a self-etch adhesive containing an antibacterial component.

    Science.gov (United States)

    Parthasarathy, Ambalavanan; Kamat, Sharad B; Kamat, Mamta; Kidiyoor, Krishnamurthy Haridas

    2016-01-01

    To compare human pulp tissue response following direct pulp capping with calcium hydroxide and a self-etch adhesive containing antibacterial component. Sixty-six erupted sound premolars scheduled to be extracted for orthodontic reasons were selected from 17 human subjects. Pulp exposures were made. Direct pulp capping was then performed using calcium hydroxide and a self-etch adhesive containing antibacterial component in its primer. The teeth were then restored with composite resin. Two teeth were maintained intact as a control group. After 7 and 30 days, teeth were extracted and processed for light microscopic examination using a histological scoring system. The teeth were divided into four groups (N = 16) according to the pulp capping materials used and their days of extraction. The results were then statistically analyzed by Mann-Whitney U-test. After the 7-day observation period, the inflammatory reaction to the self-etch adhesive containing antibacterial component group was significantly less severe than that in the calcium hydroxide group (P self-etch adhesive group were significantly less common than those in the calcium hydroxide group (P < 0.05).

  7. Proceedings of 1999 U.S./Japan Workshop (99FT-05) On High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    Energy Technology Data Exchange (ETDEWEB)

    NYGREN,RICHARD E.; STAVROS,DIANA T.

    2000-06-01

    The 1999 US-Japan Workshop on High Heat Flux Components and Plasma Surface Interactions in Next Step Fusion Devices was held at the St. Francis Hotel in Santa Fe, New Mexico, on November 1-4, 1999. There were 42 presentations as well as discussion on technical issues and planning for future collaborations. The participants included 22 researchers from Japan and the United States as well as seven researchers from Europe and Russia. There have been important changes in the programs in both the US and Japan in the areas of plasma surface interactions and plasma facing components. The US has moved away from a strong focus on the ITER Project and has introduced new programs on use of liquid surfaces for plasma facing components, and operation of NSTX has begun. In Japan, the Large Helical Device began operation. This is the first large world-class confinement device operating in a magnetic configuration different than a tokamak. In selecting the presentations for this workshop, the organizers sought a balance between research in laboratory facilities or confinement devices related to plasma surface interactions and experimental research in the development of plasma facing components. In discussions about the workshop itself, the participants affirmed their preference for a setting where ''work-in-progress'' could be informally presented and discussed.

  8. Radiation reflection from star surface reveals the mystery of interpulse shift and appearance of high frequency components in the Crab pulsar

    Science.gov (United States)

    Kontorovich, V. M.; Trofymenko, S. V.

    2017-12-01

    A new mechanism of radiation emission in the polar gap of a pulsar is discussed. It is based on the curvature radiation which is emitted by positrons moving towards the surface of neutron star along field lines of the inclined magnetic field and reflects from the surface. This mechanism explains the mystery of the interpulse shift and appearance of additional components in the emission of Crab pulsar at high frequencies discovered by Moffett and Hankins twenty years ago. We discuss coherence, energy flux and spectrum of the reflected radiation, appearance and disappearance of the interpulse position shift with the frequency increase. It is also possible that a nonlinear reflection (stimulated scattering) from the star surface is observed in the form of HF components. The frequency drift of these components, discovered by Hankins, Jones and Eilek, is discussed. The nonlinear reflection is associated with “Wood’s anomaly” at the diffracted waves grazing along the star surface. Two components can arise due to slow and fast waves which are present in the magnetospheric plasma. The possible scheme of their appearance due to birefringence at the reflection is also proposed.

  9. Behavioral responses to mammalian blood odor and a blood odor component in four species of large carnivores.

    Directory of Open Access Journals (Sweden)

    Sara Nilsson

    Full Text Available Only little is known about whether single volatile compounds are as efficient in eliciting behavioral responses in animals as the whole complex mixture of a behaviorally relevant odor. Recent studies analysing the composition of volatiles in mammalian blood, an important prey-associated odor stimulus for predators, found the odorant trans-4,5-epoxy-(E-2-decenal to evoke a typical "metallic, blood-like" odor quality in humans. We therefore assessed the behavior of captive Asian wild dogs (Cuon alpinus, African wild dogs (Lycaon pictus, South American bush dogs (Speothos venaticus, and Siberian tigers (Panthera tigris altaica when presented with wooden logs that were impregnated either with mammalian blood or with the blood odor component trans-4,5-epoxy-(E-2-decenal, and compared it to their behavior towards a fruity odor (iso-pentyl acetate and a near-odorless solvent (diethyl phthalate as control. We found that all four species displayed significantly more interactions with the odorized wooden logs such as sniffing, licking, biting, pawing, and toying, when they were impregnated with the two prey-associated odors compared to the two non-prey-associated odors. Most importantly, no significant differences were found in the number of interactions with the wooden logs impregnated with mammalian blood and the blood odor component in any of the four species. Only one of the four species, the South American bush dogs, displayed a significant decrease in the number of interactions with the odorized logs across the five sessions performed per odor stimulus. Taken together, the results demonstrate that a single blood odor component can be as efficient in eliciting behavioral responses in large carnivores as the odor of real blood, suggesting that trans-4,5-epoxy-(E-2-decenal may be perceived by predators as a "character impact compound" of mammalian blood odor. Further, the results suggest that odorized wooden logs are a suitable manner of environmental

  10. Behavioral responses to mammalian blood odor and a blood odor component in four species of large carnivores.

    Science.gov (United States)

    Nilsson, Sara; Sjöberg, Johanna; Amundin, Mats; Hartmann, Constanze; Buettner, Andrea; Laska, Matthias

    2014-01-01

    Only little is known about whether single volatile compounds are as efficient in eliciting behavioral responses in animals as the whole complex mixture of a behaviorally relevant odor. Recent studies analysing the composition of volatiles in mammalian blood, an important prey-associated odor stimulus for predators, found the odorant trans-4,5-epoxy-(E)-2-decenal to evoke a typical "metallic, blood-like" odor quality in humans. We therefore assessed the behavior of captive Asian wild dogs (Cuon alpinus), African wild dogs (Lycaon pictus), South American bush dogs (Speothos venaticus), and Siberian tigers (Panthera tigris altaica) when presented with wooden logs that were impregnated either with mammalian blood or with the blood odor component trans-4,5-epoxy-(E)-2-decenal, and compared it to their behavior towards a fruity odor (iso-pentyl acetate) and a near-odorless solvent (diethyl phthalate) as control. We found that all four species displayed significantly more interactions with the odorized wooden logs such as sniffing, licking, biting, pawing, and toying, when they were impregnated with the two prey-associated odors compared to the two non-prey-associated odors. Most importantly, no significant differences were found in the number of interactions with the wooden logs impregnated with mammalian blood and the blood odor component in any of the four species. Only one of the four species, the South American bush dogs, displayed a significant decrease in the number of interactions with the odorized logs across the five sessions performed per odor stimulus. Taken together, the results demonstrate that a single blood odor component can be as efficient in eliciting behavioral responses in large carnivores as the odor of real blood, suggesting that trans-4,5-epoxy-(E)-2-decenal may be perceived by predators as a "character impact compound" of mammalian blood odor. Further, the results suggest that odorized wooden logs are a suitable manner of environmental enrichment

  11. Human alveolar macrophage responses to air pollution particulates are associated with insoluble components of coarse material, including particulate endotoxin.

    Science.gov (United States)

    Soukup, J M; Becker, S

    2001-02-15

    Inhalation of particulate matter in the ambient air has been shown to cause pulmonary morbidity and exacerbate asthma. Alveolar macrophage (AM) are essential for effective removal of inhaled particles and microbes in the lower airways. While some particles minimally effect AM function others inhibit antimicrobial activity or cause cytokine and growth factor production leading to inflammation and tissue remodeling. This study has investigated the effects of water soluble (s) and insoluble (is) components of Chapel Hill, North Carolina ambient particulate matter in the size ranges 0.1-2.5 microm (PM2.5) and 2.5-10 microm (PM10) diameter, on human AM IL-6, TNFalpha, and MCP-1 cytokine production and host defense mechanisms including phagocytosis and oxidant production. Cytokines were found to be induced by isPM10 to a much higher extent (>50-fold) than sPM10, which in turn stimulated production better than isPM2.5, while sPM2.5 was inactive. Previous studies have indicated that endotoxin (ETOX) is a component of sPM10 responsible for cytokine production. Here, it is shown that inhibition of isPM10-induced cytokine production was partially achieved with polymyxin B and LPS-binding protein (LBP), but not with a metal chelator, implicating ETOX as a cytokine-inducing moiety also in isPM10. In addition to inducing cytokines, exposure to isPM10, but not the other PM fractions, also inhibited phagocytosis and oxidant generation in response to yeast. This inhibition was ETOX independent. The decrease in host defenses may be the result of apoptosis in the AM population, which was also found to be specifically caused by isPM10. These results show that the functional capacity of AM is selectively modulated by insoluble components of coarse PM, including the biocontaminant ETOX.

  12. Response Surfaces for Fresh and Hardened Properties of Concrete with E-Waste (HIPS

    Directory of Open Access Journals (Sweden)

    K. Senthil Kumar

    2014-01-01

    Full Text Available The fresh and hardened properties of concrete with E-waste plastic, that is, high impact polystyrene (HIPS, as a partial replacement for coarse aggregate were analyzed using response surface methodology (RSM. Face-centred central composite response surface design was used in this study. The statistical models were developed between the factors (HIPS and water cement ratio and their response variables (slump, fresh density, dry density, compressive strength, spilt tensile strength, and flexural strength. The Design-Expert 9.0.3 software package was used to analyze the experimental values. The relationships were established and final mathematical models in terms of coded factors from predicted responses were developed. The effects of factors on properties for all variables were seen visually from the response surface and contour plot. Validation of experiments has shown that the experimental value closely agreed with the predicted value, which validates the calculated response surface models with desirability = 1. The HIPS replacement influenced all the properties of concrete than water cement ratio. Even though all properties show the decline trend, the experimented values and predicted values give a hope that the E-waste plastic (HIPS can be used as coarse aggregate up to certain percentage of replacement in concrete which successively reduces the hazardous solid waste problem and conserves the natural resources from exhaustion.

  13. Effect of surface cleaning on spectral response for InGaAs photocathodes.

    Science.gov (United States)

    Jin, Muchun; Zhang, Yijun; Chen, Xinlong; Hao, Guanghui; Chang, Benkang; Shi, Feng

    2015-12-20

    Photocathode surface treatment aims to obtain high sensitivity, where the key point is to acquire an atomically clean surface. Various surface cleaning methods for removing contamination from InGaAs photocathode surfaces were investigated. The atomic compositions of InGaAs photocathode structures and surfaces were measured by x-ray photoelectron spectroscopy and Ar ion sputtering. After surface cleaning, the InGaAs surface is arsenoxide-free, however, a small amount of Ga2O3 and In2O3 still can be found. The 1:1 mixed solution of hydrochloric acid to deionized water followed by thermal annealing at 525°C has been demonstrated to be the best choice in dealing with the surface oxides. After the Cs/O activation, a surface model was proposed where the oxides on the surface will lead to a positive electron affinity, adversely affecting low-energy electrons escaping to the vacuum, which is reflected by the photocurrent curves and the spectral response curves.

  14. Statistical analysis of surface roughness in turning based on cutting parameters and tool vibrations with response surface methodology (RSM)

    Science.gov (United States)

    Touati, Soufiane; Mekhilef, Slimane

    2018-03-01

    In this paper, we present an experimental study to determine the effect of the cutting conditions and tool vibration on the surface roughness in finish turning of 32CrMoV12-28 steel, using carbide cutting tool YT15. For these purposes, a linear quadratic model in interaction of connecting surface roughness (Ra, Rz) with different combinations of cutting parameters such as cutting speed, feed rate, depth of cut and tool vibration, in radial and in tangential cutting force directions (Vy) and (Vz) is elaborated. In order to express the degree of interaction of cutting parameters and tool vibration, a multiple linear regression and response surface methodology are adopted. The application of this statistical technique for predicting the surface roughness shows that the feed rate is the most dominant factor followed by the cutting speed. However, the depth of the cut and tool vibrations have secondary effect. The presented models have some interest since they are used in the cutting process optimization.

  15. Method for Constructing Composite Response Surfaces by Combining Neural Networks with other Interpolation or Estimation Techniques

    Science.gov (United States)

    Rai, Man Mohan (Inventor); Madavan, Nateri K. (Inventor)

    2003-01-01

    A method and system for design optimization that incorporates the advantages of both traditional response surface methodology (RSM) and neural networks is disclosed. The present invention employs a unique strategy called parameter-based partitioning of the given design space. In the design procedure, a sequence of composite response surfaces based on both neural networks and polynomial fits is used to traverse the design space to identify an optimal solution. The composite response surface has both the power of neural networks and the economy of low-order polynomials (in terms of the number of simulations needed and the network training requirements). The present invention handles design problems with many more parameters than would be possible using neural networks alone and permits a designer to rapidly perform a variety of trade-off studies before arriving at the final design.

  16. Continuous vs. pulsating flow boiling. Part 2: Statistical comparison using response surface methodology

    DEFF Research Database (Denmark)

    Kærn, Martin Ryhl; Elmegaard, Brian; Meyer, Knud Erik

    2016-01-01

    Response surface methodology is used to investigate an active method for flow boiling heat transfer enhancement by means of fluid flow pulsation. The flow pulsations are introduced by a flow modulating expansion device and compared with the baseline continuous flow provided by a stepper......-motor expansion valve. Two experimental designs (data point sets) are generated using a modified Central Composite Design for each valve and their response surfaces are compared using the quadratic model. Statistical information on the significant model terms are used to clarify whether the effect of fluid flow....... The response surface comparison reveals that the flow pulsations improves the time-averaged heat transfer coefficient by as much as 10 % at the smallest cycle time compared with continuous flow. On the other hand, at highest cycle time and heat flux, the reduction may be as much as 20 % due to significant dry...

  17. Components of near-surface energy balance derived from satellite soundings – Part 1: Net available energy

    OpenAIRE

    K. Mallick; A. Jarvis; G. Wohlfahrt; G. Kiely; T. Hirano; A. Miyata; S. Yamamoto; L. Hoffmann

    2014-01-01

    This paper introduces a relatively simple method for recovering global fields of near-surface net available energy (the sum of the sensible and latent heat flux or the difference between the net radiation and surface heat accumulation) using satellite visible and infra-red products derived from the AIRS (Atmospheric Infrared Sounder) and MODIS (MOderate Resolution Imaging Spectroradiometer) platforms. The method focuses on first specifying net surface radiation by con...

  18. Simulated studies of wear and friction in total hip prosthesis components with various ball sizes and surface finishes

    Science.gov (United States)

    Swikert, M. A.; Johnson, R. L.

    1976-01-01

    Experiments were conducted on a newly designed total hip joint simulator. The apparatus closely simulates the complex motions and loads of the human hip in normal walking. The wear and friction of presently used appliance configurations and materials were determined. A surface treatment of the metal femoral ball specimens was applied to influence wear. The results of the investigation indicate that wear can be reduced by mechanical treatment of metal femoral ball surfaces. A metallographic examination and surface roughness measurements were made.

  19. Independent component analysis for cochlear implant artifacts attenuation from electrically evoked auditory steady-state response measurements

    Science.gov (United States)

    Deprez, Hanne; Gransier, Robin; Hofmann, Michael; van Wieringen, Astrid; Wouters, Jan; Moonen, Marc

    2018-02-01

    Objective. Electrically evoked auditory steady-state responses (EASSRs) are potentially useful for objective cochlear implant (CI) fitting and follow-up of the auditory maturation in infants and children with a CI. EASSRs are recorded in the electro-encephalogram (EEG) in response to electrical stimulation with continuous pulse trains, and are distorted by significant CI artifacts related to this electrical stimulation. The aim of this study is to evaluate a CI artifacts attenuation method based on independent component analysis (ICA) for three EASSR datasets. Approach. ICA has often been used to remove CI artifacts from the EEG to record transient auditory responses, such as cortical evoked auditory potentials. Independent components (ICs) corresponding to CI artifacts are then often manually identified. In this study, an ICA based CI artifacts attenuation method was developed and evaluated for EASSR measurements with varying CI artifacts and EASSR characteristics. Artifactual ICs were automatically identified based on their spectrum. Main results. For 40 Hz amplitude modulation (AM) stimulation at comfort level, in high SNR recordings, ICA succeeded in removing CI artifacts from all recording channels, without distorting the EASSR. For lower SNR recordings, with 40 Hz AM stimulation at lower levels, or 90 Hz AM stimulation, ICA either distorted the EASSR or could not remove all CI artifacts in most subjects, except for two of the seven subjects tested with low level 40 Hz AM stimulation. Noise levels were reduced after ICA was applied, and up to 29 ICs were rejected, suggesting poor ICA separation quality. Significance. We hypothesize that ICA is capable of separating CI artifacts and EASSR in case the contralateral hemisphere is EASSR dominated. For small EASSRs or large CI artifact amplitudes, ICA separation quality is insufficient to ensure complete CI artifacts attenuation without EASSR distortion.

  20. Optimization of Solid-Liquid Extraction of Antioxidants from Black Mulberry Leaves by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Zoran Zeković

    2012-01-01

    Full Text Available The extraction of active components from natural sources depends on different factors. The knowledge of the effects of different extraction parameters is useful for the optimization of the process, as well for the ability to predict the extraction yield. The aim of this study is to examine the influence of solvent concentration (ethanol/water 40–80 %, by volume, temperature (40–80 °C and solvent/raw material ratio (10–30 mL/g on the extraction yield of phenolic compounds, flavonoids and antioxidant activity from black mulberry (Morus nigra L. leaves. Experimental values of total phenolic content were in the range from 18.6 to 48.7 mg of chlorogenic acid equivalents per g of dried leaves and total flavonoids in the range from 6.0 to 21.4 mg of rutin eqivalents per g of dried leaves. Antioxidant activity expressed as the inhibition concentration at 50 % (IC50 value was in the range from 0.019 to 0.078 mg of mulberry extract per mL. Response surface methodology (RSM was used to determine the optimum extraction conditions and to investigate the effect of different variables on the observed properties of mulberry leaf extracts. The results show a good fit to the proposed model (R˄2>0.90. The optimal conditions for obtaining the highest extraction yield of phenolics and flavonoids were within the experimental range. The experimental values agreed with those predicted, thus indicating suitability of the used model and the success of RSM in optimizing the investigated extraction conditions.